On a dark night, you can see thousands of stars in the sky, creating a vast and expansive cosmic tableau, along with clouds, dust, planets, and stars are a fascinating subject for science enthusiasts.
The oldest star in the universe
Determining the age of a star is based on the analysis of its spectrum. The oldest star found to date is SMSS J031300.36-670839.3, with an age of 13.6 billion years. Scientists believe that there may still be stars similar to or older than SMSS J031300.36-670839.3, but finding them among the millions of stars in the universe is extremely difficult.
The brightest and heaviest star in the universe
The star R136a1 is known as the brightest and heaviest star in the universe today. This star is 8.7 million times brighter, 70 times larger in diameter, and 265 times heavier than the Sun. R136a1 is located 165,000 light-years away from Earth and can emit solar winds with speeds of 2,600 km/h.
The dimmest star in the universe
During the lifetime of stars, after their shining phase, they will gradually dim, deplete their energy, and become a brown dwarf star. The dimmest star we have found at this time is 2MASS J0523-1403. Of course, in the future, 2MASS J0523-1403 may become a brown dwarf star and pass this record to another star. However, scientists have not yet discovered any brown dwarf stars at this time.
The largest star in the universe
The largest star in the universe today has a diameter 1,708 times that of the Sun, known as UY Scuti. This star has an approximate diameter of 1.2 billion kilometers and a circumference length of up to 7.5 billion kilometers. To imagine the enormity of UY Scuti, you can think that it would take about 950 years on a commercial airplane to fly around it.
The smallest star in the universe
EBLM J0555-57AB, with a size equivalent to that of Earth (radius approximately 58,232 km), is the smallest star in the triple star system EBLM J0555-57 and is also the smallest star known at this time. EBLM J0555-57AB is about 600 light-years away from Earth.
The hottest star in the universe
When a star reaches its maximum temperature, it will explode and become a supernova. Then, what remains can be a neutron star or a black hole. Eta Carinae, with a temperature of up to 40,000 degrees Celsius, is considered the hottest star at the moment. Scientists believe it could explode and become a supernova at any time.
The coldest star in the universe
If you often hear that stars emit light due to their extremely high temperatures, you may be surprised to learn that the brown dwarf star WISE J085510.83-071442.5 has temperatures ranging from -13 to -47 degrees Celsius. Some other brown dwarf stars have temperatures equal to Earth’s room temperature.