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Four Earth-sized planets detected orbiting the nearest sun-like star

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Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#191

Post by saganus »

Balgair wrote: post #132
saganus wrote: post #105

Earlier quoted context omitted.

Isn't building a 100m telescope incredibly hard? does that kind of technology exist already? (I genuinely don't know). Also, what would the effect of the atmosphere be in such a large telescope? would a bigger mirror increase or decrease the effects of Earth's atmosphere for these kind of observations?

Noise is noise. If you put gain on the signal in general, you'll put gain on the noise too. That's why James Webb is in space and the 30 Meter Telescope (TMT) is in Hawaii, less atmosphere and clear air means less noise inputted. Still, the TMT is pretty darn good. So yes, you are correct, bigger telescope means more noise (in gestalt) while in atmosphere. THe reason bigger is better is because you can resolve smalle…

Very nice explanation. Thanks!

15 billion (as per a sibling comment) sounds like a lot, but relative to other, IMO not so important things like said plane, it's not that much.

However I wonder if it would be worth it or if that money would be better spent creating a Hubble replacement for example.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#192

Post by peatmoss »

kyberias wrote: post #119
chrismealy wrote: post #7

The fastest spacecraft ever built would take 4000 years to travel one light year.

But isn't it merely about fuel? I mean, in space you can just accelerate to most any speed significantly under light-speed just by running the engines. Right?

Believe so, but the major limiting factor is the amount of mass that you can carry to eject out the back of your ship.

The Expanse series is predicated on the development of a reactionless drive that converts energy directly into thrust without expenditure of mass. If such a technology existed, you could get going pretty fast just motoring along at a constant 1-g acceleration, and have "gravity" too.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#193

Post by gnaritas »

ExactoKnight wrote: post #183
gnaritas wrote: post #178

Earlier quoted context omitted.

> It's been nearly 100 years since anyone struggled with that in the West. You have go to be joking.

You can nitpick the exceptions, but his general point about affluent living standards existing for 100 years in the West for most people is true.

Anyone does not mean most, you may infer he meant something different but I prefer responding to what people actually say rather than what I think they meant as I'm not a mind reader and neither is anyone else and much disagreement comes from not listening to others words because you incorrectly think you know what they're trying to say. Tons of people (tens of millions) in the west continue to struggle with basic life needs, poverty is not remotely a solved problem in the west and he quite literally said it was.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#195

Post by ExactoKnight »

jerf wrote: post #109
pgwhalen wrote: post #85

Earlier quoted context omitted.

I believe he's just saying 50% of what is currently allocated for the military, so by your math, 8% of the federal budget.

And the answer is if you accomplished a miracle and cut military spending in half and freed up 8% of the federal budget, there would be a rioting mob charging towards the money... no... that doesn't really capture how much we're talking here... there would be a rioting mob charging the suddenly-available huge pile of MONEY MONEY MONEY MONEY MONEY and there's very little reason to believe space exploration would be an…

Having near certain evidence of life existing on another planet, due to seeing oxygen present in the emission spectra of an atmosphere of another planet, would be a true game changer for space probe and exploration funding.

Astronomy funding stagnates when its about rocks and geology. Bring real evidence of aliens into the mix and you've defined humanities focus for the next century.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#196

Post by WalterBright »

BigChiefSmokem wrote: post #118
WednesdayThrow1 wrote: post #110

Earlier quoted context omitted.

Maybe tech giants like Apple and Google should start using some capital to fund awesome ideas like this.

Unless they can explain to their shareholders what the benefit of that overwhelmingly long-term investment will be I don't see it happening. Maybe after SpaceX becomes a massively profitable company in the same vein as the tech giants, but not before. Bill Gates also made it painfully clear that he wants his money to go to issues we can resolve right now here on Earth like renewable energy, clean water, fighting dise…

> benefit

Easy: Marketing the brand name. Imagine a rocket with Google painted on the side on the evening news. Updates on the construction and progress, all mentioning Google. Google setting up a Google Center that collects all the data coming down. Every discovery has Google's name attached to it. Etc.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#197

Post by outericky »

jdavis703 wrote: post #162
hueving wrote: post #128

Earlier quoted context omitted.

>I am flabbergasted that as a society we aren't rushing to build a 100 metre wide telescope mirror large enough for us to directly image the spectra of the potentially habitable exoplanets around us. This is because most of society is still struggling with day-to-day tasks like getting housing, clean water, reliable food, healthcare and dealing with physical conflicts. Even people rich enough to not be stuck in the s…

Let's assume a 100-meter telescope is 10x the cost of the proposed Thirty Meter Telescope. That means it would cost about $14 billion to build. If the U.S. and E.U. split the cost it would take about $14 for every person and child to build this. If you split the cost out to a decade, it'd be about $1.40 everyone had to pay out every year. This is a matter of priorities, not there being a lack of resources.

where do I send my $56 check?

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#198

Post by ExactoKnight »

RandomedaA wrote: post #174

I feel like something similar to this is announced every year, and nothing ever comes of it.

No, something has come from it. We now have a growing massive list of habitable planets. What's lacking now is the extra tooling to study them more extensively.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#199

Post by wtvanhest »

hnau wrote: post #143
spenczar5 wrote: post #129

Earlier quoted context omitted.

Very large telescopes can achieve great resolving power, but they run up against atmospheric turbulence, particularly in many of the spectral regions we care about for checking out exoplanets. Radio light passes right through the atmosphere for the most part, which is why you see very large radio telescopes, but they're not very practical for infrared or visible light scopes. Space-based telescopes are a better avenu…

adaptive optics on earthbound telescopes have allowed them to easily surpass hubble's resolution nearly a decade ago. it's also a lot easier to service telescopes on the planet than something orbiting at the ideal L2 point, some 1.5 million km from earth.

This is extremely far from my area of expertise so I am probably wrong, but I imagine that at some point we will advance earth based telescopes to the point where we get diminishing returns when considering atmospheric disturbance.

At that point, it will make more and more sense to launch space based telescopes. But... if we wait until we reach that point in the diminishing returns curve, than we lost valuable innovation time/expertise in space based technology.

My hunch is that if we wanted to get the best telescope tech in any given period of time, we should do both and watch as the two types of technologies converge.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#200

Post by andrepd »

ExactoKnight wrote: post #101

I am flabbergasted that as a society we aren't rushing to build a 100 metre wide telescope mirror large enough for us to directly image the spectra of the potentially habitable exoplanets around us. A telescope this large could tell us whether any of these potentially habitable planets contain oxygen, and thus, biological processes. Yet thanks to funding cuts in science the biggest telescope we have in the pipeline r…

Putting it bluntly: I'm not flabbergasted because I don't live in a bubble. The great majority of people in this planet have more pressing things to worry about than a 100 metre telescope, things like housing, having food for tomorrow, money, not getting killed, not getting raped, not getting exploited by rich oligarchs/the government, etc etc.

Man, I too wish we had more money for large scale scientific endeavours, but I am not flabbergasted that we don't; I can see perfectly why not.

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