Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Vera C. Rubin Observatory first images

rubinobservatory.org

Post reply on HN
Print view View original

151–160 of 172 posts

Re: Vera C. Rubin Observatory first images

#151

Post by adgjlsfhk1 »

NitpickLawyer wrote: post #89
_alternator_ wrote: post #67

Earlier quoted context omitted.

Spy sats are more bandwidth and power constrained. For low earth, you also can’t usually offload data over the target.

> For low earth, you also can’t usually offload data over the target. That capability is coming with starlink laser modules. They've already tested this on a dragon mission, and they have the links working between some satellite shells. So you'd be able to offload data from pretty much everywhere starlink has presence.

Vera Ruben is producing ~4gbps constantly. just dealing with the heat to send that much data is highly nontrivial.

Re: Vera C. Rubin Observatory first images

#152

Post by adgjlsfhk1 »

throw0101c wrote: post #74

PetaPixel has a decent article / video on the topic from a visit to the observatory: * https://petapixel.com/2025/06/23/hands-on-at-the-vera-c-rubi... Not super technical, but a little higher level (with decent analogies to photography, for their traditional audience).

I really like that they mentioned how the telescope will be sub-optimal for wedding photography

Re: Vera C. Rubin Observatory first images

#153

Post by padjo »

matheusd wrote: post #136
padjo wrote: post #121

Earlier quoted context omitted.

It seems incredibly bizarre to assign a monetary value to the elimination of all human life given the concept of monetary value would be wiped out along with the people.

The counterpoint is that not doing so (implying some sort of infinite monetary loss if the entire human species is wiped out) would mean you want to spend every single unit of monetary value of the entire global economy to preventing this (which is also obviously nonsense - people have to eat after all). So you have to put the monetary value somewhere (although you're completely within your right to question this spe…

I think what I’m trying to express is that it feels like the answer isn’t any amount of money, it’s just undefined, like a division by zero or trying to read the value of a binary register on a machine that’s turned off. I think Pirsig called it a Mu answer.

Re: Vera C. Rubin Observatory first images

#154

Post by myrmidon »

cogman10 wrote: post #145
myrmidon wrote: post #113

Earlier quoted context omitted.

I don't believe that this would change the outcome much: It seems hard to argue that preservation of a nonhuman species would be worth more than a million lives (=> negligible) and assuming global loss of all human life is already unreasonably pessimistic in my view-- (e.g. the Chicxulub impactor would not have achieved this). I also think that fully accounting for multi-generational consequences is murky/questionabl…

I think where the calculations are breaking down is in the probability of asteroid strikes. All the math assumes that the probabilities will follow historic trends and is relatively static. With single digit events, we really have no way in knowing what the actual likelihood of impact is. It could be 1 in 100 million, it could actually be 1 in 1 million and we've been rolling a bunch of nat 20s. Before we build out t…

I agree that detection is a very helpful first step and almost enough on its own. But I'm unsure how far this can be pushed-- I think impact certainty for a century or more might be physically impossible, because of uncertainty in orbital parameters and chaotic behavior of the whole system.

I also believe the approximate bounds we have on impact probability are good enough for this estimate and quite unlikely to be off by a factor of 100, because we can guess at both size distribution and impact likelihood from craters (on earth and moon), and if the >10km object impact likelihood was over 1/million years we would expect to see a hundred times more craters of the corresponding size...

Re: Vera C. Rubin Observatory first images

#155

Post by legohead »

binarystargazer wrote: post #126

I'm the Rubin team member responsible for mapping the data into RGB images. I have been a long time reader of hacker news, but finally made an account to comment on this. I wanted to thank everyone here for their interest and taking their time to check out these images. Seeing everyone interested and engaged makes all the long hours worth it.

Thank you for your work!

Re: Vera C. Rubin Observatory first images

#156

Post by prpl »

prpl wrote: post #71
dekhn wrote: post #8

I really like the Rubin because I think a lot of people focus too much on "deep" seeing (IE, looking at individual or several objects with very high magnification only once). The Rubin does much more "wide" seeing and this actually produces a ton of useful data- basically, enough data to collect reliable statistics about things. This helps refine cosmological models in ways that smaller individual observations cannot…

It does wide through image stacking/repeated visits. The speed and FOV is the key here.

Too late to edit - I meant Deep.

Re: Vera C. Rubin Observatory first images

#157

Post by trhway »

komali2 wrote: post #140
o11c wrote: post #84

Earlier quoted context omitted.

Note that it makes a lot of assumptions beyond the stated ones, such as: * the only objects in space are stars * all stars are equally bright * the average brightness is one that can be seen (unless you roll all this into "homogeneous"?)

Yeah I'm confused because couldn't a black hole between us and a star be the reason for a black spot? That times a bajillion for whatever else is out there.

gravitational lensing would make the light go around the black hole.

Re: Vera C. Rubin Observatory first images

#158

Post by myrmidon »

adgjlsfhk1 wrote: post #148
myrmidon wrote: post #98

Earlier quoted context omitted.

These numbers are not what I expected at all. So you could actually make an argument that to a country like the US, full 100% reliable asteroid protection is only worth like $50M/year (even if an impact means full extinction)? So if upkeep for a detection/deflection system costs more than that we'd be "better off" just risking it?! Thats insane. I would have expected this number to be much higher than $50M/year.

one thing this analysis is missing is the smaller asteroids. for every planet altering asteroid, there are hundreds that could cause a tsunami that would wipe out a few cities

Good point, but I think those are "worth" less from a risk-analysis PoV: 1km diameter is apparently about 200 times more likely (1/500000 years) according to wiki, but would need to kill 40M people to match the extinction-level asteroid risk (so basically-- unmitigated hit on Tokyo or bust).

To be honest, I think the 1km diameter range might still be a major fraction of the actual risk, because the estimates around "human exctinction every 100Ma" are probably much too pessimistic.

Re: Vera C. Rubin Observatory first images

#159

Post by mapt »

cogman10 wrote: post #145
myrmidon wrote: post #113

Earlier quoted context omitted.

I don't believe that this would change the outcome much: It seems hard to argue that preservation of a nonhuman species would be worth more than a million lives (=> negligible) and assuming global loss of all human life is already unreasonably pessimistic in my view-- (e.g. the Chicxulub impactor would not have achieved this). I also think that fully accounting for multi-generational consequences is murky/questionabl…

I think where the calculations are breaking down is in the probability of asteroid strikes. All the math assumes that the probabilities will follow historic trends and is relatively static. With single digit events, we really have no way in knowing what the actual likelihood of impact is. It could be 1 in 100 million, it could actually be 1 in 1 million and we've been rolling a bunch of nat 20s. Before we build out t…

While I'm strongly supportive of survey astronomy in general...

We can already say that we have very high completion of cataloguing near-Earth objects that are anywhere near extinction-event / Chicxulub-sized (~10km), and have a majority of catastrophic / country-killer (~1km), and are digging deeper and deeper into regional / city-killer (~100m) bodies.

What we don't have is comets. Comets on long period orbits just aren't readily detectable with this sort of survey unless they're quite close in to the Sun, and I don't think we have great statistics on frequency vs size, size being something that requires very specific radar cross-checking to establish with any confidence. A long-period comet or hyperbolic body has a potential impact velocity much higher than inner system asteroids, and impact energy scales with impact velocity squared.

Re: Vera C. Rubin Observatory first images

#160

Post by cogman10 »

myrmidon wrote: post #154
cogman10 wrote: post #145

Earlier quoted context omitted.

I think where the calculations are breaking down is in the probability of asteroid strikes. All the math assumes that the probabilities will follow historic trends and is relatively static. With single digit events, we really have no way in knowing what the actual likelihood of impact is. It could be 1 in 100 million, it could actually be 1 in 1 million and we've been rolling a bunch of nat 20s. Before we build out t…

I agree that detection is a very helpful first step and almost enough on its own. But I'm unsure how far this can be pushed-- I think impact certainty for a century or more might be physically impossible, because of uncertainty in orbital parameters and chaotic behavior of the whole system. I also believe the approximate bounds we have on impact probability are good enough for this estimate and quite unlikely to be o…

> I think impact certainty for a century or more might be physically impossible, because of uncertainty in orbital parameters and chaotic behavior of the whole system.

We already have 10s of years of certainty with the current observations. Most of the uncertainty comes from the interactions of unknown objects. As the mappings of objects increase, our predictions will become much better.

The other thing to consider is that large objects will have much better certainty. A 10km asteroid won't be influenced (much) by colliding with 100 1m asteroids. It will only be impacted if it hits or swings by something like a 1km asteroid.

Rubin should in a pretty short timeframe (a few years) give us an orbital mapping of all the >1km asteroids, which is pretty exciting.

Post reply on HN