Explosion on the Moon!

Pock-marked with craters and splotched with long-cold beds of dark lava, our moon holds thousands of footprints from its violent past. But we don’t really think of it having a violent present.

Well, it still gets its fair share of action. On March 17, 2013, NASA astronomers captured video of a meteorite striking the moon. It made an explosion bright enough to be seen with the naked eye, like a temporary star drawn on the lunar surface. It turns out that these collisions are not that rare.

Most of the moon’s many meteor marks date from a period known as the Late Heavy Bombardment. That, combined with a magma-riffic adolescence gave the moon the special look we know today. Of course, none of that is as violent as the moon’s birth.

Anyway, make sure to watch that video above and see the meteor strike live. You’ll never look at the moon the same way again.

explore-blog:

Remarkable animated visualization of every meteorite since 861 AD from The Guardian.

(ᔥ Open Culture)

This is awesome! It really hits “death from the skies” level near the end. Which, coincidentally, is the name of a book by Bad Astronomer Phil Plait all about the science behind the ways the world might end (and the ways that it most certainly won’t … like Planet X)

There’s no reason to think that we really have more meteorites hitting Earth these days, like you see in the viz. We just happen to be better at writing things down/not attributing them to sky demons.

Eta Aquarid meteors over New Zealand this week, photographed by Stephen Voss over the course of 90 minutes. Every spring, Earth crosses the orbital trail of Halley’s Comet. While we’ll have to wait until 2061 to see the actual comet again (I am old enough to remember seeing it back in 1986, though, so nah!), each year we get a fresh sprinkling of comet tail dust into our atmosphere at 150,000 mph. As Earth whips through, the debris appears to radiate out from the constellation Aquarius, which is evident in the photo above. It’s a coincidence, but a beautiful one. Read more about the Eta Aquarids at EarthSky and Bad Astronomy.
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Eta Aquarid meteors over New Zealand this week, photographed by Stephen Voss over the course of 90 minutes.

Every spring, Earth crosses the orbital trail of Halley’s Comet. While we’ll have to wait until 2061 to see the actual comet again (I am old enough to remember seeing it back in 1986, though, so nah!), each year we get a fresh sprinkling of comet tail dust into our atmosphere at 150,000 mph. As Earth whips through, the debris appears to radiate out from the constellation Aquarius, which is evident in the photo above.

It’s a coincidence, but a beautiful one. Read more about the Eta Aquarids at EarthSky and Bad Astronomy.

See an Asteroid, Capture a Meteor! It’s been said by many that “luck is what happens when preparation meets opportunity”. Australian photographer Colin Legg has proven that true. He set out to capture last Friday’s fly-by from asteroid 2012 DA14 and accidentally caught with a burning meteor entry. Think about it! You set up your camera to capture something well-planned and expected, and out of nowhere you see a burning fireball rush through your field of view, complete with its wispy vapor trail. Too cool. In the full high-definition video (which you should really check out), you can also see a number of other man-made satellites moving through the frame. Altogether, one of the coolest space sequences I’ve seen in a long time. (via EarthSky)
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See an Asteroid, Capture a Meteor!

It’s been said by many that “luck is what happens when preparation meets opportunity”. Australian photographer Colin Legg has proven that true. He set out to capture last Friday’s fly-by from asteroid 2012 DA14 and accidentally caught with a burning meteor entry.

Think about it! You set up your camera to capture something well-planned and expected, and out of nowhere you see a burning fireball rush through your field of view, complete with its wispy vapor trail. Too cool.

In the full high-definition video (which you should really check out), you can also see a number of other man-made satellites moving through the frame. Altogether, one of the coolest space sequences I’ve seen in a long time.

(via EarthSky)

Chelya-boom-boom A meteor burned up above the skies of central Russia this morning, resulting in an aerial explosion and shockwave whose effects injured hundreds near Chelyabinsk. It brings to mind these lines from Samuel Taylor Coleridge’s The Rime of the Ancient Mariner: The upper air burst into life!And a hundred fire-flags sheenTo and fro they were hurried about!And to and fro, and in and out,The wan stars danced between Events like this are not rare in Earth’s atmosphere, happening at least once per decade. What made this one special was its chance occurrence over a populated area and the fact that so many Russians have cameras running on their dashboards, like, all the time. Central Russia is no stranger to extreme aerial explosions due to space debris entering the atmosphere, most famously with 1908’s Tunguska Event, a several megaton aerial explosion of a comet fragment that knocked down 80 million trees. Details about today’s meteor event are a little fuzzy, but I plugged some data into Purdue’s Impact Earth! meteor event calculator (which is a super fun way to pretend you’re destroying Earth) to see if I could nail down the energy released by this fireball. From the videos I’ve seen, it looks like this thing entered the atmosphere at a pretty shallow angle, maybe 15 degrees from the horizon. It would have to be pretty dense rock in order to make it that far into the atmosphere without disintegrating, so I plugged its density in as 3,000-5,000 kg/m3. Russian officials reported its aerial velocity at about 15 km/second and that it was about the size of a dinner table, so 4 meters across? If you tweak the velocity, density, size and angle a little, you get an airburst of between 2 and 5 kilotons of TNT, or a little less than half the strength of the atomic bomb that exploded over Hiroshima, and an explosion altitude upwards of 50,000 feet. Seems like a pretty accurate calculation, although the actual altitude must have been more like 30,000 feet to produce the shockwave that resulted in all the injuries. Play around with the Impact Earth calculator and let me know if you get anything better! Although asteroid 2013 DA14 is making a close flight by Earth today, zipping inside of some of our satellites, but this meteor event almost certainly had nothing to do with that. Space is full of stuff, and every so often we are reminded of that in spectacular fashion. BONUS: This kind of thing happens all over the solar system. Check out this scorched explosion remnant on Mars! (GIF via amalucky)
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Chelya-boom-boom

A meteor burned up above the skies of central Russia this morning, resulting in an aerial explosion and shockwave whose effects injured hundreds near Chelyabinsk. It brings to mind these lines from Samuel Taylor Coleridge’s The Rime of the Ancient Mariner:

The upper air burst into life!
And a hundred fire-flags sheen
To and fro they were hurried about!
And to and fro, and in and out,
The wan stars danced between

Events like this are not rare in Earth’s atmosphere, happening at least once per decade. What made this one special was its chance occurrence over a populated area and the fact that so many Russians have cameras running on their dashboards, like, all the time. Central Russia is no stranger to extreme aerial explosions due to space debris entering the atmosphere, most famously with 1908’s Tunguska Event, a several megaton aerial explosion of a comet fragment that knocked down 80 million trees.

Details about today’s meteor event are a little fuzzy, but I plugged some data into Purdue’s Impact Earth! meteor event calculator (which is a super fun way to pretend you’re destroying Earth) to see if I could nail down the energy released by this fireball.

From the videos I’ve seen, it looks like this thing entered the atmosphere at a pretty shallow angle, maybe 15 degrees from the horizon. It would have to be pretty dense rock in order to make it that far into the atmosphere without disintegrating, so I plugged its density in as 3,000-5,000 kg/m3. Russian officials reported its aerial velocity at about 15 km/second and that it was about the size of a dinner table, so 4 meters across? If you tweak the velocity, density, size and angle a little, you get an airburst of between 2 and 5 kilotons of TNT, or a little less than half the strength of the atomic bomb that exploded over Hiroshima, and an explosion altitude upwards of 50,000 feet.

Seems like a pretty accurate calculation, although the actual altitude must have been more like 30,000 feet to produce the shockwave that resulted in all the injuries. Play around with the Impact Earth calculator and let me know if you get anything better!

Although asteroid 2013 DA14 is making a close flight by Earth today, zipping inside of some of our satellites, but this meteor event almost certainly had nothing to do with that. Space is full of stuff, and every so often we are reminded of that in spectacular fashion.

BONUS: This kind of thing happens all over the solar system. Check out this scorched explosion remnant on Mars!

(GIF via amalucky)

Twinkle- Geminids Kyle Hill, who writes the blog Science-Based Life, offers some thoughts on the deeply spiritual experience of staring up on a cold night, craning for the sight of a fleeting fireball. Except for Kyle, like many out there, that spiritual experience is not connected to a religion, or to God. For the many people out there who struggle to reconcile purpose and meaning while not believing in religion, it can be a lonely, and frustrating to express these awesome experiences to others, and even to yourself. Consider this: The common screed against the godless is that awe leaves us without a divine component, profound feelings are possible, but serve no purpose, as there is none. This is what they say. But anyone, anyone who looks up at the sky and contemplates but for a moment our place in the cosmos sees right through this fallacy. To attempt to grasp the universe in your mind’s eye is fundamentally awe-inspiring, and tonight’s meteor shower was a perfect vehicle to deliver such beauty into my night. No myths need spinning, no covenants need signing. The simplest way to unfettered wonder is, as Neil deGrasse Tyson puts it, to keep looking up. It is not my place, nor the place of others, I think, to demand that any individual to accept or reject belief in higher spiritual powers, and where I come from personally is not important. But when one is armed with the power to grasp the true nature of the universe using observation and curiosity, the spiritual experience of knowing can be deeply satisfying.  And that view of the world, seen in day or at night, should be welcomed by all.
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Twinkle- Geminids

Kyle Hill, who writes the blog Science-Based Life, offers some thoughts on the deeply spiritual experience of staring up on a cold night, craning for the sight of a fleeting fireball. Except for Kyle, like many out there, that spiritual experience is not connected to a religion, or to God.

For the many people out there who struggle to reconcile purpose and meaning while not believing in religion, it can be a lonely, and frustrating to express these awesome experiences to others, and even to yourself. Consider this:

The common screed against the godless is that awe leaves us without a divine component, profound feelings are possible, but serve no purpose, as there is none. This is what they say. But anyone, anyone who looks up at the sky and contemplates but for a moment our place in the cosmos sees right through this fallacy. To attempt to grasp the universe in your mind’s eye is fundamentally awe-inspiring, and tonight’s meteor shower was a perfect vehicle to deliver such beauty into my night. No myths need spinning, no covenants need signing. The simplest way to unfettered wonder is, as Neil deGrasse Tyson puts it, to keep looking up.

It is not my place, nor the place of others, I think, to demand that any individual to accept or reject belief in higher spiritual powers, and where I come from personally is not important. But when one is armed with the power to grasp the true nature of the universe using observation and curiosity, the spiritual experience of knowing can be deeply satisfying. 

And that view of the world, seen in day or at night, should be welcomed by all.

Source: sciencebasedlife.wordpress.com

Phobos: Doomed Moon of Mars This is Phobos, one of the two moons of Mars, and it’s living on borrowed time. It is thought to be perhaps a captured asteroid, sucked in by Mars’ gravity, and its pock-marked surface is scarred with craters thanks to debris ejected from its home planet’s own collisions with meteors and the like over the years. But Phobos won’t be around forever. Unlike our own Moon, which orbits at a safe distance of several hundred thousand kilometers (and will one day be “tidally locked” to Earth), Phobos is less than 6,000 km from Mars. This causes extreme tidal forces, stretching Phobos like saltwater taffy made of solid rock. Eventually, perhaps a million years from now, it will crumble into a ring of debris, with that ring later decaying into an orbital rainstorm of rocky meteoric fireballs. That’s pretty cool. Mars will eat its own moon one day, in a spectacular show of orbital destruction, and I’m sorry we won’t be around to watch. (via APOD)
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Phobos: Doomed Moon of Mars

This is Phobos, one of the two moons of Mars, and it’s living on borrowed time. It is thought to be perhaps a captured asteroid, sucked in by Mars’ gravity, and its pock-marked surface is scarred with craters thanks to debris ejected from its home planet’s own collisions with meteors and the like over the years.

But Phobos won’t be around forever. Unlike our own Moon, which orbits at a safe distance of several hundred thousand kilometers (and will one day be “tidally locked” to Earth), Phobos is less than 6,000 km from Mars. This causes extreme tidal forces, stretching Phobos like saltwater taffy made of solid rock. Eventually, perhaps a million years from now, it will crumble into a ring of debris, with that ring later decaying into an orbital rainstorm of rocky meteoric fireballs.

That’s pretty cool. Mars will eat its own moon one day, in a spectacular show of orbital destruction, and I’m sorry we won’t be around to watch.

(via APOD)

Source: apod.nasa.gov