/r/askastronomy

Photograph via snooOG

For your astronomy-related questions and content!

"We make our world significant by the courage of our questions and by the depth of our answers." - Carl Sagan

/r/askastronomy

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2

Does anybody here also feels terrified but fascinated to the concept of space?

I am constantly fearing the infinity and never-ending expansion of space. The unknown and what we’ve come to learn from it. I still happen to be attracted to it and can’t get enough from studying it. Maybe it’s my anxiety or OCD but it’s like I NEED to know everything about it space despite being terribly afraid of black holes and traumatised by it because I will think about them at least 474822837 times a day. The hunger to understand string theory, my extreme fascination for dark matter. The more I read about it, the more I want to stop but can’t do it. Does somebody else also feel like this?

4 Comments
2025/01/31
22:47 UTC

1

What is this galaxy cluster?

Inspired by a recent post about a faint distant galaxy I looked over some of my old broadband data of M45 and found UGC2839 at a distance of 300Mly.

My old data

Looking around the area on Sinbad I quickly discovered what appears to be a much more distant small galaxy cluster.

Any idea if it is described? Looks like a very interesting let's say "advanced" astrophotography target.

Sinbad unknown cluster

0 Comments
2025/01/31
18:19 UTC

1

What's about the T Coronae Borealis (T CrB) nova explosion update?

is there any update about the T Coronae Borealis (T CrB) nova explosion? As it was hyped last year

4 Comments
2025/01/31
17:16 UTC

4

Does saturn look bigger some days and smaller on other days?

I find myself thinking occasionally that saturn looks particularly bigger/brighter some days. Made me wonder if planets can do that- unlike stars- cuz they are closer some days/ or we see phases like the moon? Is that a thing? Can't seem to find any answer with a Google search..

4 Comments
2025/01/31
11:52 UTC

2

Shooting star?

So I’ve seen shooting stars before but just now, a huge white ball of light (almost as if someone shot a flare) appeared in the sky and then kinda fell back down. Just wondering if it was just abnormally big shooting star or what else it could be?

4 Comments
2025/01/31
04:12 UTC

0

I'm astronomically ignorant regarding astronomy. What in the world is this?

I was messing around with a new camera, getting a feel for settings w/ night photography and noticed this... green swirly thing... underneath Orion. It shows up in every photo I took of this section of the sky but this is the most clear image. I have not done anything to the image other than add the red circle of death.

I have no idea what to search, google did not show up with anything, though to be fair, I have no idea what to search for.

I also tried to find it in Sky Tonight and Skysafari with no luck.

Edit: I'm in Northern Colorado, USA if that helps

https://preview.redd.it/npmivwdm09ge1.jpg?width=8288&format=pjpg&auto=webp&s=f9a711eaf06983b483c45f5d4665b35988a05560

10 Comments
2025/01/31
03:26 UTC

3

How feasible is an analemmatic sundial with a stationary perpendicular gnomon?

In the city of Barbate, Spain, there is a plaza paved as a giant analemmatic sundial, with a lighthouse as the gnomon. I haven't found an explanation anywhere as to how this dial works and how it is read. Would a dial of this kind really be accurate? And if not, is there a better way that the face of the dial could be designed to show time more accurately?

0 Comments
2025/01/30
23:56 UTC

2

I know that the synodic period of Mercury is 116 days, but how long are each of the phases?

What is the length of time that it is viewable in the morning, "invisible" behind the sun, viewable in the evening, and "invisible in front of the sun?

1 Comment
2025/01/30
18:38 UTC

0

Do planets ever align in the summer like they are right now?

It feels like the best celestial events are in the bitter cold.

16 Comments
2025/01/29
23:15 UTC

7

Why don't we image proxima centauri B?

In the night sky proxima Centauri B is roughly just barely smaller in arcseconds compared to Sgr A, which we have imaged. Proxima Centauri C is even bigger than B is as well! So why don't we attempt to take the first image of an exoplanet?

4 Comments
2025/01/29
22:38 UTC

0

The Sun rises from West and sets in East.

The title is not clickbait. Isn't the sun supposed to rise from East and set in West? I'll link two videos I found where clearly the sun rises from the West and sets in East.

Nome (Alaska): https://youtu.be/AVf9IenF2jg?si=2UnKQG4WU0bkqYSl

Bristol (UK): https://youtu.be/Ys1w9A4DrO4?si=M_LG_Cy244CRzNqr

can someone explain?

11 Comments
2025/01/29
21:17 UTC

0

Hello

What's a good way to tell constellations apart

6 Comments
2025/01/29
17:51 UTC

0

Would we be able to observe a lunar body traveling towards us from thousands of light years away? Can we receive imagery data over vast distances in real time?

I’m no astronomer, so this may be a silly question. If so, I’ll happily delete it. Just curious.

When our observation tools see something hundreds or thousands of light years away, we’re observing that place as it was a looong time ago. But what would it look like if we tried to observe a lunar body traveling towards us from a distance like that?

Would there be an exponential decrease in “light lag” as the object gets closer?

Are there any mechanisms we know of that would allow us to receive data in real time over vast distances?

6 Comments
2025/01/29
10:09 UTC

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