A 390FT rock will scrape past Earth closer than the Moon tomorrow | Hacker News Reader

A 390FT rock will scrape past Earth closer than the Moon tomorrow

express.co.uk

37 pointsLinuxBender13 comments

Despite being large (390 ft, or ~130 meters for us using the metric system), its composition (mostly solid ice) makes it so that in the case of the wrong trajectory and an impact on Earth, most of it is supposed to evaporate and burn; it would quickly be fragmented in thousands of pieces, and have huge impacts in a small area, and almost no impact to the Earth's ecosystem. This is AFAIK, and I am not an astronomer or an expert. Please correct me if I am wrong. Unfortunately there's no Palermo Hazard scale for this particular asteroid [0].

There's some very relevant Wikipedia pages about the subject [1], [2].

[0]: https://en.wikipedia.org/wiki/Palermo_Technical_Impact_Hazar...

[1]: https://en.wikipedia.org/wiki/Impact_event#Geological_signif...

[2]: https://en.wikipedia.org/wiki/Asteroid_impact_avoidance

So the headline is that a near-Earth object is not only going to miss Earth by a wide margin, but also even if it did hit us nobody would notice...

People would definitely notice. A 390 foot meteor bursting into many smaller meteors is still going to be a spectacular show (and likely cause some damage.)

It's just not going to be an extinction level event.

Even a 390 ft nickel-iron meteor would only be dangerous if it entered over populated areas and the odds of that are low.

Well, assuming my very basic math is right. As said, I am not an expert, and I might be very wrong about how that scenario would have played out.

I'd be curious how many other bodies pass within specific distance ranges every year.

Is this rare or pretty common?

This reporting is terrible (and pretty hard to read) but here's a cool graph of the approach to Earth: https://theskylive.com/how-far-is-2019od

In a similar vein, I built this orbital simulation that shows the orbits of 2019 OD and Earth: https://www.spacereference.org/solar-system#ob=2019-od

Along with a more level-headed collection of facts about the asteroid, which is not classified as Potentially Hazardous: https://www.spacereference.org/asteroid/2019-od

Volcanism is a much greater threat to civilization than meteors.

In the past 1500 years, at least three eruptions have caused global crop failures: Tambora, Samalas, Ilopango.

Vulcanism has a ... generally ... bounded upper scale,[1] astronomical impactors do not, and demonstrably modest impactors have had devastating results, with numerous candidates existing. Fortunately they're sparsely distributed.

________________________________

Notes:

1. Volcanic traps caused by flood basalt eruptions being an extreme outlier upper bound, see the Siberian Traps, 500 million ya, as a notable example.

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

There have been 18 identified, most 100s of millions to billions of years ago, though as recently as 10 mya. Yellowstone is among the younger (17 mya). The events may be associated with meteor impacts as well -- evidence is poorly preserved.

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

Any idea if this will be visible from the ground anywhere? I've been searching online to no avail.

Here you go: https://www.spacereference.org/asteroid/2019-od

Thanks for that, very interesting. Couldn't quite figure out whether I'd be able to see/photograph it from Australia during the night but then again I'm pretty clueless.

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