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The Uncensored Guide to ‘Oumuamua, Aliens, and That Harvard Astronomer

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Re: The Uncensored Guide to ‘Oumuamua, Aliens, and That Harvard Astronomer

#71

Post by AnimalMuppet »

willis936 wrote: post #30
detritus wrote: post #22

Earlier quoted context omitted.

> Like comets, if one hit us it would end life on the planet. 'Oumuamua is more of a 'city-killer' risk at its size than a comet such as Halley's, which would be more of the sort of range of size that could seriously screw up our day.

True, Oumuamua itself would not have done Earth changing damage even in the worst case collision, but where there is one we have to ask “are there others?” and “how big are they?” We have a pretty good idea of the asteroids and comets in stable orbits around the sun. We know with certainty we’re not going to be hit with a planet killer asteroid in the next hundred years because we track all of them.

We track all of them that we know of. And we think that we know most of them. I'm not sure that we know all of them; I'm not sure that the trackers think that, either.

Re: The Uncensored Guide to ‘Oumuamua, Aliens, and That Harvard Astronomer

#74

Post by Itinerant662 »

Contrary to the narratives you’ll find elsewhere, including in Loeb’s new book, Extraterrestrial: The First Sign of Life Beyond Earth, this is not a possibility worth taking seriously as a scientist. A straightforward look at the evidence shows us why." -> "Loeb offers only loud, immodest speculation about aliens and diatribes about community groupthink. Coupled with inadequate data, which is the only data we have, he’s impossible to prove wrong."

Re: The Uncensored Guide to ‘Oumuamua, Aliens, and That Harvard Astronomer

#75

Post by willis936 »

AnimalMuppet wrote: post #71
willis936 wrote: post #30

Earlier quoted context omitted.

True, Oumuamua itself would not have done Earth changing damage even in the worst case collision, but where there is one we have to ask “are there others?” and “how big are they?” We have a pretty good idea of the asteroids and comets in stable orbits around the sun. We know with certainty we’re not going to be hit with a planet killer asteroid in the next hundred years because we track all of them.

We track all of them that we know of . And we think that we know most of them. I'm not sure that we know all of them; I'm not sure that the trackers think that, either.

Actually, we do. Asteroids large enough to be considered planet-killers are the easiest ones to spot.

https://youtu.be/4Wrc4fHSCpw

Re: The Uncensored Guide to ‘Oumuamua, Aliens, and That Harvard Astronomer

#76

Post by garmaine »

ericbarrett wrote: post #53
jcims wrote: post #13

Earlier quoted context omitted.

I think some of the vitriol comes around the discussion of whether or not we should develop a mission to go visit it.

There’s no chance of catching Oumuamua. It’s leaving the solar system at 26 km/s and it has a 3 year head start.

There are mission profiles that could manage a flyby on a multi-decade timeline.

Re: The Uncensored Guide to ‘Oumuamua, Aliens, and That Harvard Astronomer

#77

Post by garmaine »

Tuna-Fish wrote: post #57
jcims wrote: post #13

Earlier quoted context omitted.

I think some of the vitriol comes around the discussion of whether or not we should develop a mission to go visit it.

That's simply not practically possible. It's just going too fast. We would either have to build a really stupendously big rocket, or develop propulsion that is dramatically more efficient than anything ever done before.

Or launch a cubesat on top of a Falcon Heavy with a Vulcan Centaur kick stage and a Jupiter gravity assist.

Re: The Uncensored Guide to ‘Oumuamua, Aliens, and That Harvard Astronomer

#78

Post by andrewflnr »

nix23 wrote: post #47
andrewflnr wrote: post #24

Earlier quoted context omitted.

I think he's just implying that people have been too polite to Loeb before.

So in other articles hes censoring him self (the peoples he wants to be polite with), or has any title of him about another person the word uncensored?

It's a clickbait headline, don't overthink it.

Re: The Uncensored Guide to ‘Oumuamua, Aliens, and That Harvard Astronomer

#79

Post by bostonsre »

calibas wrote: post #44
eightails wrote: post #5

How hard is it for people to just admit that we probably have inadequate evidence to reach a solid conclusion. This was the first object of its kind and we had very limited observations of it. From what I've read, none of the hypotheses regarding the measured acceleration (e.g. outgassing vs manufactured solar sail) can really be backed up in any substantial way. So it seems disengenuous to get into vitriolic argumen…

I think it's precisely because we don't know that people have such strong opinions. People get to fill in what they want to believe, then argue a point that can never really be proven wrong or right.

Yea.. saying "I don't know" is extremely powerful and important but it doesn't seem to be said enough.

Re: The Uncensored Guide to ‘Oumuamua, Aliens, and That Harvard Astronomer

#80

Post by giantrobot »

sandworm101 wrote: post #49
giantrobot wrote: post #46

Earlier quoted context omitted.

Science money is very limited. Space science money more limited. Space science money to get components on rovers yet more limited. Telescope time is also limited. Mission time on remote probes is also limited. So you devise an experiment to measure oxygen absorption that uses a probe's existing mass spectrometer. Your experiment doesn't cut into the probe's mass budget so it basically is just a scheduling issue. If y…

>> if you propose observations of CFCs because it's a snipe hunt wasting valuable and limited instrument time. That's what they said about hot jupiters. Exoplanets could have been detected decades earlier had there not been a consistent bias against the idea of large objects orbiting so near host stars, a bias based on a single data point (our solar system).

It's unlikely many types of exoplanets could have been detected "decades" earlier. Transit and Doppler detection methods require good seeing power and accurate intensity measurements. It takes large mirrors with good optics for good seeing power and sensitive electronics for the spectral/intensity measurements. Those two things weren't readily available until the past few decades...which surprise is when exoplanet discoveries started happening.

Hot Jupiters and CFCs are very different things. Hot Jupiters were puzzling but something that could be readily detected by existing instruments. Once discovered solar system development models were improved.

CFCs in a planet's atmosphere is something current instruments can't detect. Even if they could the number of observational candidates is limited. The only way we could detect CFCs is if some civilization was actively producing them at the time that light left the planet. So even if there's millions of CFC producing civilizations in the galaxy the odds of detecting those CFCs in candidate systems is extremely low. Even if those civilizations produced CFCs for millennia the odds are against ever seeing them. So it's pretty wasteful to use valuable telescope time for that rather than something that has a higher probability of giving some results.

It's not about solar system chauvinism or biases. There's not infinite amounts of science money or science time. No one is writing off unlikely events, it's just breathless searches for those unlikely events has a huge opportunity cost. And talking about biases, assuming technological civilizations will produce CFCs is a very Earth/Human biased assumption. CFCs were/are produced on Earth for market reasons that don't necessarily apply in any circumstances except those that worked out on Earth.

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