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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

#101

Post by lucb1e »

SoftTalker wrote: post #92
lucb1e wrote: post #87

Earlier quoted context omitted.

> ~400m along it's biggest dimension Where did you find this information? I don't understand all the fields on the page, but don't see any number being 400 within an order of magnitude

400m in one dimension leaves a lot of room for variation. 400m x 1m x 1m is a lot less concerning than a 400m diameter sphere.

I wonder what the distribution is like; the most extreme length to height ratios we've seen for example. Not sure I've ever heard of something weirder than on the order of 2:1

Re: Asteroid ZTm0038 with a >3% impact probability

#102

Post by hoten »

mcint wrote: post #78
mcint wrote: post #63

Here's a visualization of its orbit, Earth in green, object in teal: http://orbitsimulator.com/gravitySimulatorCloud/yr/gsim2023.... It passed about 9 hours ago.

VSauce with packages summary for passive consumption. https://www.youtube.com/watch?v=4Wrc4fHSCpw And jacquesm's replies to my other comments, https://news.ycombinator.com/item?id=37139144

FYI VSauce is a different content creator than Veratasium (unaffiliated).

Re: Asteroid ZTm0038 with a >3% impact probability

#103

Post by fghorow »

amiralul wrote: post #44

Do we know how close it was?

According to a site [1] pointed to by another post in this page, the estimate for "Minimum Orbit Insertion Distance" was about 0.02 AU or about 3 million km (in round numbers).

Luna's distance is roughly 384,000 km -- so call it 8 lunar orbital distances...

(edited to add the link) [1] https://www.projectpluto.com/neocp2/mpecs/ZTm0038.htm

Re: Asteroid ZTm0038 with a >3% impact probability

#106

Post by postalrat »

SoftTalker wrote: post #92
lucb1e wrote: post #87

Earlier quoted context omitted.

> ~400m along it's biggest dimension Where did you find this information? I don't understand all the fields on the page, but don't see any number being 400 within an order of magnitude

400m in one dimension leaves a lot of room for variation. 400m x 1m x 1m is a lot less concerning than a 400m diameter sphere.

400x1x1 would be a pretty nasty spear that must have been made by someone.

Re: Asteroid ZTm0038 with a >3% impact probability

#109

Post by lucb1e »

> Closest approach time [...] t_max = 2023/08/15 12:22 TDB [...] Run started at 2023-08-14 23:51 UTC and ended at 2023-08-15 00:06 UTC

So this computation result became known after the closest approach would happen at the latest.

Looking at the asteroid I saw hitting us, 2023CX1 (known as Sar2667 before being designated), it says:

> Closest approach [...] t_max = 2023/02/13 03:22 TDB [...] Run started at 2023-02-13 11:47 UTC and ended at 2023-02-13 11:53 UTC

Again, hours after the impact actually occurred. And that's from the 7-observations page, there are 3 more pages with 28, 76, and 125 observations, all listed here: https://newton.spacedys.com/neodys2/NEOScan/index_past_imp.h...

The next one on the past impactors page has a 3 day delay between when it hit us and when its orbit was computed

What's the point of this?

Re: Asteroid ZTm0038 with a >3% impact probability

#110

Post by 1970-01-01 »

killthebuddha wrote: post #100

I'm having a weirdly difficult time finding some basic ELI5 answers. - What is the probability that this asteroid will hit us? - What is the time interval where that probability applies? - Do we have a probability distribution for where it might hit? I don't know anything about anything, but I assume we know what *general direction* it's coming from? - Do we have a probability distribution for the potential blast rad…

We need an expert to explain these facts and numbers. Until then, please buy necessary amounts of toilet paper.
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