{"id":259017,"date":"2010-02-01T09:00:30","date_gmt":"2010-02-01T14:00:30","guid":{"rendered":"http:\/\/blogs.discovermagazine.com\/badastronomy\/?p=10984"},"modified":"2010-02-01T09:00:30","modified_gmt":"2010-02-01T14:00:30","slug":"terra-spots-an-impact-on-um-terra-bad-astronomy","status":"publish","type":"post","link":"https:\/\/mereja.media\/index\/259017","title":{"rendered":"Terra spots an impact on, um, Terra | Bad Astronomy"},"content":{"rendered":"

While high over the grasslands of Kazakhstan, the Terra Earth-observing satellite saw something interesting<\/a>… can you spot it in this image?<\/p>\n

\"terra_chiyli_lrg\"<\/a><\/center>
<\/p>\n

Not so easy, is it? But if you look just left of center you’ll see this:<\/p>\n

\"terra_chiyli\"<\/center>
<\/p>\n

See it there, right in the center? It’s the Chiyli impact crater, an ancient scar from a cosmic collision. The crater is roughly 1.5 km across (about a mile) — about the same size as Meteor Crater in Arizona — meaning the object that created it was something smaller than a football field, moving at perhaps 30 km\/sec (20 miles\/sec). It hit about 46 million years ago, give or take. Long after the dinosaurs, but long before us, too<\/a>. Note that it’s a double-rimmed crater too, which sometimes form in large impacts depending on the conditions of the impactor and the ground.<\/p>\n

This is a false-color image, at least part of which is in the infrared; vegetation appears red, water blue, and bare land is “earth tones” (browns and tans). This sort of imagery allows scientists to investigate how vegetation, land, and water change over time. <\/p>\n

\"terra_chiyli_flipped\"When I first saw this image, I didn’t see it as a crater, but more as a raised annulus, a ring in the ground. I knew immediately that this meant that in the picture, the sunlight was coming up from the bottom, and it turns out that’s correct. It’s a cool and optical illusion; when we see craters illuminated from below, they look like domes, and vice-versa<\/a>. In the picture here, I flipped the image and now, to me at least, it looks more like the depression that it really is. The wide inner rim is more obvious, too.<\/p>\n


<\/p>\n

Here’s an even better example:<\/p>\n

<\/p>\n\n\n\n
<\/td>\n<\/td>\n
Is it a dome…<\/td>\n… or a crater?<\/td>\n<\/tr>\n<\/table>\n

<\/center>
<\/p>\n

It just goes to show you that finding evidence of extra-terrestrial events on Earth can be tough, and even when you find them you can’t rest easy. They’re apt to fool you one way or another.<\/p>\n

<\/a>
\n<\/a><\/p>\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

While high over the grasslands of Kazakhstan, the Terra Earth-observing satellite saw something interesting… can you spot it in this image? Not so easy, is it? But if you look just left of center you’ll see this: See it there, right in the center? It’s the Chiyli impact crater, an ancient scar from a cosmic […]<\/p>\n","protected":false},"author":641,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":["post-259017","post","type-post","status-publish","format-standard","hentry","category-news"],"_links":{"self":[{"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/posts\/259017","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/users\/641"}],"replies":[{"embeddable":true,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/comments?post=259017"}],"version-history":[{"count":0,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/posts\/259017\/revisions"}],"wp:attachment":[{"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/media?parent=259017"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/categories?post=259017"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mereja.media\/index\/wp-json\/wp\/v2\/tags?post=259017"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}