Have astronomers found a TŻO?
When a big star runs out of fuel, its core can collapse and form a dense ball of neutronium just 25 kilometers across, called a neutron star
. But what happens when a neutron star hits an ordinary star?
Kip Thorne is a physicist who helped write the most famous book on general relativity. Now he's helping run the LIGO project for detecting gravitational waves. Anna Żytkow is an astronomer at Cambridge who is looking for objects in the Kuiper Belt, outside the orbit of Pluto. But back in 1977, they teamed up and asked this question... and answered it!
The answer is: the neutron star could fall to the center of the other star!
The result is called a Thorne–Żytkow object
, or TŻO
When this happens, the neutron star will suck in gas from the ordinary star. It will get extremely hot, with temperatures over a billion degrees Celsius. The heat comes from two things: energy released when infalling gas hits the neutron star, and nuclear fusion after the gas hits.
If all this happens inside a red supergiant star — a huge, puffed-up star — the inside of that star should get a lot hotter than usual. So, weird processes should create elements that you don't usually see in such a star.
And now astronomers have found a red supergiant with a lot more rubidium, strontium, yttrium, zirconium, molybdenum and lithium than usual. We know this from its spectral lines.
So, they may have found a TŻO!
Anna Żytkow was pleased: "I am extremely happy that observational confirmation of our theoretical prediction has started to emerge."
The candidate TZO is called HV 2112
. It's in the the Small Magellanic Cloud, a dwarf galaxy orbiting ours, about 200,000 light-years away.
The astronomer Nidia Morell found the weird elements in this star while conducting a survey of red supergiants last year. At the time she said:"I don't know what it is, but I know that I like it!"
Read all about it here:
Emily M. Levesque, Philip Massey, Anna N. Żytkow and Nidia Morrell, Discovery of a Thorne-Zytkow object candidate in the Small Magellanic Cloud, http://arxiv.org/abs/1406.0001
How do you pronounce a Z with a dot on it? Clue: Anna Żytkow is Polish.Puzzle 2:
What could happen if a neutron star falls to the bottom of a white dwarf, if their total mass is big enough?Puzzle 3:
What could happen if a neutron star falls to the bottom of a white dwarf if their total mass is not
so big?Puzzle 4:
Suppose you have a neutron star inside a red supergiant. What eventually happens to it? Puzzle 5:
Suppose two red supergiants containing neutron stars collide. What happens then?
For more, read this:http://www.space.com/27389-hybrid-star-discovery-thorne-zytkow-object.html
or Wikipedia:https://en.wikipedia.org/wiki/Thorne%E2%80%93%C5%BBytkow_object #spnetwork
arXiv:1406.0001 #astronomy #Thorne