Invisible star 'shooting comets at Earth'

An invisible star responsible for the extinction of dinosaurs may be circling the Sun and causing comets to bombard the Earth, scientists said.

• Brown dwarf could have caused mass extinctions
• Star is invisible and a long way away
• But heat-seeking telescope may find it

The brown dwarf - up to five times the size of Jupiter - could be to blame for mass extinctions that occur here every 26 million years, The Sun reports.
The star - nicknamed Nemesis by NASA scientists - would be invisible as it only emits infrared light and is incredibly distant. Nemesis is believed to orbit our solar system at 25,000 times the distance of the Earth to the Sun.

As it spins through the galaxy, its gravitational pull drags icy bodies out of the Oort Cloud - a vast sphere of rock and dust twice as far away as Nemesis.
These "snowballs" are thrown towards Earth as comets, causing devastation similar to the asteroid that wiped out the dinosaurs 65 million years ago.

Now NASA scientists believe they will be able to find Nemesis using a new heat-seeking telescope that began scanning the skies in January.
The Wide-Field Infrared Survey Explorer - expected to find a thousand brown dwarf stars within 25 light years of the Sun - has already sent back a photo of a comet possibly dislodged from the Oort Cloud.

Scientists' first clue to the existence of Nemesis was the bizarre orbit of a dwarf planet called Sedna. Scientists believe its unusual, 12,000-year-long oval orbit could be explained by a massive celestial body.

Mike Brown, who discovered Sedna in 2003, said: "Sedna is a very odd object - it shouldn't be there.

"The only way to get on an eccentric orbit is to have some giant body kick you - so what is out there?"

Professor John Matese, of the University of Louisiana at Lafayette, said most comets come from the same part of the Oort Cloud.

He added: "There is statistically significant evidence that this concentration of comets could be caused by a companion to the Sun."




http://www.news.com.au/features/invisible-star-shooting-comets-at-earth/story-e6frflor-1225840140357

Related Coverage

• First images from high-tech telescope NEWS.com.au, 18 Feb 2010
• Invisible beauties of our skies Daily Telegraph, 18 Feb 2010
• NASA on hunt for distant galaxies Adelaide Now, 15 Dec 2009
• NASA blasts off space mapping satellite NEWS.com.au, 14 Dec 2009
• Green object streaks across sky Courier Mail, 19 Nov 2009

 

If Nemesis is the reason why mass extinctions occur here, we should somehow destroy it...that could prevent other mass extinctions from happening, including humans...right?

 

its too fucking late

 

No we can't destroy it. We need to be destroyed.

 

since it's such a long , long cycle .... we gots plenty of time to save the earth , like several million years . do we stick around and help out ? probably since we are so intimately of this earth we ain't going anywhere else . we'll make some cool robots to deal with it . really , Life is strong . Life has made an animal like us for it's survival . quit yer wankin .

 

The fastest but still very very very long way for this Earth to heal back over would be without human existence on it AT ALL.

 

That isn't an opinion. My opinion is I'd like to live a full life.

 

i cant believe it orbits around the galaxy. Thats amazing. Even if it does happen, who cares?thatd go to show special this fleet? of humans are. We get to depart together! lol...

 

I think we should colonize it.

 

Partially true article is only partially true.

Nemesis was theorized in 1984.

 

As I understand the theory, Nemesis is orbiting at 25,000 AU. It does not directly cause extinctions, but perturbs comets, which are the bodies that interact with Earth.

One problem that I see with the theory is the assumption that one an obit, Nemesis "pushes" comets out of the Oort cloud. And one of those comets interacts with Earth causing a crash in the ecosystem.
I find it hard to believe that the orbital mechanics results in a earth bound comet every one of Nemesis orbits.

The OP sounds like a scientific search for brown dwarfs got mixed with some evolutionary history speculation.

 

Well, from what I understand some of the NASA scientists are hoping they can find proof of Nemesis, through their WISE program.
With a little journalistic spin, this can make Nemesis seem like a wide-believed theory, and NASA's objective.