WE FINALLY KNOW WHY THE BOOMERANG NEBULA IS COLDER THAN SPACE ITSELF

[Judi Lynn]

Scientists may now know why the Boomerang Nebula, the coldest object in the known Universe.
Credit: NASA/ESA/The Hubble Heritage Team (STScI/AURA)

Article Updated: 6 Jun , 2017
by Matt Williams


The Boomerang Nebula, a proto-planetary nebula that was created by a dying red giant star (located about 5000 light years from Earth), has been a compelling mystery for astronomers since 1995. It was at this time, thanks to a team using the now-decommissioned 15-meter Swedish-ESO Submillimetre Telescope (SESTI) in Chile, that this nebula came to be known as the coldest object in the known Universe.

And now, over 20 years later, we may know why. According to a team of astronomers who used the Atacama Large Millimeter/submillimeter Array (ALMA) – located in the Atacama desert in northern Chile – the answer may involve a small companion star plunging into the red giant. This process could have ejected most of the larger star’s matter, creating an ultra-cold outflow of gas and dust in the process.

The team’s findings appeared in a paper titled “The Coldest Place in the Universe: Probing the Ultra-cold Outflow and Dusty Disk in the Boomerang Nebula“, which appeared recently in the Astrophysical Journal. Led by Raghvendra Sahai, an astronomer at NASA’s Jet Propulsion Laboratory, they argue that the rapid expansion of this gas is what has caused it to become so cold.

More:
https://www.universetoday.com/135920/finally-know-boomerang-nebula-colder-space/

[SergeStorms]

1. ..."the coldest object in the known Universe".

I'd like to nominate Malaria Trump for that dubious "honor". The way she forcefully rejected Donnie Dumbass's moves to appear as the "happy couple" on their recent trip abroad, was very cold indeed. It made Donnie Dumpster look like a complete fool, especially to Republicans who pride themselves on being able to "handle their women".

I'm not trying to take anything away from this wonderful discovery about the Boomerang Nebula, but I thought interjecting a little humor (OK, VERY little) might make a rather dry subject more palatable. So sue me.

[rpannier]

2. Very, Very Cool

Save to read article later

[Javaman]

3. so cold, so very cold

[ProfessorPlum]

4. Very cool

It's the same reason we purse our lips to cool our soup: expanding gas cools.

[mr_lebowski]

5. So does evaporation ...

I think most (if not all) of the cooling action in the instance you describe is due to increasing the rate of evaporation rather than gas decompression, but I may be wrong ...

[ProfessorPlum]

6. that's probably correct

especially with a piping hot liquid which has a high vapor pressure to begin with ...

[Maynar]

7. She's so cold