is the brightest star in the sky the one which is closest to us ?

Question

or is it the farthest away but the brightest ?or is it the smallest and closest ? or biggest but closest ? or the farthest away ? ....hmmmmmmm my universe is perplexing ...

Answer 1

Apart from the Sun, no.

When a star is proceeding thought its 'normal' adulthood, fusing hydrogen into helium in its core, we say it is a 'main sequence star'

The amout of light that a 'main sequence stars' puts out (Luminosity) is directly linked to its mass. The more massive ths star, the more luminosity (and the shorter the life on the main sequence).

Stellar formation theories tell us that it is (statistically) much easier to form small stars than big ones (e.g., a given large collapsing cloud is more likely to form many smaller stars than one huge star).

In addition, smaller stars stick around much longer.

Therefore, during our very brief history (astronomically speaking), we are more likely to be surrounded by faint small stars than by huge brilliant ones.

However, faint stars cannot be seen very far. Our own Sun would become invisible to us if we move off by a mere 50 light-years.

Most stars that we see in the sky are hundreds and thousands of light years away. Therefore, we only see the very bright (and far) stars. We do not see the faint close ones (unless we use a telescope, of course).

As far as the universe is concerned, remember this rule:

it is even weirder than you think.

Answer 2

Other people have given you some really good answers, but I'll just add some more info for perspective.

Venus is not a star, but after the sun and moon, it is the brightest thing in the sky most of the time it is visible. The sun is a star, but I know you were not asking about that. It's a dippy little yellow dwarf which doesn't even deserve a bathroom key on the cosmic scale.

Although Proxima Centauri, (not visible to the naked eye), is technically the closest star to our solar system, it is just a minor star orbiting the very visible Alpha Centauri. Both are considered 4.3 light years from the sol sys. Alpha Cen. is in the southern hemisphere and is the 3rd brightest star, as they appear to the naked eye.

Sirius is the brightest, by apparent magnitude, (as it appears to us.) It is 8.6 light years away.

But as far as actual brightness is concerned, (absolute magnitude), Sirius is a wimp compared to some of the bruisers we can see, which are much farther away. Two of them are in Orion. One is Rigel, a blue-white, very hot star, and really the boss star within 1000 light years from us. Betelgeuse is a red giant, much larger than Rigel, but not as bright. It is a rather cool star and not nearly as dense or hot as Rigel. At around 500 light years, it's a bit more than half the distance to Rigel. Rigel is the 7th brightest by apparent magnitude, and Betelgeuse is 9th. Deneb, in Cygnus, is much like Rigel, only 1400 light years away.

The brightest stars known are not visible to the naked eye because they are so far away or because of obscuring gas and dust, with the exception of eta Carinae a red hypergiant. It is getting brighter and is barely visible to the naked eye at about 8000 light years distant. It is believed to be about 4 million times brighter than the sun and is very possibly the brightest star known. It is also a double star. Stars like Rigel, Betelgeuse, and Deneb are on the order of 80,000 to 100,000 times brighter, if they were sitting side by side.

Some stars nova, or flare up for brief periods. Some become supernovae, which far outshine any normal star before dwindling down to invisible pulsars or black holes. When eta Carinae superenovas, it will light up the whole southern night sky. In astronomical terms, that cataclysm is imminent, perhaps as soon as a million years from now! Don't touch that dial.

Answer 3

Most of the bright stars we see in the night sky are actually quite far away. They are bright because they are enourmus. One of the nearest stars, Rigel Kentaurus of Alpha Centauri, is only the 4th brightest star. Sirius A is the brightest and is twice as far. Second brightest is Canopus which is 313 lightyears away and has to be 14000 times as luminous as the sun to pull that off! The reason it is is because it is also alot bigger than the sun (it is a supergiant 65 times as big as the sun) and stellar luminosity is proportional to the stars size.

Answer 4

Proxima Centauri is the closest star (after the sun) but has a mass only 1/8th of our sun and is not a very bright star.

venus is not a star but often touted as the Brightest object in the sky (after moon and sun)

the brightest star is Sirius, which lies about twice the distance from earth as Proxima Centauri

Answer 5

No.

Sirius is close, but Alpha Centauri is closer, though not as bright.

Many of the bright stars in the sky are close by, like Procyon, Vega and Altair. But other bright stars are a long way away, like Deneb and Canopus.

Astronomers sort this out with the idea of absolute magnitude, how bright a star would be if it was 32 light years (10 parsecs) away. If it was 32 light years away, our Sun would be fairly dim, and so would Alpha Centauri. But Deneb and Canopus would both be brighter than Venus.

Answer 6

Brightness of a star depends on 2 things:
1. how close it is
2. how bright it really is (called intrinsic brightness or absolute magnitude).

So a really big bright star really far away would look dim compared to a smaller star really close.

Try this. Get a small dim flashlight, and a large bright flashlight (and 2 friends to help). Now you need a dark area (like a field or parking lot at night).
Have both friends stand 20 meters away and have them both shine their lights at you. The small one is dimmer than the big one.
Now have the friend with the small flashlight move to only 10 meters away, and the one with the large flashlight move to 100 meters away. Now the small one is brighter.

Scientists measure 2 brighness values of a star:
1. Its apparent magnitude (how bright it looks to us on Earth)
2. Absolute magnitude - how bright it would appear a 10 parsecs or 32.6 light years away (this is like the first experiment where both friends were 20 meters away and the lights were different).

As for stargazing, the apparent magnitude is what is listed on star charts, since that's what matters to people looking at the stars. How bright it really is (absolute magnitude) doesn't matter so much when you're just looking at the night sky.

Answer 7

No, Sirius is not the closest star to us, but instead it and it's white dwarf companion are the fifth closest star system to us after Alpha Centauri, Barnard's Star, Wolf 359 and Lalande 21185. All of them except Alpha Centauri A and B, as well as Sirius are red dwarfs much smaller, fainter, denser and cooler than the Sun. It's at a distance of 8.6 light years where as Proxima Centauri, the distant companion to Alpha Centauri, is a mere 4.2 light years away.

Answer 8

No.

Closest star = Proxima Centauri in the centaurus constellation. About 4.2 light years away. It is a red dwarf and so is not bright enough to be seen with the naked eye.

Venus is a planet but is the brightest thing in our sky other than the Sun and Moon.

Brightest star = Sirius, with is approx 8.7 light years away. It is quite a bit larger than our sun, and many many times brighter.

Answer 9

The birghtest "star" in the NIGHT sky is a planet.. Venus.

Brightest actual star in the night sky would be Sirus.
At a mere 8.5 light-years away, Sirius seems so bright in part because it is fifth closest star to the Earth and it is 23 times more luminous and about twice the mass and diameter of the Sun.

Answer 10

No. There are two factors influencing apparent brightness: distance, and actual brightness. Both of these factors vary over a huge range. So the apparent brightest star may not be the closest -- it may be actually brighter than ones that are closer.