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March 4, 2011 | 18
Impact craters are usually round, but the European Space Agency's Mars Express orbiter recently sent back this image of a long, oval crater pocking the Red Planet's southern hemisphere. What happened here?
ESA scientists think a series of impacts created this unusual shape. First, two projectiles—or possibly two halves of one projectile that broke in transit—plowed into this spot at a shallow angle, creating the crater. Deeper areas inside the crater suggest even more projectiles hit afterward.
Spread out in wings around the crater is the "ejecta blanket," which was formed from the material that the projectiles threw aside when they hit. The blanket includes several small channels. Scientists think these features may be evidence that this area of Mars was once covered with material—possibly water—that would have melted or boiled when exposed to the heat from the impacts and then flowed, carving the channels.
–Francie Diep
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18 Comments
Add CommentThough I am not a UFOoligist, this photo portrays what one might expect to see from the crash of a large space craft. :)
Reply | Report Abuse | Link to thisThe other explanation and one that seems more likely is that the asteroid struck at a nearly transverse angle and dug out a wider crater at the initial impact point, thence scooping a progressively narrower path as it passed along the surface. Why doesn't this seem more plausible than supposing such a "clean" crater was gouged by multiple objects?
Reply | Report Abuse | Link to thisESA quote: " ..it could have been carved out by a train of projectiles striking the planet at a shallow angle.." How unusual for craters to be caused this way! Normally craters are ONLY formed be EXACTLY PERPENDICULAR IMPACTS and we all KNOW THAT. Or do we?
Reply | Report Abuse | Link to thisFolks, we have been brainwashed since the 60s when the prefix 'impact-' began to take over. Every single crater is now assumed to be an impact. But no proof has been given for this idea. Perfect circles, with flattened bottoms, smooth sides and often central peaks cannot be reproduced by mechanical impact from any approach angle.
If you look carefully at the overall view of Huygens:http://esamultimedia.esa.int/images/marsexpress/109-280904-0532-6-ctxt-01-HuygensRim_H.jpg you will see the context of this oval crater. Ask yourself HOW so many craters here are coincident; many aligned on top of each other. Huygens iteslf looks like two circles in one, surrounded by dozens of daughter and sub-daughter craters. Notice also how many odd-bods exist with central peaks.
Either this a gravity hotspot or some very unusual activity took place near here. Don't forget that Mars is a rotating planet so statistically we should not see such clustering of pockmarks. Craters are supposed to indicate the age of planets, but these look incredibly fresh and similar.
I'm tempted to suggest that the majority of these shapes have been caused by something other than mechanical impact. What could cut such perfect circles? Ask an metallurgy engineer what he would use. You will probably hear the words 'Electric Discharge Machining'. It's a common method using very high voltage guns. Extremely consistent and clean. You can even do the central peak thing if you want.
So these pair of ovals are either the only impacts that really happened or more electrical craters like we see on every body in space.
I agree with ACTORwriter. My first impression (pun intented) is there was one meteor or asteroid responsible for the crater. The average PhD is trained to discount the first or obvious answer as the wrong conculsion. In other words the simpliest solution can never be right. Besides there is grant money in making everything complex.
Reply | Report Abuse | Link to thisThanks for that insight JOSEPH2237, it probably explains why science is in such a s*it state this century. We've been bequeathed an introverted, finance seeking, arrogant academic system that has forgotten the simple objectivity that got us through the early part of the 20th century. When black holes, big bangs, dark matter, dark energy and 'impact' craters make sense, you know that we're on the downward slope.
Reply | Report Abuse | Link to thisHey ho, let's see how long they can keep us kidded.
That is why we need to start calling scientists on the government payroll "Grantologists", since keeping grants seems to be a priority for some.
Reply | Report Abuse | Link to thisLarge object at transverse angle sounds like a reasonable hypothesis.
Reply | Report Abuse | Link to thisRemember "lex parsimoniae?" (Achem's Razor). Transverse impact is the most reasonable.
Reply | Report Abuse | Link to thisHow far have we come in the exploration of the universe? How much do we really know about it? Up till now mankind has succeeded in setting foot on the Moon. This one time project is long ago by now, so long that we only have black-and-white images of it http://ancientvisitors.blogspot.com
Reply | Report Abuse | Link to thisGreetings: At first glance, I thought this to be Orcus Patera, a 360 km long x 140km wide gash on Mars. Looks similar, but this does seem to be a different crater. Research has shown that 5% of impacts are shallow enough to produce oval craters, although Cigarshaped charmingly joked that many scientists demand that all craters are round. Near-tangential impacts create entirely different scenarios for ejecta distribution (butterfly) and impact temperatures & pressures, as they are shearing events vs compressional.
Reply | Report Abuse | Link to thisAnother recently discussed oblique impact on Mars is seen on the Planetary Society Blog (http://www.planetary.org/blog/article/00002894/)
http://www.nasa.gov/mission_pages/apollo/index.html
Reply | Report Abuse | Link to thisYou probably remember the photos as black and white because of the mostly gray lunar surface. They used color film in Hasselblad cameras.
That doesn't look like multiple hits! That looks like a glancing blow to me..!
Reply | Report Abuse | Link to thisIt does make sense that if most craters were formed by impacts they would mostly be of the elongated types since at this point in time most space rocks are traveling at extremely high rates of speed, however, four billion years ago there were many more space rocks and many of them were mostly formed from the accumulation of stardust which basically caused them to form motionlessly with respect to their surrounding bodies. This in turn caused most collisions to be perpendicular to the surface of the larger object they were attracted to. It wasn't until after the population of these objects were minimized and set into motion by secondary collisions that the present day space rocks have so much kinetic energy.
Reply | Report Abuse | Link to thisThe Solar Age is revealing to us how little we know of the reality around us, and how much we have assumed we know; we find that we know very little. One talks of the Scientific methods of investigation when it comes to certain unknowns, and the photo of the enlongated crater is at the top of the heap. Was this crater, in the Southern Hemisphere, created from a single impact or was it created by multiple impacts creating multiple craters? We can speculate whether it was natural or alien-humanoid made; although most discreate the notion of non-humanoids? A reader states that no sturcture can make such an impact creater due to its size and angle of attack. We do not have the expertise to create such mega-structures and will not for at least the next hundred years; closer to the year 2200. Could a person in the 1800 concieve of a skyscraper? We marvel at the space shuttle and the ISS, but we are just begining to learn how to make structures and materials that can withstand the rigors of inner-planetary space; not even thinking of space out of the solar system. Are we any different than that person of the nineteenth century dreaming of skyscrapers. So! The only way to settle the issue of what caused the inpact creater is to go there and find out for ourselves.
Reply | Report Abuse | Link to thisThe facts mam. Just the facts.
hate to break it to ya mate, but your just wrong on this one. Look at the crater, it is far from perfect. If you consider the mechanics of any impact think of it this way. Newtons third law states that for every action, there is an equal and opposite reaction. That is still a pretty solid law today.
Reply | Report Abuse | Link to thisBearing in mind this law, when an object, say an asteroid, smacks into the side of another object, say a planet; it imparts force in the form of kinetic energy. Well then the planet should respond in kind, but as the mass of the asteroid is a fraction of the mass of the planet, the asteroid shatters. When this happens there is still kinetic energy moving the asteroid (or pieces thereof) forward. This starts a chain of smaller reactions like the original. Each piece, however, spreads outwards as this reaction occurs (this is the source of the crater, redirected chunks of rock imparting kinetic energy into the face of the planet.
Naturally as mars is not ony rotating but revolving, few enough asteroids are going to hit it head on (the ration of planet to space is far to negligible to make this likely) thus when any asteroid happens to smack into the planet, it is unlikely to be head on at all.
Putting these two facts together, we now have a reason for the elongated crater. Why so long however? At this point it would be more theory than fact but when an asteroid shatters into fragments, they will stay somewhat together if their are large enough fragments to emit a gravity field of their own and draw the smaller bit with them. In this case it seems likely that one larger fragment pulled along numerous smaller fragments with its gravity and this cluster passed by mars close enough to be sucked into the gravity well of he planet. Due to the spinning motion of the planet and the revolution of it as well it would have pulled the cluster in a decaying circular orbit until the collision occured and the aforementioned reaction occured. The larger fragment would have caused most of the impact and the smaller fragments would have peppered around the main impact creating the gash that we see here.
To sum up, asteroid collision breaks off a cluster of fragments on course that takes them near mars, fragments stay together due to the gravity field of the larger one, cluster gets sucked into a decaying orbit, cluster smacks and spreads as must happen according to newtons third law, strange crater is formed that sparks excited debate amongst net surfers who theorize and hypothesize.
Some scale on the image would be nice.
Reply | Report Abuse | Link to thisI've made very similar craters in the dirt by use of a simple slingshot. That tends to add credence to the single object, glancing impact theory. As for the opinions of the foil hat crowd - very funny but not particularly likely.
Reply | Report Abuse | Link to thisThe idea of a train of impacts certainly sounds more plausible than that of an impact of a train. :)
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