/r/spacequestions

Photograph via snooOG

SpaceQuestions is a subreddit for asking questions about astronomy, rocketry, astrophysics and cosmology. We welcome everyone to post questions to satisfy their curiosity and further their scientific understanding. Our most common questioners fit into two categories: the scientifically curious, and fiction authors wanting to add realism into their stories. Please be courteous in your replies and help everyone to learn more about space together.

Welcome to /r/spacequestions, a subreddit dedicated to knowledge about space. Do you have questions about or related to space? This is the place for answers!

All questions about space are welcome here, from the simple to the complex. Do you have questions about astronomy? Launch vehicles? Space agencies? Space science? All is welcome.

Anyone may answer a question, though we ask that you try to be accurate.

The rules:

  • All posts must be a question about space. This includes astronomy, space science, space launch systems... anything related to space! Posts that do not follow this rule will be removed.

  • Self posts only. If you have a question about an image, please link to it in your self post.

  • Avoid memes or jokes in self-posts, and do not post them as top level comments. Such comments may be removed.

  • Avoid baseless speculation.

  • Be nice to each other.

Related subreddits:

/r/space

/r/spaceflight

/r/spaceporn

/r/ImaginaryStarscapes

/r/spacex

/r/jupiters

/r/newhorizons

/r/spaceweather

See also the Small Space Subreddits MultiReddit.

/r/spacequestions

7,745 Subscribers

1

Hi yall! Whats your fav messier object?

Mineis the medusa merger, eagle nebula and the omega nebula!

0 Comments
2024/12/01
09:15 UTC

1

Satellite???

I’m in Panama City beach and I have seen like tons of satellites pass over us, but spread out, is it starlink? Or something else?

4 Comments
2024/11/29
00:02 UTC

4

Satellite question

I skywatch very often. I've seen countless satellites and have seen Starlink pass over my house twice. But this morning I saw something new that made me curious. I saw an extremely long string of lights traveling due east. There were at least 100 of them and it took at least 20 minutes to pass. All appeared to be the same distance from each other. As I said above, l've seen Starlink, and it didn't look anything like that. It could be something common that l've never seen. I'm hoping someone could satisfy my curiosity.

5 Comments
2024/11/27
12:22 UTC

2

Kessler syndrome question

I heard about Kessler syndrome a while back and was wondering if sending a satlite up with a magnet to drop the debris back down to earth as small asteroids would be a possible or helpful

4 Comments
2024/11/17
03:58 UTC

2

Comet/Meteor question

Hi, about 5 years ago I saw a comet/meteor in the night sky and never really questioned it. The most memorable part was it started off as a slightly green looking shooting star then got really bright in a brownish colour and the tail changed directions. My questions are why did its shine turn brown suddenly and what made the tail/trail change directions.

Thanks for your time.

4 Comments
2024/11/16
10:15 UTC

3

Elliptical orbits

All of the planets in our solar system have elliptical orbits. Do the ellipses share a common major axis, or are they positioned randomly?

6 Comments
2024/11/14
20:24 UTC

2

Voyager 1 & 2 distance from earth in light years?

How far in light years has Voyager 1 or 2 or both, traveled from earth? Instead of a percentage or miles could you break this down into days and hours? Example answer; Voyager 1 has traveled approximately 1d 14h 37m 28s of 1 light year. Hope this makes sense. Sorry I'm no great mathematician. I figured it to be approximately 8h 45m, could this be correct? They were launched in '77 and have went just 9hours of a light year? Again sorry I'm having trouble wrapping my head around this.

5 Comments
2024/11/13
08:28 UTC

1

Is the green on earth like planet plants?

Because if they are doesn’t that mean that we’ve found life on other planets, and if not what is it?

6 Comments
2024/11/11
22:38 UTC

3

Can the atmo slow a thin light object enough to survive reentry?

If I threw my t-shirt from the ISS and waited until its orbit decayed, could the early air resistance possibly slow it down enough that it wouldn't burn up in the denser atmosphere below? I realize a Mach 40 wind is going to heat things up, but if that wind is initially 10^-6 Pa, might it slow the shirt way down before its destroyed? T-shirts are easier to slow down than a metal meteor or satellite. And if not my t-shirt, what about a feather, a pollen fluff, or a hollow block of aerogel?

5 Comments
2024/11/03
18:43 UTC

4

Do you lose speed in space?

If I was going 25 miles per hour in a no gravity vacuum (space), and if there was no other objects to pull me into, would I stay at 25mph for infinity?

8 Comments
2024/11/01
19:00 UTC

1

Did I see the SpaceX Falcon 9 rocket booster landing?

In the early morning of October 31st, between 3am-4am, I went outside to let the dog out and heard a noise like an airplane. I didn’t pay much attention to it until I realized it had more bass in its tone. It was slowly getting louder. I searched the sky and found a bright flickering light that seemingly was descending towards the horizon. As it went out of sight, the sound slowly disappeared. I went inside and found my phone to try and figure out what it was.

I found that its descent towards the horizon, on a compass, was roughly 75 degrees NE from my position in Greenville, South Carolina. A Falcon 9 rocket was launched from Florida on the Oct. 30.

I find it odd that I would be able to hear and see it, but was this a SpaceX Falcon 9 booster landing?

2 Comments
2024/11/01
06:08 UTC

3

Atlas rocket family tree?

The Atlas rocket has a long and winded family history. I was wondering if anyone has ever put together a "family tree" of the Atlas rocket. Google isn't being helpful...

1 Comment
2024/10/27
14:30 UTC

2

Starship/Superheavy max Q / throttling?

I seem to remember that Falcon 9 throttles a bit down around max Q in order to keep Q below about 25 kPa, without which it would max out just around 30 kPa. Does anyone know how much - or even if! - Superheavy throttles down around max Q, and what value of Q they want to stay below?

1 Comment
2024/10/26
09:21 UTC

0

Could you theoretically shoot a basketball from space and score in a net?

If an astronaut shot a basketball down to earth would the ball have a possibility of landing in a net or would the ball break up in the atmosphere on the way down?

7 Comments
2024/10/26
02:21 UTC

0

Seeing the past?

I have a theory about looking back in time. So we all know how the James Webb see millions of lights years into the past. Could we in theory tone it down a bit and point it at the earth to look back in time. This has no research behind it so someone smart explain why not.

15 Comments
2024/10/23
23:48 UTC

4

Could this possibly be a planet?

I used my phone and an 18x telescope thing for my camera, so my bad for the quality. I got a good picture of the moon, and a bright star next to it. However when it went out of focus, it enlarged it. I changed positions, wiped my camera but the line was still there. Could it maybe be Jupiter? (I rotated my phone too, so that's why the line isn't on the same side)

Pictures

2 Comments
2024/10/19
20:52 UTC

0

How is it that Venus has an Ozone with no hole and Runaway Greenhouse Effect to wild levels? While also having every element that we believe "causes" the hole here?

Or is it the hole was always there and we're just making it bigger.

I went down the rabbit hole and Examined quite a few planets/moons/asteroids' South pole, All of them with the Exception of Uranus, probably because it rotates on its side, have unexplained phenomena going on .

Mercury-Rather large Ringed Crater-like moon

Earth- Ozone Gone

Venus--Double Vortex

Jupiter--8 powerful storms

Saturn--Hexagon Storm-

Vespa(Asteroid)--Rather large Ringed Crater--Theres Actually 2 of them really close but the older is off centered from the pole

Our Moon---Rather large Ringed Crater-Similar to Mercury,and other moons--Our moon is also Dumping Sodium on us.

Mars-Ice caps both Poles- The Ice at its poles look eerily similar to Antartica in shape.

Pluto- Not sure But i think it's the Heart.

Titan--vortex

Neptune-- South Pole Much warmer than the rest of the planet. The false neg images Make the heat source look exactly like the Ringed craters mentioned above.

Enceladus and Europa --Have rather warm Southpoles that shoot Water Vapors out of them.

There's So many of the exact same Ringed Impact crater on moons, Asteroids and planets, then some of the bodies that don't have it have energy readings that mimic the same ringed Impact craters. the chances even in a billion trillion years of that all being a coincidence seems a bit far fetched.

It seems we are explaining too many events as random impacts, there seems to be a uniform phenomena throughout the solar system when it comes to the Poles.

2 Comments
2024/10/17
16:45 UTC

2

Is there any truth to this video about 2024 PT5

This TikTok creator is claiming he’s figured out that it’s actually 2km not 33ft in size and that it’s trajectory is not what’s being reported

https://www.tiktok.com/t/ZTF9gNpwc/

4 Comments
2024/10/17
15:10 UTC

1

black hole sucking in our galaxy

if there were a big black hole sucking in our galaxy, how long would it take to affect earth and would we even notice within our lifetime? sorry if it’s a stupid question i just randomly got curious and needed to ask. what if it was a black hole sucking in our solar system? how was that affect us?

20 Comments
2024/10/17
03:53 UTC

2

Planet 9/X Math

So Planet X mathematically makes sense. But where is that math? I believe there could very well be a ninth planet out there but I want to lay out all the evidence I can find on one table and look from there. I've gathered bits and pieces online but I want to see the actual math that was done.

Apart from models and theories, everything surrounding it in general media is just regurgitating from the news articles before it.

"Caltech researchers have found mathematical evidence suggesting there may be a "Planet X" deep in the solar system." Can I find that mathematical evidence or am I out of luck?

1 Comment
2024/10/14
00:59 UTC

2

Does the universe exist under us?

Edit: when I say underneath us, I mean under the planet it’s self😅

This seems like such a silly question but it’s literally keeping me up at night..

So spaceships go upwards and outwards to our infinite universe, satellites and what not go around us..

But is the stars and planets underneath us? If the universe is infinite I suppose so, but I can’t wrap my head around it.

10 Comments
2024/10/13
12:27 UTC

3

Do you think astronauts are always super excited about their job?

Or do they get too used to it and start to think “another long day of space work :(“

4 Comments
2024/10/09
18:46 UTC

3

Why are the centre of the galaxies always bright if every galaxy is supposed to have a black hole at the centre of it.

I think this might be a really stupid question. Every or almost every galaxy has a huge black hole in it’s centre . In photos or illustrations the centre of the galaxy is always very bright like a huge star is there e.g. Andromeda Galaxy. Shouldn’t it be a huge black spot if there is a black hole there? Help

6 Comments
2024/10/07
22:57 UTC

5

Where are the photos of 2024 PT5?

Rumors about a "second moon" in our sky and not a single photograph of this, although the article below states that it was captured on 9/29 by a team in South Africa.

https://www.earth.com/news/its-official-earth-now-has-two-moons-captured-asteroid-2024-pt5/

I can't find a single image of this that isn't computer-generated. What gives?

5 Comments
2024/10/04
06:09 UTC

3

Can someone better explain to me how earths gravitational field captured the PT5 2024 asteroid if asteroids normally move at a fast speed. I’m just confused

11 Comments
2024/10/03
22:21 UTC

2

General Relativity?

I’ve been trying to study general relativity and space time, and I kinda get the concept of it but I don’t fully understand it. Can someone possibly explain it in a way that could be a bit easier to understand?

7 Comments
2024/10/03
06:59 UTC

11

do boobs bounce in space?

think

12 Comments
2024/09/30
22:33 UTC

2

State of dead astronaut in capsule?

What would happen to the body of an astronaut who died in a space capsule/ship in outer space, with the capsule being locked from outside elements the entire time? If decades later the capsule were retrieved would the astronaut's body have decayed typical of deceased humans on Earth, or would his body look like he was still alive, like that of Tollund Man?

4 Comments
2024/09/30
04:20 UTC

2

The satellites around the Earth slow the Earth's Rotation?

I was watching the 2017 documentary The Farthest, about the Voyager mission, and one of the scientists said that when Voyager 1 was orbiting Jupiter it slowed Jupiter's rotation by 1/trillionth. Had never considered that before. Is it possible that we could one day have too many satellites orbiting Earth, that would slow the Earth's rotation to a dangerous level?

2 Comments
2024/09/29
11:40 UTC

0

Why was it assumed Voyager 1 and 2 wouldn't discover more planets after Neptune?

After Voyager left Neptune the cameras were shut off to conserve energy and the new mission became the "Interstellar Mission." But how did they know that there were no more planets to discover, not detectable from Earth? Were they using the Voyager instruments to try to detect other bodies past Neptune?

3 Comments
2024/09/29
11:29 UTC

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