What is the oldest white dwarf star?
Extremes
| Title | Star | Date |
|---|---|---|
| Farthest extant | ||
| Oldest | WD 0346+246 SDSS J110217.48+411315.4 | 2012 |
| Youngest | SDSS J0003+0718 | 2011 |
| Highest surface temperature | RX J0439.8−6809 | 2015 |
What is the whitest star?
The coolest stars are the red dwarfs/red giants, with surface temperatures of 3,500 Kelvin or less. As the surface temperature gets hotter, the color of the star turns orange, and then yellow-orange, and then yellow, yellow-white, and then around 5,800 Kelvin it appears white.
What are the names of the dwarf stars?
Notable small stars
| Star name | Star mean radius, kilometres | Star class |
|---|---|---|
| TRAPPIST-1 | 84180 | Red dwarf |
| Teegarden’s Star | 88354 | |
| Luyten 726-8 (A and B) | 97000 | |
| Proxima Centauri | 101000 |
What was the first white dwarf discovered?
Sirius
Is Sirius a white dwarf?
Sirius B, a white dwarf, is very faint because of its tiny size, only 12 000 kilometres in diameter.
What if our sun was a white dwarf?
If you were to form a white dwarf right now, at 20,000 K, and give it 13.8 billion years to cool down (the present age of the Universe), it would cool down by a whopping 40 K: to 19,960 K. We’ve got a terribly long time to wait if we want our Sun to cool down to the point where it becomes invisible.
Will Earth’s 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.
What if the sun was a black dwarf?
That is, if the Sun turned into a black dwarf instantly, which is unlikely even for our hypothetical scenario. From the main-sequence star it is now, the Sun would expand into a red giant, fade out to a white dwarf state, and only then cool down to become a black dwarf. At the red giant stage, it would bake the Earth.
Why are all white dwarfs close to the sun?
White Dwarf Stars. A white dwarf is what stars like the Sun become after they have exhausted their nuclear fuel. Near the end of its nuclear burning stage, this type of star expels most of its outer material, creating a planetary nebula. Only the hot core of the star remains.