What's the coolest fact you know about space?

October 30, 2022 10:05 AM

I'm in need of some interesting facts about outer space. The more off-the-wall the better, but don't let that limit you. Is there a space fact that's made your brain melt?
posted by Charity Garfein to Science & Nature (35 answers total)

Remember the static on old TV sets? A substantial part of that is caused by leftover radiation from the Big Bang.
posted by Blue Jello Elf at 10:16 AM on October 30, 2022 [13 favorites]

Question: Which would be brighter, as defined by the amount of energy that would go through your eyeball?

1) The sun going supernova at its current distance of 93 million miles (Our sun isn't the right type of star and can't go supernova, but work with me here.)

2) A nuclear bomb, pressed up against your eyeball

The answer is that the supernova would be about a billion times brighter than the nuclear bomb.
posted by Hatashran at 10:24 AM on October 30, 2022 [4 favorites]

Neutron stars are really dense. As the Flaming Lips song goes, a spoonful weighs a ton, or actually closer to 6,000,000,000 tons (that's mass, the weight is much higher in the intense gravitational field)
posted by credulous at 10:29 AM on October 30, 2022 [1 favorite]

Astronauts outside of low earth orbit often see flashes of light that are hypothesized to be cosmic rays interacting with their eyeballs, retinas or visual cortex: Cosmic ray visual phenomena.
posted by the Real Dan at 10:35 AM on October 30, 2022 [2 favorites]

Best answer: If stars were the size of wasps, and were distributed with the same density as they exist in the Milky Way, the continent of Europe would contain seven wasps.

You can fit all the planets in the solar system between earth and the moon.

Space is really empty.
posted by caek at 10:36 AM on October 30, 2022 [7 favorites]

Parts of outer space smell like raspberries!!!
posted by Ausamor at 10:36 AM on October 30, 2022 [2 favorites]

Everything is sliding toward The Great Attractor
posted by effluvia at 10:43 AM on October 30, 2022

The moon's albedo is only .12, meaning it absorbs 88% of the light hitting it. It's actually really dark, like a lump of coal or old asphalt in space.
posted by los pantalones del muerte at 10:54 AM on October 30, 2022 [7 favorites]

The magnetic field from a magnetar (a super-magnetic neutron star) is so powerful that it would basically make all the atoms in your body come apart from each other.
posted by number9dream at 10:56 AM on October 30, 2022

Mr. Sun was photographed smiling recently.
posted by SPrintF at 10:57 AM on October 30, 2022 [6 favorites]

Best answer: The rings of Saturn are relatively new, geologically speaking. Between 10 million and 100 million years old. They may be younger than the dinosaurs.
posted by explosion at 11:13 AM on October 30, 2022 [3 favorites]

Less awesome but funny is the summary of wavelengths combined makes the mean colour of the universe beige, depending on how you look at it.
posted by ovvl at 11:46 AM on October 30, 2022 [2 favorites]

If you hold your hand up to the sky, there are more stars behind your hand than there are grains of sand on all the beaches of the earth.
posted by BlahLaLa at 11:59 AM on October 30, 2022 [4 favorites]

Spaghettification. I heard about this years ago at a planetarium show and the imagery just stuck with me. Theoretically, if you were falling toward a black hole, your body would begin to stretch and compress until you were long and thin like a spaghetto.
posted by kbar1 at 12:22 PM on October 30, 2022

The star Stephenson-2 is so large that if it was placed in the center of our solar system its edge would extend beyond the orbit of Saturn.
posted by Winnie the Proust at 12:36 PM on October 30, 2022

Not awesome but also probably only amusing to me is the blazar, which is a quasar pointed at the observer, mainly because that’s my first initial and last name.
posted by billsaysthis at 12:50 PM on October 30, 2022 [1 favorite]

On venus, it rains sulfuric acid, but the raindrops evaporate before they hit the ground. This exact sentence is also a song lyric
posted by Ardnamurchan at 12:59 PM on October 30, 2022

Space-time
posted by aniola at 1:37 PM on October 30, 2022

45 years after their launch, Voyager 1 and 2 are still working and sending data from interstellar space (albeit very, very slowly).
posted by Stoneshop at 1:55 PM on October 30, 2022 [5 favorites]

You won't instantly freeze to death in space! (I mean, you'll totally die, but not of that; it's more of a suffocation deal.) If the sun is shining on you, you might actually never freeze, but even in deep space it takes hours, because even though space is technically cold, there's no atmosphere for your body heat to conduct away through. Think about the difference between damp cold and dry cold; space is basically the dryest cold imaginable.
posted by Nibbly Fang at 2:22 PM on October 30, 2022

I'm not sure I totally understand how space itself can expand faster than the speed of light in space but I think it qualifies as interesting, maybe weird, bordering on brain melting.
posted by forthright at 2:22 PM on October 30, 2022 [1 favorite]

Everyone knows that galaxies look small because they are so far away. But, beyond a certain distance they look larger again because the Universe that long ago was so much smaller so they took up a bigger part of the sky!
posted by vacapinta at 2:25 PM on October 30, 2022 [7 favorites]

Some facts from the astronomy section of my blog (link in profile):

• Mercury is, on average, the closest planet to every other planet in the solar system.
• The first three artificial satellites fell back into the atmosphere within a year of their launch, but the fourth - Vanguard I, in 1958 - is still orbiting today.
• Vesta, an asteroid / proto-planet in the asteroid belt, has the highest mountain in the solar system.
• Phobos, a moon of Mars, is thought be a "rubble pile." Under the surface, it is estimated to be between a quarter and a third empty space.
• The oldest dated Earth rock - Big Bertha - was found on the Moon.
• Gherman Titov, the second person in space, was the first person to sleep in space, the first person to manually pilot a spacecraft, and the first person to throw up in space.
• It's difficult to freeze in space, but the atmospheric pressure is so low that any exposed moisture (saliva, sweat, pee) will immediately boil - including the liquid that coats the alveoli of our lungs.

posted by Paragon at 2:32 PM on October 30, 2022 [3 favorites]

Cleopatra lived closer in time to the moon landing than to the building of the Great pyramids.
posted by CathyG at 8:17 PM on October 30, 2022 [1 favorite]

I just learned that it's actually pretty hard to launch someone into the sun from earth, compared to slinging them away from it.
posted by aspersioncast at 8:28 PM on October 30, 2022 [1 favorite]

Apollo Moonwalkers Triv Quiz.

1. Who was the last man on the Moon?
2. Who was the last man off the Moon?
3. Who blew up the colour TV camera by pointing it at the Sun? Ooops
4. Who made the most precise landing (and retrieved parts from a previous unmanned probe)
5. Who was the youngest Moon-walker?
6. Who used a 6-iron?
7. Who died first and youngest?
8. Who believes in faith-healing and UFOs?
9. Who was the first person to drive on the Moon?
10. Who brought back the largest lump of Moon-rock?
11. Who took communion and brought the chalice back ?

Answers

1. Jack Schmitt (Apollo 17; the only professional scientist (geology) and the only civilian Moon-walker)
2. Eugene Cernan (Apollo 17; as mission captain he was first on, last off)
3. Al Bean (Apollo 12; he was a painter)
4. Pete Conrad (Apollo 12; check him out, more interesting than some of the others)
5. Charles Duke (Apollo 16; he was 36 his mission commander was called Young)
6. Alan Shepard (Apollo 14; Shepard whacked a tuthree golf balls into the middle distance. He was also the oldest Moon-walker (47 at the time), having been 38 when he became the first American in space - he went up and down in a parabola, John Glenn went into orbit.  )
7. James Irwin (Apollo 15; he was 61 when he had a heart-attack in 1991 becoming the first of the Moon-walkers to die.)
8. Edgar Mitchell (Apollo 14; he was cured of renal cancer by remote and knows that aliens are talking to (some of) us)
9. Dave Scott (Apollo 15; he could also drive a hard bargain: he hatched a cunning plan to take 398 commemorative stamped envelopes to the Moon and back to sell for profit.  Current price for such a Sieger Cover is $15,000.  They say that Alan Shepard did a similar deal with medals from the Franklin Mint on the Apollo 14 mission).
10. John Young (Apollo 16; I can't find anything more interesting to say about this man)
11. Buzz Aldrin (Apollo 11; the chalice is used by Aldrin's pastor back home on the Sunday nearest 20 July - today for example)

posted by BobTheScientist at 12:30 AM on October 31, 2022

The Andromeda galaxy. In about five billion years, it will be merging into the Milky Way, and eventually that will result in a new galaxy. You will often see assertions that they will "collide," but collision suggests destruction, and it is most likely that there will not be much if any effect on the stars contained in either galaxy as they merge. That is how far apart stars are.
posted by yclipse at 11:07 AM on October 31, 2022 [3 favorites]

The relative distances of the sun and the moon are such that they appear almost exactly he same angular size to us. Due to the fact that the orbits are slightly elliptical sometimes the moon is he larger of the two and sometimes the smaller. Sa far as anybody knows, this is entirely confidential since the moon is and has been moving steadily away from the earth at about the speed that hair grows. That’s pretty slowly, but the moon used to be much closer. Earth’s tides steadily transfer its angular momentum to the moon, boosting it, lengthening the day and shortening the month. Nevertheless, the moon’s current orbit would fit neatly inside the sun.
posted by sjswitzer at 6:20 AM on November 1, 2022

(Oops: lengthening both the day and the month)
posted by sjswitzer at 6:27 AM on November 1, 2022

Folks have spoken to the vastness of the universe in terms of space, but this video shows how breathtakingly vast it is in terms of time, too.

(Fair warning, I watched this video and thought it was absolutely beautiful how long the universe will be doing incredible things; my partner watched it and wept for how infinitesimal a part of it we play and how soon we must vanish.)
posted by solotoro at 6:41 AM on November 1, 2022 [1 favorite]

Reposting (with slight editing) two things I said in a previous AskMe:

The moon technically doesn't revolve around the Earth. It's more accurate to say that the Earth-Moon system has a barycenter which is the center of mass for these two bodies. (Imagine a grown person swinging a small child in a circle and you get the idea, the center of the rotation will probably be between the two.) In our particular case, the Earth is massive enough compared to the moon that the barycenter is still located about 1000 miles under the Earth's crust, but away from the Earth's core. By comparison, Pluto and Charon are much closer in mass, so their barycenter is located between the two.

The Sun is much more massive, but the aggregate mass of the planets acting on it causes the barycenter to get real wobbly, in fact the barycenter has spent most of the past 75 years outside of the surface of the sun, and will reach one of its furthest distances from the Sun's center in 2023. This is actually one of astronomers' main tools to infer the existence of planets around other stars -- watching carefully for small wobbles in their orbits caused by planets.

and

while we're on an astronomy kick I'm going to steal this one from Randall Munroe:

"The reason it's hard to get to orbit isn't that space is high up. It's hard to get to orbit because you have to go so fast[...]

Space is about 100 kilometers away. That's far away—I wouldn't want to climb a ladder to get there—but it isn't that far away. If you're in Sacramento, Seattle, Canberra, Kolkata, Hyderabad, Phnom Penh, Cairo, Beijing, central Japan, central Sri Lanka, or Portland, space is closer than the sea.[...] You could get a person to space with a small sounding rocket the size of a telephone pole. The X-15 aircraft reached space just by going fast and then steering up.

But getting to space is easy. The problem is staying there.

Gravity in low Earth orbit is almost as strong as gravity on the surface. The Space Station hasn't escaped Earth's gravity at all; it's experiencing about 90% the pull that we feel on the surface.

To avoid falling back into the atmosphere, you have to go sideways really, really fast. The speed you need to stay in orbit is about 8 kilometers per second. Only a fraction of a rocket's energy is used to lift up out of the atmosphere; the vast majority of it is used to gain orbital (sideways) speed."

posted by The Pluto Gangsta at 9:58 AM on November 1, 2022 [2 favorites]

I just saw this today, in a story about the recent Dart mission which struck the asteroid Dimorphos (in LRB 10/20/2022 p. 27):

"Modern estimates ... suggest a flux of ten (micrometeorite) particles per square meter (on Earth) per year ... unless you have cleaned your gutters recently, they probably harbor a few motes of extraterrestial dust."
posted by JonJacky at 8:39 PM on November 1, 2022

"The moon technically doesn't revolve around the Earth. It's more accurate to say that the Earth-Moon system has a barycenter which is the center of mass for these two bodies."

Under this reading, does anything other revolve around anything else, other than a black hole?
posted by benbenson at 11:21 AM on November 3, 2022

Well, two bodies of mass will always have a barycenter, but for a lot of things its a totally negligible difference.

Like, all of the satellites orbiting the Earth right now could, in theory, have an aggregate mass that moves the center of rotation a fraction of a fraction of a meter away from the center of the Earth, but who notices?

In the case of a black hole, it's just so massive (and dense) that hardly anything would affect it, except another black hole. In fact, two black holes caught in a spiraling orbit around each other was essential to the Laser Interferometer Gravitational-Wave Observatory (LIGO) that made headlines a few years ago when its observations supported Einstein's theory of gravity waves.
posted by The Pluto Gangsta at 11:55 AM on November 3, 2022

Also, here's an interesting bonus fact: While those two black holes are spiraling towards each other, the Earth/Moon system is different in that the Moon is actually slowly moving away from us all the time, at an average yearly rate that's about equal to the rate your hair grows.
posted by The Pluto Gangsta at 12:00 PM on November 3, 2022