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Phil Plait @BadAstronomer
, 12 tweets, 5 min read Read on Twitter
1/ 110 years ago today, an asteroid exploded over Siberia. It was… a *large* explosion. I wrote about it on the centenary so read all about this incredible event:

syfy.com/syfywire/100-y…

[artwork by Don Davis, @DDavisSpaceArt ]
2/ Why did the Tunguska impactor explode in the atmosphere instead of hitting the ground? Ah, I’m glad you asked:

syfy.com/syfywire/why-d…
3/ People have looked for a crater from the event, but none has been found. There have been *claims*, but I’m very skeptical:

syfy.com/syfywire/tungu…
4/ I’m even *more* skeptical about claims of meteorites being found from the event.

syfy.com/syfywire/have-…
5/ So you can imagine how I feel about claims of aliens blowing up the asteroid before it hit.

syfy.com/syfywire/alien…

Hey Zorplax, next time try doing that *before* it gets into our atmosphere. Sheesh.
6/ Back to reality: When can we expect the next big space rock to hit us? That’s actually a little bit difficult to answer.

syfy.com/syfywire/when-…
7/ If we see a space rock headed our way, what do we do about it? Why, I gave a whole TEDx talk about this very thing. Let’s save the world!

ted.com/talks/phil_pla…
8/ We’ve learned a lot about impacts. A LOT. Especially from the one that exploded over Chelyabinsk in Russia in 2013.

syfy.com/syfywire/one-y…
9/ I have a piece of that Chelyabinsk asteroid, BTW, a meteorite given to me by @RichardDrumm.
@RichardDrumm 10/ So asteroids are a threat, sure, but one we can do something about. And in the meantime they are way cool objects to study. Like Ryugu!

syfy.com/syfywire/what-…
11/ And soon OSIRIS-Rex will sidle up the small asteroid Bennu and we’ll learn even more!

syfy.com/syfywire/osiri…
12/12 Asteroids are amazing little beasties, and we’re getting very, very good at studying them. SCIENCE! Saving the world and learning about the Universe at the same time. It’s quite the bargain.
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More from @BadAstronomer see all

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1/ Today is #BlackHoleFriday, an annual science outreach event that, by complete coincidence I’m sure, is done on #BlackFriday. You’ll read lots of cool stuff about black holes on the hashtag. Here’s mine.
2/ Black holes are weird. Duh. People like to think of them as something like incredibly dense nuggets of stuff that sucks other stuff in. But they’re not like that.
3/ If you squeeze enough mass into a small enough volume, the gravity gets so intense that it’s impossible to escape them *if you get too close*. From far away, though, gravitationally they more or less act like anything with that much mass.
Read 19 tweets
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1/n This is quite seriously one of the most jaw-dropping observations I’ve ever written about:

Astronomers have detected material *just* over the edge of a black hole’s Point Of No Return.

syfy.com/syfywire/astro…
2/n Before I mention a thing or three about it here, I’ll note that the lead image is a *simulation* based on the observations. Don’t want to confuse people so I’m being up front. [P.S. Credit goes to ESO/Gravity Consortium/L. Calçada; link in the article]
3/n When I first heard the news, I figured the stuff had been detected indirectly. Maybe some effect on dust farther out, or an odd relativistic effect.

Nope. The motion was detected *directly*. In other words: They. Saw. The. Dust. Clouds. Move.
Read 10 tweets
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Hey, want some non-political news?

Ten billion years ago, the Milky Way ate a decently big galaxy. And we can still see the undigested bits floating around the sky!

syfy.com/syfywire/the-m…
2/ One of those undigested bits is the glorious Omega Centauri. It’s not only a massive globular cluster (w/millions of stars), it’s *the* most massive GC orbiting our galaxy. It may be the core of the galaxy that we ate eons ago!
3/ Omega Cen is so big and bright it’s visible to the naked eye! I saw it once by accident many years ago; huge coincidence and extremely lucky to spot it *just* over the horizon.

I was amazed, but now I know I may have seen the core of a long-lost galaxy.

Wow.
Read 5 tweets

Related threads

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#germanhistory
136 years ago today, #German #mathematician Felix Klein(1849-1925), then professor at #Leipzig University, wrote an interesting letter to his colleague Adolph Mayer(1839-1908), a letter which betrays Klein's indulgence towards the controversial theory of Cantor:..
.. » Leipzig, 15. 12. 1882 \\ Lieber Freund! \\ Vorgestern Nachmittag war Cantor lange hier und brachte mir eine Arbeit für die Annalen (Ueber ∞ lineare Punctmannigfaltigkeiten V) von merkwürdig speculativem Inhalt, von der er aus allerlei Gründen wünscht, dass sie recht bald..
.. publicirt werde. Ich habe ihm angeboten, dass wir die Separatabzüge umgehend herstellen, die officielle Publication aber bis zu geeigneter Zeit verschieben, und will nun, in der Voraussetzung, dass Ihnen die Sache so recht ist, heute Nachmittag in die Druckerei gehen und..
Read 17 tweets
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1/ This is a famous painting, "First Reading of the Emancipation Proclamation by President Lincoln”, by Francis Bicknell Carpenter:
2/ You can see Lincoln holding the Emancipation Proclamation while cabinet members such as Salmon P. Chase (standing at left) and William Seward (seated at right, facing Lincoln) listen.
3/ But this painting has almost as many documents and books as it has people. There’s the Proclamation itself, in Lincoln’s hand and (in a second page, I believe) on the table in front of him.
Read 63 tweets
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Five years ago today, two bombs exploded near the finish line of the Boston Marathon. Three people died, and hundreds were injured. Later that week, all hell broke loose in the Boston area. We still don't know who built the bombs.
In 2015, Dzhokhar Tsarnaev was found guilty of bombing the marathon and killing an MIT police officer. He was sentenced to death. The FBI seems to have moved on. But key facts in the case are missing. This is a thread about the loose ends.
The bombings happened on Marathon Monday, April 15, 2013, at around 2:50pm. For days, the government wouldn't say anything about whether it had suspects. Then, on Thursday April 18, at around 5:20pm, the FBI released photos of its suspects.
Read 64 tweets
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Today actually makes it over two decades since the sad killing of Ken Saro-Wiwa by the Nigerian State under Abacha alongside 8 others: Felix Nuate, Baronem Kobel, Saturday Dobee, Daniel Gbooko, Nordu Eawu, Baribor Bera, Paul Levura and John Kpuinee.

I think it’s worth a Thread.
This thread captures history from various perspectives all blended together to reveal a fuller picture.

It shows that Saro-Wiwa was also human like any of us but he was exceptionally courageous and dogged in spite of his human flaws.
Saro-Wiwa was a diminutive man who invariably always smoked a pipe and was considered quite brilliant.

He wrote a popular play which was adapted for TV when we were younger “Basi and Company”.

He was from Ogoni - an oil-producing area in Rivers State which has several villages.
Read 50 tweets
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Today is the 10-year anniversary of Mahmoud Ahmadinejad's Columbia speech
And now for a long, tedious thread about Mahmoud Ahmadinejad's appearance at Columbia's World Leaders Forum, 10 years ago today
I have a few vivid recollections of the day—I was 3 or 4 rows from the front, sitting a seat back from a Tehran-based Iranian journalist...
Read 42 tweets
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Y'know, it's at times like this, when I'm five minutes into watching BATMAN V SUPERMAN for the first time...
...and I've just watched a colony of bats levitate young Bruce Wayne out of a hole in the ground...
...and then it dissolves to white, with the title

METROPOLIS
MANKIND IS INTRODUCED TO THE SUPERMAN
Read 280 tweets

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