Nearby Star Smaller than Earth, Massive as Sun

space.com ^ | 12/13/05 | Robert Roy Britt

[KevinDavis]

The brightest star in our sky has a companion that’s smaller than Earth yet 98 percent as massive as the Sun, a new study reveals.

Astronomers already knew the brilliant blue-white Sirius had a stellar companion. But they didn’t know the object’s mass. The new measurement, announced today, was done by an international team of astronomers using the Hubble Space Telescope.

Sirius is one of the closest known stars at 8.6 light-years away. It is twice as massive as the Sun and has a surface temperature of 18,000 degrees Fahrenheit (10,000 degrees C).

The companion, called Sirius B, was known to be much hotter. It is the scorching ember of a Sun-like star now called a white dwarf, and it’s the nearest of its kind. It was discovered in 1862 but close scrutiny is difficult because of the glare of the primary star.

“Studying Sirius B has challenged astronomers for more than 140 years," said Martin Barstow of the University of Leicester, U.K.

[KevinDavis]

[manwiththehands]

The new measurement, announced today, was done by an international team of astronomers using the Hubble Space Telescope.

If it's still so useful someone tell me again why we are letting the Hubble die?

[Batrachian]

"If it's still so useful someone tell me again why we are letting the Hubble die?"

There aren't enough shuttle missions available to keep Hubble running. But, you can look forward to the Next Generation Space Telescope, now known as the James Webb Space Telescope, unless it's canceled.

[sagar]

Aren't these types of stars called Binary Stars?

[COEXERJ145]

The companion, called Sirius B...

Also referred to as "The Pup".

[clyde asbury]

There's a good set of articles in January's issue of Sky & Telescope called "NASA's Other Space Telescopes."

It details the Chandra, GALEX, Spitzer, and Swift space telescopes - all still in operation. They don't require servicing as Hubble does.

[manwiththehands]

I've never heard of the James Webb 'scope. I'll look it up on the web. I'm just very, very fond of all the incredible information the Hubble has given us and hate to see it go.

[Job03]

Surely you can't be Sirius (B)! Nice photo on NASA site:

http://apod.gsfc.nasa.gov/apod/ap001006.html

[Gordongekko909]

Volume of Earth, mass of two Sols? That is wicked dense.

[Brilliant]

White dwarfs are involved in explosions called Type Ia supernovas, which are used to measure cosmological distances and the universe’s rate of expansion.

Apparently, it is a close call whether the white dwarf orbiting Sirius is big enough to create a supernova. If so, then it may wipe out all life on earth because it is so close. On the other hand, most of the astronomers say it's not quite big enough.

[Young Werther]

Howard Stern was interviewed by O'Reilly. He will soon become the highest paid entertainer when he becomes a Sirius Star!!

[timer]

At c^2 in a super-momentum state, sirius B is about 15 minutes away(105 sec/LY). This is from DeBroglie's equation : u=c^2/v Wanna go?

[Lancer_N3502A]

You beat me to that one.

[Wilhelm Tell]

Surely you can't be Sirius (B)!

Don't call me Shirley. I'm Sirius!
(Bad puns, I can't help myself.)

[Armigerous]

I think Sirius also has a companion 'dark star' named Nemesis

[Itzlzha]

The companion, called Sirius B, was known to be much hotter. It is the scorching ember of a Sun-like star now called a white dwarf, and it’s the nearest of its kind.

I prefer Dwarfs to be of the "Red" variety...

[Wilhelm Tell]

When Sirius comes around this time of year it always gives me pause for introspection. Sometimes I will look up that star and try to think about what was going on in the world and in my life around 8 1/2 years ago. Somehow that mental exercise helps me to put things in perspective. It helps me clarify things better than making a New Year's resolution can. Does anyone else have thoughts like that or does this sound hopelessly weird or nerdy?

[JohnCliftn]

I think it is because NASA figures we won't let it die. The Hubble has always been great PR and the mother lode for scamming contractors.

I doubt that the initial optical problem was on the up and up, since the contractors got rewarded for it by being paid to fix it.

Similarly, the cry will ring out, "Save Hubble". NASA will reply "No Money in Budget". "Save Hubble" crowd will speak of Hubble as if it were a cute little furry thing, so cuddly, endangered, and it will Burn, Burn, Burn a horrible end unless The Government Does Something, namely gives NASA more loot.

Some of us know Private Enterprise would open Space faster, better, more efficiently, and at a fair profit to investors provided the investors are willing to wait a long time for the payback.

We'll probably lose this one. "Save Hubble" will result in NASA getting more loot, most likely.

If the copyrights and patents clause of the US Constitution was recognized under law as applying to basic research as will as final products, we'd have profitable private research of all types already.