How Far Is The Moon From Earth?
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- 1 How many kilometers is the Moon from Earth?
- 2 How far is space from Earth?
- 3 How long is 40 light years in human years?
- 4 How is space cold?
- 5 What is moon made of?
- 6 Which country is the closest to the Moon?
- 7 Is there a photo on the Moon?
- 8 Does water freeze in space?
- 9 Can it be hot in space?
- 10 How long is trip to Mars?
How long does it take to get to Moon from Earth?
It takes about 3 days for a spacecraft to reach the Moon. During that time a spacecraft travels at least 240,000 miles (386,400 kilometers) which is the distance between Earth and the Moon. The specific distance depends on the specific path chosen.
How many kilometers is the Moon from Earth?
The average distance to the moon is 382,500 kilometers. The distance varies because the moon travels around Earth in an elliptical orbit. At perigee, the point at which the moon is closest to Earth, the distance is approximately 360,000 kilometers.
How far is space from Earth?
Background – We often think of space as being very far away. Planets are many millions or even billions of miles away, and stars are so far away that their distances are measured in light years. (A light year is the distance light travels in a year and is equal to six trillion miles.) Yet the edge of space – or the point where we consider spacecraft and astronauts to have entered space, known as the Von Karman Line – is only 62 miles (100 kilometers) above sea level. An image taken in October 2018 shows the International Space Station flying above Earth. Credit: NASA | › Full image and caption
How long is 40 light years in human years?
Whence the travel time for 40 light years will be 40×30000016.8≈ 700000years.
How is space cold?
Far outside our solar system and out past the distant reaches of our galaxy —in the vast nothingness of space—the distance between gas and dust particles grows, limiting their ability to transfer heat. Temperatures in these vacuous regions can plummet to about -455 degrees Fahrenheit (2.7 kelvin).
- Are you shivering yet? But understanding how cold is space, and why the vacuum of space is this cold, is complicated.
- For physicists, knowing what the temperature in space is is all about velocity and motion.
- When we talk about the temperature in a room, that’s not the way a scientist would talk about it,” Jim Sowell, an astronomer at the Georgia Institute of Technology, tells Popular Mechanics,
“We would use the expression ‘heat’ to define the speeds of all the particles in a given volume.” ⚠️ Most scientists use the kelvin instead of Fahrenheit to describe extremely cold temperatures, so we’ll be doing that here, too. Most, if not all of the heat in the universe comes from stars like our sun,
- Inside the sun, where nuclear fusion occurs, temperatures can swell to 15 million kelvin.
- On the surface, they only reach up to about 5,800 kelvin.) The heat that leaves the sun and other stars travels across space as infrared waves of energy called solar radiation.
- These solar rays only heat the particles in their path, so anything not directly in view of the sun stays cool.
Like, really cool. At night, the surface of even the closest planet to the sun, Mercury, drops to about 95 kelvin. Pluto’s surface temperature reaches about 40 kelvin. Coincidentally, the lowest temperature ever recorded in our solar system was clocked much closer to home.
What is moon made of?
What is the moon made of? – The moon very likely has a very small core, just 1% to 2% of the moon’s mass and roughly 420 miles (680 km) wide. It likely consists mostly of iron, but may also contain large amounts of sulfur and other elements. The moon likely has a very small solid iron core. (Image credit: Karl Tate, SPACE.com) The moon’s rocky mantle is about 825 miles (1,330 km) thick and made up of dense rocks rich in iron and magnesium. Magma in the mantle made its way to the surface in the past and erupted volcanically for more than a billion years — from at least four billion years ago to fewer than three billion years ago. The moon’s north pole as seen by NASA’s Galileo spacecraft in 1998. This image is a mosaic of multiple images taken by Galileo. (Image credit: NASA/JPL/USGS) Like our solar system’s four innermost planets, the moon is rocky. It’s pockmarked with craters created by asteroid impacts millions of years ago and, because there is no weather, the craters have not eroded.
Photos : Our changing moon The average composition of the lunar surface by weight is roughly 43% oxygen, 20% silicon, 19% magnesium, 10% iron, 3% calcium, 3% aluminum, 0.42% chromium, 0.18% titanium and 0.12% manganese. Orbiting spacecraft have found traces of water on the lunar surface that may have originated from deep underground.
They have also located hundreds of pits that could one-day house explorers living on the moon long-term. Ongoing observations from the Lunar Reconnaissance Orbiter (LRO) have shown that water is more abundant on slopes facing the lunar south pole, although scientists do caution that the water quantity is comparable to an extremely dry desert.
How many countries have landed on the moon?
How Many Countries Have Successfully Explored the Lunar Surface? how many countries have landed on the moon The answer to “how many countries have landed on the moon?” as of August 2023 is three: the United States, Russia, India and China. However, with India’s recent achievements in lunar exploration, India joined this exclusive club.
- The first manned moon landing took place on July 20, 1969, marking a significant milestone in the history of space exploration.
- Since that historic moment, a few other countries have embarked on their own lunar missions, hoping to uncover the mysteries of the moon and solidify their place in space exploration history.
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How far is our universe?
How Far Away is the Edge of the Universe? | Museum of Science, Boston We ask Museum educator Janine all your questions about how far away things are, from the Moon to the end of the universe, during this Pulsar podcast brought to you by #MOSatHome. We ask questions submitted by listeners, so if you have a question you’d like us to ask an expert, send it to us at [email protected].
ERIC: At the Museum of Science, we’re often asked how far away things are in space. The simple answer is, really, really far away. Today on Pulsar, we’ll get some more exact answers, starting with the closest things to our home planet and making our way out to the edge of the universe. And along the way, we’ll find out: how do we know how far away these things are? Thanks to Facebook Boston for supporting this episode of Pulsar.
I’m your host, Eric, And my guest today is Janine from our forums department. Janine, thanks so much for going on this journey through the universe with me. JANINE: Yeah, absolutely, happy to be here. ERIC: So let’s start with the closest natural object to us here on the Earth.
How far away is the moon? JANINE: OK, so I’ll use a unit of measurement that you’re probably pretty familiar with. It’s about 238,855 miles on average, and I say on average, because the distance does change. The moon does not orbit the Earth in a perfect circle, but that’s kind of an abstract thing, and it doesn’t really mean anything to you, right? So if the Earth was the size of a basketball, the moon would be about the size of a tennis ball.
They would be about 23 feet, 9 inches apart, which is about 30 earths, which is crazy to me. ERIC: It’s further away than you would think. JANINE: It really is. I always think everything in space has more space than we expect it to, so even our closest neighbor is 30 times away the size we are.
- Everything that you put on a mission to go into space costs fuel, so the more fuel you have, so to go faster, would actually make you weigh more, so there’s this balance of power and efficiency, and you’re always trying to make it as light as possible.
- It was kind of more of a circle around the Earth and then a couple of circles around the moon and then a landing rather than a straight shot.
- ERIC: So we could have got there a little bit quicker than four days, but not too much quicker.
- JANINE: Yeah, I think they say, on average, over the course of all of the missions is about three days to get from Earth to the moon.
ERIC: So we haven’t sent any astronauts to the moon in nearly 50 years. Lately, they spend their time on the International Space Station. How far away from Earth’s surface is that? JANINE: So that’s actually a lot closer. It’s only about 254 miles away, and I was trying to figure out what cities on the Earth are at least in the US are close to that distance, and I figured out it’s about the distance if you were to fly from LA to Las Vegas.
ERIC: And the next object on our list at the center of the solar system, the sun. How far away is that? JANINE: So sun is our closest star, and it’s 92 million miles away, which is crazy, and now we’re starting to get to these distances in space where talking about them in miles really doesn’t mean anything.
So actually, the average distance from the Earth to the sun is a unit that astronomers used called an astronomical unit, so we’ve just decided that, for math, it’s a lot easier to figure out, we’ll just say that the distance from the Earth to the sun is 1, and then all of our math can be easier.
If you could travel at the speed of light, which you can’t because you’re made of mass, but if you could, it would take 8.3 minutes. The thing that blows my mind away about this is, since it takes eight minutes for light to travel, the sun could go out suddenly, and we wouldn’t know about it for eight minutes.
What Happens if the Moon Crashes into Earth?
ERIC: Because it would take eight minutes for light to stop showing up on Earth. JANINE: Yeah, it’s crazy. ERIC: So jumping right out to the edge of our neighborhood, we often get asked how big the solar system is. So how far away is the edge of the solar system? Does it even have an edge? JANINE: OK, so it’s hard to talk about the solar system and what does it mean to be part of the solar system.
- We’re considering the things in the solar system to be the things that are most pulled on by the sun, and so that’s at the edge of the Oort cloud, and to go back to that unit of the astronomical unit, that’s about 100,000 astronomical units away.
- ERIC: So start on Earth, head past the sun, then go 100,000 times further than that before you leave the solar system.
- JANINE: Yeah, isn’t that nuts?
ERIC: It is. That’s already so far, and speaking of that, when we mentioned the outer part of the solar system, we get asked about the robots that we’ve sent deep into space. So how far away is the furthest spacecraft that we’ve launched from the earth? JANINE: OK, so I looked this up yesterday.
So it’s a little bit further out now, but since we’re talking about astronomy, everything in astronomy has a big error range anyway, so that’s fine. Voyager 1, which was launched in 1977 is about 150 astronomical units away from the Earth. ERIC: So that’s wicked far, but it’s not anywhere close to leaving behind the effect of the sun’s gravity.
OK, so leaving the solar system behind, what’s the next closest star to us and how far away is it? And since this question comes up a lot how long would it take a rocket to get there? JANINE: So the closest star to us is actually part of a three star system.
The closest one of those three stars is Proxima Centauri, which is 4.22 light years away, and so if you could travel at the speed of light, it would take you 4.22 years to get there, but we can’t travel at the speed of light, so how long would it take Voyager 1 to get there? It would take over 73,000 years.
ERIC: So using current rocket technology, we’re just not going to get there any time soon. JANINE: No. No, space, as I think we’re going to establish in this podcast, is very big. ERIC: Now, before we continue our journey, this would be a good place to bring up a question we got from Sophie.
- The planets are pretty easy to measure, we’ve been to them all, we can see them moving, how can we measure the distance to stars and galaxies?
- JANINE: Yeah, so astronomers actually use a bunch of different tools, and we call it the distance ladder, although I like to think about it as if you had a bunch of yardsticks and you tried to tape them together and that first yardstick is really strong and by the end it’s bending over and not super great, because our error of knowing what is correct and how accurate something is increases as we use different steps on this ladder.
- But the first step that you can use is called parallax, and you can actually do an experiment with this right now if you want to.
You can hold a finger in front of your face and close your left eye and then close your right eye and look at what happens behind it. And you’ll notice that, with respect to the things behind it, it moves in front, just because there’s a little bit of distance between each eye.
- And so we can do that with stars, but not with our eyes, because that’s too small of a distance with respect to how far away stars are.
- ERIC: Yeah, stars don’t seem to move too much if you just go outside and wink at them back and forth a bunch of times.
- JANINE: Yeah, so what we can actually do is use the Earth in its orbit as that kind of blinking, and so if we go out and measure in June and then we go out and measure in December, now we’ve got six months apart so we’re halfway around the sun.
So we’ve got that entire distance, which is 2 AU, going back to that astronomical unit is the longest baseline we can get while we’re on Earth. And we can look at stars and see how they change with respect to the things behind them, and that’s how we can get a direct distance.
ERIC: So parallax seems pretty good for stars that are fairly close, but you mentioned other methods too. So what’s next? JANINE: Yeah, so the next step is something called a standard candle, and actually the first standard candle was discovered not too far from the Museum of Science by Henrietta Swann Levitt at the Harvard College Observatory back in the early 1900s.
She was a computer there. If you’re interested in this at all, there’s a really good book called The Glass Universe that talks about all of these computers who worked at the Harvard College Observatory, including Annie Jump Cannon, who’s very famous for figuring out the brightness of stars, a relationship about that.
Henrietta Swan Levitt determined this first standard candle. So she was working at the Harvard College Observatory, examining photographic plates from telescopes. So these telescopes were taking all these images and they needed people to reduce the data, which is something that a lot of physical computers do now, but people did back then.
And she was looking at a particular type of star called a Cepheid variable, and she realized that there was some sort of a relationship between how fast they dimmed and brightened and what their brightness was. These Cepheid variables are very consistent, so she had this idea that, because luminosity and period are the same, maybe they could be used to figure out how far away something is.
- So the standard candle idea is that a candle has an intrinsic brightness that we know.
- We can determine it because of some sort of physical relationship or just studying physics in general.
- This star, if we know this other thing about it, we know how bright it is if you were standing at a certain distance from it.
OK, so if we know how bright it should be and we know how bright we’re observing it, we can actually figure out the distance based on that, right? If you know how bright your flashlight is and you know how bright you’re seeing it, you can figure out how far away it is.
- ERIC: So the further away something is, the dimmer it appears to us, and if we know its true brightness, it’s pretty easy math to calculate how far away it must be to appear how we see it.
- JANINE: Yeah, exactly.
- So they figured out that these Cepheid variables could be used in this way as a standard candle.
Although, my personal favorite standard candle is a type 1A supernova.
- And that’s entirely because, when I was in college, I worked on a project on SS Cygni, which is a very well known cataclysmic variable.
- And what a cataclysmic variable is is it’s a red giant star, and it has a partner a star, a binary star companion, called a white dwarf, and actually, most stars in the galaxy are in multiple star systems, so it’s pretty normal to find a binary star system.
- So in a cataclysmic variable, you have this red giant and you had this white dwarf, and the white dwarf is close enough to the red giant that it steals mass from the red giant.
- It doesn’t know what that mass belongs to and it takes it on and it turns into this disk that goes around the white dwarf and there is a point at which there’s too much mass in the disk, it becomes unstable, it all falls on to the white dwarf and the white dwarf brightness suddenly.
- And because we know what that mass is, there’s a mathematical physical relationship between how much mass is in that disk.
You then know how bright it is. You’ve got your E equals mc squared, so you know how much mass is going to turn into an energy, and then you can figure out how far away is. ERIC: And this takes us even further out on the distance ladder, because these things are so bright, we can see them from really far away and we can measure larger distances.
JANINE: Yeah. Yeah, and actually, that’s how we got our first distance to the Andromeda galaxy was Edwin Hubble, who you may have heard of because of a certain telescope. There was a person that that’s named after. So Edwin Hubble in 1924 used Cepheid variables that, as Henrietta Swan Levitt had posited you could, to figure out how far away the Andromeda nebula was, because at that point they didn’t know that galaxies were galaxies.
But he used it to prove that it wasn’t inside of the Milky Way, and his number was about 900,000 light years. He used 12 Cepheids to figure that out. We now think it’s about 2.537 million light years, but. ERIC: So in the ballpark, not too bad for telescopes from 100 years ago.
- JANINE: It’s astronomy, right? So it’s pretty close.
- ERIC: All right, we can use these methods to estimate distances to other galaxies that make up the universe, and now, we’re at the end of our journey.
- How far away is the edge of the universe? JANINE: This one’s harder.
- There isn’t an edge to the universe, at least not one that we know of, and people who are trying to figure out this are actually called cosmologists.
So there are people who study what the shape of the universe is, how big it is, how it formed, all of these kinds of things. But we can talk about the edge of the visible universe or actually how far back in time, we can see. We talked about that time limit and how long it would take light from the sun to get to the earth and how we wouldn’t know for eight minutes.
- Well, that applies to everything that we see in space, which means looking out into space is basically a time machine, right? We’re looking back in time the further out we go because it takes time for light to travel to us.
- So the furthest out we can see is about 46.5 billion light years away, which is crazy, but it also means you can look back into the past and try to figure out how the universe formed, which again, is what cosmologists do.
ERIC: Well, Janine, thanks so much for telling us how far away everything in the universe is. JANINE: You are so, so welcome. ERIC: You can find out more about the structure of the universe by tuning in to one of our virtual planetarium shows from the comfort of your own home.
How cold is outer space?
And how does the coldest place on Earth compare? Space is very, very cold. The baseline temperature of outer space is 2.7 kelvins — minus 454.81 degrees Fahrenheit, or minus 270.45 degrees Celsius — meaning it is barely above absolute zero, the point at which molecular motion stops.
Why is space dark?
The dark night sky, as seen from Arches National Park in Utah (Image credit: Pascal Fraboul / EyeEm via Getty Images) Look up at the night sky with your own eyes, or marvel at images of the universe online, and you’ll see the same thing: the inky, abysmal blackness of space, punctuated by bright stars, planets or spacecraft.
- But why is it black? Why isn’t space colorful, like the blue daytime sky on Earth ? Surprisingly, the answer has little to do with a lack of light.
- You would think that since there are billions of stars in our galaxy, billions of galaxies in the universe and other objects, such as planets, that reflect light, that when we look up at the sky at night, it would be extremely bright,” Tenley Hutchinson-Smith, a graduate student of astronomy and astrophysics at the University of California, Santa Cruz (UCSC), told Live Science in an email.
“But instead, it’s actually really dark.” Related: How long is a galactic year? Hutchinson-Smith said this contradiction, known in physics and astronomy circles as Olbers’ paradox, can be explained by the theory of space-time expansion — the idea that “because our universe is expanding faster than the speed of light the light from distant galaxies might be stretching and turning into infrared waves, microwaves and radio waves, which are not detectable by our human eyes,” And because they are undetectable, they appear dark (black) to the naked eye.
Miranda Apfel, who is also a graduate student of astronomy and astrophysics at UCSC, agreed with Hutchinson-Smith. “Stars give off light in all colors, even colors not visible to the human eye, like ultraviolet or infrared,” she told Live Science. “If we could see microwaves, all of space would glow.” Apfel said this is because the cosmic microwave background — light energy from the Big Bang that was scattered by protons and electrons existing during the early universe — still fills all of space.
Another reason interstellar and interplanetary space appear dark is that space is a nearly perfect vacuum. Recall that Earth’s sky is blue because molecules that make up the atmosphere, including nitrogen and oxygen, scatter a lot of visible light’s component blue and violet wavelengths from the sun in all directions, including toward our eyes.
- However, in the absence of matter, light travels in a straight line from its source to the receiver.
- Because space is a near-perfect vacuum — meaning it has exceedingly few particles — there’s virtually nothing in the space between stars and planets to scatter light to our eyes.
- And with no light reaching the eyes, they see black.
That said, a 2021 study in The Astrophysical Journal suggests that space may not be as black as scientists originally thought. Through NASA’s New Horizons mission to Pluto and the Kuiper Belt, researchers have been able to see space without light interference from Earth or the sun.
- The team sifted through images taken by the spacecraft and subtracted all light from known stars, the Milky Way and possible galaxies, as well as any light that might have leaked in from camera quirks.
- The background light of the universe, they found, was still twice as bright as predicted.
- The reasons for the additional brightness, which remain unknown, will be the focus of future studies.
Until then, one thing seems likely: Space could very well be more “charcoal” than pitch-black. Originally published on Live Science. Stay up to date on the latest science news by signing up for our Essentials newsletter. Tiffany Means is a meteorologist turned science writer based in the Blue Ridge mountains of North Carolina.
Which country is the closest to the Moon?
Mount Chimborazo, Ecuador Mount Chimborazo is the closest place on earth to the moon. This is because of a bulge on the earth where the mountain is located on, makes it the point closest to ‘outer space.’
Does the Moon have water?
The image shows the distribution of surface ice at the Moon’s south pole (left) and north pole (right), detected by NASA’s Moon Mineralogy Mapper instrument. Blue represents the ice locations, plotted over an image of the lunar surface, where the gray scale corresponds to surface temperature (darker representing colder areas and lighter shades indicating warmer zones). The ice is concentrated at the darkest and coldest locations, in the shadows of craters. This was the first time scientists directly observed definitive evidence of water ice on the Moon’s surface. Credits: NASA Is there water on the Moon? Actually, yes. But not like we experience here on Earth. On the Moon, water is found all over the surface, but it’s mainly in the form of ice and not pools of liquid water. Some places have more water than others. At the poles of the Moon are areas that never receive any sunlight, and so they’re extremely cold. We call these permanently shadowed regions, and there could be a lot of ice inside them. The ice inside these regions may be mixed in with the lunar soil, buried deep below the surface, or it could be a sheet of ice. Outside these extremely cold places is much less water, but it’s still there. Surfaces on the Moon that do see sunlight experience extreme temperature changes of 300 Celsius The Celsius scale, also known as the centigrade scale, is a temperature scale named after the Swedish astronomer Anders Celsius. In the Celsius scale, 0 °C is the freezing point of water and 100 °C is the boiling point of water at 1 atm pressure. ” data-gt-translate-attributes=””>Celsius, This makes it hard for water to survive on the sunlit Moon, but the water that does survive is unlike any water we experience here on Earth. But what does that mean? Imagine you have a handful of sand and you spread the grains of sand out so far that no grain touches another grain. An individual grain of sand represents a single molecule of water. And this is what we observe on the sunlit surface of the Moon. The sunlit Moon, however, has 100 times less water than the Sahara Desert, but the poles of the Moon may contain tons of ice. So, is there water on the Moon? Yes. And one day, future astronauts may be able to harvest this water and use it for drinkable water, breathable oxygen or rocket fuel to take us farther out into our solar system. Harvesting this water is a critical component of future human deep space exploration, which is why our VIPER rover will be traveling to the Moon’s South Pole to search for ice and other potential resources and determine where they came from. Is there water on the Moon? Yes! But you won’t find pools of liquid H2O on the lunar surface — water on the Moon is mostly in the form of ice. Harvesting this water is a critical component of future human deep space exploration, which is why our golf cart-sized VIPER, or the Volatiles Investigating Polar Exploration Rover, will be traveling to the Moon’s South Pole to search for ice and other potential resources to determine where they came from. Explore more about this first-of-its-kind rover. Credit: NASA Established in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. Its vision is "To discover and expand knowledge for the benefit of humanity." Its core values are "safety, integrity, teamwork, excellence, and inclusion." NASA conducts research, develops technology and launches missions to explore and study Earth, the solar system, and the universe beyond. It also works to advance the state of knowledge in a wide range of scientific fields, including Earth and space science, planetary science, astrophysics, and heliophysics, and it collaborates with private companies and international partners to achieve its goals. ” data-gt-translate-attributes=””>NASA
Is there a photo on the Moon?
A family photo – (c) NASA Apollo 16 astronaut Charles Duke left a framed family photo on the Moon’s surface. On the back it reads: “This is the family of astronaut Charlie Duke from planet Earth who landed on the moon on April 20, 1972.” Charles Duke was the youngest person to walk on the Moon, aged 36 in 1972.
How long is 6 trillion miles in years?
A light-year is the distance light travels in one Earth year. One light-year is about 6 trillion miles (9 trillion km).
How many years is 1,000 light-years?
How old would I be if I travelled 1000 light years in one year The answer is sort of trivial. If you travel 1000 ly so fast that in your own reference frame it takes one year, then you will have aged by one year in your own reference frame. To do so, you will need a speed of almost the speed of light, so in the reference frame of Earth, you will have spent just a tad more that 1000 yr to travel 1000 ly.
In general, the time dilation is given by the Lorentz factor $\gamma = 1/\sqrt $ so to be exact, your speed must be $$ 1000^2 = \frac ⇒ \\ v = (1-10^ )^ \,c = 0.9999995c $$ so your journey will take $$ t = \frac = 1000.0005\,\mathrm, $$ i.e.1000 years, 4 hours, and 23 minutes in Earth’s reference frame.
“Realistic” acceleration As David Hammen comments below, this assumes that your spaceship accelerates instantaneously to $v$. There are infinitely many ways to achieve that speed. The proper time $\tau$ (i.e. the time experienced by the traveler) to reach a distance $d$ when traveling at a constant acceleration $a$ is $$ \tau = \frac \cosh^ \left( \frac +1 \right).
- Solving for $a$ yields the acceleration needed.
- The most pleasant way would arguably be accelarating at $a\simeq 19.2\,\mathrm $ for half a year, and the decelerate at the same amount for the rest of the journey.
- A more pleasant way in the beginning, but less pleasant in the end, would be to accelerate at $a\simeq9.6\,\mathrm $ for one year, and then crash into planet WASP-142b, which lies at a distance of roughly 1000 ly.
Your journey, as measured by people on Earth, would then take $$ t(\tau) = \frac \sinh \left( \frac \right), $$ which works out to roughly 18 and 36 days more, respectively, than in the instantaneous case. The reason that it doesn’t differ that much is that you actually reach relativistic speeds pretty fast at this acceleration.
- The largest G-forces can be with endured in the “forward direction”, i.e.
- Corresponding to lying on your back and accelerating upwards (accelerating along the direction of your spine tends to break it, and accelerating “backward” makes your eyes pop out).
- According to Wikipedia, “acceleration pioneer” withstood 25 G for 1.1 seconds, so you might want to send him instead of yourself.
: How old would I be if I travelled 1000 light years in one year
Can we travel light-years?
Will Humanity Achieve Interstellar Travel And Find Alien Life? Although our dreams of making contact with an alien civilization have traditionally been rooted in, either a direct visitation or the picking up of an intelligent signal transmitted throughout the galaxy, these remain long-shot possibilities.
But real technology may enable us to find worlds where life is abundant and ubiquitous far sooner than we might have expected based on playing this cosmic lottery. Danielle Futselaar For as long as human beings have looked up at the stars in the sky, two questions have captured our collective imaginations: are there other life forms out there on any of their worlds, and will we ever realize the dream of traveling to one of them? Although both tasks appear to have enormously daunting technical challenges, recent advances in science suggest that not only might humanity be capable of overcoming them, but we might even do so later this century.
While faster-than-light travel and visitations from aliens — whether benign or malevolent — are staples of our science-fiction stories, it’s plausible that our real-life scientific advances may legitimately be more profound than any fictional stories humans have dreamed up.
- On the edge of both frontiers, humanity may be on the cusp of achieving a dream as old as humanity itself.
- A logarithmic chart of distances, showing the Voyager spacecraft, our Solar System and our nearest,
- Star, for comparison.
- If we ever hope to travel across the great interstellar distances, it will require a technology that’s superior to chemical-based rockets.
NASA / JPL-Caltech The biggest problem with the idea of interstellar travel is scale. The distances to even the nearest stars are measured in light-years, with Proxima Centauri being our nearest neighbor at 4.24 light-years away, where one light-year is approximately 9 trillion kilometers: some 60,000 times the Earth-Sun distance.
- At the speed of the fastest space probes humanity has ever sent on their way out of the Solar System (the Voyager 1 and 2 spacecraft), covering the distance to the nearest star,
- But all of this is based on current technology, which uses chemical-based rocket fuel for propulsion.
- The biggest downside of rocket fuel is its inefficiency: one kilogram of fuel is capable of generating just milligrams’ worth of energy, as measured by Einstein’s E = mc 2,
Having to carry that fuel on board with you — and requiring that you accelerate both your payload and the remaining fuel with that energy — is what’s hamstringing us right now. Position and trajectory of Voyager 1 and the positions of the planets on 14 February 1990, the day,
- When Pale Blue Dot and Family Portrait were taken.
- Note that it is only Voyager 1’s position out of the plane of the Solar System that enabled the unique views we retrieved, and that Voyager remains the farthest object ever launched by humanity, but still has thousands of times farther to go until it travels ~4 light-years.
Wikimedia Commons / Joe Haythornthwaite and Tom Ruen But there are two independent possibilities that don’t require us to dream up Warp Drive-like technologies that would rely on new physics. Instead, we can pursue the routes of either using a more efficient fuel to power our journey, which could increase our range and speeds tremendously, or we can explore technologies where the thrust-providing source is independent of the payload that’s going to be accelerated.
- nuclear fission,
- nuclear fusion,
- and matter-antimatter propulsion.
Whereas chemical-based fuels convert a mere 0.0001% of their mass into energy that can be used for thrust, all of these ideas are far more efficient. All rockets ever envisioned require some type of fuel. Whether a plasma engine, a matter/antimatter,
- Engine, nuclear-powered or conventionally powered, rockets all work on the same principle of thrust, but the efficiencies can vary enormously.
- NASA/MSFC Fission converts approximately 0.1% of the mass of fissile materials into energy; approximately one kilogram of fissionable fuel yields about one gram’s worth of energy, via E = mc 2,
Nuclear fusion does a superior job; fusing hydrogen into helium, for example, is 0.7% efficient: one kilogram of fuel would yield 7 grams’ worth of usable energy. But far-and-away the most efficient solution is matter-antimatter annihilation. If we could create and control 0.5 kilograms of antimatter, we could annihilate it at will with 0.5 kilograms of normal matter, creating a 100% efficient reaction that produced a full kilogram’s worth of energy.
We could conceivably extract thousands or even a million times as much energy from the same amount of fuel, which could propel us to the stars on timescales of centuries (with fission) or even just decades (with fusion or antimatter). An artist’s rendition of a laser-driven sail shows how a large-area, light-weight spacecraft could,
be accelerated to very high speeds by continuously reflecting back laser light that was high-powered and highly collimated. This could pose the most likely way that human beings have in their near-future arsenal of launching a macroscopic spacecraft over interstellar distances.
- Adrian Mann / UCSB On the other hand, we could work to achieve interstellar travel via a completely different route: by placing a large power source capable of accelerating a spacecraft in space.
- Recent advances in laser technology have led many to suggest could be used to accelerate a spacecraft from low-Earth orbit to tremendous speeds.
A highly reflective laser-sail, like a solar sail except specifically designed for lasers, could do the job. If a large-enough, powerful-enough array of in-phase lasers were constructed, potentially reaching gigawatt power levels, it could not only impart momentum to a target spacecraft, but,
Based on calculations, it’s possible that speeds up to 20% the speed of light could be reached. While we don’t yet have a plan for decelerating such a spacecraft, reaching the nearest star in a single human lifetime is within the realm of possibility. The laser sail concept, for a starchip-style starship, does have the potential to accelerate a,
spacecraft to about 20% the speed of light and reach another star within a human lifetime. It’s possible that, with enough power, we could even send a crew-carrying spacecraft to span the interstellar distances. Breakthrough Starshot By the same token, the search for extraterrestrial life is no longer restricted to either waiting for an alien visit or searching the Universe with radio signals for intelligent aliens, although the latter is certainly still an active scientific field spearheaded by SETI.
- Although no signals have been found, this remains a stunning example of high-risk, high-reward science.
- If a positive detection is ever made, it will be a civilization-transforming event.
- However, as exoplanet astronomy continues to advance, two techniques that have already been demonstrated could bring us our first signatures of life on other worlds: transit spectroscopy and direct imaging.
Both of these involve using the light from a planet itself, with transit spectroscopy leveraging the light that filters through a planet’s atmosphere and direct imaging taking advantage of the sunlight directly reflected off of the planet itself. When a planet transits in front of its parent star, some of the light is not only blocked, but if an,
atmosphere is present, filters through it, creating absorption or emission lines that a sophisticated-enough observatory could detect. If there are organic molecules or large amounts of molecular oxygen, we might be able to find that, too. at some point in the future. It’s important that we consider not only the signatures of life we know of, but of possible life that we don’t find here on Earth.
ESA / David Sing Transit spectroscopy relies on us having a serendipitous alignment of our observatory with both a target exoplanet and its parent star, but these alignments do occur. Whereas a small fraction of the star’s light will get blocked by the transiting planet, an even smaller fraction of starlight will transmit through the planet’s atmosphere, similar to the sunlight that gets transmitted through Earth’s atmosphere and lights up the Moon (in red) during a total lunar eclipse.
This enables us, if our measurements are good enough, to decode what elements and molecules are present in the target planet’s atmosphere. If we could discover biological signatures or even technosignatures which could be an oxygen-nitrogen atmosphere, complex biomolecules, or even something like a chlorofluorocarbon (CFC) molecule we would immediately have a strong hint of a living world that would tantalizingly await confirmation.
Left, an image of Earth from the DSCOVR-EPIC camera. Right, the same image degraded to a resolution, of 3 x 3 pixels, similar to what researchers will see in future exoplanet observations. NOAA/NASA/Stephen Kane Direct imaging could provide exactly that sort of confirmation.
- plant life greening with the seasons,
- rotation rates,
and much more. If there are light-emitting signatures at night, just as planet Earth has our light that illuminate the world at night, we could conceivably even detect those as well. If there’s a civilization out there on a nearby Earth-like planet, the next generation of telescopes might be able to find them.
The Earth at night emits electromagnetic signals, but it would take a telescope of incredible, resolution to create an image like this from light years away. Humans have become an intelligent, technologically advanced species here on Earth, but even if this signal were smeared out, it might still be detectable by next-generation direct imaging.
NASA’s Earth Observatory/NOAA/DOD All of this, together, points to a picture where a spacecraft or even a crewed journey to the stars is technologically within our reach, and where the discovery of our first world beyond the solar system with possible life on it could occur in a decade or two.
- What was once solely in the realm of science-fiction is quickly becoming possible due to both technical and scientific advances and the thousands of scientists and engineers who work to apply these new technologies in practical ways.
- On February 5 at 7 PM ET (4 PM PT), Dr.
- Bryan Gaensler, director of the Dunlap Institute for Astronomy and Astrophysics at the University of Toronto, at Perimeter Institute on exactly this topic.
Titled, it’s available to watch from anywhere on Earth, and I’ll be following along with a live-blog in real time, below. How close is humanity to achieving this dream that’s spanned innumerable generations? The answer is closer than you might think, so tune in here and follow along below (updates every 3-5 minutes) to find out what lies just beyond the known frontier.
It could be the revolution we’ve all been hoping for! Live blog begins at 3:50 PM Pacific Time, with all timestamps below shown beginning from that starting point. An illustration of the warp field from Star Trek, which shortens the space in front of it while, lengthening the space behind it. The Spore Drive, both in Star Trek and the idea of traversing through an extra spatial dimension in our reality, could take us from point A to point B even more quickly.
Trekky0623 of English Wikipedia 3:50 PM : Okay, warp drive fans, here we go! The first thing you might be wondering is about whether warp drive itself is really feasible or not. And the answer, believe it or not, is maybe, but not unless we figure out a source of energy that goes well beyond anything we’ve got so far, including antimatter.
- The reason is simple: to achieve warp drive, you need to bend the space in front of you so that it contracts, and that can only occur at the expense of expanding the space behind you.
- This takes an enormous amount of energy all localized in one spot, and you need to do it while still keeping the space where your spaceship will be not too severely bent, or you’ll wind up destroying it with terrific gravitational tidal forces.
The Alcubierre solution to General Relativity, enabling motion similar to warp drive. This solution, requires negative gravitational mass, which could be exactly what antimatter might provide. Wikimedia Commons user AllenMcC 3:54 PM : But if you can do it, and it is something allowed in General Relativity, this requires not only the matter-and-energy we know, but also some form of negative energy: either matter with negative mass or a form of anti-energy itself.
If we could harness this, it would mean we could travel through the contracted space (slower than light), but we could do something like contract a 40 light-year journey down to 6 light-months. Even if we only traveled through that now-contracted space at half the speed of light, we’d get there in 1 year, rather than 40.
That’s pretty impressive! The warp drive system on the Star Trek starships was what made travel from star to star possible. If, we had this technology, we could easily bridge the distance to the stars, but this remains in the realm of science fiction for today.
- dilithium crystals,
- warp nacelles,
- Bussard ramjets
- warp cores,
or anything else we might immediately refer to has any relevance. Science fiction provides us with possible outcomes, but only very rarely gets the path to that technological solution correct. We know enough about physics, today, to be certain that Star Trek’s “solution” to this problem is not feasible.
But, then again, that’s part of what makes science so wonderful: it can take a fictional idea and make it a reality. Or, if we’re really lucky, surpass our sci-fi dreams! A representation of an alien invasion. This is not an actual extraterrestrial. flickr user plaits 4:00 PM : Aliens, on the other hand, are likely ubiquitous, based on what we know about the ingredients for life in the Universe, the workings of chemistry, and our measurements of exoplanets with the right conditions for life around other stars.
We have literally billions and billions of potentially habitable planets in our galaxy alone, with similar conditions to early Earth. In many models, early Venus and Mars were similar to early Earth. Are we supposed to believe that Earth, where life arose within the first ~3% of our planet’s history, is somehow unique in that regard? Although winding up with something like human beings is a difficult proposition, winding up with no life at all, across billions and billions of other instances with similar initial conditions, seems far more unlikely, at least from a scientific perspective.4:01 PM : Hooray for another on-time start, as Greg Dick, the executive director of Perimeter Institute, gets us started right on time with his introduction! 4:02 PM : Oh, before I forget, Bryan is Australian, so get ready for an accent, although his won’t be the strongest Australian accent you hear by a long shot! 4:03 PM : And that’s a pretty quick introduction! Here we go; curious what the scientific perspective holds, according to an astronomer/astrophysicist who isn’t me! 4:05 PM : Spoilers: we don’t have warp drive yet, and we haven’t found the aliens yet.
Love to hear this up-front, but I also love the optimism that he has that science can make pretty much all of our non-laws-of-physics-violating dreams come true. I think, at its best, this is the dream we all have for science.4:07 PM : Bryan absolutely talks about an important aspect of being exposed to not just answers of what we do know, but what the frontiers of science are, what’s unknown, at a young age.
As a five year old, to discover that adults, parents, teachers, and even experts (libraries and encyclopedias) didn’t know the answer to everything. And that there are people who figure out the answers to those questions, and they’re just ordinary people, and that he could be one of them.
- Please note that this applies to everyone! You can do it, too, and you don’t have to figure that out at age 5 to do it.
- From inflation to the hot Big Bang, to the birth and death of stars, galaxies, and black holes, all,
- The way to our ultimate dark energy fate, we know that entropy never decreases with time.
But we still don’t understand why time itself flows forward. However, we’re pretty certain that entropy is not the answer.E. Siegel, with images derived from ESA/Planck and the DoE/NASA/ NSF interagency task force on CMB research 4:10 PM : And this is a lot of fun, too: the fact that questions we didn’t even know we needed to ask can be revealed by finding the answers to previous scientific questions.
In the 1920s, we didn’t know the Universe was expanding, but its discovery led to the idea of the Big Bang. In the 1960s, we didn’t know that the Big Bang was true, but its confirmation led to questions about what came before it and what our Universe’s ultimate fate would be. And now, as you can see, we’re talking about the mysteries of cosmic inflation and dark energy, which are where those frontiers now lie.
And in any field, this is how it works: discovering an answer only reveals a deeper frontier that we haven’t yet explored.4:11 PM : I like Bryan’s delineation between the difference between science and science fiction. Science is all about discovering and following the rules; science-fiction is about breaking those rules.
- I haven’t explicitly thought about it in those terms, and I agree that this is pretty much how it usually works.
- I don’t know that this is why I, personally, like or don’t like various forms of science-fiction, but it’s a new perspective to think about for me.4:13 PM : We constantly have advancing technology, and science-fiction asks the question of how advancing technology will change our lives.
He brings up the example of Westworld, which I like, but I really think he missed a golden opportunity to reference Black Mirror, which really highlights and elevates the dystopian aspects of our society in a new way in each episode. An animation showing the path of the interstellar interloper now known as ʻOumuamua.
- The combination,
- Of speed, angle, trajectory, and physical properties all add up to the conclusion that this came from beyond our Solar System.
- NASA / JPL – Caltech 4:15 PM : Alright, some science! Here we are, moving on to interstellar interloper ‘Oumuamua, one of the things we’ve seen that wasn’t particularly anticipated, even by science fiction.
And yet, Bryan is correct to point out that Star Trek IV: The Voyage Home, had a cigar-shaped alien asteroid in our own solar system. It’s not, of course, telling us to save the whales, and it’s not a space probe, but it’s remarkable that science fiction had this idea before astronomers or any scientists knew it was coming.
The Event Horizon Telescope’s first released image achieved resolutions of 22.5 microarcseconds,, enabling the array to resolve the event horizon of the black hole at the center of M87. A single-dish telescope would have to be 12,000 km in diameter to achieve this same sharpness. Note the differing appearances between the April 5/6 images and the April 10/11 images, which show that the features around the black hole are changing over time.
This helps demonstrate the importance of syncing the different observations, rather than just time-averaging them. Event Horizon Telescope Collaboration 4:18 PM : This one is a little bit less fair. When you’re talking about older movies that talk about black holes, it’s really unfair to talk about how “we knew what black holes would look like” in science-fiction, because black holes have been astrophysically theorized for decades, going back to the 60s, 50s, or even 1916 in the context of General Relativity, and even earlier (the late 18th century) in Newtonian gravity.
Sure, it’s fascinating, but visualizations, based on a mix of science and artistic license, have been around for as long as we’ve even known enough about science to imagine what could realistically be. Also, side note, the “interstellar” black hole is probably not very likely to be what we see when we examine our realistic black holes in supreme accuracy; there’s a lot of artistic license and some likely unphysical assumptions that were made for Insterstellar.
Artist’s illustration of two merging neutron stars. Binary neutron star systems inspiral and merge, as well, but the closest orbiting pair we’ve found within our own galaxy won’t merge until nearly 100 million years have passed. LIGO will likely find many others before that.
- NSF / LIGO / Sonoma State University / A.
- Simonnet 4:22 PM : I also don’t quite think it’s fair to say “well, we simulated and visualized this astrophysical event,” and then “we observed it,” and “that’s an example of science outstripping science fiction.
- Yes, it’s true that the entire Universe shook.
but not every scientific event, including one that involves planet Earth “shaking” by less than an atom’s width, makes for particularly good science fiction. He said earlier, remember, that science fiction was about investigating the human condition. It’s hard to see how a tiny, subtle effect like that would make for a good sci-fi story.
The hyperdrive from Star Wars appears to depict an ultra-relativistic motion through space,, extremely close to the speed of light. Under the laws of relativity, you neither reach nor exceed the speed of light if you’re made of matter. But you might be able to approach it if you had a large-enough amount of an efficient-enough fuel.
Dark matter could fit exactly the conditions we need to make this science-fiction dream a reality. Jedimentat44 / flickr 4:25 PM : Okay, this is a pet peeve of mine. Do you know why things like rockets and space shuttles have the shapes they do? That elongated, narrow-cone shape you’re familiar with? It’s because of atmospheric drag.
If you’re going to build your ship in space, and fly it only in space, you don’t need to factor in aerodynamic considerations at all! You’d be much, much smarter to build a structure with a good volume-to-surface-area ratio: a sphere. The Death Star, not the Millennium Falcon or an X-Wing, is going to be much more practical for structures we build in space! The NEXIS Ion Thruster, at Jet Propulsion Laboratories, is a prototype for a long-term thruster that,
could move large-mass objects over very long timescales. NASA / JPL 4:28 PM : Ion drives are real, and they’re very cool. But if you want to power a journey across large distances in a reasonable amount of time, ion drives won’t get you far at all. They can take you ~6 billion kilometers over 11 years, as Bryan said, and can do so pretty efficiently.
But if you factor that distance over that time as a “mean acceleration,” you get something truly atrocious: 100 nanometers/second^2. You’re. not going to go very far very fast. ~100,000 years to the nearest star, same as conventional fuel. I’ll pass, thank you. Normally, structures like IKAROS, shown here, are viewed as potential sails in space.
However, if a, large-area object were placed between the Earth and the Sun, it could reduce the total irradiance received at the top of our atmosphere, potentially combating global warming. Wikimedia Commons user Andrzej Mirecki 4:30 PM : Hey, solar sails! Yes, if you accelerate with a solar sail, you can decelerate with a solar sail! The “fuel” is simply radiation provided by a star, so as long as you visit a star comparable to the Sun, you could decelerate the same way you accelerated.
Unfortunately, this technology is inferior to ion drives not only in terms of distance reached, but in terms of acceleration and control over your spacecraft. It’s a nice idea, but it’s an idea that’s in its infancy, at best, despite being proposed more than 400 years ago by Johannes Kepler! 4:32 PM : 75 years?! That’s.
that’s going to assume a very light payload and a very, very large and efficient over a distance of 1.8 kilometers. Can we do that for ~4 light years, or 20 trillion kilometers. That’s. well, good luck is all I’ll say. The EmDrive device, as originally displayed by Roger Shawyer’s company, SPR Limited.
- SPR Limited 4:33 PM : Hey, don’t be out of date, Bryan! The Em Drive,
- Nice idea, but it’s done.
- Quantum teleportation, an effect (erroneously) touted as faster-than-light travel.
- In reality, no,
- Information is being exchanged faster than light.
- However, the phenomenon is real, and in line with the predictions of all viable interpretations of quantum mechanics.
American Physical Society 4:36 PM : Remember, what “quantum teleportation” is doesn’t involve teleporting a particle, it involves teleporting the quantum state of a particle. And Bryan gets that right, but this doesn’t solve the problem of teleporting an inanimate object, much less a person.4:38 PM : Yes, you need a lot of information to encode a human being.
- Remember that there are around ~10^28 atoms in the human body, and that means something like 10^29 or 10^30 quantum bits of information.
- As Bryan says, “I don’t think we’ll be teleporting anytime soon.” The travel time for a spacecraft to reach a destination if it accelerates at a constant rate of,
Earth’s surface gravity. Note that, given enough time, you can go anywhere.P. Fraundorf at Wikipedia 4:40 PM : Hey, don’t be mad at time dilation! Time dilation is what could get us to the stars in a human lifetime. If you wanted to go more than ~100 light-years, it would always take you more than ~100 years (a human lifetime, at the far end) to get there from the frame-of-reference of a person remaining on Earth.
But if you continue to accelerate at 1 g, or 9.8 m/s^2, you’ll get to wherever you want to go in a much shorter timescale from your frame of reference, as you travel close to the speed of light. Time dilation rules! An artist’s conception of a starship making use of the Alcubierre drive to travel at apparently,
faster-than-light speeds. By combining warp technology with the mycelium drive and the ship’s shields, Stamets and Tilly devise a plan to get Discovery home while keeping the mycelium network intact. NASA 4:42 PM : Okay, really? From long, long-term technologies like ion drives and solar sails straight to warp drive, with nothing in between? In terms of not using fuel, Bryan is correct.
But in terms of not using energy. well, good luck transforming your spacetime, where (reminder) spacetime’s curvature is based on matter-and-energy, without expending energy! The DEEP laser-sail concept relies on a large laser array striking and accelerating a relatively, large-area, low-mass spacecraft.
This has the potential to accelerate non-living objects to speeds approaching the speed of light, making an interstellar journey possible within a single human lifetime. The work done by the laser, applying a force as an object moves a certain distance, is an example of energy transfer from one form into another.
© 2016 UCSB Experimental Cosmology Group 4:43 PM : Wait, he’s going to finish this part of his talk now, talking about Breakthrough Starshot (and the laser sail technology and a “starchip” spaceship) which we mentioned earlier, and cover “aliens” in. what, 10-15 minutes? We’ll see! 4:45 PM : Nope; we’re not onto the “aliens” part yet; we’re talking about femtosatellites, which are still quite large and weigh a few grams, which is still too much for Breakthrough Starshot.
Tiny particles known as micrometeoroids will strike whatever they encounter in space, causing, potentially very significant amounts of damage as a result, especially as the collisions build up over time and occur at higher speeds. NASA; Secure World Foundation 4:48 PM : Yesss! This is something I’m excited to hear, because it’s something that I’ve brought up that few people talk about: when you travel through space at relativistic speeds, you are going to smash into stuff in the interstellar medium! And that stuff is going to erode your spacecraft really fast, and there’s nothing that’s going to protect your “starship” (even if it’s a microchip) from smashing into that dust.
- Remember that a little piece of nerf-like foam was all it took, at high speeds, to cause the Space Shuttle Columbia disaster.
- Remember that all of our spacecraft get hit by micrometeoroids.
- And remember that 20% the speed of light is about 100 times faster than our fastest spacecraft go, which means they have 10,000 times the kinetic energy from dust particle collisions.
This is a harder problem to overcome than anyone has figured out a viable way to reckon with.4:50 PM : Okay, it’s onto the aliens part, and I have to disagree with what Bryan says. We don’t want to go to planets around other stars to look for life; we want to find planets where life exists (or is likely) and then go there.
There are ~400 billion stars in our galaxy. Do you want to go on a wild goose chase, or do you want to know where you’re going before you go on a decades-long journey across the great void of space? (Pick the latter.) When Hubble pointed at the system Kepler-1625, it found the initial transit of the main planet began,
an hour earlier than anticipated, and was followed by a second, smaller transit. These observations were absolutely consistent with what you’d expect for an exomoon present in the system. NASA’s Goddard Space Flight Center/SVS/Katrina Jackson 4:53 PM : Using the transit method, we can find out properties of the planets that orbit around the stars, and they come in enormous varieties, just like we’d expect if we didn’t assume the rest of the Universe was just like our little corner.
- We’ve found the planets that are easiest to find, and that means the largest planets relative to their star in close-in orbits.
- This, unsurprisingly, has skewed the population of planets that we’ve found.
- Although more than 4,000 confirmed exoplanets are known, with more than half of them uncovered by,
Kepler, finding a Mercury-like world around a star like our Sun is well beyond the capabilities of our current planet-finding technology. As viewed by Kepler, Mercury would appear to be 1/285th the size of the Sun, making it even more difficult than the 1/194th size we see from Earth’s point of view.
NASA/Ames Research Center/Jessie Dotson and Wendy Stenzel; missing Earth-like worlds by E. Siegel 4:55 PM : We have found waterworlds and lava worlds, but these are. well, likely not the best candidates for an “interesting” form of alien life. Nor are hot Jupiters (or any type of Jupiter), or any gas planet with a large hydrogen/helium envelope.
Just like in our own Solar System, most of the planets out there are not expected to have life on them.4:56 PM : This is a totally unimportant point, but for an astronomer, it’s a pet peeve for many. The smallest stars in the Universe are red dwarfs. Always dwarfs, never dwarves.
The plural of dwarf (for stars) is dwarfs; the plural of dwarf (for the fantasy race of short, stout, beard, axe-wielding characters) is dwarves. If TOI 700d were a cloudless, dry-land planet with an atmosphere similar to modern Earth, there, would be a ring of potential habitability with Earth-like temperatures and atmospheric pressures near the border between the eternal day/night sides, where the winds always flow from the night side to the day side.
Engelmann-Suissa et al./NASA’s Goddard Space Flight Center 4:59 PM : This is also an important point: what’s happening on a world around a red dwarf star isn’t so much about the irradiance from the star and day/night temperatures and the border between them, but how the atmosphere circulates and what it’s composed of.
We also have to be very careful in distinguishing between “biosignatures,” which is going to be a slam-dunk signal that tells us, “wow, that’s a living planet right there,” and a “bio-hint,” which is what Bryan’s referring to, which is pretty much guaranteed to get you false positives, over and over, before you actually get it right.
This diagram shows the novel 5-mirror optical system of ESO’s Extremely Large Telescope (ELT). Before reaching the science instruments the light is first reflected from the telescope’s giant concave 39-metre segmented primary mirror (M1), it then bounces off two further 4-metre-class mirrors, one convex (M2) and one concave (M3).
The final two mirrors (M4 and M5) form a built-in adaptive optics system to allow extremely sharp images to be formed at the final focal plane. This telescope will have more light-gathering power and better angular resolution, down to 0.005″, than any telescope in history. ESO 5:01 PM : This is really true: the ELT will be humanity’s best chance, in the 2020s, for directly imaging an Earth-like (or potentially inhabited) planet of any type.
This could lead us to a revolution, where bio-hints and bio-signatures could be abundant. Right now, planet-finders like TESS are giving us the best candidate planets for direct imaging, and while we’ll have to get lucky, this is the high-reward science most of us dream about! In this artist’s rendition, NASA’s Clipper spacecraft makes one of its many dozen close passes to,
Europa, the most likely candidate for life in the Jovian system to date. With all the ingredients it possesses and the conditions as we know them on this world, Europa might be the most life-friendly world beyond Earth presently known to humanity. However, in order to know whether there’s life in Europa’s sub-surface ocean, we’ll have to probe down beneath its enormously thick crust that’s some 15+ kilometers thick.
NASA/JPL-Caltech 5:04 PM : Of course, this is the third possibility I haven’t discussed for finding life: it could be right here in our Solar System! Do we have life in a subsurface ocean on Europa or Enceladus? Do we have subterranean, potentially seasonally active/inactive life on Mars? Do the outer worlds, like Triton or Pluto, have anything on them of interest? We have missions going to look, and hopefully in the 2020s, we’ll start to get answers that teach us whether our fantastical interpretations of signals like seasonal methane or organic molecules really hold up.
- They could be biotic in nature, and we won’t know until we do the appropriate tests! A small section of the Karl Jansky Very Large Array, one of the world’s largest and most powerful,
- Arrays of radio telescopes.
- The radio capabilities of this array, in terms of resolution and sensitivity, place it among the top 2 or 3 arrays in the entire world.
John Fowler 5:06 PM : This is a fun fact: you must not use a walkie talkie around radio telescopes; the interference is atrocious! Remember that people didn’t know what “fast radio bursts” were for much longer than we realized, because the microwave oven in the break room of a giant radio telescope was causing interference? That’s a true story; don’t use walkie talkies near radio telescopes! 5:07 PM : So I think this 1 hour talk has taught me how you talk about two topics when you spend the first 50 minutes on the first topic: just keep talking over your talk’s time! 5:10 PM : The present and the near future are incredibly exciting, and you don’t need warp drive or actual aliens to make it so.
But, that said, it would be pretty cool to achieve interstellar travel or to find any true signatures (not just hints + wishful thinking) of alien life. This is why we do science and why we develop technology; these are our sci-fi dreams and we’re making them come true! 5:12 PM : Alright, talk’s over and we’re into the Q&A.
Hey, and the first question is “how do we go from that light of an exoplanet transiting” to “how do we extract all that useful information?” And the two answers are:
- transit spectroscopy, and
- direct imaging.
Bryan is only giving the first answer, but both matter! 5:14 PM : No to aliens in Roswell, New Mexico. Good answer, Bryan. I like the snark of, “why come all this way just to dissect a cow?” Alright, everyone, that’s all the time I’ve budgeted for today’s talk; hope you enjoyed the live blog and Bryan’s talk! We might not have found aliens yet and we might still be quite far from reaching another star, but our technology has brought us quite an impressive way already, and we’re headed towards something even more spectacular as the 2020s begin to unfold.
Does water freeze in space?
Space is cold, but it doesn’t itransfer heat very well so the liquid cannot freeze unless it simultaneously boils. It sounds crazy but there it is. It will boil, lowering it’s temperature, it will freeze, increasing it’s temperature, and keep on untill it is a haze of snow and ice.
Can it be hot in space?
- Science & Astronomy
(Image credit: Getty Images) Though sci-fi movies would have us believe that space is incredibly cold — even freezing — space itself isn’t exactly cold. In fact, it doesn’t actually have a temperature at all. Temperature is a measurement of the speed at which particles are moving, and heat is how much energy the particles of an object have.
What planet takes 7 years to get to?
6. Saturn, 7 Years (Cassini) – Cassini took the better part of a decade to make the trip, launching in 1997 and landing in 2004. It saw most of the planets in between, and used Jupiter’s gravity to make the final push. Interestingly it wasn’t alone, and carried the Huygens lander, which successfully landed on Saturn’s moon Titan.
How long is trip to Mars?
This shows an artist’s concept animation of the Perseverance cruise stage cruising to Mars. DISTANCE TRAVELED Loading. Loading. miles / km DISTANCE REMAINING Loading. Loading. miles / km The cruise phase begins after the spacecraft separates from the rocket, soon after launch.
- The spacecraft departs Earth at a speed of about 24,600 mph (about 39,600 kph).
- The trip to Mars will take about seven months and about 300 million miles (480 million kilometers).
- During that journey, engineers have several opportunities to adjust the spacecraft’s flight path, to make sure its speed and direction are best for arrival at Jezero Crater on Mars.
The first tweak to the spacecraft’s flight path happens about 15 days after launch.
How long does it take to get to Venus?
The shortest time a spacecraft has taken to get to Venus from Earth is 109 days, or 3.5 months. The longest journey took 198 days or 6.5 months. Most journeys take between 120 and 130 days which is about 4 months.