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Meteorite dates lunar volcanoes

Started by Rick, Dec 07, 2007, 17:49:19

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Rick

Volcanoes were active on the Moon's surface soon after it was formed, a new study in the journal Nature suggests.

Precision dating of a lunar rock that fell to Earth shows our satellite must have had lava erupting across its vast plains 4.35 billion years ago.

This is hundreds of millions of years earlier than had been indicated by the rocks collected by Apollo astronauts.

More: http://news.bbc.co.uk/2/hi/science/nature/7128000.stm

Rick

A meteorite which ploughed into the Peruvian countryside last year should have shattered and dispersed long before reaching the ground.

That is the conclusion of scientists who have been examining samples of the space rock and the 15m-wide crater it dug out in Carancas last September.

The discovery of a water-filled hole, following reports of a fireball in the sky, made headlines around the world.

More: http://news.bbc.co.uk/1/hi/sci/tech/7292863.stm

Rick

#2
A rare type of meteorite that could hold clues to the birth of our Solar System has been bought by London's Natural History Museum.

The Ivuna meteorite, obtained from a US private collection, has the same chemical make-up from which the Solar System formed 4.5 billion years ago.

It landed in Tanzania in 1938 as one 705g stone, since split into samples.

Pieces from the UK sample, the largest in any public collection in the world, will be removed for study.

Most Ivuna samples are held in private collections, or by the Tanzanian government.

More: http://news.bbc.co.uk/2/hi/science/nature/7464583.stm

NHM: http://www.nhm.ac.uk/about-us/news/2008/june/news_14783.html

Rick

 A "unique" micrometeorite found in Antarctica is challenging ideas about how planets can form.

Detailed analysis has shown that the sample, known as MM40, has a chemical composition unlike any other fragment of fallen space rock.

This, say experts, raises questions about where it originated in the Solar System and how it was created.

More: http://news.bbc.co.uk/2/hi/science/nature/7985788.stm

Rick

Formic acid, a molecule implicated in the origins of life, has been found at record levels on a meteorite that fell into a Canadian lake in 2000.

Cold temperatures on Tagish Lake prevented the volatile chemical from dissipating quickly.

An analysis showed four times more formic acid in the fragments than has been recorded on previous meteorites.

More: http://news.bbc.co.uk/2/hi/science/nature/8068049.stm

Rick

A storm of meteorites that pounded Earth and Mars four billion years ago may have made the planets warmer and wetter.

Researchers superheated younger space rocks to measure the gases that would have been shed as meteorites entered fledgling atmospheres during the storm.

There would have been enough to create warmer and wetter planets more amenable to life, they say.

More: http://news.bbc.co.uk/2/hi/science/nature/8079796.stm

Rick

By slamming materials together, scientists have made a mineral that is found naturally only in meteorites and the deep layers of Earth's mantle.

Their successful "shock" experiment reveals new clues about the formation of our early Solar System.

More: http://news.bbc.co.uk/1/hi/sci/tech/8194292.stm

Rick

Scientists say that a meteorite that crashed into Earth 40 years ago contains millions of different carbon-containing, or organic, molecules.

Although they are not a sign of life, such organic compounds are life's building blocks, and are a sign of conditions in the early Solar System.

It is thought the Murchison meteorite could even be older than the Sun.

More: http://news.bbc.co.uk/1/hi/sci/tech/8516319.stm

Rick

Posted in uk.sci.astronomy by Bjørn Sørheim:

A new chondritic brecciated meteorite was found in the eastern part of Oslo on Sunday March 11.
It had gone through the roof of a small cabin on the Rodeløkka allotment gardens.
It is uncertain when it fell, as the cabin was first checked out for the season on Sunday.
But many thinks it fell in the evening of March 1st as a large fireball fragmented over this part of Norway at the time.
The weight is 585g and it broke in two parts as it went through the roof.


Pictures: http://www.vg.no/bildespesial/spesial.php?id=8728

Rick

Cosmochemist discovers potential solution to meteorite mystery

A normally staid University of Chicago scientist has stunned many of his colleagues with his radical solution to a 135-year-old mystery in cosmochemistry.

British mineralogist Henry Sorby first described these spherules, called chondrules, in 1877. Sorby suggested that they might be "droplets of fiery rain" which somehow condensed out of the cloud of gas and dust that formed the solar system 4.5 billion years ago.

Grossman's research reconstructs the sequence of minerals that condensed from the solar nebula, the primordial gas cloud that eventually formed the sun and planets. He has concluded that a condensation process cannot account for chondrules. His favorite theory involves collisions between planetesimals, bodies that gravitationally coalesced early in the history of the solar system.

More

Rick

Early Solar System Garnet-like Mineral Named For Livermore Cosmochemist (Hutcheonite)

A recently discovered mineral appears to be clear but may have a tinge of light blue. No matter its color, you won't be able to make earrings from it.

For one, you can't see the material with the naked eye. Hutcheonite, recently named after Lawrence Livermore meteorite researcher Ian Hutcheon, can be seen only with high powered scanning electron microscopes.

Known also by its chemical makeup, Ca3Ti2SiAl2O12, hutcheonite was discovered in a refractory inclusion in the Allende meteorite by Sasha Krot (University of Hawaii) and Chi Ma (Caltech) and named in honor of Hutcheon, who has made numerous contributions to the study of meteorites and what they can tell us about the evolution of the early solar system.

More: https://www.llnl.gov/news/newsreleases/2013/Aug/NR-13-08-02.html

Rick

Study questions dates for cataclysms on early Moon, Earth

Phenomenally durable crystals called zircons are used to date some of the earliest and most dramatic cataclysms of the solar system. One is the super-duty collision that ejected material from Earth to form the moon roughly 50 million years after Earth formed. Another is the late heavy bombardment, a wave of impacts that may have created hellish surface conditions on the young Earth, about 4 billion years ago.

Both events are widely accepted but unproven, so geoscientists are eager for more details and better dates. Many of those dates come from zircons retrieved from the moon during NASA's Apollo voyages in the 1970s.

A study of zircons from a gigantic meteorite impact in South Africa, now online in the journal Geology, casts doubt on the methods used to date lunar impacts. The critical problem, says lead author Aaron Cavosie, a visiting professor of geoscience and member of the NASA Astrobiology Institute at the University of Wisconsin-Madison, is the fact that lunar zircons are "ex situ," meaning removed from the rock in which they formed, which deprives geoscientists of corroborating evidence of impact.

More: http://news.wisc.edu/24103