How long is a star visible after it dies?
These stars are usually no more than about 10,000 light years away, so the light we see left them about 10,000 years ago. Most stars will “live” for somewhere in the neighborhood of 1 billion years, so the odds are low that any particular star died during the past 10,000 years.
What are the remains of dead stars?
Image via The Hubble Heritage Team (AURA/ STScI/ NASA). White dwarfs are the hot, dense remnants of long-dead stars. They are the stellar cores left behind after a star has exhausted its fuel supply and blown its bulk of gas and dust into space.
What do dying stars produce?
When the helium fuel runs out, the core will expand and cool. The upper layers will expand and eject material that will collect around the dying star to form a planetary nebula. Finally, the core will cool into a white dwarf and then eventually into a black dwarf.
What is formed from the remains of dead and dying stars?
supernova remnant The clouds of gas and debris surrounding a star that exploded long ago. The strong magnetic fields inside these remnants accelerate protons to very high speed, creating cosmic rays.
How long does it take for the light from a star to reach Earth?
Other Galaxies
| Object | Time for the Light to Reach Us |
|---|---|
| Alpha Centauri (nearest star system) | 4.3 years |
| Sirius (brightest star in our sky) | 9 years |
| Betelgeuse (bright star) | 430 years |
| Orion Nebula | 1500 years |
Which star color is the hottest?
Blue stars
White stars are hotter than red and yellow. Blue stars are the hottest stars of all.
How was human born?
The first human ancestors appeared between five million and seven million years ago, probably when some apelike creatures in Africa began to walk habitually on two legs. They were flaking crude stone tools by 2.5 million years ago. Then some of them spread from Africa into Asia and Europe after two million years ago.