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Asteroid ZTm0038 with a >3% impact probability

newton.spacedys.com

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Re: Asteroid ZTm0038 with a >3% impact probability

#51

Post by H8crilA »

ortusdux wrote: post #33
FredPret wrote: post #21

I plugged this into neal.fun/asteroid-launcher. I'm not sure if I did it right (I used the 15.84 km/s as impact speed, picked 45 deg impact, and an iron asteroid). It's certainly serious - millions dead - especially if it hits Manhattan as neal.fun seems to invite you doing, but not world-ending.

I used the Earth Impact Effects Program calc w/ 90 deg impact, rock asteroid, and 15km/s. https://impact.ese.ic.ac.uk/cgi-bin/crater.cgi?dist=100&diam... 4 mile crater, 2300 MT of TNT equiv. so about 45 Tsar Bombas.

Where did you find the mass/size?

Re: Asteroid ZTm0038 with a >3% impact probability

#53

Post by jacquesm »

babelfish wrote: post #16
xwdv wrote: post #3

Not threatening, mostly harmless.

[flagged]

Based on even the slightest bit of checking you could see that that number is utter bullshit, 5Kt is nothing at all like the impact of an asteroid of this size.

https://en.wikipedia.org/wiki/Chelyabinsk_meteor

Was 100 times as much and was only an 18 meter asteroid.

Re: Asteroid ZTm0038 with a >3% impact probability

#55

Post by mcint »

post_break wrote: post #24

How long ago was it spotted. That's what I'm curious about, did we have any lead time?

3 days ago, it was first seen. About a dozen observations. F***, it's not fun that these pass with so little forewarning.

   ZTm0038* C2023 08 12.49542 06 32 33.23 +15 57 35.5          18.86rUNEOCPI41
Is the first entry, and asterisk-marked, on https://cneos.jpl.nasa.gov/scout/#/object/ZTm0038 at the bottom, in the Observations section.

Unusual (new to me) format. Appears to me, first guess to read:

   [object] [yr] [m] [day.time-decimal] [position] [elevation-angle]   [observatory]
Likely oriented relative to the plane of the ecliptic, and absolute direction relative to Earth at time of observation.

Re: Asteroid ZTm0038 with a >3% impact probability

#58

Post by jacquesm »

version_five wrote: post #49

Is there an english / eli5 if you like, summary of what this means? I gather that today or yesterday an asteroid ~400m along it's biggest dimension ultimately came within x km of earth, that was close enough there was a nontrivial chance it would hit us? And this is big enough to make a 30 mile crater? And we only found out it was coming a couple days ago? Sounds like a pretty big deal if that's accurate.

It's accurate and it could have been a pretty big deal but for now it isn't, unless there are very low magnitude companions to it that hit unexpectedly because they have not been observed at all. There is some precedent for that sort of thing.

Re: Asteroid ZTm0038 with a >3% impact probability

#59

Post by throwanem »

brink wrote: post #11
xwdv wrote: post #10

Earlier quoted context omitted.

Only 400m in diameter.

How much of that would burn up in the atmosphere if it did hit?

The better question to ask is, how much energy would that transfer to the atmosphere on its way to dumping the rest into the planet proper?

Re: Asteroid ZTm0038 with a >3% impact probability

#60

Post by mcint »

mcint wrote: post #55
post_break wrote: post #24

How long ago was it spotted. That's what I'm curious about, did we have any lead time?

3 days ago, it was first seen. About a dozen observations. F***, it's not fun that these pass with so little forewarning. ZTm0038* C2023 08 12.49542 06 32 33.23 +15 57 35.5 18.86rUNEOCPI41 Is the first entry, and asterisk-marked, on https://cneos.jpl.nasa.gov/scout/#/object/ZTm0038 at the bottom, in the Observations section. Unusual (new to me) format. Appears to me, first guess to read: [object] [yr] [m] [day.time-d…

Here's a visualization of its orbit, Earth in green, object in teal: http://orbitsimulator.com/gravitySimulatorCloud/yr/gsim2023....
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