Stories tagged meteors

Feb
19
2013

Asteroid: A number of public and private researchers are keeping tabs on the asteroids and other space objects that could hit Earth.
Asteroid: A number of public and private researchers are keeping tabs on the asteroids and other space objects that could hit Earth.Courtesy NASA/JPL
Last week could have been called "Chicken Little Week" with the near miss of Earth by an asteroid and and the dazzling, but havoc-producing meteor crossing through the Russian skies. Have you taken off your safety helmet yet?

While it takes an extraordinary week like that to make most of us think about the dangers looming out in space, there are researchers dedicated to tracking the dangerous projectiles in space. Here's a great report on public and private research groups keeping track of the random traffic in the skies.

Interestingly, they claim that we only really spot about 10 percent of the miscellaneous space stuff that could collide with Earth. And, they're not just settling for trying to pinpoint where the problems are. They're trying to figure out ways to deflect or break-up potentially damaging space threats. Taking it one step higher, some are even investigating ways to mine key minerals from these threats to Earth.

Nov
19
2010

This past week on November 17th, the Leonid Meteor Shower sent meteors streaming down on Earth. "Shooting stars," or meteors, are actually bits of debris in space that burn up upon entering the earth's atmosphere at high speed. Technically, the meteors don't run into the Earth, the Earth runs into the meteors.

The trail of debris in space that the Earth encounters every November 17th was laid down by the comet Tempel-Tuttle. The comet orbits the sun and has made many orbits, laying down a trail of dust and debris on each pass. The comet was first recorded in the year 1366 and has an orbit period of 33 years.

This year was not a spectacular show. The peak, the time when earth passes though the densest part of the trail, only produced about 20 meteors per hour. There have been spectacular years when the Leonids produce meteor storms. These tend to occur every 33 years and there can be thousands of meteors per hour. The next storm probably won't be until around the year 2042.

This year, it was cloudy at my home so I "observed" the shower in a completely different way. I listened to it.

Let me explain.

The US Air Force runs the Space Surveillance Radar in Kickapoo, Texas. There's a lot of junk in space and when the government is flying multimillion dollar craft up there they want to keep them safe. Twenty-four hours a day the space radar puts out 800 kilowatts of continuous wave power at 216.98 Mhz. It sounds like a steady tone on a receiver. The primary mission is to monitor everything in orbit. It can detect objects as small as 10 centimeters orbiting at up to 30,000 km above earth. The radar works by having the signal bounce off objects and reflect the signal back to a number of listening stations.

During a meteor shower, meteors streak through the atmosphere and create a trail of ionized dust. The radio signal reflects off this trail and we can hear the signal of the radar change. Space Weather Radio, a private group, has a listening station set up by Stan Nelson on the roof of his house a couple hundred miles away in Roswell, NM. Space Weather Radio streams the signal over the web and you can listen in. During a meteor shower, you can recognize meteors by the sound.

I recoded for an hour and successfully heard the signature sound of meteors streaking through the atmosphere. For sure a cool experience on an otherwise cloudy night.

More Information
Hear recordings of meteors from the 2010 Leonids
Listen to Space Weather Radio Live

Meteor alert!

by Gene on Jan. 03rd, 2008

The first meteor shower of 2008 is tonight, and it promises to be a good one. (Sorry for the late notice--I thought it was going to be Friday night, but in fact it is early Friday morning.) Peak activity occurs at 1:40 am Eastern Time, but there should be frequent meteors for up to 4 hours before and after. Viewing will be best in western Europe just before dawn, with up to 120 meteors per hour. Eastern North America could see 30 to 60 meteors per hour. In central and western North America, the meteors will be below the horizon until after the peak has passed, but it may still be possible to see up to 30 meteors per hour in the post-peak hours.

As always when meteor hunting, aim to go out a little before midnight local time. Get somewhere far from city lights. Lay out a blanket or lawn chair and look east. Do not use binoculars -- just keep scanning the skies. Bring a thermos of hot chocolate if you can.

Dec
13
2007

Buckle up, Willy: A nice illustration of a mammoth, ruined by a bullseye,
Buckle up, Willy: A nice illustration of a mammoth, ruined by a bullseye,Courtesy rpongsaj
Man, life 35,000 years ago was so much cooler. Sure, they didn’t have the robots and flying cars we enjoy today, in the future, but think about all the great stuff that was around then… There were mile-high ice cubes roaming the northern hemisphere, hilarious cave men, and practically every animal was huge and had “wooly” attached to its name.

Now we can add to that list “earth-sighted extra-terrestrial mega-shotguns.” This is a scientific term, which I have just invented.

An earth-sighted extra-terrestrial mega-shotgun is, in layman’s terms, a meteorite that explodes in Earth’s atmosphere and blasts the surface with tiny fragments of rock. Scientists have just recently revealed details of a study that suggests that ice-age animals were exposed to an earth-sighted extra-terrestrial mega-shotgun at least once, between 35,000 and 13,000 years ago.

The discovery came as scientists at the Lawrence Berkeley National Laboratory were pursuing the theory that there was an atmospheric impact around 13,000 years ago. The researchers had found layers of sediment across North America, dating to 13,000 BP, which contain trace amounts of meteorite material, as well as a black layer that may be charcoal from wildfires caused by such an impact. The team assumed, then, that animals living at this time might also display evidence of the event. By sorting through the collection of a fossil trading company, the scientists quickly found a large handful of fossils that did indeed appear to be blasted by meteorite fragments.

The majority of the fossils were Alaskan mammoth tusks, each peppered with 2 – 3 mm wide holes with all the characteristics of high-velocity projectile impacts. The material inside the holes was magnetic, with a high iron-nickel content, and depleted in titanium (suggesting an extra-terrestrial origin). The group also found a Siberian bison skull that had been blasted by meteorite shards, which showed healing over the impact holes (implying that the animal survived the event). The meteorite shards appear to have exploded inside the tusk and bone. That’s pretty cool too.

The odd thing, however, is that these ESETMS (Earth-Sighted Extra-Terres… whatever) fossils all appear to be much older than 13,000 years, each dating to around 35,000 BP. This could imply multiple ESETMS impacts, although the authors of the report are attempting to tie the fossils and the sediment evidence into a single event. It is possible, they argue, that the mammoth tusks could have been blasted long after then animals’ deaths, while emerging from permafrost or exposed on a riverbank. This doesn’t account for the healing of the bison skull (unless it dates from a different period than the tusks), nor does it resolve the wide geographical separation of fossils (Alaska and Siberia are close, but not that close). The article doesn’t bring it up, but I wonder if animal migration might explain the distance between the fossils, especially if the mammoths were killed by the meteorites either (their tusks wouldn’t have healed either way, after all).

Aside from what spectacular fun the mega space shotgun would have been, the theory is interesting in that, depending on the date or dates of the events, it may have played a role in the extinction of ice age mega fauna. The cause of the Pleistocene extinctions (which wiped out mammoths, mastodons, giant sloth, etc) has long been under debate – some argue that climate change was the culprit, some believe that increasingly skilled human hunters were responsible, and others think that a combination of the two is most likely. While these meteorite impacts probably wouldn’t have caused the extinction on their own, as one scientist put it, “You can't imagine it helped the animals having a large meteorite hit the Earth's atmosphere and pellet them with shot.”

Help them survive, no. Help them be even more awesome? Yes.

Dec
10
2007

A meteor streaking across the night sky: The Geminid meteor shower peaks this week on the night of December 13-14.  Photo by Jeff Smallwood at flickr.com.
A meteor streaking across the night sky: The Geminid meteor shower peaks this week on the night of December 13-14. Photo by Jeff Smallwood at flickr.com.

The last big meteor shower of 2007 will hit this week, and it's expected to be a doozy! The 2007 Geminid meteor shower peaks on the night of December 13, though meteors may be visible any night this week. What's more, it's supposed to be the best shower of the year! (And I can attest from personal experience that most of the previous showers this year have been a disappointment.)

If you want to catch the show, here's what you do:

  • Head out before 10 pm local time.
  • Bring a lawn chair or sleeping bag.
  • Dress warmly. A thermos of hot chocolate is optional, but highly recommended.
  • Get away from city lights.
  • Set up chair or sleeping bag, and sit / lie down.
  • Look up.

That should do it. The shower will increase as the night goes on, reaching rates of about one meteor per minute by dawn. (Folks who don't want to pull an all-nighter are advised to go out after midnight.)

The meteors will appear to be coming out of the constellation Gemini, about half-way up the sky in the east. But they will be streaking all across the heavens, so you don't really need to be facing in any particular direction.

No special equipment is needed. Meteors are visible to the naked eye. In fact, using a telescope or binoculars will actually hurt your chances of seeing a meteor, as they focus your attention on a small area. You want to keep scanning the entire sky.

For more information on the Geminid meteors, go here.

For tips on meteor watching, go here.

And, as a special treat, both Jupiter and Saturn should be visible that night as well.

Aug
28
2007

Anybody see the eclipse last night? It looked something like this.

Looking ahead, Charles Deehr of the University of Alaska sends word of a great meteor shower coming on the night of August 31 / September 1. Unfortunately, by the time it hits, the eastern and Midwestern US will already be in daylight. This shower will only be visible on the West Coast, Hawaii and similar places. It's expected to start around 4:00 am PDT, plus or minus 20 minutes, so Californians need to get out there around 3:30 and look east.

He also tells us we may see some aurora activity around the equinox (September 22). The Sun is not particularly active this year, so it won't be a spectacular display -- though he expects next year to start getting better. Anyway, readers in Canada, Alaska, Scandinavia, and the very northern US (northern Minnesota, the UP, places like that) might get lucky and see some.

May
03
2007

A meteor streaking across the night sky: Photo by Jeff Smallwood at flickr.com.
A meteor streaking across the night sky: Photo by Jeff Smallwood at flickr.com.

The Aquarid meteor shower is due to reach its peak this weekend. Clear skies and warm spring temperatures in many parts of the country will make this the first good meteor viewing of the year. The shower is due to peak at 7 am Eastern time on the 5th with meteors falling at a rate of about one per minute. But you can go out any night this weekend after midnight and look low in the eastern sky – you may catch a few falling stars to put in your pocket and save for a rainy day.

You can learn more about meteor showers here.

This site has more kid-friendly information.

And this is a good site for heavy-duty meteor fans.

I love Earth & Sky radio's skywatching center. It always features tonight's sky chart and weather, plus skywatching tips and any news. Find out when the moon will rise, what phase of the moon we're in, and where visible planets will be in the sky and when you should look. Plus, it's packed with links to other resources, like interviews with scientists and web planetariums. And you can blog! Check it out...

Aug
04
2005

An impressive display of meteors will move across the sky on Friday, August 12, (2005) when the Perseid meteor shower becomes most visible. Peak viewing times will be from 2 a.m. until sunrise that morning, according to NASA experts. Because of interference from urban lights, viewing is best outside of the city. The Perseid meteor shower occurs every summer, when the tail behind Comet Swift-Tuttle intersects with Earth's orbit, causing comet dust to enter Earth's atmosphere. Meteors from the comet travel from the direction of the constellation Perseus, which gives the shower its name.