Solar System May Be Older Than Thought
2010 08 24
By Mike Wall | Space.com
The solar system may be up to two million years older than previously thought, a new study has found.
Researchers studying bits of a meteorite discovered that the space rock was 4.5682 billion years old, predating previous estimates of the solar systemís age by up to 1.9 million years. This adjustment, though ever so slight, should help astronomers better understand how the sun and planets formed.
"We believe that, right now, this is the most precise and accurate date for the age of the solar system," said study co-author Meenakshi Wadhwa of Arizona State University.
Meteorite detective story
Wadhwa and colleague Audrey Bouvier, also of ASU, made the find while studying a meteorite called NWA 2364, which fell to Earth in Morocco in 2004. They examined a 1-centimeter chunk of the meteorite known as a calcium-aluminum-rich inclusion, or CAI.
Inclusions are minerals that get trapped inside meteorites as the space rocks are forming. Scientists believe CAIís were among the first solids to condense out when the sun and planets were forming, so CAI ages are good representations of the solar systemís age.
Wadhwa and Bouvier used lead-lead dating, a technique commonly used to date meteorites, to figure out the CAIís age. They measured the abundances of three lead isotopes - versions of the element with different atomic masses - in the CAI. Two of the lead versions form when uranium isotopes radioactively decay; the other one is not a decay product.
Comparing the amounts of the three lead isotopes, and relating those numbers to the known rates of uranium-isotope decay, gave the researchers their answer: 4.5682 billion years.
This number is only a hair older than previous estimates of the solar systemís age, which were chiefly gleaned from dating CAIís in other meteorites. But the difference is real, according to Wadhwa.
"Thatís the power of geochemistry," she told SPACE.com. "You can make very, very precise measurements."
Age of the solar system
And even such small adjustments to the solar systemís age can be very important to astronomers seeking to understand how the sun and planets formed.
As an example, Wadhwa and Bouvier cite the abundance of the isotope iron-60 in the proto-solar system. Iron-60 is radioactive, with a half-life of about 2.6 million years. Every 2.6 million years, half of the iron-60 in a given sample decays away.
So if you push the age of the solar system back by about two million years, that means there was almost twice as much iron-60 present during its birth than previously thought. And this increased concentration has consequences: it strongly supports the idea that a supernova exploded nearby during the solar systemís formation, injecting huge quantities of heat that helped nascent bodies differentiate.
"Iron-60 is kind of a smoking gun," Wadhwa said. "If present in certain abundances, it can only really be there because of a supernova injection."
Astronomers can do this sort of sleuthing with many different isotopes that have relatively short half-lives. So nailing down the solar systemís age precisely is key.
"It gives us a better understanding of the type of environment the solar system evolved in," Wadhwa said.
The researchers report their findings Aug. 22 in the online version of Nature Geoscience.
Article from: Space.com
Hypergeometry, Astrology and the Spaces Inbetween (Video)
Violent spacequakes shake Earth from above
Age Confirmed for íEve,í Mother of All Humans
New Find Pushes Age of Stone Tools Back A Million Years!
Revised theory of gravity doesnít predict a Big Bang
Big Bang experiment may reveal dark universe: CERN
Andrew Lange, physicist who explored remnants of Big Bang, dies at age 52
Latest News from our Front Page
Agenda 21: The BLM Land Grabbing Endgame
2014 04 23
Why is the federal government so obsessed with grabbing more land? After all, the federal government already owns more than 40 percent of the land in 9 different U.S. states.
Why are federal bureaucrats so determined to grab even more? Well, the truth is that this all becomes much clearer once you understand that there is a ...
Fukushima radiation killing children, government hiding the truth
2014 04 22
Katsutaka Idogawa, former mayor of Futaba, a town near the disabled Fukushima nuclear plant, is warning his country that radiation contamination is affecting Japanís greatest treasure - its children.
Asked about government plans to relocate the people of Fatuba to the city of Iwaki, inside the Fukushima prefecture, Idogawa criticized the move as a "violation of human rights."
Compared with Chernobyl, radiation ...
Why your fingerprints may not be unique
2014 04 22
Assumption that everyone has a unique fingerprint from which they can be identified through a computer database is flawed, says Home Office expert Mike Silverman
Fingerprint evidence linking criminals to crime scenes has played a fundamental role in convictions in Britain since the first forensic laboratory was set up in Scotland Yard in 1901.
But the basic assumption that everyone has a ...
Asteroids cause dozens of nuclear-scale blasts in Earthís atmosphere
2014 04 22
Asteroids caused 26 nuclear-scale explosions in the Earthís atmosphere between 2000 and 2013, a new report reveals.
Some were more powerful Ė in one case, dozens of times stronger Ė than the atom bomb blast that destroyed Hiroshima in 1945 with an energy yield equivalent to 16 kilotons of TNT.
Most occurred too high in the atmosphere to cause any serious damage ...
ĎEditing DNAí to eliminate genetic conditions now a reality
2014 04 22
Scientists have employed a revolutionary genome-editing computer technique that accurately identifies one faulty genetic ďletterĒ among billions and effortlessly repairs a genetic condition in animals, paving way for human trials.
The success, by MIT in Boston, is the latest achievement in the field of genome editing that has been catapulted into the spotlight through a technology that can pinpoint genetic faults ...
|More News Ľ |