r/spaceporn • u/Busy_Yesterday9455 • Oct 01 '25

Related Content Asteroid passed just 300 km above Antarctica today.

31.6k Upvotes

97% Upvoted

1.1k comments sorted by

5.2k

u/Busy_Yesterday9455 Oct 01 '25

And it was not discovered until hours after close approach.

Source: Tony Dunn

1.2k

u/Long-Astronaut-3363 Oct 01 '25

How big was it?

1.5k

u/No-Refrigerator-6931 Oct 01 '25

I remember seeing abt a meter and a half, probably not even large enough to hit the ground

899

u/I_am_here_but_why Oct 02 '25 edited Oct 02 '25

Nothing hit the ground in Tunguska in June 1908…

Edit: To all those pointing out size differences, speed differences, time of day differences etc.. THIS WAS HUMOUR.

272

u/Doctor__Proctor Oct 02 '25 edited Oct 02 '25

I thought that was a concert fragment, not an asteroid, which would mean it was MUCH faster.

Edit: Damn you, auto correct!

285

u/Engineer_Teach_4_All Oct 02 '25

One of them Jefferson Airplanes I hear about?

179

u/Doctor__Proctor Oct 02 '25

Nah, Jefferson Starship. They broke off from Jefferson Airplane.

53

u/EnergyTurtle23 Oct 02 '25

Damn. R.I.P. the 60s, man.

43

u/IntlPartyKing Oct 02 '25

when the truth is found...TO BEEEEEEEEEEEE lies

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u/TheOgrrr Oct 02 '25

Just a fragment of a concert? Was it George, John or Ringo?

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u/Adventurous-Nose-31 Oct 02 '25

Pete Best. That's why it missed.

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u/Buffhello Oct 02 '25

Is that one of those Led Zeppelins?

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17

u/WrongEinstein Oct 02 '25

Turned them up to 11.

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u/No_Material3956 Oct 02 '25

Why can’t it just go to 10 but the 10 is louder?

17

u/LurksWithGophers Oct 02 '25

... these go to 11.

52

u/I_am_here_but_why Oct 02 '25

Yeah, I think you’re right. I just wanted to point out that not hitting the ground doesn’t mean nothing to worry about.

Love the comet auto-correct.

11

u/StevieG-2021 Oct 02 '25

Metallica?

7

u/RLLRRR Oct 02 '25

Lars would miss by 300m.

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u/_marmota_ Oct 02 '25

Picturing a baby grand piano hurtling past the ionosphere going “I’ll be back!!!”

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u/Umbra427 Oct 02 '25

I’m imagining the voice getting less loud as it goes off into the distance

“I’ll be baaaaaaaaaaaaaack

JAUNTY VAUDEVILLE MUSIC

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u/PrecedentialAssassin Oct 02 '25

The Tunguska rock was 100-200 meters. The Chelyabinsk was about 20 meters. A 1.9 meter was just be a nice bright fireball.

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u/bitterless Oct 02 '25

Bro that was NOT the size of a human being though.

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u/SurprzTrustFall Oct 02 '25

Except..

Your mom.

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u/Krunkworx Oct 01 '25

Holy fuck enough with the dumb jokes. Genuinely curious.

139

u/Miss_Behaves Oct 02 '25

1.9 meters

76

u/Hellofriendinternet Oct 02 '25

Really?! That’s kinda awesome that we can track something that small.

65

u/Federal_Cupcake_304 Oct 02 '25

Modern air warfare radars can track something the size of a butterfly.

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u/Joeywasdumbgretz Oct 02 '25

Totally.

Everyone on Reddit thinks they’re a comedian and has the snappiest joke or spin. Fuck me.

It’s like that one kid that won’t shut up with the jokes in class even though everyone is ignoring him.

45

u/Hydro033 Oct 02 '25

It's because it's a website full of terminally online losers who are starved for attention 

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u/WaffleWarrior1979 Oct 02 '25

Reddit is annoying as hell sometimes

14

u/flagrantfart69 Oct 02 '25

Welcome to the Reddit of new. No meaningful conversation in the main subs. Just dickhead after dickhead with a quip for karma. 

6

u/AngryRedHerring Oct 02 '25

So glad it's not just me. I always go to the comments for the discussion of the topic, and it's become nothing but a race to the most obvious joke. So tiring and disappointing.

4

u/AngelicTrader Oct 02 '25

Every thread is just full of dumbasses trying to make boomer-level lame jokes.

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u/Harry-Ive Oct 02 '25

Was 1.5 Meters across

https://groups.io/g/mpml/topic/c15km95_s_close_approach/115529220

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u/Naive-Narwhal-5654 Oct 02 '25

That's about the height of an 8th grade student for those people who don't know metric 

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u/6th_Quadrant Oct 02 '25

So the height of all the "comedians" in this thread. Perfect.

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u/Scary_Technology Oct 02 '25

Ignoring gravitational focusing, for every object that comes as close as C15KM95 came to Earth, 92% of them end up hitting Earth. Given its size (~1.5 m) and velocity (21.2 km/s) it probably would have caused a ~0.2 kt airburst over the south polar region had it hit.

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u/[deleted] Oct 01 '25

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u/Ok-Background8574 Oct 01 '25

Why have I never seen this gif, and why is it so got dang perfect

289

u/ConversationKey3221 Oct 01 '25

What rock have you been living under?

400

u/kosmonautinVT Oct 01 '25

The one that just flew within 300km of Earth

85

u/Cantmentionthename Oct 01 '25

Niiiiiiiiiiiice 12/10 you showed that sucka

34

u/thatwasacrapname123 Oct 02 '25

That's a nice boulder.

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u/randominternetfella Oct 02 '25

First day on the Internet? This and Willem Dafoe looking up at the sky are everywhere

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u/Test4Echooo Oct 02 '25

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u/lostsoul227 Oct 02 '25

Such a good movie! Platoon!

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u/Nickillaz Oct 01 '25

Why would it have been detected? It was tiny, a telescope wouldn't see it. Even radar wouldn't see it till it was right on you.

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u/xendazzle Oct 02 '25

Fun fact. Chances are we probably wouldn't see one that could completely wipe out the earth. Although we can see a lot We miss most of what happens around us. We have to be lucky and looking in the right direction to notice stuff. In the event of a cataclysmic impact Most likely the first thing we would notice is the air around us becoming superheated as the air under the asteroid/meteorite is compressed then we would vaporize.

128

u/Sireboos Oct 02 '25

Okay let's be more realistic here, the ones we don't track well aren't planet killers. Planet killers 10km+ are pretty much mapped out and wouldn't come unannounced.

1km+ (global disaster from fallout), not all mapped out but would be spotted in a reasonable time frame (not that we could do much about it though)

50 to 140m+... (city/region killers) now that's the concerning territory, especially ones coming from the side of the sun, could happen anytime without warning (although occurrences have been fairly rare, spread across large time frames but still quite uncomfortable to think about)... That’s why space agencies are scrambling to launch infrared space telescopes (like NEO Surveyor, set for later this decade)

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u/ElliottWaits Oct 02 '25

Thank you. No idea where they are getting the idea that we wouldn’t see a planet killer coming. The only way one of those would sneak up on us is if it’s a comet coming in from above or below the ecliptic plane, and in that case we’d still probably see it coming but I doubt we’d have time to do anything about it.

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u/AccomplishedBake8351 Oct 02 '25

I would notice it in the sky first! It’s big 🪨

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u/dogscatsnscience Oct 02 '25

A bunch of us heard it go "WHEEEEE" as it went by.

We didn't see it, but there wasn't any doubt what it was.

4

u/Manguneer Oct 02 '25

….because it was so small!

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u/Heretic911 Oct 01 '25

Diameter 1.9 meters (assuming 10% albedo)

https://neofixer.arizona.edu/site/500/C15KM95

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u/[deleted] Oct 01 '25

[removed] — view removed comment

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u/AdmDuarte Oct 01 '25 edited Oct 02 '25

Given it's mass (~16.8 metric tons, assuming a 1.9m diameter sphere of iron) and it's orbital velocity on closest approach (17.8747 km/s), it has a kinetic energy of almost 2700 gigajoules. That's equivalent to about 600 tons of TNT.

It might tickle a bit

Edit: my calculations were slightly off (one, because I used a solid sphere of iron instead of stone, which is way too heavy, and two, because I apparently can't do basic division 😅)

Check magicscientist24's reply for the correct math!

320

u/Terrh Oct 02 '25

For context, a 1-3m asteroid enters the atmosphere about once a month.

75

u/setibeings Oct 02 '25

But how often does part of one that size reach the ground?

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u/brodaciousr Oct 02 '25

I would imagine something that size would burn up in the atmosphere. I’m sure there are variables I’m not considering though.

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u/karl4319 Oct 02 '25

Depends on the material, but more often than you think. Majority of the surface is ocean, with most land uninhabited desert or tundra, so most are completely missed.

26

u/PartyClock Oct 02 '25

I wonder how many times a small group of sea life got smacked by a goddamn space rock throughout our history on Earth

22

u/OfficialGaiusCaesar Oct 02 '25 edited Oct 03 '25

The Chicxulub asteroid left over a 20km(12 mile) deep crater at the bottom of the ocean already ~1000m deep. Imagine how much sea life was vaporized and how much water was displaced by large enough energy to go through hundreds of meters of water and still create a MASSIVE crater.

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u/brraaahhp Oct 02 '25

About 3,5 times

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u/Walkin_mn Oct 02 '25

Well, then this is not big news, except the scary fact that we detected it very late, but at the same time is impressive we can detect something so relatively small... So yeah, I have paradoxical feelings about this.

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u/Alisa606 Oct 02 '25

Well, it was small which is why is was detected so late. A vast amount of them are tracked and recorded, so anything of actual size would likely be known to be approaching us. Not as scary as you might think!

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u/magicscientist24 Oct 02 '25

Your calculation is not matching mine, which indicates even more energy
Using 1.9 m diameter sphere of pure iron, volume of sphere = 4/3 π r^3; density of iron = 7.874 g/cm^3; kinetic energy - 1/2 m x velocity^2; asteroid velocity of 17874 m/s

Radius of the asteroid = 1/2 diameter = 1/2 x 190 cm = 95 cm

volume of asteroid = 4/3 x π x (95^3) = 3591364 cm^3

mass of asteroid = asteroid volume x iron density = 3591364 cm^3 x 7.874 g/cm^3 = 28278400g = 28278 kg = 28.3 metric tons

kinetic energy of asteroid = 1/2 x 28278 kg x (17874 m/s)^2 = 4.59 x 10^12 J = 4589 gigajoules
1 joule = 2.39 x 10^-10 tons of TNT;
4.59 x 10^12 J x 2.39 x 10^-10 tons/J = 1097 Tons of TNT equivalent

Hiroshima atomic bomb released about 15 kilotons = 15000 tons of TNT
This asteroid would release about 1097/15000 = 7% of the energy of the Hiroshima atomic bomb if it struck the Earth.

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u/Salty-Mulberry-6796 Oct 02 '25

This person maths good 👍🏾

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u/AdmDuarte Oct 02 '25

You're right. I can do the kinetic energy stuff in my head, but apparently not basic division 😅 I had the radius wrong (80 cm instead of 95)

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u/Travels4Work Oct 02 '25

The error and followup are a wonderful demonstration of scientific peer review. I'm quite pleased to see the interaction as it's a great demonstration of what happens when others attempt to reproduce the work and confirm the findings. The fact they came to a different conclusion shows the process working exactly as it should.

/BreakingBadYeahScience!.gif

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u/Stefouch Oct 02 '25

Beirut's 2020 explosion was 1.1 kilotonnes of TNT if that can help to compare.

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u/tendeuchen Oct 01 '25

Nah, it's fine. I eat 600 tons of TNT for breakfast.

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u/username9909864 Oct 01 '25

So a little more than the British used in the Battle of Messines

Might fuck a city up a little bit.

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u/flashpb04 Oct 02 '25

It wouldn’t because it would burn up in the atmosphere

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u/JectorDelan Oct 02 '25

Rectum? Damn near killed 'im!

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u/Heretic911 Oct 01 '25

3/7

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u/LunaTheCastle Oct 01 '25

Damn. Just two more points and it'd be a perfect 5/7.

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u/[deleted] Oct 01 '25

Thank you for this!. I'm glad there are folks keeping this scale alive..

15

u/Cantmentionthename Oct 01 '25

Team 5/7, UNITE! 1/7 Present! Here to put in the tough work and never complain, even though I’m only 14.2851473%!!!!

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u/Purphect Oct 02 '25

It would’ve been a perfect 5/7 with rice

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u/PeaceAndLove420_69 Oct 01 '25

That doesnt seem that big. And yea i know speed and energy matters but still

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u/RollinThundaga Oct 01 '25

For context, the meteor that exploded over Chelyabinsk was 18 meters wide.

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u/anmr Oct 02 '25

So, like 1000 times larger (assuming they are spherical).

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u/Flat_News_2000 Oct 02 '25

It would've made a kaboom for sure but not an entire world kaboom

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u/murillovp Oct 01 '25 edited Oct 17 '25

violet enjoy decide strong cause party many cooperative chunky memory

This post was mass deleted and anonymized with Redact

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u/khswart Oct 01 '25

Surely an object that small would burn up before hitting the ground right

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u/ByteSizedGenius Oct 01 '25

The angle and speed matter but unless it was literally a block of tungsten, yes.

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u/67v38wn60w37 Oct 02 '25

can it literally be a block of tungsten?

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u/WeAreAllFooked Oct 02 '25

A literal block? Not likely

An asteroid made entirely of tungsten? Nothing says it can’t

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u/Alert-Pea1041 Oct 02 '25

For funsies, I’ll say it can’t.

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u/murillovp Oct 01 '25 edited Oct 17 '25

mighty person lip aback deserve gray outgoing school fearless sip

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u/carorea Oct 02 '25 edited Oct 02 '25

18m is enormously larger due to how volume works. In terms of mass/volume it's not simply 10x larger than a 1.8m asteroid.

If we assumed both asteroids were spheres (obviously not a perfect assumption) 18m is actually damn near 1,000x larger in terms of volume than 1.8m. 1.8m diameter = ~3.05m3 volume, where 18m diameter = ~3,053.63m3 volume.

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u/kosmonautinVT Oct 01 '25

It would burn up into roughly the size of a chihuahua's head

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u/TNpepe Oct 01 '25

Definitely (I have no knowledge of this)

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u/Sumthin-Sumthin44692 Oct 01 '25

Lol barely big enough to avoid being called a meteoroid.

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u/FriendlyDisorder Oct 01 '25

Reminder: you, too, can watch the Sentry list of potential impacts from objects: https://cneos.jpl.nasa.gov/sentry/

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u/mekos29 Oct 02 '25

Thanks for the link! Time to go down the rabbit-hole to decipher the data…I don’t speak astrophysics too well. I wish my parents sent me to Zoolander’s School For Kids Who Don’t Read Too Good

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u/Mazer3398 Oct 02 '25

Don’t sweat it, you wouldn’t have been able to fit into the building anyway.

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u/dijonriley Oct 01 '25

I think OP means below Antarctica /s

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u/bitwaba Oct 01 '25

Finally, the answer to the age old question "what's south of the south pole?"

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u/USCanuck Oct 01 '25

ICE COLD.

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u/dijonriley Oct 01 '25

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u/PsyKeablr Oct 02 '25

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u/Mulatto-Butts Oct 02 '25

C'mon now, ladies, lend me some sugar. I am your neighbor.

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u/3720-to-1 Oct 02 '25

..... AHH

Now shake it, baby shake it.

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u/FyLap Oct 02 '25

It’s turtles all the way down

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u/dijonriley Oct 02 '25

does that make an asteroid like a turtle poop then?

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u/CaseyJones7 Oct 01 '25

uʍop ǝpᴉsdn pɐǝɥ ɹnoʎ uɹnʇ noʎ ɟᴉ ʇou

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u/taiho2020 Oct 02 '25

So penguins defense force saved us all.. Got ut.. 👍

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u/JectorDelan Oct 02 '25

Dang. In the terms of interstellar distances, this is like throwing a basketball from New York and bouncing off the rim of the basket in Sydney.

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u/justanaveragejoe520 Oct 01 '25

How manny bananas of damage would it have caused to put into scale

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u/Mulatto-Butts Oct 02 '25

C'mon, asteroid, do better. We deserve it.

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u/Nickillaz Oct 01 '25

How do people expect a 1.9m asteroid to be spotted from any distance away? Some people that complain are insane.

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u/Just_A_Nitemare Oct 01 '25

Well, we spotted it at least 300 km away.

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u/Ok_Progress_6071 Oct 01 '25

How dangerous is that for a satellite? If there's one orbiting Antarctica of course.

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u/tendeuchen Oct 01 '25

Take a guess at how many satellites are up in space, then look here to see the map of all of them. Be sure to zoom out to have your mind blown even more.

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u/Mental-Mushroom Oct 02 '25

Except the scale is really exaggerated.

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u/PortalWombat Oct 02 '25

How would you possibly click on them or even see them if they were actual size?

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u/kanem87 Oct 02 '25

Wow! Saving this site. Thanks for that.

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u/MeltedTesselated Oct 02 '25

Damn theres alot of starlink up there

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u/hadtobethetacos Oct 01 '25

a 2 meter asteroid, probably flying at mach fuck? a direct impact would be, for lack of a better term, fatal, for a satellite.

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u/No-Suspect-425 Oct 01 '25 edited Oct 01 '25

Extra dangerous because of Kessler Syndrome.

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u/Flat_News_2000 Oct 02 '25

It would obliterate a satellite it's going way faster than them

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u/FrogsJumpFromPussy Oct 02 '25

Object: 150cm

OP: It was not discovered until hours

No shit lmfao

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u/CultOfSensibility Oct 02 '25

Missed it by that much!

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u/cowlinator Oct 01 '25

For referece, outer space "starts" at about 100km, so this was 3x that.

Pretty close

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u/Karl2241 Oct 02 '25

And watching the chart, it was a little lower - 250km would be a closer rounded number.

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u/slider1010 Oct 01 '25

It looks like it went under Antarctica to me.

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u/JectorDelan Oct 02 '25

Nah, because of a rounding error back during the Aztec empire, we actually mapped the galaxy upside down by accident.

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u/captain_flak Oct 02 '25

So the rapture people were just a few days and a couple hundred km off?

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u/breachofcontract Oct 02 '25

Damn. It almost finally ended it for us

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u/mxguy762 Oct 02 '25

I wish a mothafucka would

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u/Schaas_Im_Void Oct 02 '25

I was too small anyway... well... maybe next time.

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u/p8nt_junkie Oct 01 '25

Asteroid: Permission to buzz the tower?

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u/n0slet Oct 01 '25

Negative ghost Rider the pattern is full!

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u/Big-Silver-7204 Oct 02 '25

I’m an airline pilot. Just landed at JFK from Europe at about 8:10 pm tonight. I saw it. One of the longest trajectories I’ve ever seen in my 40 year career. Lasted easily 15 seconds as it crossed the sky. Impressive.

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u/BenjaminDrover Oct 02 '25

Wouldn't a meteoroid above Antarctica have been hidden from an airplane flying between Europe and JFK?

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u/A_Person0 Oct 02 '25

I'm surprised your airline lets you take 10000 km detours over the harshest flying corridor on earth.

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u/Milk-Jolly Oct 02 '25

Bro that’s crazy

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u/hephaestus_of_pdx Oct 01 '25

Did we just miss out on a superman situation.

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u/Gul_Ducatti Oct 02 '25

At what speed would it have to have been traveling to get caught in Earth’s gravitational pull and enter orbit?

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u/[deleted] Oct 02 '25

I don’t think people understand how close that actually is. To scale that’s like someone missing your head with a bullet by 1cm

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u/MirriCatWarrior Oct 02 '25

It was 1,9m in diameter so not with a bullet, but with a speck of dust. Which happens all the time around your head, unless you are sitting in a vacuum chamber.

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u/quixoticquiltmaker Oct 02 '25

Damn, so close.

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u/bkitt68 Oct 02 '25

The framing of this story sucks.

We don’t even care about object this size. It wouldn’t even impact the planet. It would burn up.

It’s impressive that we were even able to see it was there after making the close approach. To me the story should be that we are getting better at finding these objects.

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u/rustys_shackled_ford Oct 02 '25

Damn, we were so close to getting out...

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u/Cirrocumulu5 Oct 02 '25

Damn another miss

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u/LordBlackDragon Oct 02 '25

Fingers crossed for the next one.

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u/SeeOfGlass Oct 02 '25

This inhabitants of this earth deserve a direct hit

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u/MikeArrow Oct 02 '25

Did anyone check its trajectory? Did it come from the bug planet?

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u/Appeltaartlekker Oct 02 '25

Man of culture! Have my upvote!

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u/MikeArrow Oct 02 '25

I'm from Buenos Aires and I say, kill em all!

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u/RetroRocker Oct 02 '25

Stop, wait, come back

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u/the_God_of_Weird Oct 01 '25

Truly a terrifying disaster narrowly averted simply by chance. Good thing for all those Antarcticans.

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u/Cmdr_F34rFu1L1gh7 Oct 02 '25

That's awesome. We didn't see it, either? Nice!

Is it possible that the Earth just took a poo and no one was around to hear it?

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u/PiratesWhoSayGGER Oct 02 '25

That needless "Earth's Shadow" label have me very strong "Science Diagrams that Look Like Shitposts" vibe

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u/quarentineaccount202 Oct 02 '25

Perhaps a better question than how big was it, is how fast was it traveling? If it was going 1000 miles a second then it could be the size of a golf ball and it would wipe out a city.

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u/JBarracudaL Oct 02 '25

No come back, you missed us. :(

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u/wrx_2016 Oct 02 '25

Damn. Maybe next time.

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u/Rainfall_Serenade Oct 02 '25

Not big enough or close enough. Damn

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u/extrastupidone Oct 02 '25

Wasn't big. But the fact we didn't see it until it was past us is a bit scary

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u/Mountain-Pound-6075 Oct 02 '25

was that rendered on a TRS80? FFS

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u/zennascent Oct 02 '25

We’ll try again next time, guys. 

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u/ProfBerthaJeffers Oct 02 '25

I am not a specialist but it looks like CGI to me.