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Over 90% of the stars in the sky are main-sequence stars, primarily composed of hydrogen and helium. These stars, including our Sun, generate energy through nuclear fusion in their cores, converting hydrogen into helium. Main-sequence stars vary in size, temperature, and color, but they dominate the stellar population in the universe.
What else can I help you with?
When is the star canopus visible?
Canopus is one of the brightest stars in the sky and can be seen from latitudes between +37° and -90°. It is typically best viewed during the Southern Hemisphere's summer months (December to February) when it is high in the sky.
What percent is main sequence stars?
Main sequence stars make up about 90% of all stars in the universe. They are the most common type of star and are considered to be in a stable phase of their lifecycle.
What is a basic building block of galaxies?
I am not sure there is one. Galaxies contain stars, gas, dust, black holes and other dead stars, and - above all - dark matter. The dark matter typically makes up 80-90% of a galaxy's mass.
How do you calculate the range of declinations for which stars are circumpolar?
To calculate the range of declinations for which stars are circumpolar, you need to know the observer's latitude. Circumpolar stars are those that never set below the horizon. For a given latitude ( \phi ), the declination (( \delta )) of circumpolar stars ranges from ( +90^\circ - \phi ) to ( -90^\circ + \phi ). Thus, if you are at a latitude of, say, 40°N, circumpolar stars would have declinations between ( +50^\circ ) and ( -50^\circ ).
What is the formula for calculating whether a star is circumpolar viewed from a northerly latitude?
To determine if a star is circumpolar (never sets) when viewed from a northerly latitude, you can use the formula: 90° - latitude + declination >= 0. If the result is greater than or equal to zero, then the star is circumpolar from that latitude. The declination is the star's angular distance north or south of the celestial equator.
Which element makes up over 90 of the atoms in our galaxy?
Hydrogen is the element that makes up over 90% of the atoms in our galaxy. It is the most abundant element in the universe and plays a crucial role in the formation of stars and galaxies. In addition to hydrogen, helium is the second most abundant element, but its presence is significantly less than that of hydrogen. Together, these elements are fundamental to the structure and evolution of the cosmos.
What is the luminosity of the night sky. How much light do the stars produce relative to us compared to the sun?
The luminosity of stars varies quite a bit. Most stars (about 85-90% of them) emit less light than our Sun, while a few very massive stars emit, in extreme cases, over a million times as much light (or more precisely: total radiation) than our Sun.
Why are stars visible on one side of the sky in one month but on another side of the sky a few monthes later?
The Earth travels in its orbit around the Sun, and so our perspective on the night sky changes a little (about one degree per day) as time goes on. And remember that because the Sun is so bright (well, not so bright, but so CLOSE) and because our atmosphere scatters the sunlight around the sky, we generally can't see stars in the daytime. In three months, for example, the Earth will have moved 90 degrees around its orbit - which means that the stars will appear to be 90 degrees away from where they seemed to to be.
What religion makes up over 90 percent of the population of the middle east?
90% of middle easterners are Muslim.
When is the star canopus visible?
Canopus is one of the brightest stars in the sky and can be seen from latitudes between +37° and -90°. It is typically best viewed during the Southern Hemisphere's summer months (December to February) when it is high in the sky.
What makes an obtuse angle?
An angle must be over 90 degrees to be obtuse.
What 90's song has the phrase until the stars fall down on me?
I think you mean Truly Madly Deeply by Savage Garden, and its 'until the sky falls down on me'.
About 90 percent of the stars in space are stars?
About 90 percent of the stars in space are main sequence stars. These stars, like our sun, are in the middle of their life cycle, where they are fusing hydrogen into helium in their cores. Other types of stars, like white dwarfs, neutron stars, and black holes, make up the remaining 10 percent.
90 percent of the stars are what stars?
90% of the stars in the universe are classified as main sequence stars, which includes stars like our sun. These stars are in the stable phase of their life cycle, converting hydrogen into helium through nuclear fusion in their cores.
What percent of the stars in space are main sequence stars?
Approximately 90%.
Where are 90 percent of stars on hr diagram?
main-sequence stars
Are more stars circumpolar at the North Pole or in the US?
The simple answer: "at the North Pole". A more detailed answer: ALL stars are "circumpolar" in the sense that they seem to rotate around points above the Earth's poles (called the "celestial poles"), as the Earth turns. But we use that word to mean stars that are close enough to the poles of the sky so that they don't rise or set at the observer's latitude. By that definition, the stars that are 'circumpolar' from any location are those that have "declinations" not less than 90 degrees minus your latitude. Declination is a measure of how far a star is from being above the Earth's equator. Polaris, the "pole star", has a declination of nearly 90 degrees, and is almost exactly above the Earth's North Pole. The greatest possible geographic latitude is 90 degrees, at either pole, so that's where the greatest possible amount of sky is 'circumpolar'. At the north pole, half of the entire sky is visible at any time the sky is clear, during the six months of "night". No star ever rises, and none ever sets. Each one just goes around and around the sky, parallel to the horizon and never moving higher or lower in the sky. And you never see anything that's in the OTHER half of the sky. At the other extreme ... for an observer standing on the Equator, nothing in the sky is circumpolar, and you can see every celestial object sooner or later.
