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How to Discover Impact Craters with Google Earth
Maikel_NAI writes "Believe it or not, Emilio Gonzalez, a Spaniard amateur began his crater search at home after reading an article about the discovery of Kebira, the biggest one found in the Sahara. After a couple of minutes he located two craters. After checking the records, he realized these were completely new, and now two geologists confirm his findings. And there is more, these craters may be part of a chain studied by NASA geologist Adriana Ocampo, so if it's confirmed that these new ones are part of the same episode, it could mean the definitive evidence for her theory of an asteroid broken into pieces fallen in that area."
Only certain regions are actually photographed well enough for you to see anything decent. One thing i really hope they improve on.
Let's see, we've had archeological sites found by google earth, asteroid impacts found by google earth... who knows what's next?
I love this! You free up information, allow the unwashed masses access to it, and people find hidden treasure. Think how much we'd never know if all this was DRMed, locked and restricted!
Google, don't ever change.
You can't take the sky from me...
The idea that amateurs don't (or can't) do good science or make important discoveries is a more recent addition to popular culture - and it's wrong.
Admittedly, there are fields where it's true - like particle physics, stem cell research, or transplant biology, since the "entry level" for equipment and training is something you're not going to be able to pick up on the cheap (unless you're Bill G).
That said, there are many fields where 'amateurs' not only make important discoveries, they're actually the predominant workers in those fields. Comet discoveries and near-earth astronomy, paleontology, archaeology, and geology among others all have large numbers of amateurs - even outnumbering the "professionals".
What's interesting and exciting about this is that it's given a new set of tools for everyone who's interested to use.
Worldwind is a great companion app to Google Earth. I find its interface more intuitive when looking for visuals instead of just using text searches, and having a choice of imagery is a big bonus.
Google Earth's eye for aerial detail is great, but Worldwind is definitely not to be overlooked.
Try checking the menu on the left and activating the Google community tabs, especially "military." Enthusiasts point out things like military bases, notable vehicles or facilities and, yes, nuclear test sites.
Zoom in on the coastline of southern Cuba and you'll see a narrow bay cutting deeply into the shore. With a little imagination you can almost see the IVth, Vth and VIth ammendments of the Constitution of the United States of America being violated.
I don't know if these sorts of out-of-date images of military installations have any practical value, but they do give a certain valuable sense of reality regarding the existence of places that many people would like us to ignore, or forget. It's hard to think of the prison camp where innocent people are being incarcerated without trial[*] as being "out of sight, out of mind" when you can fire up Google Earth and see it plain as day.
[*] Do the math: there are 500+ people there, mostly captured in battlefield conditions in villages and farms. We know the cops, in the best of circumstances, sometimes get the wrong guy. We know the courts, in even better circumstances, sometimes convict the wrong person. So we no with what would be ordinarily called certainty that a non-trivial number of innocent people are being held, indefinitely, without trial, without legal recourse. Even with the most generous assumptions the number comes out to 25 or so. The only question is: are the goals being pursued so valuable and the means being used to pursue them so valuable as to justify the certain incarceration of innocents? "Is life so dear, and peace so sweet..?"
Blasphemy is a human right. Blasphemophobia kills.
I've been addicted to Google Earth ever since I came across it. Generally, I'm very skeptical about the use of computers in the classroom environment, I think they are help and hindrance in pretty much equal measure - but there should be a computer running Google Earth in every classroom. It's a fantastic tool for teaching geography and geology, and would even help with biology, history and politics.
"Be nice, veer left, and never stop thinking" Iain Banks - Walking On Glass
Yes, there are lots of circular structures in that part of Africa, but whether or not they represent impact structures can not be easily determined without referring to a geological map or doing some ground study. However, there are clues that these particular ones are not impact structrures.
For one thing, notice that the example at 22 06 53 N, 17 55 15 Ehas a circular "mate" just to the south, at 22 deg 04' 24" N. The northern one appears to have an outer ring and an inner raised zone -- suggestive of a complex crater. The southern one, though, just looks like a raised blob, which is not typical. Both have a similar "pinkish brown" colour compared to the surrounding, slightly darker and greener outcrops to the east (the really light zones are desert sand, rather than bedrock, and aren't relevant except as an indication of the topography -- they are lower). The southern of these two looks an awful lot like an ordinary granitic or other igneous intrusion. Its similarity to the ringed one that you mentioned makes me suspicious that they are both the same type of feature.
There are also a bunch of definite volcanoes in the area (it is in Chad), such as at: 21 deg 02' 51" N 17 deg 39' 58" E
21 deg 02' 48" 16 deg 30' 22" E. The former is fairly eroded, the latter is pretty recent -- it has dark-coloured lava flows visible around it. The caldera slightly to the SE has a saline lake in it (produces the blue colour).
There are a few more detailed explanations at NASA's "Earth from Space" website of astronaut photography. Though the explanations are only for a few scattered locations over a vast area, they are a great baseline for attempting interpretations elsewhere in the world as you explore things with Google Earth or similar tools. I highly recommend it.
I suspect alot of the circular structures seen in this area are just volcanic centers in various stages of erosive degradation or even exposure of the former magma chambers beneath them.
To figure it out for sure would still take fieldwork, but what information is known (e.g., take a look at those "Earth from Space" examples) makes me pretty skeptical they are impacts. But don't let that opinion discourage you from looking and asking questions.
Thank you, Google for bringing the fun of geology to everyone!