Astronomers discover missing matter
Newfound hot stuff helps balance out cosmic accounting
ESA/XMM-Newton/ EPIC/ ESO (J. Dietrich)/ SRON (N. Werner)/ MPE (A. Finoguenov)
Scientists observed a filament connecting two clusters of galaxies, Abell 222 and Abell 223, shown in this composite optical and X-ray image.
Space.com
• Astrium Seeks 24.5 Million Euros from Conax
• Piece of Missing Cosmic Matter Found
• Scientists Revisit Mars Sample Return Plans
• Space Fleets Stay In Formation Magnetically
• Image of the Day: The Frost Report
Related stories
Cosmic lenses reveal far-away galaxies
Most popular
• Most viewed
• Top rated
• Most e-mailedChina: Quake left 18,000 buried in one city
Passenger sues airline over flight spent on toilet
Kristi skates back to the top on ‘Dancing’
Seal caught on tape molesting a penguin
Couple accused of using child as dominatrix
Woman who saved kids from Holocaust dies
Plastic cornea helps blind dog see again
Rare Cayman blue iguanas found slaughtered
More than 300 arrested in immigration raid
Passenger sues airline over flight spent on toilet
Seal caught on tape molesting a penguin
China: Quake left 18,000 buried in one city
‘People foods’ that can kill your pet
Marijuana may up heart attack, stroke risk
By Andrea Thompson
updated 2:13 p.m. CT, Mon., May. 12, 2008
Astronomers have found a piece of the universe's puzzle that's been missing for awhile: a type of extremely hot, dense matter that is all but invisible to us.
Engaging in something like cosmic accounting, astronomers have tried to balance the scant amount of matter that has been directly observed with the vast amount that remains unobserved directly. The latter constitutes about 90 percent of the universe's matter.
Galaxies, the stars within them, the planet we live on and the chairs we sit on are made up of normal matter — the protons, electrons and neutrons that are collectively called baryons. Baryonic matter can be seen and directly observed, but it makes up only about 4 percent of the universe.
advertisement
The rest of the universe is split up between dark matter (about 21 percent), a mysterious type of matter that has yet to be identified but that is thought to have played a critical role in the development of the first galaxies that formed after the Big Bang, and the even more mysterious dark energy (about 75 percent of the universe), which causes the accelerated expansion of the universe.
No comments:
Post a Comment