In the Sahara, a team of scientists claim to have found the first evidence of a comet directly impacting Earth.
About 28 million years ago a comet exploded over Egypt, creating a 3600°F (2000°C) blast wave that spread out over the desert below. The fiery shockwave melted the sand, forming copious amounts of yellow silica glass scattered over 2,300 square miles (6,000 square kilometers) of the Sahara.
Polished into the shape of a scarab beetle, a large piece of this glass found its way into a brooch owned by the famed Egyptian boy king Tutankhamen.
Read the rest of my comet story at National Geographic News.
Tags: astronomy, comet, impact, science, space, Tutankhamen
Posted in Meteors, Planets, Solar System | Comments Off
Earlier this year in February the world had a wake-up call when a giant 17 ton rock from space entered the atmosphere in Siberia and created a giant air-blast that literally was felt around the world.
A new study was released this week that analyzed this meteor impact and the results show that when the hypersonic meteor imploded in the upper atmosphere, it created a shockwave that propagated across the globe – not once but twice.
Find out how this big blast ranks in terms of meteor encounters in recent history and how often such cosmic events may occur, in my story for National Geographic News.
Tags: asteroid, impact, science, space
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Mars may have a really bad day next year on October 19th. That’s when there is a very slight chance a newly discovered comet may impact our neighboring planet, says NASA.
Comet C/2013 A1 (Siding Spring) was discovered by Australian Robert H. McNaught, a prolific comet and asteroid hunter just two months ago and NASA’s Near-Earth Object Program Office at the Jet Propulsion Laboratory , in Pasadena, Calif., has been constantly refining the comet’s exact trajectory ever since.
Read the rest of my Mars comet story at National Geographic News
Tags: comet, impact, Mars
Posted in Planets, Solar System | 1 Comment »
After last week’s NASA public relations fizzle, when their lunar probe didn’t appear to produce any visible signs of a much touted plume rising into space, it seems they have been partially vindicated.
According to the agency’s news announcement on Friday, the trailing LCROSS probe did in fact snap photos of the resulting impact explosion by its booster rocket when it hit the moon.
The crash created a crater about one-fifth the size of a football field inside the shadowy bottom of a 98 km wide crater near the south pole last week. Mission scientists are not yet ready to say what the plume was made of but space buffs are hoping that it was filled with water.
Read more on the incoming results on LCROSS mission’s website.
Editor’s note: Take a peek at my latest Weather Network – Night Sky show video on the left-side bar or on the Videos page. Also check out the new scrolling Sky Calendar on the left-sidebar that gives a brief heads-up on the major astronomical events for the coming weeks. With plenty of notice, never miss another big sky event again!
Tags: impact, LCROSS
Posted in Solar System, Space Exploration, The Moon | 39 Comments »
Amateur and professional stargazers are anxiously awaiting this Friday morning’s kamikaze dive of two NASA rockets, part of the LCROSS mission, on the surface of the Moon. The hope is that the resulting impact in a 98 km wide crater near the south pole will create a visible water-rich debris cloud that will rise more than 10 km into space. The thinking by scientists is that there may be a large reservoir of water-ice sitting at the bottom of a deep, internally shadowed, crater called Cabeus. By punching a hole into that crater floor, it would kick up a bunch of that ice out into space for lunar orbiters to analyze. About 10 hours before the lunar smash up the LCROSS probe will separate from its 12 meter long Centaur booster rocket. This 2200 kg booster will be the first to impact and may throw up over 300 tonnes of lunar dust. The 700 kg probe will be right behind the rocket so it will be getting an up close and personal view of the impact- sending back, sure to be, amazing snapshots, before it too smashes into the moon 4 minutes later at 7:34 am EDT.
The hope also is that the impact and plume might be visible with telescopes here on Earth and in orbit. A fleet of professional observatories will be trained on the impact site on Friday morning at 4:30 am Pacific time/ 7:30 am Eastern Time for the first impact, but so will backyard astronomers with their telescopes. There is a real chance that stargazers with medium sized scopes, about 10 to 12 inches, may be able to witness first hand the explosion on the Moon, and the resulting expanding, ring-like plume that will rise up. Best chances to see this event will be for observers located west of Manitoba and west of the Mississippi River and the Pacific Ocean region. Unfortunately folks on the eastern side of the continent will have daybreak blinding them. If you are lucky enough to have the right instruments and are in the right location then you can be part of the mission and help scientists analyze this event by contributing your valuable observations.
Here is a great viewer’s guide called ‘Citizen Science – a Public Observing Campaign’ prepared by NASA on how you can contribute to the science behind this unique and exciting event. Also check out a detailed information guide (PDF file) to the timing and location of the impact.
But don’t fret if you are not able to watch the impact through a telescope yourself, because there will be LIVE broadcast of the event put on by NASA and observatories showing the latest video and photos beamed back from telescopes on the ground and in space. There will even be cameras aboard lunar orbiters only a few hundred km above the Moon that should have ring-side seats to the show. Stay tuned to my blog for the LIVE broadcast video. So mark down Friday 7:30 am EDT/4:30 am PDT on your calendars and stay tuned…
Tags: impact, LCROSS
Posted in Solar System, Space Exploration, The Moon | 17 Comments »
With Jupiter just being smacked again by a potential comet or asteroid, the media are abuzz once more with the discussion of our own planet being in danger from a doomsday rock from space. What exactly are the risks? Space.com ran an interesting story today where astronomer Donald Yeomans, manager of NASA’s Near-Earth Object program office at the Jet Propulsion Laboratory, was asked how well we were doing in tracking down wayward asteroids that may have Earth in their cross-hairs. Turns out that its the highrise-sized boulders, not the giant, city-sized dino-killers that we need to possibly watch out for in the short-term, ie. in our lifetime.
“Researchers suspect about 156 large NEOs 1 kilometer in diameter or larger remain to be found, and when it comes to dangerous NEOs in general, “when we get down to 140 meters (460 feet) or larger diameter objects, we think we’ve discovered about 15 percent of them, and with 50 meters (164 feet) or larger diameter, we’ve discovered less than 5 percent of them,” Yeomans explained.
On average, an NEO roughly a half-mile wide or larger hits the Earth roughly every 500,000 years, “so we’re not expecting one anytime soon,” Yeomans explained.
“For 500 meters (1,640 feet), we’re talking a mean interval of about 100,000 years,” he added. “When you get down to 50 meters, the mean interval is about 700 years, and for 30 meters (98 feet), about 140 years or so, but by then you’re getting down to a size where you won’t expect any ground damage, as they burn up in the atmosphere at about 25 meters (82 feet) in diameter and smaller, probably for an impressive fireball event.”"
I am not sure that all of them would burn up in the atmosphere at those sizes however. There have recently been much talk in the science community that even air bursts of building sized rocks, if they are solid enough can produce extensive local damage. There is still way too much speculation going on without any definite answers as to what the real dangers are. Hopefully cosmic impact events like this past week and the resulting chatter will result in more vigorous research into this field. After all, our life may depend on it.
Tags: asteroid, impact, NEO
Posted in Meteors, Solar System | 378 Comments »
Check out this amazing hi-rez photo taken by the revamped Hubble of the recent impact on the king of all planets. Even though the space scope is still undergoing testing, scientists decided that this impact was too big of a science event to miss out on so they decided to turn Hubble on Jupiter. What a sight!
Tags: impact, Jupiter
Posted in Planets, Solar System | 2 Comments »
It was 15 years ago today that comet Shoemaker-Levy 9 made history when it began a series of impacts with the giant planet Jupiter. over 20 separate chunks of the comet spread out in space individually collided with Jupiter over a period of a week. it was the first time in human history we saw a comet collide with a planet. Many of today’s accomplished backyard astronomers can trace their own beginnings in the hobby to watching this momentous, celestial event.
Tags: comet, impact, Jupiter, Shoemaker-Levy 9
Posted in Planets, Solar System | 90 Comments »