# Tag Info

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

Naked eye stars are not distributed uniformly in the sky. That is because the median naked eye star is at a distance of 440 light years, and this is far enough away that some of the details of ...
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### Why don't we see "the milky way" in both directions?

I'll turn my comment into a full answer. To put it simply, we actually do see the Milky Way all around us, even in the diametrically opposite direction from the galactic core. You can see this in the ...
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Olber's Paradox was created at a time before the idea of a finite universe was accepted. (It was thought of in the 1600's). In order to resolve Olber's Paradox, you have to introduce the idea that ...
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### What could be an explanation for a satellite-like moving light in the night sky that dims over time

From your description, this was most likely a Satellite Flare. This is the Sun reflecting off a highly reflective part of the satellite. The most famous type was the flares from the Iridium ...
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### How much clearer are stars in earths orbit?

It varies. The best astronomical sites have a visual band extinction of 0.1 mag, which means that only $\sim 10$ per cent of light is absorbed/scattered in the atmosphere. In dusty, smoggy or ...
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### Why does the Milky Way appear to form an arch shape across the sky?

The Earth is a sphere (or is nearly a sphere). So to make a map of the whole Earth you would need to project it onto a flat surface. When you do this you create distortions. For example, on many maps, ...
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### How can we know if a star which is visible in our night sky goes supernova?

It is not possible to know. The speed of light is the speed of information. The information "the star has exploded" cannot travel faster than the speed of light, so there is no way to know ...
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### What is this, red, blue, white twinkling, star?

The star is most likely Vega. It doesn't actually twinkle, the technical term for this is "scintillation", and is purely an atmospheric effect. The general idea is that stars are so far away,...
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### What's the white glow around this star?

Astrometry.net has identified your star field as being part of the Andromeda constellation. The diffuse object in the centre of your image is the Andromeda Galaxy (Messier 31). The bright star to the ...
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### How am I supposed to locate the planets Uranus and Neptune with a 70 mm f/5.7 refractor?

Right now you won't. Both are on the "wrong" side of the sun and so not easily observable from Earth. At the moment (early 2020s) they are in the constellation of Aries and Pices which are ...
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### Will Starlink deface the night sky?

Satellites just add moving lights to the sky, they do not obscure stars. However, some may find that disrupting their view of what a sky should look like. The visual magnitude of starlink satellites ...
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### Is there a webpage that shows the night sky but can filter out dim stars?

I think your requirements can be met by Stellarium. It is a freely available open-source planetarium software available for PC, and can be used offline. There is also a web version, which you can try ...

### What could be an explanation for a satellite-like moving light in the night sky that dims over time

It very likely IS a satellite which is moving from the sunlit part into the shadow of the earth, dimming more and more as it crosses from the day side through twilight (partial earth shadow) to night.
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### Is there an example of a star that is already dead, but can still be seen on Earth?

There is an accepted answer already, but there is a couple known cases of a star we know has gone supernova, and yet we can still see it. This source describes one such unique circumstance. The star ...
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### Perceiving movement of stars

To answer this, I interrogated the revised Hipparcos catalogue produced by van Leeuwen (2007), accessed at the CDS, Strasbourg. There are 4559 stars in the catalogue with a Hipparcos magnitude $<6$...
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### How does the Moon move in the "night" sky as seen from the poles?

The moon is quite interesting as you get near the poles. It still moves round due to the Earth's rotation once a day, but it also orbits with a period of a month so what you get is two weeks of moon ...
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### Are the stars distributed in uniform distribution, on the celestial dome, with respect to brightness?

Alright I finally finished this program so I could take a look at each tier individually and see for myself. First of all, the projection type does indeed matter, so I will explain it here. It needs ...
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### Will Starlink deface the night sky?

A nightmare for star hopping I can only speak as an amateur astronomer with a 10-inch Dobsonian. My telescope has no GOTO or tracking, so if I want to find something interesting in the sky, I have to ...
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### How can we see Venus at night?

Before we begin: how far a planet is seen from the Sun is called elongation, and it's measured in degrees. 0° elongation means it's right on top of the Sun (or behind); 180° elongation means it's ...
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### What is this rapidly twinkling red, blue, and white star I saw?

It's most probably Sirius. At this time of year (at 1 am local time) it's low in the sky in the East, so there is a lot of atmosphere in the way, and as Sirius is a bright bluish star, it will show ...
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### How bright would the night sky be in the galactic center?

Interesting question. Assuming the figure of 10 million stars per cubic parsec is correct, there's still one missing piece of information to try getting a estimate: The size of this region with a very ...
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### How much light would be reflected from Jupiter to Europa (in Europas night)?

It's a pretty straight forward calculation of 3 factors. Distance from the sun, apparent size and albedo. I'm going to compare Jupiter to our full moon, since we're all familiar with that. ...
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The question has been addressed, but for completeness I should like to remark that the most thorough and readily understandable discussion of Olber's Paradox is that of E. Harrison in his book ...

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

Most high-redshift galaxies — i.e. the very distant ones, billions of light years away — are detected due to the UV light that comes primarily from very hot stars (in particular, copious amounts of ...
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### What would our night sky look like if the solar system was 100 light years from the centre of the Milky Way

I have tried to collate some info from various other answers. Density of stars where we are: About 0.15 per cubic parsec Density of stars "at the middle of the galaxy". Unfortunately I don'...
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### What would the night sky look like if the interstellar medium didn't exist to absorb or block light?

The main effect would be that the Milky Way would become much more prominent and asymmetric. At the moment, our view into the Galactic plane is limited to around 1000-3000 parsecs by dust. If you ...
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### Is there an example of a star that is already dead, but can still be seen on Earth?

You are, I think, asking two very similar but linked questions: Are there stars - in our galaxy, as stars in other galaxies are not individually visible - that are 'dead' but still alight to us. The ...
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### What is this rapidly twinkling red, blue, and white star I saw?

As you have already identified the objects you were seeing, I'll explain the effect you were seeing. In that situation there are three things to consider: atmospheric chromatic dispersion, seeing and ...
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### Throughout the year, are all parts of the night sky visible from any given point on Earth?

At any one time, only half the sky can be visible, and half is below the horizon. At the poles the sky appears to rotate about the zenith, and so no new parts of the sky ever become visible. At the ...
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