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Energy output, as absolute brightness (magnitude) is taken at a standard distance of 10 parsecs.
Yazmin Sawayn
Wiki User
∙ 14y agoThere are two factors in the "visual magnitude" of a star, the number that we use to express its relative brightness in the sky. The first is the actual brightness or "absolute magnitude", and the second is distance.
After all, a car's headlight is WAY brighter than a candle flame - but a candle flame a foot away looks brighter than a headlight a mile away.
The brightest star in the sky is the Sun; it is only 93 million miles away, 8.2 light minutes from Earth. It has a "visual magnitude" of -26.7. The Sun is so bright that its glare can blind us, and we get sunburns in just a few minutes. It has an absolute magnitude of 4.6. (The lower the number, the brighter the star. A star with a magnitude of 1 is 10 times brighter than a star with a magnitude of 2.)
The second brightest star in the sky is Sirius, at 8.7 light YEARS away, with a visual magnitude of -1.5. Sirius is a bright dot in the black sky. It has an absolute magnitude of 1.4, which means that Sirius is actually over 1,000 times brighter than the Sun. But the Sun is close, and Sirius far away.
The CLOSEST star (other than the Sun) is Proxima Centauri, at a distance of 4.2 light years; HALF the distance to Sirius. Proxima Centauri is INVISIBLY DIM; you cannot see it without a telescope. Proxima Centauri is a red dwarf star, with a visual magnitude of 11.5 (7 is the dimmest star you can see with the naked eye) and an absolute magnitude of 15.5.
Wiki User
∙ 10y agoThere are 2 main factors: the size of the star and its surface temperature.
A larger size means a larger surface area to emit light.
A higher surface temperature increases the energy emitted.
Seen from Earth, the brightness of a star depends on how far away the star is as well as its actual luminosity.
Wiki User
∙ 13y ago- It's luminosity (Brightness)
- It's distance from the observer.
- The amount of "cover" - stellar debris in the way.
Anonymous
that it when it gets closer, it gets brighter
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What factor affects the luminosity of a star?
the size of a star
Are The most common type of stars are low luminosity stars?
Yes. Around 76% of the stars are low luminosity stars.
What is a sentence with luminosity?
The stars in the night sky shine with a remarkable luminosity.
How do you determine a stars luminosity?
To determine a star's luminosity is from size and temperature.
If a star is blue is its luminosity high or low?
Blue stars are very hot stars and so usually have high luminosity.
What factor affects the luminosity of a star?
the size of a star
Are The most common type of stars are low luminosity stars?
Yes. Around 76% of the stars are low luminosity stars.
What is a sentence with luminosity?
The stars in the night sky shine with a remarkable luminosity.
How do you determine a stars luminosity?
To determine a star's luminosity is from size and temperature.
If a star is blue is its luminosity high or low?
Blue stars are very hot stars and so usually have high luminosity.
Why are most visual binary stars of low luminosity?
If the binary stars were of too high luminosity it would be impossible to distinguish the two through vision alone. Therefore most visual binary stars are of low luminosity.
What process of losing their outer layer causes stars to lose?
luminosity or brightness
What does a stars luminosity measure?
Luminosity is the total amount of energy emitted by a star per second.
What is the stars intrinsic brightness called?
Luminosity.
Which of the following luminosity classes refers to stars on the main sequence?
The basic luminosity classes are: I for supergiants, III for giants, and V for main-sequence stars.
What describes the relationship between the luminosity of two stars that have the same radius?
The star that is hotter will have a higher luminosity.
Why are dwarf stars dim?
Dwarf stars are dim because they are small, so their luminosity (amount of emitted energy) is low compared to other stars, and low luminosity means more dimness.
