How old is the oldest white dwarf?
Table of Contents
How old is the oldest white dwarf?
Extremes
| Title | Star | Data |
|---|---|---|
| Nearest | Sirius | 8.6 ly (2.6 pc) |
| Farthest | SN UDS10Wil progenitor | 10,000,000,000Ly z=1.914 |
| Oldest | WD 0346+246 SDSS J110217.48+411315.4 | 12 Gy (tired) |
| Youngest | SDSS J0003+0718 | < 13 My |
What is the life cycle of a white dwarf?
A star like our Sun will become a white dwarf when it has exhausted its nuclear fuel. Near the end of its nuclear burning stage, such a star expels most of its outer material (creating a planetary nebula) until only the hot (T > 100,000 K) core remains, which then settles down to become a young white dwarf.
Why do white dwarfs last so long?
The more surface area it has the more energy it can dissipate in a given time for a given temperature. Furthermore, as a white dwarf cools its surface temperature decreases which further slows the rate of cooling. This means that white dwarfs will stay warm for many billions of years.
Are white dwarfs hot?
A white dwarf is very hot when it forms, but because it has no source of energy, it will gradually cool as it radiates its energy away. This means that its radiation, which initially has a high color temperature, will lessen and redden with time.
How cold is the coldest white dwarf?
3,000 degrees Kelvin
The researchers calculated that the white dwarf would be no more than a comparatively cool 3,000 degrees Kelvin (2,700 degrees Celsius). Our Sun at its center is about 5,000 times hotter. Astronomers believe that such a cool, collapsed star would be largely crystallized carbon, not unlike a diamond.
Can a white dwarf turn into a black hole?
White dwarfs are thought to be the final evolutionary state of stars whose mass is not high enough to become a neutron star or black hole. This includes over 97\% of the other stars in the Milky Way.
Will our sun become a white dwarf?
Like the vast majority of stars in our Milky Way galaxy, the sun will eventually collapse into a white dwarf, an exotic object about 200,000 times denser than Earth. “The sun itself will become a crystal white dwarf in about 10 billion years.”
How long do white dwarfs stay hot?
Furthermore, as a white dwarf cools its surface temperature decreases which further slows the rate of cooling. This means that white dwarfs will stay warm for many billions of years. In fact, they cool so slowly that the Universe isn’t old enough to contain any that have cooled off completely, becoming ‘black dwarfs’.