The simple answer is that — in accordance with both ancient astrological tradition and modern astronomy — the Sun technically has no constellation. But if you were to change locations and travel to a new star system, you would then be able to view the Sun as we do other distant collection of stars.
Unfortunately, depending on where you are, the answer would change. First, let us consider the astrological answer to this question. Unless you were born prior to the Scientific Revolution — during which time Nicolaus Copernicus proposed the heliocentric model of the Solar System — you know that the Earth revolves around the Sun.
During the year, the Sun passes through each of the constellations of the Zodiac. Your astrological sign is based on this.
However, astrology is an obsolete and entirely unscientific practice. And if someone were to ask which constellation the Sun is in, surely they are seeking an answer that was astronomical and not astrological in nature.
For that, we must consider what the constellations are in scientific terms. By definition, these are collections of stars that, when viewed from Earth, appear in the same general area as each other night after night. In reality, they are actually located in very different locations, and can sometimes be up to thousands of light-years away from each other.
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When a star reaches a mass of more than 1. The result is a supernova. Gravity causes the core to collapse, making the core temperature rise to nearly 18 billion degrees F 10 billion degrees C , breaking the iron down into neutrons and neutrinos. In about one second, the core shrinks to about six miles 10 km wide and rebounds just like a rubber ball that has been squeezed, sending a shock wave through the star that causes fusion to occur in the outlying layers.
The star then explodes in a so-called Type II supernova. If the remaining stellar core was less than roughly three solar masses large, it becomes a neutron star made up nearly entirely of neutrons, and rotating neutron stars that beam out detectable radio pulses are known as pulsars. If the stellar core was larger than about three solar masses, no known force can support it against its own gravitational pull, and it collapses to form a black hole. A low-mass star uses hydrogen fuel so sluggishly that they can shine as main-sequence stars for billion to 1 trillion years — since the universe is only about Still, astronomers calculate these stars, known as red dwarfs , will never fuse anything but hydrogen, which means they will never become red giants.
Instead, they should eventually just cool to become white dwarfs and then black dwarves. Although our solar system only has one star, most stars like our sun are not solitary, but are binaries where two stars orbit each other, or multiples involving even more stars. In fact, just one-third of stars like our sun are single, while two-thirds are multiples — for instance, the closest neighbor to our solar system, Proxima Centauri , is part of a multiple system that also includes Alpha Centauri A and Alpha Centauri B.
Still, class G stars like our sun only make up some 7 percent of all stars we see — when it comes to systems in general, about 30 percent in our galaxy are multiple , while the rest are single, according to Charles J.
Lada of the Harvard-Smithsonian Center for Astrophysics. Binary stars develop when two protostars form near each other. One member of this pair can influence its companion if they are close enough together, stripping away matter in a process called mass transfer. If one of the members is a giant star that leaves behind a neutron star or a black hole, an X-ray binary can form, where matter pulled from the stellar remnant's companion can get extremely hot — more than 1 million F , C and emit X-rays.
If a binary includes a white dwarf, gas pulled from a companion onto the white dwarf's surface can fuse violently in a flash called a nova.
At times, enough gas builds up for the dwarf to collapse, leading its carbon to fuse nearly instantly and the dwarf to explode in a Type I supernova, which can outshine a galaxy for a few months.
Astronomers describe star brightness in terms of magnitude and luminosity. The magnitude of a star is based on a scale more than 2, years old, devised by Greek astronomer Hipparchus around BC.
He numbered groups of stars based on their brightness as seen from Earth — the brightest ones were called first magnitude stars, the next brightest were second magnitude, and so on up to sixth magnitude, the faintest visible ones. Nowadays astronomers refer to a star's brightness as viewed from Earth as its apparent magnitude, but since the distance between Earth and the star can affect the light one sees from it, they now also describe the actual brightness of a star using the term absolute magnitude, which is defined by what its apparent magnitude would be if it were 10 parsecs or The magnitude scale now runs to more than six and less than one, even descending into negative numbers — the brightest star in the night sky is Sirius , with an apparent magnitude of Luminosity is the power of a star — the rate at which it emits energy.
Although power is generally measured in watts — for instance, the sun's luminosity is trillion trillion watts— the luminosity of a star is usually measured in terms of the luminosity of the sun. For example, Alpha Centauri A is about 1. To figure out luminosity from absolute magnitude, one must calculate that a difference of five on the absolute magnitude scale is equivalent to a factor of on the luminosity scale — for instance, a star with an absolute magnitude of 1 is times as luminous as a star with an absolute magnitude of 6.
Stars come in a range of colors, from reddish to yellowish to blue. The color of a star depends on surface temperature. A star might appear to have a single color, but actually emits a broad spectrum of colors, potentially including everything from radio waves and infrared rays to ultraviolet beams and gamma rays. Different elements or compounds absorb and emit different colors or wavelengths of light, and by studying a star's spectrum, one can divine what its composition might be.
Astronomers measure star temperatures in a unit known as the kelvin , with a temperature of zero K "absolute zero" equaling minus A dark red star has a surface temperature of about 2, K 2, C and 4, F ; a bright red star, about 3, K 3, C and 5, F ; the sun and other yellow stars, about 5, K 5, C and 9, F ; a blue star, about 10, K 9, C and 17, F to 50, K 49, C and 89, F.
The surface temperature of a star depends in part on its mass and affects its brightness and color. Specifically, the luminosity of a star is proportional to temperature to the fourth power. For instance, if two stars are the same size but one is twice as hot as the other in kelvin, the former would be 16 times as luminous as the latter.
Astronomers generally measure the size of stars in terms of the radius of our sun. For instance, Alpha Centauri A has a radius of 1. Stars range in size from neutron stars, which can be only 12 miles 20 kilometers wide, to supergiants roughly 1, times the diameter of the sun.
The size of a star affects its brightness. Specifically, luminosity is proportional to radius squared. For instance, if two stars had the same temperature, if one star was twice as wide as the other one, the former would be four times as bright as the latter.
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