Download presentation
1
METEORITES – What are they?
Meteorites are chunks of extra-terrestrial matter from outer space that land on Earth. Background photo: 512 x 512 pixels. (Another astronomy picture of the day [apod], this one from January 26, Again, this one is probably out of the archives). Rocks from Outer Space!
2
Where do they come from? Most meteorites come from the asteroid belt that exists between the orbits of Mars and Jupiter. Collisions between asteroids can create more debris as well as knock some of this material out of the asteroid belt. This debris may get trapped in the gravitational pull of the Earth’s orbit and come slamming down onto the ground. Meteorites have also come from Mars and the Moon. Background Photo: Perseid Meteor Shower. (This is an astronomy picture of the day [apod] from the NASA? Apod archives. It was taken August 10, When going to this location, click on the large image to get the the even larger one) x 1422 pixels.
3
How do they get here? When this debris enters the Earth’s atmosphere, they turn into “shooting stars” or “meteors” and look like a white or bright streak of light that is hurtling across the sky. Since most meteors burn up in the atmosphere before they ever touch the ground, they usually don’t produce meteorites. Only the really big and bright meteors, the “bolides” or “fireballs”, have enough rocky stuff left over. Background photo: 600 x 432 pixels Leonid Meteor shower pictures on this website, first picture, 2nd row. Nov. 18, (Find photo under “Special Photos – Nov. 18 Leonid Showers” section on bottom left side of page.)
4
What are they made of? Meteorites from the asteroid belt are usually chondrites (or stony meteorites) and are most often made up of nickel-iron metal, pyroxene, and olivine. Background Photo: (go to the Astronomy page and the Leonid Meteor Shower picture is about halfway down the page) x 749 pixels. (Picture taken November 18, The meteor shower picture as taken in Franklin, Massachusetts, USA. Location: 42.1 N, 71.4 W) Foreground Photo left: Foreground Photo right:
5
Can you find the meteorite?
Background Photo: Play the “Find the Meteorite” in this photo.
6
How well did you do? Background Photo: This page contains the answer and shows which ones are meteorites or possible meteorites and which ones aren’t.
7
Martian Meteorites
8
How do we know they’re from Mars?
From spectroscopic measurements, we know the chemical composition of Mars’ atmosphere. The chemical analysis done on the gas inside the rocks matched the chemical composition of Mars’ atmosphere, and voilà, we have Martian meteorites!! Foreground Photo left: (parent site) Foreground Photo right:
9
How did they get here? A huge meteor or comet would have to have violently smashed into Mars surface and blasted off chunks of Mars at speeds of at least 11,000 miles per hour. That’s how fast a rock would have to be going to escape Mars’ gravity and land on earth. Foreground Photo left: (the Los Angeles meteorite) Foreground Photo right:
10
What’s a Lunar meteorite?
Sometimes the moon is hit by passing objects such as asteroids and comets. When an object is big enough and heavy enough, when it crashes into the moon, it can send chunks of the moon flying everywhere. Some of these pieces can land on earth as lunar meteorites, or lunaites . Moon photo: 900 x 720 pixels or Background photo: 700 x 457 pixels Leonid Meteor shower pictures on this website, middle picture, 1st row. Nov. 18, (Find photo under “Special Photos – Nov. 18 Leonid Showers” section on bottom left side of page.)
11
On this lunaite, there are no sharp angles or edges in the portions of the meteorite covered by the fusion crust. But there are ablation scoops and pits. Photo and Text: “Note these additional features that are also characteristic of meteorites, but not of "meteorwrongs:" there are no sharp angles or edges in portions of the meteorite covered by fusion crust the presence of ablation scoops and pits “ (Photos courtesy of Jim Strope)
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.