Do more meteorites fall at low latitudes?
Do more, or less, meteorites fall at different latitudes? i.e. do more fall at the equator than at the poles? When I was in Vietnam, I seemed to see many more "shooting stars" than anywhere else I have lived (Alaska to Australia).
I did some reading, and I found that meteor rates do vary by a number of effects, some of which are dependent on latitude.
The first is a daily effect. There are more meteorites in the morning than in the evening, because the morning hemisphere is the part that leads the Earth in its orbit (so, it is 'running into' the meteoroids) and the evening hemisphere is the trailing one. That's why meteor showers are at their best after midnight.
The second is seasonal, due to the fact that meteoroids come from 'streams' of material. The strongest produce distinct meteor showers, but some of the weaker ones all added together mean there's an uneven 'background' of sporadic meteors. This also changes by latitude, since different latitudes would sample different parts of the cloud. However, that's a small effect -- 6000 km (the radius of the Earth) isn't that much.
The third is affected by latitude. At high latitudes, parts of the Earth are always part of the leading or trailing hemisphere, so they always get the benefit of the first effect I mentioned. Think of it as another thing related to the 'midnight sun' effect. During the spring, the high latitudes of the Earth are shielded, like they are during the evening. It's mostly a big deal for places like Alaska (near the pole), and wouldn't be noticeable at all near the equator (like Vietnam).
Also, living in a city (or somewhere else with light pollution) will mean you see less meteors, for the same reason that you see less stars. The more stars you see, the easier it is to see meteors.
In a related matter, Antarctica is a good place to collect meteorites, but not because of the latitude, but because most of the continent's natural rock is buried under the ice, so any rock found is much more likely to have come from above than below.
Get More 'Curious?' with Our New PODCAST:
- Podcast? Subscribe? Tell me about the Ask an Astronomer Podcast
- Subscribe to our Podcast | Listen to our current Episode
- Cool! But I can't now. Send me a quick reminder now for later.
How to ask a question:
If you have a follow-up question concerning the above subject, submit it here. If you have a question about another area of astronomy, find the topic you're interested in from the archive on our site menu, or go here for help.Table 'curious.Referrers' doesn't existTable 'curious.Referrers' doesn't exist
This page has been accessed 8818 times since September 17, 2008.
Last modified: September 17, 2008 2:25:33 PM
Ask an Astronomer is hosted by the Astronomy Department at Cornell University and is produced with PHP and MySQL.
Warning: Your browser is misbehaving! This page might look ugly. (Details)