Star light, star bright. Which star is the brightest star tonight? Better yet, which is the biggest?
It’s not our Sun. This immense ball of burning
Sirius, one of the biggest stars in the universe, is also the brightest in Earth’s nighttime sky. Sirius has a radius of about 745,645 miles, about 71 percent larger than the Sun’s radius. Sirius, about 8.6 light years from Earth, is also about twice as massive and 25 times more luminous than the Sun. Sirius, known as the Big Dog in the Canis Major constellation, gets its name from the Greek word Seirios meaning “glowing.” It played a major part in ancient Egyptian’s history and its calendar system.
Betelgeuse, located about 640 light years from Earth, is among the red supergiants. It’s the ninth brightest star at night and the second brightest star in the Orion constellation. Betelgeuse, which has 20 times more mass than the Sun, has a radius of about 509,959 miles. That’s 1,200 times the radius of the Sun.
Part of Betelgeuse’s brightness comes from the fact that it’s nearing the end of its life and is due to explode. It will likely run out of fuel, expand under its weight, and rebound in a supernova explosion. That will mean quite a bright Betelgeuse for up to a few months, possibly as bright as our moon, but scientists don’t believe the supernova will be close enough to Earth to affect us in any way but giving us a thrilling light show.
8. RW Cephei
RW Cephei, one of the biggest stars in the universe, sits in the constellation Cepheus. Based in solar radii, a measurement centered around the Sun with the Sun equaling one, RW Cephei is an estimated 1,636 solar radii.
That’s bigger than the orbit of Jupiter.
7. KY Cygni
KY Cygni, which lies about 5,000 light years away from earth, has an estimated radius of 1,420 times that of the Sun. It’s about 300,000 times as luminous as the Sun. The red supergiant star is located in the constellation Cygnus.
6. Pistol Star
The Hubble Space Telescope discovered the Pistol Star in 1991. It’s one of the biggest stars in the universe and one of its most radiant. The star’s mass is about 80 to 150 times greater than that of the Sun. What it emits in energy in 20 seconds is thought to be as equal to the energy put out by the Sun in a year.
5. WOH G64
The red hypergiant star WOH G64 lies in the southern constellation of Dorado in the Large Magellanic Cloud satellite galaxy. it lies 168,000 light years away from Earth and has a radius of about 1,540 times that of the Sun. “WOH” stands for its discovers whom had the last names Westerlund, Olander and Hedin.
4. V838 Monocerotis
This star lies about 20,000 light years from the Sun. Its size is difficult to determine but its radius is somewhere between 380 and 1,970 times the Sun. The star is located near the constellation Monoceros.
3. Mu Cephei
Mu Cephei, a red supergiant star, may possibly be the largest star that you can see with your naked sky. It’s one of the most luminous and biggest stars in the universe and its size is about 1,600 to 1,900 times the radius of the Sun. Mu Cephei is more than 38,000 times as luminous as the Sun.
2. VY Canis Majoris
If placed in the center of the Milky Way solar system, the size of this star would nearly touch the orbit of Saturn. its radius is 1,800 to 2,100 times the radius of the Sun and it is 30 to 40 times as heavy as the Sun, putting out about 500,000 times more light. VY Canis Majoris is about 5,000 light years away.
R136a1, located in the Tarantula Nebula in the Large Magellanic Cloud dwarf galaxy, first drew the attention of astronomers in 2010. It’s the most massive and luminous star ever discovered. It has double the mass of the Pistol Star, making it the most massive star ever. It also dwarfs the Sun in energy, giving out as much energy in five seconds as the Sun does in a year. Its temperature of more than 89,500 F is nearly 10 times hotter than the Sun. Its radius is about 1700 times the Sun’s radius. R136a1 takes the crown as the biggest star in the universe.