19 ms·
Asteroid ZTm0038 with a >3% impact probability
- deleted 3y ago[deleted]
- FredPret 3y agoI 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.
- ortusdux 3y agoI 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=400&pdens=2650&pdens_select=0&vel=15&theta=90&tdens=2500&tdens_select=0 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.
- H8crilA 3y agoWhere did you find the mass/size?
- ortusdux 3y agoI had to guess without albedo data, but an H of 19.2 puts it in the 0.4 to 0.5 km range, so 400m could be on the conservative side. If it randomly has an albedo of 0.05, it could be as large as 0.96km https://cneos.jpl.nasa.gov/tools/ast_size_est.html https://cneos.jpl.nasa.gov/tools/ast_size_est.html
- deleted 3y ago[deleted]
- post_break 3y agoHow long ago was it spotted. That's what I'm curious about, did we have any lead time?
- sp332 3y agoAccording to https://www.projectpluto.com/neocp2/mpecs/ZTm0038.htm#elements https://www.projectpluto.com/neocp2/mpecs/ZTm0038.htm#elemen... the observations were taken a few days ago, August 12-13. I don't know when someone calculated the future trajectory and impact probability though.
- mcint 3y ago3 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 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.
- mcint 3y agoHere's a visualization of its orbit, Earth in green, object in teal: http://orbitsimulator.com/gravitySimulatorCloud/yr/gsim2023.html?sv,1,ZTm0038,2460169.50,114739276938.995850,-91720755537.183609,-807288875.097566,18794.391969,22612.479413,1.284824,0,0,00FF00,90,65,,16000,0,12,1,0,19.575147,0.150000 http://orbitsimulator.com/gravitySimulatorCloud/yr/gsim2023....
- jacquesm 3y agoNot to spoil your lunch or anything: https://www.youtube.com/watch?v=bU1QPtOZQZU https://www.youtube.com/watch?v=bU1QPtOZQZU Of course 500 Km is a big difference with 400 meters but to those near the point of impact it wouldn't matter and the global effects would still be beyond anything in our history. This is one interpretation of what this could look like: https://youtu.be/ZyyrfB8s5cY?t=152 https://youtu.be/ZyyrfB8s5cY?t=152
- arcticpeanuts 3y agoI'm aware that it already passed its closest approach, but what does >3% even mean? 100% is >3%, but 3.000001% is >3% too. Was an impact certain at some point and the probability degraded to a bit above 3% over the course of the asteroid's trajectory? If so, I think I'd like to have a heads up when the probability is still closer to 100%, before it drops?
- abathur 3y agoThe linked page indicates: Impact probability 0.034 Edit: Not familiar with the site, but I get the sense that this probability reflects the latest run. The probability hopefully gets more accurate as observations rise? I couldn't readily figure out how to see the probability at each of the 8 observations for this one (perhaps this is the first run it's included in--all 8 observations predate this run?), but the page for actual impactors (https://newton.spacedys.com/neodys2/NEOScan/index_past_imp.html https://newton.spacedys.com/neodys2/NEOScan/index_past_imp.h...) at least implies that accuracy may improves with each (and then maybe flip to 0/100?)
- soneca 3y agoI think it specifies that it’s a 3.4% probability in the page. So it was just an odd choice of title by the poster.
- codetrotter 3y agoFrom the page: Impact probability 0.034 I guess OP decided to abbreviate to >3% instead of writing 3.4% Personally I would’ve written ~3%
- sp332 3y agoIt was 3.4% https://newton.spacedys.com/neodys2/NEOScan/risk_page/ZTm0038/index_summary_ZTm0038.html https://newton.spacedys.com/neodys2/NEOScan/risk_page/ZTm003... If you're not logged in to Twitter, I don't think you can scroll from the linked tweet up to see the one this page was linked from, so I put it here.
- arcticpeanuts 3y ago
- blurbleblurble 3y agoLooks pretty bad in this asteroid impact simulator: https://neal.fun/asteroid-launcher/ https://neal.fun/asteroid-launcher/
- ArtWomb 3y agoHow accurate is this? I just feel implicitly that a 1mi asteroid would leave a creater bigger than 30mi wide upon direct max impact ;)
- tshaddox 3y agoI also wouldn't expect an impact in rural Kansas to create a 2,500 foot tall tsunami.
- blurbleblurble 3y agoIf you scroll you'll see that the fireball is much larger than the crater.
- amiralul 3y agoDo we know how close it was?
- fghorow 3y agoAccording 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 https://www.projectpluto.com/neocp2/mpecs/ZTm0038.htm
- version_five 3y agoIs 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.
- jacquesm 3y agoIt'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.
- zardo 3y agoThat's just measure of uncertainty in out measurements, unless we're saying there was a ~3% chance someone would do an emergency asteroid redirection to make it hit.
- lucb1e 3y ago> ~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
- SoftTalker 3y ago400m 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.
- lucb1e 3y agoI 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
- rurp 3y agoIs it possible to estimate where the astroid is most likely to hit? I'm not sure how to interpret most of the info on that page.
- deleted 3y ago[deleted]
- jacquesm 3y agoLet's hope there are no 'dark companions' like with the Chelyabinsk meteor.
- mcint 3y agoHere's a visualization of its orbit, Earth in green, object in teal: http://orbitsimulator.com/gravitySimulatorCloud/yr/gsim2023.html?sv,1,ZTm0038,2460169.50,114739276938.995850,-91720755537.183609,-807288875.097566,18794.391969,22612.479413,1.284824,0,0,00FF00,90,65,,16000,0,12,1,0,19.575147,0.150000 http://orbitsimulator.com/gravitySimulatorCloud/yr/gsim2023.... It passed about 9 hours ago.
- mcint 3y agoIt was first seen on August 12, midday UT1. About a dozen observations. 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 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. I don't know what I'm talking about. Just giving best-guess interpretations.
- mcint 3y agoVSauce with packages summary for passive consumption. https://www.youtube.com/watch?v=4Wrc4fHSCpw https://www.youtube.com/watch?v=4Wrc4fHSCpw And jacquesm's replies to my other comments, https://news.ycombinator.com/item?id=37139144 https://news.ycombinator.com/item?id=37139144
- hoten 3y agoFYI VSauce is a different content creator than Veratasium (unaffiliated).
- mcint 3y agoOops, thoughtless basic error in posting something quickly. Good note.
- awb 3y ago> Since 1988 over 1,200 asteroids bigger than a meter have collided with the Earth. And of those we detected only 5 before they hit, never with more than a day of warning. Yikes
- yread 3y agoHere are some more numbers: https://www.projectpluto.com/neocp2/mpecs/ZTm0038.htm https://www.projectpluto.com/neocp2/mpecs/ZTm0038.htm In particular the MOID (Minimum Orbit Intersection Distance, the minimum distance between the orbit of the object and the Earth, in AU) is 0.0199 AU which is still 3 million km
- 23B1 3y ago[flagged]
- deleted 3y ago[deleted]
- dang 3y agoInstead of snarking and putting others down, which is against the site guidelines, why not explain something so we can all learn? If you know more than others, that's a much better way to show it. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html
- 23B1 3y agoSite guidelines also say "assume good faith". My comment is on how absurd the situation is, not a dig at any HN users.
- 1970-01-01 3y agoIndeed. We've got facts and numbers but lack an expert that can put them together in any meaningful way.
- pcrh 3y agoFrom other comments in this thread, it seems this risk has passed, but was known three days ago? Was any action taken at all? A 3% risk isn't small.
- jcul 3y agoIs there any action that could have been taken? Genuinely curious, I read about a test of some technology for deflecting asteroids a few weeks ago on HN, but I don't think we really have those capabilities yet?
- radicaldreamer 3y agoThere is likely a capability in the classified world to launch a vehicle to hit this object, but it won't be used because disclosing this ability would spark an arms race.
- macintux 3y ago“Hit” and “do something useful” would seem to be distinctly different questions. A rock that you discover just before it hits us can’t be easily deflected, and even if you destroy it all of the mass is still headed our way.
- chasd00 3y agoI don't know what action could be taken. The risk of mass anxiety and the behavior that comes with that is probably greater than any additional safety a vague 3 day warning would provide.
- dealuromanet 3y agoI would want to know, especially if it’s a large object and higher percentage probability, because then it’s a way to tell loved ones what we need to tell them and go forward together in love. We should always strive to do this, of course, but it would still be better to have the opportunity to do it.
- dheera 3y agoI'm surprised Elon Musk didn't pick up on this a couple days ago and launch something at it.
- ConanRus 3y ago[dead]
- CafeRacer 3y agoI wonder how many people already used this https://neal.fun/asteroid-launcher/ https://neal.fun/asteroid-launcher/ to see what happens if it falls in moscow downtown
- deleted 3y ago[deleted]
- gdy 3y ago[dead]
- elchief 3y agoTDB is https://en.wikipedia.org/wiki/Barycentric_Dynamical_Time https://en.wikipedia.org/wiki/Barycentric_Dynamical_Time ?
- fghorow 3y agoWhich following the contained link to Terrestrial Time (TT) states that TBD is relativity corrected TT, which itself is about 30 +/- seconds from UTC -- something much more familiar to we groundhogs...
- marcodiego 3y ago> Closest approach time of impactors: t_min = 2023/08/14 04:48 TDB and t_max = 2023/08/15 12:22 TDB If you can read this that means it hasn't hit you.
- deleted 3y ago[deleted]
- JumpinJack_Cash 3y agoThe public is unanimously in favor of funding asteroid protection mechanisms and research. It's even higher support than the military. Naturally what do we do with that money and goodwill instead? Yes! Let's build a massive space telescope which takes pictures that are only marginally better than the other multi-billion dollar space telescope! Protect the Earth? Fuck that, don't ya know kid? She's toast anyway because the Sun will explode soon! Also get in loser, we're going to Mars!
- hoten 3y agoIt seems any serious asteroid prevention program is going to require the learnings of "pointless" (as you might put it) scientific expeditions like putting an object into L2.
- jacquesm 3y agoThere have been many studies about what could be done to deal with asteroids that are on track to impact earth and the simple answer is 'nothing'. Frustrating, but unless you can think of something that none of the very clever people on those committees could think of it's going to stay that way.
- JumpinJack_Cash 3y agoThe obvious answer to that is being able to reliably detect asteroids on a collision course, and compute where is it gonna fall in order to proceed the emergency evacuation. But first you have to be able to detect it, second you have to do it with reasonable time to save as many people as possible
- jacquesm 3y agoAgain, these people aren't stupid. You will have a very large amount of uncertainty based on a series of observations which essentially project a circle of probability on the planet that shrinks as more information from newer observations comes in and then just before impact that probability will either drop to zero because it is deemed to be a near miss (sorry, George) or it will then become a certainty. By that time it will be too late to evacuate. I can dig up the report from one of these committees if you want (I should be able to find it), they make for very interesting reading, it is a really nice example of science at work, even if the result is a negative. Anything more advanced makes for great special effects in movies and science fiction but isn't going to work. You'd have a very short time to move the entire population of a circle with a radius of a few hundred kilometers to outside of that circle starting from the center. The longer you waited the fewer people you'd have to move but the bigger the chance you'd be too late.
- killthebuddha 3y agoI'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 radius? In general, I am very confused by this news because "400m diameter asteroid 3% chance of impact" is something I would expect literally everybody to be talking about all the time. It's also something where if I learned that everything north of Kansas has a 5% chance of getting hit but everything south of Houston has a 1% chance, I'd seriously consider taking an impromptu vacation.
- lijok 3y agoSpotted 3 days ago. There's an incentive not to publicize this. Lots of close passes only get coverage after the fact.
- 1970-01-01 3y agoWe need an expert to explain these facts and numbers. Until then, please buy necessary amounts of toilet paper.
- Analemma_ 3y agoWhen a new potentially-hazardous asteroid is discovered, it's normal for the probability of impact to go up a couple times before abruptly plummeting to zero, as the radius of uncertainty shrinks until it shrinks past the Earth. See https://en.wikipedia.org/wiki/Torino_scale#/media/File:Apophis_ellipse.svg https://en.wikipedia.org/wiki/Torino_scale#/media/File:Apoph.... A 3% chance of impact right after discovery with the initial error ellipse isn't all that unusual; it will almost certainly be revised to 0 with more observation (and if it's not, you'll hear about it).
- apatil 3y agoThis makes sense, thanks. However, it doesn't mean that the 3% estimate of the chance of impact was wrong at the time of initial observation given data available, and that still makes it a huge deal at that time. At minimum, it would seem to justify using the best available instruments to characterize the asteroid more precisely as soon as possible. If these large numbers happen so often that asteroids with initial impact probabilities of 3% are known to actually impact much less frequently than that, then the model is poorly calibrated, no? In other words, the reported probabilities aren't really probabilities and that is what has caused the confusion and anxiety in these comments.
- songeater 3y agodid this pass ~4000km from earth? [1] MOID given as 0.0000296 https://newton.spacedys.com/neodys2/NEOScan/risk_page/ZTm0038/index_summary_ZTm0038.html https://newton.spacedys.com/neodys2/NEOScan/risk_page/ZTm003... [2] AU to km https://www.google.com/search?q=au+to+kilomore&rlz=1C1GCEA_enUS1045US1045&oq=au+to+kilomore https://www.google.com/search?q=au+to+kilomore&rlz=1C1GCEA_e...
- fghorow 3y agoSomething weird is going on. This site [1] suggests the MOID was about 0.02 AU. [1] https://www.projectpluto.com/neocp2/mpecs/ZTm0038.htm https://www.projectpluto.com/neocp2/mpecs/ZTm0038.htm
- amiralul 3y agoOther source[1] says 0.0002 AU, still very close (about 40,000 km). [1]: https://cneos.jpl.nasa.gov/scout/object/ZTm0038 https://cneos.jpl.nasa.gov/scout/object/ZTm0038
- lucb1e 3y agoThis, as I understand it, being the closest approach to our orbit, not our atmosphere or so. To put this in perspective, the Earth is some 6.4 Mm in radius, so that's 40-6.4 = 33.6 Mm above the surface.
- lucb1e 3y agoMOID being minimum orbit intersection distance, for anyone else wondering. Sounded like someID (identifier) to me, was wondering why that value was given in AU
- pvg 3y agoMOID is an id that is just that big. You wanted more id, you got MOID.
- lucb1e 3y ago> 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.html 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?
- lijok 3y agoCan you elaborate on the question you're asking?
- lucb1e 3y agoPut differently: am I missing something if I say this website is similar in function to https://hasthelargehadroncolliderdestroyedtheworldyet.com https://hasthelargehadroncolliderdestroyedtheworldyet.com ? At least in terms of a public service announcement; I understand it's interesting for science but not so much for linking "hey look there's an X% chance of impact....yesterday!" on news websites
- NyxWulf 3y agoWhen I was taking physics at the University 20 years ago, one of my professors said that the closest we have ever come to predicting an asteroid impact was "whoa that was close" as it zipped by. Sounds like that's still state of the art.
- oskarkk 3y agoI find it very interesting even if the approach was yesterday, as the chances were seemingly quite high and asteroid was quite big. Also, Hacker News isn't exactly only news, just any interesting things, current or past.
- moonchrome 3y agoThat's what I get for reading HN before going to sleep...
- jacquesm 3y agoIf you wake up: no problem. If you don't wake up: no problem.
- lucb1e 3y ago> If you wake up: no problem Depends on what you wake up from: sirens and broken windows everywhere but not a direct hit, for instance, I wouldn't call 'no problem' :(
- jacquesm 3y agoFair enough, that would definitely be a possibility. The dashcam and other videos from Siberia are still very fresh in my mind. That was a very close call. Slightly different angle in a more populous part of the world...
- radicaldreamer 3y agoIs this the highest probability assigned to such an object?
- jacquesm 3y agoThat depends on the timescale. Over a long enough time it is 100%, for a human lifetime maybe one in a million or so.
- finite_depth 3y agoWell, no, because some have impacted Earth before. But if we limit ourselves to large bodies, yes. The current record holder is 99942 Apophis, which briefly had an estimated probability of 2.7% of an impact in 2029 (which has since been eliminated as a possibility). Apophis and ZTm0038 are around the same size. If ZTm0038 does indeed have a 3% chance of impact, it would, like Apophis, land as a 4 on the Torino scale, tying the record for the most threatening asteroid in history. Unlike Apophis, however, the impact has a lead time of hours, not decades. Efforts might have been made to deflect Apophis; no such effort could realistically be made for ZTm0038. It's worth noting that NASA's Scout page (https://cneos.jpl.nasa.gov/scout/#/object/ZTm0038 https://cneos.jpl.nasa.gov/scout/#/object/ZTm0038) for ZTm0038 has a much higher probability of impact: of their 1000 sampled orbital solutions, 160 of them impact Earth. A 16% chance of impact for a 400m asteroid would put ZTm0038 on the border of a Torino 5, and would make it by far the most threatening asteroid ever discovered. That said, note that the prior here has to be that an impact of such a size is very unlikely. Such impacts are exceedingly rare. The Tunguska event, for example, was an asteroid 1/8 the diameter (so 1/8^3 = 512 times smaller in volume) as ZTm0038, and it was by far the largest impact in recorded history. Since impacts roughly follow a power law, the much larger putative impact of ZTm0038 would be proportionately rarer, the sort of thing you'd see every hundred thousand years or so.
- lamontcg 3y agoLooks like it is about the same size as 25143 Itokawa that the Hayabusa probe visited. That has a mass of 35 billion kg. The Burj Khalifa is 0.45 billion kg so that is about 80 Burj Khalifa's.
- vkou 3y agoYes, but how many ant-sized swimming pools deep is it?
- harwoodr 3y agoPretty graphs of possible impact sites: https://twitter.com/JoelSercel/status/1691549821629526219 https://twitter.com/JoelSercel/status/1691549821629526219
- s5300 3y ago[dead]
- mazlix 3y agoThat tweet which had an image showing bands of latitude that it may hit and times (london/newyork ish tomorrow and day after) has been deleted by the author and now says "I would like to make an apology to the small body community. Some information was shared with me on an internal company message board that I did not have full perspective on and I posted a tweet, which I now understand was not appropriate. It was preliminary data and I did not have full perspective on it." I don't feel very reassured.
- pyrolistical 3y agoThis is why numbers should always be bounded. Is this 3.3-3.5%? Or 0-3.4%? Or 0-6.8%? Etc
- songeater 3y agothere seems to be a second entity on the risk list (but less than 3 observations) https://newton.spacedys.com/neodys2/NEOScan/index_risk.html https://newton.spacedys.com/neodys2/NEOScan/index_risk.html Also both these entities are "lost" but not "high priority" https://newton.spacedys.com/neodys2/NEOScan/index_nspl.html https://newton.spacedys.com/neodys2/NEOScan/index_nspl.html
- kitanata 3y ago[flagged]
- rossdavidh 3y agoOddly, I cannot find where on this page it says anything about the size of the asteroid in question. It's probably there somewhere, but I'm not seeing it somehow.
- haunter 3y agoH=19.9 ~400m diameter https://cneos.jpl.nasa.gov/tools/ast_size_est.html https://cneos.jpl.nasa.gov/tools/ast_size_est.html
- Keyframe 3y agoWhere did you get its albedo (reflectivity)?
- lucb1e 3y agoThat's in the submission, there's a column called H in the first table that says 19.90
- ortusdux 3y agoThe chart is H vs. Albedo, and is awkwardly formatted. H is the brightness observed on earth. Albedo is the inherent reflectivity of the object. What the chart is saying is that if we observe an object that is 19.5 H bright, it could either be highly reflective (0.30 albedo) and 310m across, very dim (0.05 albedo) and 760m across, or somewhere in between. As I understand it, we can only calculate the albedo if we know the size and apparent brightness. I'll note that the linked NEOscan page has an H of 19.9, while JPL's CNEOS has an H of 19.2.
- Keyframe 3y agoTrue. At least it gives us a range this way unless it's a block of ice or whatever else. I still remember some of this from rendering days. H is basically the same as M, an absolute magnitude, but for solar system objects. Difference being that for solar system objects H, as you've noted, is an absolute magnitude for an object 1 AU from Earth and 1 AU from Sun in a triangle where phase angle is zero meaning it's a straight line instead of a triangle and M is an absolute magnitude for an object (usually self illuminating) outside of solar system set at 10 parsecs from Earth. A star with M = 1 and a solar system object with H = 1 would roughly be the same brightness. It's a log scale, lower the number the brighter it is, so if you put that star at the same spot as the object it'd be a difference of about 26 where each unit is roughly 2.5 times brighter. What's interesting is that at zero it used to (roughly) be Vega (star). Both M and H are band-dependent, I guess it's V-band (visual or green-ish) if it's not mentioned. If you have B (blue) and V band, the difference between the two tells you a (visual) color which can be also interpreted as temperature, the lower the number the bluer it is and higher means red. I'm all out of trivia for the night. I'm sure there are (amateur and not) astronomers and astrophotographers here that know this stuff way more about. All I knew is that without albedo you couldn't get to the size with absolute magnitude alone, we could if we had both absolute and apparent. What I didn't know if that apparently there's a rough table of correlation between H and albedo values probably based on most rocks we've seen in space around us.
- xwdv 3y agoNot threatening, mostly harmless.
- babelfish 3y ago[flagged]
- AbrahamParangi 3y agoThis seems like it's off by ~6 orders of magnitude (see https://en.wikipedia.org/wiki/Impact_event https://en.wikipedia.org/wiki/Impact_event)
- AbrahamParangi 3y agoAmusing addendum, in order for this asteroid to have a 5Kt impact energy it would need to be traveling at around 50 mph as it impacts earth. A typical impact velocity would be something closer to 30,000 mph.
- gs17 3y agoI would recommend using a calculator designed by experts, like https://impact.ese.ic.ac.uk/ImpactEarth/ImpactEffectsMap/ https://impact.ese.ic.ac.uk/ImpactEarth/ImpactEffectsMap/ instead of ChatGPT. I get a low-end estimate of tens of megatons.
- groby_b 3y agoChatGPT also believes the moon is made out of green cheese. (Less snarky: It hallucinates an answer. It can't do math. Do not rely on ChatGPT for math. Or facts.)
- deleted 3y ago[deleted]
- jacquesm 3y agoBased 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 https://en.wikipedia.org/wiki/Chelyabinsk_meteor Was 100 times as much and was only an 18 meter asteroid.
- thatcherc 3y agoI don't really know how to read this page, but it looks like the time of closest approach has already passed - > Closest approach time of impactors: t_min = 2023/08/14 04:48 TDB and t_max = 2023/08/15 12:22 TDB If so then we're all good. Can the poster or anyone else chime in with background on this?
- SkyPuncher 3y agoI am not an expert, but my interpretation was the same as yours. TBD seems to be roughly UTC time. In which case, this passed by 8 hours ago.
- throwaway5729 3y agoI saw this tweet: https://twitter.com/ByronDrury/status/1691487518590402560?s=20 https://twitter.com/ByronDrury/status/1691487518590402560?s=... linking to https://cneos.jpl.nasa.gov/scout/#/object/ZTm0038 https://cneos.jpl.nasa.gov/scout/#/object/ZTm0038 It has some cool graphs that seem to show a lot of uncertainty in closest approach time [edited to fix second link]
- hughes 3y agoImpact time is in the past. Mission accomplished, everyone!
- nocoiner 3y agoI must have put a decimal point in the wrong place or something. I always do that. I always mess up some mundane detail.
- ortusdux 3y agoAm I reading this data correctly?: https://cneos.jpl.nasa.gov/scout/#/object/ZTm0038 https://cneos.jpl.nasa.gov/scout/#/object/ZTm0038 Because it looks like today is the most probable day of impact at 10%, but there is a good 25%+ chance it will impact sometime in the next two weeks.
- EGreg 3y agoI would also very much like to know what the consequences of an impact might be
- ortusdux 3y agoThis paper is an interesting read: https://www.sciencedirect.com/science/article/pii/S0094576517314996 https://www.sciencedirect.com/science/article/pii/S009457651... Not my area of expertise, but it sounds like a deep ocean impact would not be completely catastrophic. With only ∼1% of the asteroid kinetic energy being converted into tsunami waves and with the stronger decay with distance implies that moderate size asteroids (100–500 m in diameter) striking the deep ocean basins off the continental shelves are not a significant overall hazard... So like a 50% chance it wouldn't be that bad. Larger asteroids would vaporize enough ocean water to cause long lasting atmospheric affects. Otherwise, a land impact would be somewhere in the 1-100 Tsar Bomba range energy wise.
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