The Shooting Gallery In Which We Live

2013 a 440 kiloton explosion happened over Russia. A rock from space. More recently, a 173 kt explosion happened off the coast of Alaska.

From: https://cneos.jpl.nasa.gov/fireballs/

Note that the scale is “Log kt” of explosive energy. The top end is about 2.5 so huge. Click on it to embiggen.

Fireballs In The Sky...

Fireballs In The Sky…

Many of the bigger ones are remnants of the breakup of Comet Encke. In an earlier larger form it is most likely the source of the chunk that caused the Younger Dryas impact event.

Makes you kind of glad we have all that air over head…

The Earth moves across the swarm of rocks that makes up the Taurids. Right now we are out of the center highest density area, so every few years we get a nice light show of minor fragments. Longer term the center of the mass arrives when we are near the center of the swarm track, and then we get a lot more. One theory is that the (roughly) 3000 year cycle of catastrophe is driven by those orbital mechanics.

I find it amazing we have so many kiloton and more explosions, and so few folks seem to notice…

Subscribe to feed

Advertisements

About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
This entry was posted in Earth Sciences, History, Science Bits and tagged , , , , , . Bookmark the permalink.

4 Responses to The Shooting Gallery In Which We Live

  1. ossqss says:

    Supplemental resource for such in addition to an umbrella :-)

    https://cneos.jpl.nasa.gov/about/target_earth.html

  2. Larry Ledwick says:

    So the upper limit of that scale log(kt) ~= 315 kt equivalent yield. That is about 3x the yield of most ICBM warheads (about 110 kt).

    The majority of them are in the range of the Hiroshima blast yield it looks like, but as almost all of them detonate at high altitude and out in the expanse of the ocean little ground effect except for some rattled windows most of the time.

    The Chelyabinsk meteor is estimated to have been 400–500 kilotons energy or slightly off scale high on that plot. After the fact they discovered a security camera video that shows the impact of the chunk that hit the ice on lake Chebarkul at about 700 ft/sec (about 460 mph).

    https://slate.com/technology/2013/11/video-chunk-of-chelyabinsk-meteorite-hitting-frozen-lake.html

    If you assume the frequency is essentially constant over human life spans and the size distribution is uniform over the slightly less than a century since Tunguska in 1908 it is probable that other similar impacts happen often enough to occur within human memory.

    They now estimate that Tunguska events are 200 – 1000 year events, so if correct it is not unreasonable to expect a similar event in the lifetimes of some reading this blog.

  3. Steven Fraser says:

    We get hail in Texas, 3/4 of a pound. Does that count?

  4. H.R. says:

    @Steven – Hail, no!

    I speak Texan as a second language ;o)

Anything to say?

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.