Questions tagged [night-sky]

Questions regarding the visible night sky during nighttime from Earth.

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22
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2answers
4k views

What exactly is the "paradox" in Olber's Paradox?

To the extent of my understanding, Olber’s paradox states that if the universe was static and homogeneous, we should see a star at every point in the night sky and therefore the night sky should be ...
19
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2answers
5k views

Are the stars distributed in uniform distribution, on the celestial dome, with respect to brightness?

Has there ever been a statistical analysis of the distribution of stars in the sky (on the surface of the celestial dome), by brightness? I want to know if they are uniformly distributed. For example, ...
17
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1answer
1k views

How much clearer are stars in earths orbit?

As a child I remember my parents taking camping in California, and upon stepping out of the car I was awestruck at how thick the Milky Way galaxy was and at the number of stars everywhere. I've always ...
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2answers
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Why don't we see "the milky way" in both directions?

We're (basically) in the middle of an arm of our galaxy. That is to say, we're sitting in the middle of a dense disc of stars. It would seem to me that. You should see: the thick line of the milky way ...
11
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2answers
2k views

Will Starlink deface the night sky?

There is some discussion (and there are some questions on this site) about the impact of Starlink on observational astronomy. I am not an astronomer, but I am amazed by the beauty an immensity of the ...
11
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3answers
577 views

Perceiving movement of stars

Are there any stars visible to the naked eye whose position, over a normal human lifetime, can be seen to have changed (relative to other stars in the vicinity)?
10
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1answer
365 views

What would our night sky look like if the solar system was 100 light years from the centre of the Milky Way

When we look at photo's of the centre of the Milky Way, it looks extremely bright due to the concentraion of star systems... If our solar system was only 100 light years from the centre of the Galaxy,...
9
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1answer
508 views

What's the white glow around this star?

A few days ago, I took a photo of the night sky in the mountains of Georgia with my DSLR. There, I noticed that one single star (in the center of the part of the photo that I added below) looks very ...
9
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2answers
328 views

In what parts of the world is it impossible to view the night sky due to light pollution?

Growing up far from any city, I have always been able to view the full night sky. It was just the way how things were. Of course, I knew that light pollution is a thing, and that the sky is a lot less ...
9
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1answer
2k views

How does the Moon move in the "night" sky as seen from the poles?

A photo in the NYTimes article Ice Surveys and Neckties at Dinner: Here’s Life at an Arctic Outpost has got me thinking. During the winter months at either the north or south pole, when it is ...
8
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4answers
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What is this rapidly twinkling red, blue, and white star I saw?

Last night, I was on my balcony at 1AM (PST) and I looked up and saw two stars near the horizon (I'd guess ~30 degrees above the horizon), and they were "twinkling" about twice as fast as other stars ...
8
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2answers
380 views

How will planets behave in the night sky as seen by Mars colonists?

Certainly among the first colonists on Mars there will be a few people interested in Astronomy enough to enjoy the night sky. For them, familliar Mars will be missing and there will be a new, ...
7
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2answers
467 views

My local night sky is so bright that I can only see the Moon, so would a low-cost telescope be any use?

Light pollution is so bad near our home that we can't see anything other the Moon in the night sky. For instance there is a street light on all night right in our lane and there are many other housing ...
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4answers
2k views

Is there an example of a star that is already dead, but can still be seen on Earth?

While looking up at the stars I wondered, what are the odds that some of them are already dead. I did some research and found a very interesting article here. It states that the odds are rather small, ...
5
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2answers
1k views

Is there a webpage that shows the night sky but can filter out dim stars?

This webpage is very good for viewing the night sky and learning the names of the stars Timeanddate - Astronomy However, it shows too many stars. Because I live in the city, I can only see about 50 ...
5
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1answer
473 views

What would the night sky look like if the interstellar medium didn't exist to absorb or block light?

I was curious about how much brighter it would be and how much further we could see.
5
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2answers
145 views

App that shows what's passing in sky?

I'm not an astronomer but I enjoy looking up at the sky. So tonight I saw something moving in the sky. It looked like a star, and it was definitely not a plane (I checked in flightradar). Is there ...
5
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1answer
481 views

Mars night sky -- Phobos and Deimos?

I'm having a debate about how bright Martian nights would be, in terms of both the sky itself and ground illumination. This answer seems to indicate that the stars would be only dimly visible, and ...
5
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1answer
129 views

Naked-eye limiting magnitude: mismatch between Wikipedia, online converter and Shaefer's formula

I'm trying to make sense of the difference between the reference Sky Quality Meter (SQM) readings given in the Wikipedia article on Bortle scale, online converters like [1] that are based on Shaefer's ...
4
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2answers
2k views

How can we know if a star which is visible in our night sky goes supernova?

Let's say there is a star about 3000 light-years away from earth visible in our night sky. If this star were to go supernova tomorrow(not relative to earth's night sky), we would know about it 3000 ...
4
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3answers
306 views

Did the night sky ever change in recorded history?

I wonder whether there has ever been a major change of the firmament in recorded history, like changes in the positions of stars, changes in constellations, or stars disappearing after going supernova....
4
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2answers
1k views

Why the Milky Way appears to be arching across the sky?

The Milky Way galaxy is disc-shaped and earth is in its plane: (source) In the following image the milky way appears to be arcing across the sky: (source) This looks like an out of plane view of ...
4
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1answer
690 views

What did the night sky look like 100,000 years ago?

Question in the title. Would any constellations be identifiable?
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2answers
2k views

Why do I see rainbows around the moon?

Regularly, I see rainbows around the moon. Here is approximately what I see: Right at the edge of the moon, I see a bright blue ring of light. Further out, I see an inner rainbow. This is not as ...
4
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1answer
180 views

What inaccuracies are in this Stellarium depiction of the sky?

I found this depiction on Stellarium of the sky as seen from near the Apollo 12 landing site on January 11, 2131. The earth is the black circle in the arm of the Milky Way. Here is a similar view ...
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0answers
189 views

What would go into the design of a simple sky quality meter, used to measure night sky brightness?

@MCG's answer mentions several methods to classify night sky quality or brightness, and goes on to say: Additionally, you could always purchase a SQM (Sky quality meter) which is a small, portable ...
3
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2answers
867 views

From our world's perspective, does the full moon look larger in one city than it does in another?

When I was a very little girl, my dad talked about the HUGE full moon he saw while in the navy. He made the comment during a full moon we were having in Western NYS. He said, this (harvest) moon is ...
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3answers
1k views

Star map - finding stars

Assume you are given a star map that doesn't have the name of the stars on it. You know the latitude, longitude of the observer and the local time (year, month, day, local time). How could I proceed ...
3
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3answers
157 views

Density of stars on celestial sphere

The pattern of stars on the surface of the celestial sphere seems perceptually to have an universally looking structure. If you pick a region of the sky at random, for instance by using the (excellent)...
3
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1answer
189 views

Is the dot on the photo - Mars?

The below photos were taken yesterday (August 4, 2018) at about 10 p.m. from the plane over the Black Sea. We were seeing the light dot on the left for at least 10-20 minutes. It looked like a bright ...
3
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1answer
558 views

Brightest star visible from Italy and Argentina

A friend of mine tends to ask crazy question about everything. Today he ask me what is the brightest star that is visible on both the hemisphere and in particular from Italy and Argentina. I tried to ...
3
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1answer
248 views

How come the northern and southern lights are the same?

Not an expert, hence the question. To my knowledge the magnetic field of the earth travels south to north. Wouldn't there be a bias on whether the charged particles causing the auroras are negatively ...
3
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1answer
506 views

Stars in multiple constellations

Are there examples of single stars that are a part of multiple constellations? What about stars that are part of one Western constellation and one non-Western? Thanks in advance!
3
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1answer
132 views

Sky in the very far future / past

Motivated by this question about a stranded submarine in the Jurassic I would like to know: Is there anything remotely left of our current skyline if we go back or forward millions of years so that ...
3
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2answers
93 views

Are there any bright non-stellar objects which make up asterisms?

Hopefully the title is very self-explanatory. I was wondering if there were any non-stellar objects, such as bright galaxies, which when looking with the naked eye were mistaken for stars in the time ...
3
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1answer
31 views

Is sky-glow affected by height?

I'm an architecture student and my graduation project will consist of building a research center for outer space, my question is whether or not height would affect sky-glow or not ? Thanks in advance, ...
3
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1answer
74 views

Where should I be looking to see Neowise in southern Sweden?

I'm in the south of Sweden and just spent over an hour trying to find Neowise, but didn't see it. I live in a rural area, there are no lights nearby and there is a small hill with clear visibility ...
3
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1answer
328 views

Is night sky getting brighter day by day?

Night sky is dark because light from distant stars has yet not reached our earth. Light emitted by stars formed after the instant of creation i.e. 13.7 billion light years ago is on the way to reach ...
3
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2answers
185 views

Which kinds of astronomical observations most need to avoid the Moon being up?

This comment to Did nobody in the Astronomy community think 12,000 new satellites in LEO might be a problem? links to Phys.org's New ESO study evaluates impact of satellite constellations on ...
3
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1answer
47 views

Star Map Vs Star Catalogue vs Planetarium Software

What is the difference between a star map, star catalogue and the sky provided by planetarium software? I have read the wiki but was having a hard time understanding how the data, accuracy and detail ...
3
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1answer
36 views

Brightness, altitude & azimuth for satellites?

I'm using the heavens-above website to identify a satellite I've seen several nights this week. The question is related to how I can search the satellites table with the information I can provide. ...
3
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1answer
87 views

Why doesn't the night sky keep on getting brighter and brighter every day? [duplicate]

I think this should happen because of the below logic. Consider Day 0 of planet earth. There is no light coming from any surrounding star that has reached our planet and hence its pitch dark. On Day ...
3
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0answers
72 views

Creating planispheres from the perspective of nearby objects

I'm attempting to create a set of [reasonably] astronomically accurate planispheres from the perspective of observers positioned at the north or south poles of various nearby celestial objects. So ...
3
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0answers
58 views

Is there a Free repository of pictures taken everyday of the night sky?

I'd like to know if there's a repository out there of pictures taken everyday of the night sky. Not looking forward to anything fancy. Maybe a group of people out there have set up something out of ...
2
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2answers
985 views

How much light would be reflected from Jupiter to Europa (in Europas night)?

Suppose Europa is found habitable and humans start living on it. Europa is close to Jupiter and during the night Jupiter would be reflecting light to Europa, just like our full moon reflects light to ...
2
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3answers
183 views

I'd like to photograph NEOWISE from Los Angeles, what is the optimal time?

I live in Los Angeles and have a camera adapter for my telescope -- nothing fancy just an Astromaster 114. What is the optimal time, in terms of dark sky and bright comet, to take a photo of Comet ...
2
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2answers
1k views

Why can I see the Andromeda Galaxy despite Milky Way's rotation?

Okay ... so, I woke up from a dream last night wherein I was (apparently) attempting to devise a time-keeping system for interstellar travel (similar to the stardate system used in Star Trek). In the ...
2
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1answer
171 views

Why does in-the-sky.org say that Mercury is not visible from Taipei these days?

I know that viewing Mercury is a challenge, but I'm fairly close to the equator and Mercury was at greatest elongation just a week ago. In-the-sky.org says: All around the world, Mercury is visible ...
2
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2answers
155 views

Does the Sun and Moon basically appear to "move on the sky" identically regardless of location and date?

For a long time, I've been trying to use Stellarium (simulation) and many visualizations and animations in order to get a good idea of how the Sun and Moon move across the sky, as seen by a human from ...
2
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1answer
73 views

How do I find out when a constellation reached its zenith?

I found this website to look at the sky at the specific time and location: http://www.fourmilab.ch/cgi-bin/Yoursky - you can insert latitude and longitude and time to see how the skies looked at any ...