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Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

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Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#61

Post by dard »

I work on the NEO Surveyor space telescope, doing orbit simulations of asteroids/comets and predicting expected observations of objects like these.

If you look: https://www.minorplanetcenter.net/db_search/show_object?utf8...

You will see this was actually spotted back in 2014, but only seen for a few days. When an object is only observed for a few days we generally cannot compute an orbit for it, there is just not enough data to pin it down. However during this current pass of it (the last time it will come by for at least a few centuries), we have enough observations to pin its orbit down. Note that a lot of this is automated nowadays, with automatic observation and "interesting" objects being flagged automatically. There are a lot of small rocks up there (sub 100m).

Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#62

Post by phkahler »

dard wrote: post #59
phkahler wrote: post #4

"Maybe the big take-home point on this one is it's a pretty big object and it was only found 10 or 12 days before closest approach," I've said this before. The way they find these things is looking for movement against the distant background / starfield. That works pretty well for finding things, but there is one problem. Any object on a collision course with earth will NOT be moving across the background in the days…

I actually work on NEO Surveyor telescope (surveying for dangerous asteroids), writing the simulation code use to track expected performance. So simulating +20 million asteroids and what will be visible during the mission. Motion is how we determine if there is an asteroid or just some static sky source (IE: star). However your comment is not correct, everything moves, even in the days leading up to a potential impac…

Earth is about 8000mi across. The moon is about 239000mi away. Looking at it from opposite sides would be about 0.016 degrees of angular displacement. And that's a couple days from impact.

>> So simulating +20 million asteroids and what will be visible during the mission.

How many impacts do you simulate? These are the ones we care most about, and I still think they will be the hardest to detect.

Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#63

Post by dard »

phkahler wrote: post #62
dard wrote: post #59

Earlier quoted context omitted.

I actually work on NEO Surveyor telescope (surveying for dangerous asteroids), writing the simulation code use to track expected performance. So simulating +20 million asteroids and what will be visible during the mission. Motion is how we determine if there is an asteroid or just some static sky source (IE: star). However your comment is not correct, everything moves, even in the days leading up to a potential impac…

Earth is about 8000mi across. The moon is about 239000mi away. Looking at it from opposite sides would be about 0.016 degrees of angular displacement. And that's a couple days from impact. >> So simulating +20 million asteroids and what will be visible during the mission. How many impacts do you simulate? These are the ones we care most about, and I still think they will be the hardest to detect.

Here is a simulation I did in response to your comment, this is ~6 million impactors and their on sky velocity as they approach Earth. Dotted black line is our expected detectability limit, anything to the right of that is detectable. On sky velocity is measured in degrees / day.

https://www.dardahlen.com/6m_impactor_vel.png

Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#64

Post by reaperman »

dard wrote: post #63
phkahler wrote: post #62

Earlier quoted context omitted.

Earth is about 8000mi across. The moon is about 239000mi away. Looking at it from opposite sides would be about 0.016 degrees of angular displacement. And that's a couple days from impact. >> So simulating +20 million asteroids and what will be visible during the mission. How many impacts do you simulate? These are the ones we care most about, and I still think they will be the hardest to detect.

Here is a simulation I did in response to your comment, this is ~6 million impactors and their on sky velocity as they approach Earth. Dotted black line is our expected detectability limit, anything to the right of that is detectable. On sky velocity is measured in degrees / day. https://www.dardahlen.com/6m_impactor_vel.png

Amazing work to share so rapidly in this context! The results of your simulation and this discussion will stick with me for a long time. Thank you!

Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#65

Post by phkahler »

dard wrote: post #63
phkahler wrote: post #62

Earlier quoted context omitted.

Earth is about 8000mi across. The moon is about 239000mi away. Looking at it from opposite sides would be about 0.016 degrees of angular displacement. And that's a couple days from impact. >> So simulating +20 million asteroids and what will be visible during the mission. How many impacts do you simulate? These are the ones we care most about, and I still think they will be the hardest to detect.

Here is a simulation I did in response to your comment, this is ~6 million impactors and their on sky velocity as they approach Earth. Dotted black line is our expected detectability limit, anything to the right of that is detectable. On sky velocity is measured in degrees / day. https://www.dardahlen.com/6m_impactor_vel.png

Thanks, that's really cool. And the detectability line is under 0.01 degrees per day, so the parallax from opposite sides of the earth is well within detectable at lunar distance. You also confirm that the detectability (due to motion) is dropping as the time to impact decreases, but this is apparently not a problem. Leave it to projects run by physicists to have exquisite measurement precision ;-)

Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#66

Post by dorkNiner »

delta_p_delta_x wrote: post #56
funcDropShadow wrote: post #55

Earlier quoted context omitted.

> About 5-10 years' warning would be enough time for a large nuclear device to deflect such an asteroid The asteroid in this article was detected 2 weeks ago.

Precisely why we ought to step up our detection.

Really, we should have a moon base, 6 years ago. This makes me very anxious. We have all our eggs are in one basket.

As for detection there's some of them are coming from the other side of the sun, the one that Jupiter throw at us, It would be good to have a few more detection at L4, L3, It would be good to know what part of the earth is going to get hit. And evacuate them. Having a moon base off planet would be able to make all this coordination possible, because the amount of chaos that it would cause.So it needs a large gain antenna like the one that's in Australia that the Intuitive Machines lander low gain antenna was able to make two way contact with. The same one that was used to televise the Apollo missions.

I just can't, I can't emphasize enough the advantages to working and living on the moon. Shift all energy production all these experiments terraforming and such eco engineering To there just terraform one crater and start growing some plants . It shouldn't have been done so many years ago. It could be done with one pre-supply mission with a Falcon 9 and an Oberth Pumping orbit and then followed by a manned mission. Where the falcon heavy and dragon? The mayby recovered the second stage on the moon. It's just been over thought, overly planned. I mean, against nature, we're nothing. It's impractical to think that we can. can't stop a meteor. We're never going to see it coming. We don't have five years to plan that I mean. I'm even surprised that any of the simulations converge . You know, don't need to be adjusted. We don't even have gravity physics consensus.

I can't be done on a Earth because it becomes someone else's problem far away because it usually backfires diffuses through the air in the sea. It does not happen on the moon. So I mean, you can make this terrible meltdown reactor and then just leave. Leave it in a crater. Those gamma rays are not going anywhere except up. I just put a thing that says no fly zone over it.

Seems that we put a lot of effort and money into these overly ambitious projects like going to Mars, which has absolutely no practical advantage when leaving the moon up there, unused. I mean, this isn't about Space tourism t's about survival. making the moon an exporter. It has everything that we don't have, but that we're running out of, rare earth minerals. oxygen. The only thing that's missing is carbon dioxide. And we're going to be bringing that. And as soon as the plans we grow up there, using that 24/7 solar. solar power. and have a greenhouse. All we have to do is breathe the air they make. They can extract oxygen from the regular and we can do it too with heat. And we can sublimate iron and build stuff. We can, we can figure out how to sublimate titanium from titanium dioxide. I mean, the conditions are so ideal. We we would go there cause it because we think it's easy. When we go there because we thought it would be easy, right? But right now, I think we think is is going to be a lot harder than it really is. There's sweet spots on them. Lunar S pole that are just 20 degrees C. To send stuff back down to Earth, you just have to shoot it at 2400 kph The railgun. will fall back down to Earth will take long. Superconductor is in permanently shadowed craters are almost sort of Ambient temperature. if not already. Type B, type 2 or whatever.

Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#67

Post by dorkNiner »

dard wrote: post #63
phkahler wrote: post #62

Earlier quoted context omitted.

Earth is about 8000mi across. The moon is about 239000mi away. Looking at it from opposite sides would be about 0.016 degrees of angular displacement. And that's a couple days from impact. >> So simulating +20 million asteroids and what will be visible during the mission. How many impacts do you simulate? These are the ones we care most about, and I still think they will be the hardest to detect.

Here is a simulation I did in response to your comment, this is ~6 million impactors and their on sky velocity as they approach Earth. Dotted black line is our expected detectability limit, anything to the right of that is detectable. On sky velocity is measured in degrees / day. https://www.dardahlen.com/6m_impactor_vel.png

thanks I think that that's really kind of scary, but motivational as to putting up a moon colony so that we just have a 2n base. H But I have. have a few questions. If you've got a minute, must be nerve wracking to work there.

looks like it would be coming from the sun's direction because it is kind of a. dominating force , but i wonder why a couple days after a flyby is when they are often detected. Is it just because the sun is able to light/heat it up more?

Also, I'm wondering what software you use to to do the modeling for one. And if it's open source. and if it's reversible , so you can back it up and fix positions when new datas comes in

https://en.wikipedia.org/wiki/Fermi%E2%80%93Pasta%E2%80%93Ul... That was done at Los Alamos with a Maniac and the first version was fixed point, but as you can see it looks chaotic, but then there's a semi ring. There's a repetition. So I I'm guessing that's why that we care about are flybys. They go by once and at some point they'll come back.

https://www.josstam.com/reversible

  This might help if you click the reversible to use  fixed point. you can go back and and retrace.. the steps even with a rough integration.
as soon as you have a correction for any of them, you can place that correction. By reversing the entire model or the solver.

I'm guessing there's such a cloud of objects you use something like. Fluid solver, even if you had to do that to some other body, then may have had an influence on the body that's under investigation, and you have new data for that, it might help to make the prediction more accurate. And without introducing any discontinuities in the model, if the past positions help determine the future ones going back.

You can see here (Stam) that even though it's chaotic like an N body problem, there is a semi ring and it repeats. So what appears to be maybe chaotic over time would be periodicity of the lineup. Then it seems, though, when certain planets are lined up. It's more likely that it's gonna have this this. confluence of Of gravitational influence. that will bring it in our direction. I'm thinking thinking Jupiter, Mars, the moon and the sun and the earth in between. Jupiter all the way to the earth is basically one orbit. At that velocity S50 kilometers uh second.

Also, I wonder if. the if something hit the back of the moon, would we even notice that until we go to the back of the moon or with a lunar reconnaissance or over and we find some craters that have direct impacts so that it would have could have been our planet killer. I'm sure there's quite a few up there with some some markings that will indicate that it probably injected some heavy metal right at that very crater. A direct hit. The moon was in the way because the the lineup of the two bodies ,that caused the dynamic in the first place. I'm guessing here.

Thanks again for making that chart.

Re: Discovered June 16th, large asteroid to pass between Earth and moon on Saturday

#68

Post by dorkNiner »

squigz wrote: post #47
SoftTalker wrote: post #26

Earlier quoted context omitted.

> start prepping for accepting of loss of life If they knew it was going to hit, but not be an extinction event, maybe that makes some sense but realistically what kind of "prepping" can reasonably be done? Stock up on toilet paper? If they knew it was going to hit and incinerate the surface of the earth, would they even say anything? Why create worldwide panic for no purpose?

> If they knew it was going to hit and incinerate the surface of the earth, would they even say anything? Why create worldwide panic for no purpose? Assuming 'they' knew it was a world-ending event... good luck getting everyone involved to not say anything to anyone, including their loved ones. I also imagine there are several agencies doing asteroid detection, so it's not like it's just NASA personnel we have to wor…

The record shows many long winters,4 close tree rings. Global and in same strata. about 5000 yrs. So how can we survive that 4 winters? not impossible if coms,radio, light boards ,satellite messages.. and civility are maintained.During the Black death in England, funerals,and wills kept civility.

the lunar base can provide terra firma form dropping supplies and there's startups in that. i even proposed to AIG insurance company a lunar escape resort as futures,funding miners via from invested premiums into managed derivatives and holdings.moon should be a net exporter or technology and rare earth.

i'm late to this discussion but i work on unified gravity, its close, we had it a long time but its getting to be beautiful & simple. verifiable so far. other possibility: A two burn oberth can zip a falcon heavy with high 50km/s towards a meteor if we saw it coming. this should be the 1000x higher priority over wars and genocides and pandemics and Gucci bags and mars fantasies and VR.

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