Did you see the total lunar eclipse last Sunday night/Monday morning? It was quite lovely, as all such eclipses are. But if you did watch, and happened to be looking at the Moon at the right time — around 04:41:43 UTC (11:41:43 p.m. US eastern time), give or take — you may have seen a pretty cool bonus: A small asteroid impacted the Moon, giving off a bright flash! The impact occurred just moments after totality began — the moment when the last bit of Moon slipped into the deeper part of Earth's shadow. A lot of people claim to have noticed it on their own, not sure of what they saw at the time, but as it happens there were quite a few live streams through telescopes at the time, and many of them caught the extremely brief flash. The Griffith Observatory in Los Angeles was doing a live feed using their lovely 30-cm Zeiss refractor, and the flash of light can be seen on the lower left edge of the Moon, very near the limb (I've set the video to start a few seconds before the impact, which occurs at 3:43:11 in the video; it may help to slow the playback speed to 1/2): Video of Total Lunar Eclipse January 20, 2019 Did you catch it? It's fast! Here's a screen capture: Zoom In A small asteroid, probably only a few kilograms in mass, slammed into the Moon during a lunar eclipse on January 20, 2019. Credit: Griffith Observatory Here's another view, this one from the TimeandDate.com's live feed. Again the video is set to start a few seconds before the flash (which happens at 1:20:46), which in this view is more to the upper left of the Moon: Video of January 2019 Total Lunar Eclipse Live Part 2 (Main) Here's a screen capture from that feed: Zoom In The small asteroid that impacted the Moon during the January 20, 2019 lunar eclipse created a flash bright enough to be seen in small telescopes. Credit: TimeandDate.com It was also seen by the MIDAS survey (Moon Impacts Detection and Analysis System), designed specifically to capture impact flashes: Video of Impact on the Moon during the Jan.21 lunar eclipse Incidentally, NASA has been monitoring lunar impacts for quite some time. We've seen lots before, but any new one seen is still important. This is more than just a cool curiosity: If the impact site can be found with high enough accuracy, it's possible the Lunar Reconnaissance Orbiter can get images of it! The brightness of the impact flash seen depends mostly on the mass of the impactor and the velocity at which it was traveling (see below), so if LRO can spot the crater and measure its size, that too can be tied with other physical properties of whatever hit the Moon. These and other videos, plus images taken by people back on Earth, can help nail down the impact site location. Unfortunately, what we've seen so far is only good to a few kilometers accuracy on the impact position, so I'm making a public plea: If you have high-resolution observations taken with a telescope 25 cm or bigger, please contact planetary geologist Justin Cowart: His email is Justin (dot) cowart (at) stonybrook (dot) edu or you can find him on Twitter. Justin has been collecting data on the impact site, and has narrowed the location down to the coordinates 29.47S, 67.77W (+/- 4km): Zoom In The impact site of a small asteroid that hit the Moon during a lunar eclipse is mapped here; the inner ellipse marks the region where the uncertainty is limited by the flash, and the outer by uncertainties in the locations of the observers. Credit: Justin Cowart There's some uncertainty to the exact location due to various effects (like pinpointing the fireball (small gray ellipse in the image above), plus the location of the observers on Earth (larger ellipse)). The uncertainty takes the shape of an ellipse because the impact site is near the limb of the Moon as seen from Earth, and so the landscape is foreshortened there. A small uncertainty in longitude translates into a wider physical area in the east/west direction than north/south. Also as he points out, as LRO orbits the Moon it takes images with a swath about 5 km wide. If his estimates are off by even a small amount, LRO might miss it! Interestingly, I talked to Noah Petro, Project Scientist for LRO, and he noted that the impact may have created secondary craters, smaller ones made by debris blown out by the main impact. Those will spread out over a larger area, and are easier to spot, so it's possible that even with a rough location known beforehand the crater can be found. Also, fresh craters look distinct from older ones — they're brighter, and have a bright fresh splash pattern around them — so once it's in LRO's sights it should be relatively easy to spot. Zoom In Amateur astronomer Christian Fröschlin saw the impact as well; he added together several video frames to make this composite. The streak to the upper left is a star. Credit: Christian Fröschlin It's not clear how big the crater will be. I've seen some estimates that the rock that hit was probably no more than a dozen kilograms or so, and the crater will be probably 10 meters across. That's small, but hopefully its freshness will make it stand out. I'll note that I did a live stream myself during the eclipse, but I was using a small spotting 'scope, and as it happens I was fiddling with the pointing right when the asteroid hit! Otherwise, it's possible it would've shown up in my own video. Ah well. I was having a devil of a time keeping my phonecam focused anyway. Also, a lot of people on Twitter were asking why the impact made a flash when the Moon has no atmosphere. Good question! We see meteors because they burn up in our air, but on the Moon they just slam into the ground. But either way makes a flash. An impactor is typically moving very rapidly, dozens of kilometers per second. That translates into a lot of energy in its motion (called kinetic energy). Think of it this way: If I toss a marshmallow at you it's easy to stop, but a truck rolling toward you at the same speed is far harder! It takes more energy to stop it. For an impactor, the energy of motion is huge, and when it hits the ground that energy is released. Some of it goes into the surface material, ejecting it and forming the crater. Some small fraction of it goes into light and heat as well, making the flash we see. I've seen estimates that only 0.1% goes into light, but even a ten-kilo rock moving at, say 20 km/sec has the energy of a half ton of TNT exploding. I find this whole thing wonderful. While such impacts may be common on the Moon, this one has the potential to be different: Because it happened during a widely observed total lunar eclipse a lot of people saw it for themselves, and we may yet get more and better observations of it from the fleet of telescopes taking video at the time. So if you have good data, let Dr. Cowart know! You can help advance the scientific knowledge we have of our Moon, just because you wanted to see a pretty celestial event. How cool is that?<doc-sep>Community Corner Meteorite Strikes During Super Blood Wolf Moon Eclipse It was rare enough that a lunar eclipse and supermoon coincided, but even more so when a space rock hit the lunar orb during totality. Reply Sunday's lunar eclipse offered something unexpected, even among the seasoned astronomers whose life work is studying the moon — a sudden flash of light as a meteorite hit the edge of the moon just during the eclipse. The lunar eclipse, called a "blood moon" because the orb turns a crimson or copper color when the Earth's shadow falls on the entire moon, was rare enough because it occurred during a supermoon. Space rocks of the same size hit the moon every week or so, Justin Cowart, a Ph.D. candidate at Stony Brook University in New York, told National Geographic. But for that to happen during a lunar eclipse is "a rare alignment of infrequent events," he said, adding this may be the first time a strike has been recorded during a lunar eclipse. Patch delivers Across America. Click here for our free morning national newsletter. Many Scientists were initially skeptical — planetary scientist Sara Mazrouei of the University of Toronto told National Geographic she thought the flicker of light might have been caused by a camera — but a multitude of photos erased their doubt. That delighted eclipse watcher who got an unexpected treat..<doc-sep>
A cherry moon in a cold sky kept skywatchers looking up Sunday (Jan. 20) as the moon passed into Earth's shadow. This "blood moon" eclipse is the last for North America until 2022, so Space.com's Steve Spaleta has compiled a video supercut of the imagery from one of the webcast feeds of the eclipse. Astrophysicist Gianluca Masi ran a livestream from the Virtual Telescope Project during the eclipse, incorporating footage from spots in North and Central America from the project's location in Ceccano, Italy. While the eclipse took place over several hours, the supercut compresses the project's footage to less than a couple of minutes. That's enough time to see the moon go into shadow, turn red and then emerge again. The imagery eclipse team included astrophotographers Joaquin Fabrega Polleri, Panama; Gary Varney, Florida; John W. Johnson, Nebraska; James McCue, New Mexico; and Ron Delvaux, Arizona. [Amazing Photos of the Super Blood Wolf Moon of 2019!] An awesome supercut video from The Virtual Telescope Project by astrophysicist Gianluca Masi in Ceccano, Italy showcases amazing views of the Super Blood Wolf Moon lunar eclipse of Jan. 20, 2019. (Image credit: Gianluca Masi/Virtual Telescope Project) In a description of the eclipse written on the Virtual Telescope website before the event, Masi said the aim was to share with viewers "the stunning beauty of such a unique event." The eclipse, he added, took place during a supermoon — when the moon is at the closest point of its orbit around Earth. It made the eclipse "even more fascinating," he wrote. A blood moon takes place when the moon passes fully into the deepest part of the Earth's shadow during a lunar eclipse. There, the moon only receives red light filtered through the edges of Earth's atmosphere. There are other kinds of possible lunar eclipses, such as a partial eclipse (which happens when the moon goes partially into the deep shadow) and a penumbral eclipse (when the moon passes into the lighter part of Earth's shadow, barely darkening at all). Although there are no total lunar eclipses worldwide until 2021, and none in North America in 2022, there will be a variety of partial and penumbral lunar eclipses to enjoy. You can get more details on how lunar eclipses work at this Space.com article. Follow us on Twitter @Spacedotcom and on Facebook. Original article on Space.com.