|Is the sun the hottest star in the Universe? |
|Question Date: 2013-02-19|
Good question! Our sun is very, very hot, but
it is not the hottest star in the universe. The
sun, like all other stars, has different stages
in its “life”. The physical conditions of the
star (including temperature) and its nuclear
reactions are different in the different stages.
Right now the sun is in the main sequence stage,
during which it is about 10 million degrees
Celsius (Dickin, 2005). Later in its life, a
star may turn into a red giant. A red giant is
not very hot at its surface, but its core may
reach 1 billion degrees Celsius (that’s 100
times hotter than the sun) (Dickin, 2005). The
sun has not reached its red giant stage yet (and
probably won’t for another several billion
years), but many other stars in the universe are
hot red giants.
Not all stars in the universe are the same
size. Some stars are much more massive than the
sun. The stars which are several times bigger
than our sun may turn into supernovae.
Supernovae are stars that contract so much that
they eventually explode. They may reach
temperatures of 3 billion degrees Celsius
(that’s 300 times hotter than the sun) right
before they explode (Dickin, 2005).
Dickin, A.P. (2005). Radiogenic Isotope Geology:
2nd edition. New York: Cambridge University
NO. The hottest stars have surface
temperatures of 50,000 Kelvin degrees. The Sun
surface is only 5800 Kelvin degrees, which means
that there are hotter starts than the Sun.
The sun is an "averagely hot" star in the
universe. There are many stars that are hotter
than the sun -- for instance, stars that burn
blue are hotter than our sun!
No; in fact, the Sun is a fairly faint, cool
star. We don't know exactly what the hottest
star in the universe is, but a class of stars
called Wolf-Reyet stars (named after the guys
who discovered/described them) are currently the
hottest/brightest stars known.
No, the Sun is not the hottest star; there
are many stars much hotter
than the Sun! You can tell the approximate
temperature of a star by
looking at its color. The coolest stars are red,
then orange, then
yellow (like our Sun). Even hotter stars are
white and then the
hottest stars are blue!
The surface temperature of our sun is 5777
Kelvins (~5000 degrees C or
~ 9940 degrees F). The surfaces of the hottest
starts can be 10 times
hotter than the sun! The center of stars is even
hotter than their
No, the Sun is not the hottest star in the
universe. In fact, it's
not very hot at all compared to the population
of stars in the Milky
Way galaxy. One way astronomers measure the
temperature of stars is
by analyzing the light that comes from them:
hotter stars burn at
blue-UV wavelengths, while cooler stars burn at
wavelengths. Our star (the Sun) burns at ~5500
C, and is
approximately 'white'. When you look at stars
in the night sky, you
can guess their temperature based on their
color. Any star that looks
blue is burning much hotter than a red star.
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