* Astronomy

Members Login
Post Info
TOPIC: Meteorites


L

Posts: 131433
Date:
RE: Meteorites
Permalink  
 


Meteorites: Life, Death, and Hope on Earth | Geoff Notkin | TEDxInstitutLeRosey

Spoiler



__________________


L

Posts: 131433
Date:
Permalink  
 

Title: Small Near-Earth Asteroids as a Source of Meteorites
Author: Jirí Borovicka, Pavel Spurný, Peter Brown

Small asteroids intersecting Earth's orbit can deliver extraterrestrial rocks to the Earth, called meteorites. This process is accompanied by a luminous phenomena in the atmosphere, called bolides or fireballs. Observations of bolides provide pre-atmospheric orbits of meteorites, physical and chemical properties of small asteroids, and the flux (i.e. frequency of impacts) of bodies at the Earth in the centimeter to decameter size range. In this chapter we explain the processes occurring during the penetration of cosmic bodies through the atmosphere and review the methods of bolide observations. We compile available data on the fireballs associated with 22 instrumentally observed meteorite falls. Among them are the heterogeneous falls Almahata Sitta (2008 TC3) and Beneov, which revolutionised our view on the structure and composition of small asteroids, the Pribram-Neuschwanstein orbital pair, carbonaceous chondrite meteorites with orbits on the asteroid-comet boundary, and the Chelyabinsk fall, which produced a damaging blast wave. While most meteoroids disrupt into fragments during atmospheric flight, the Carancas meteoroid remained nearly intact and caused a crater-forming explosion on the ground.

Read more (1315kb, PDF)



__________________


L

Posts: 131433
Date:
Permalink  
 

Study shows how planetary building blocks evolved from porous to hard objects

Thinking small has enabled an international team of scientists to gain new insight into the evolution of planetary building blocks in the early solar system. The researchers compared the results of small-scale numerical simulations of colliding rock and dust particles to the composition of meteorites. They found that collisions helped transform initially porous materials into the more highly solidified asteroids and meteorites observed today.
Read more



__________________


L

Posts: 131433
Date:
Permalink  
 

Meteorites Treated By Different Cultures in Unique Ways

Meteorites were regarded as messages from God in historic times and were considered good or bad omens depending on the culture and social environment.
Read more



__________________


L

Posts: 131433
Date:
Black Market Meteorites
Permalink  
 


Illegal Meteorite Trade Surges, Angering Geologists

The problem, of course, is that these treasures of science are winding up in the hands of collectors, and not actual scientists. Interest from meteorite hobbyists is relatively new, spurred by the discovery of rare meteorites from the Moon and Mars found in Libya. These prized rocks can fetch serious money online.
A quick search on eBay shows that yes, indeed, there are literally hundreds of meteorites on sale as we speak. Most are less than $100, but some can go for thousands.

Read more 



__________________


L

Posts: 131433
Date:
RE: Meteorites
Permalink  
 


When young Antoine-Laurent Lavoisier was sent in 1768 to the Pays de la Loire to investigate a rock, the report he sent to the Académie Royale des Sciences poured scorn on the "highly dubious" notion that the triangular stone weighing 3.5 kilograms had fallen from the skies, as witnesses had claimed. After all, luminaries from Aristotle to Sir Isaac Newton had declared that the stars and planets of the heavenly realm move freely without the encumbrances of ordinary matter.
But just 35 years later, when Jean-Baptiste Biot conducted a nine-day investigation of a similar event, his interviews with the citizens of Normandy allowed him to describe the arrival of a fragment from space at a declination of 22 degrees, which he suggested had originated from the moon.

Read more

__________________


L

Posts: 131433
Date:
New Zealand Meteorites
Permalink  
 


While you're still in the city head to Nando's at 328 Queen St before nipping up One Tree Hill to view the night sky at the Stardome Observatory.
Have a look around before the show starts so you don't miss the Nuevo Mercurio meteorite, the Northern Territory meteorite, and meteorites that have landed here in New Zealand.

Read more

__________________


L

Posts: 131433
Date:
RE: Meteorites
Permalink  
 


Meteorite falls are those meteorites that were witnessed by people or automated devices as they moved through the atmosphere or hit the Earth, and were subsequently collected. All other meteorites are meteorite finds. As of April 2010, there are about 1,087 documented falls that are listed in widely used databases, most of which have specimens in modern collections.
Read more

__________________


L

Posts: 131433
Date:
Permalink  
 

Valley students find meteorites in Selinsgrove

Want to see a meteorite? Don't look up. Look down -- specifically where your rain spout ends, because that's where particles of meteorites are likely to be.
Read more

__________________


L

Posts: 131433
Date:
Permalink  
 

Exhibition of meteorites in the Museum of Technology in Warsaw

See more

__________________
1 2 39  >  Last»  | Page of 9  sorted by
Quick Reply

Please log in to post quick replies.



Create your own FREE Forum
Report Abuse
Powered by ActiveBoard