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Astronomers Calculate How To Spot Life On an Alien Earth
KentuckyFC writes: "One of the main goals of the space program is to spot an Earth-like planet orbiting another star. And by Earth-like, astronomers mean a planet with liquid water, gaseous oxygen and even chlorophyll, or a light-harvesting molecule like it. The biosignatures of these molecules were all observed during the first Earth fly-by in 1990 when the Galileo spacecraft measured the light reflected off Earth as it flew past on its way to Jupiter. But if these biosignatures exist on more distant exoplanets, could we spot them today? Now astronomers have calculated how good the next generation of space telescopes will have to be to pick up these biosignatures of life. They say that gaseous water should be relatively straightforward to pick out and that oxygen will be more challenging. But the spectral signature of chlorophyll-like molecules will be much harder to spot, requiring significantly more sensitivity than is possible today (either that or a great deal of luck). That suggests a plan, they say. The next generation of space telescopes should look for water and oxygen on exoplanets orbiting nearby stars and only then begin the time-consuming and expensive task of looking for chlorophyll on the most promising targets. One spacecraft that might do this is the Advanced Technology Large-Aperture Space Telescope or ATLAST that is currently scheduled for launch in the 2025-2035 time frame."
If a planet has life on it. If we visit it, how much damage will that cause. I mean just the bacteria on our skin that is normally helpful, my thrive and kill off all the life on the planet that may not have such defenses.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Isn't chlorophyll tuned to the easiest bands of energy that come from our sun and don't get scattered by our atmosphere? Wouldn't a slightly different stellar color or atmospheric makeup dramatically change how stellar energy would be chemically captured?
Except it's way easier to search for Water and oxygen than Chlorophyll.
Suppose it take 5 unit of time to confirm if there's oxygen
Then it take 5 unit of time to confirm if there's water vapor.
And then it take 100 unit of time to confirm if there's Chlorophyll.
You can analyze 10-20 candidates instead of just one.
And like somebody else said, Chlorophyll is one candidate, in other conditions, another chemical could be used.
It really doesn't matter. It's like that unbelievably sexy girl at the beach: you can look all you want, but since you'll never have her, why do that to yourself? With this, even if we find, water, oxygen, chlorophyll, and the unmistakable chemical signature of entire oceans filled with beer, it's irrelevant and a waste of time and money since we'll never be able to go there. Let's use this money to help undo the damage we're doing to the one little blue marble we *do* have access to and are cooking out of existence.
The intro is misleading. ATLAST has not a single dollar pledged to it. It has no "scheduled" launch date. It does have a lot of people thinking about it (and a very similar project, HDHST), but for now it exists purely in dreams and on paper.
Lifeforms... *bleep blup bleep bleep* you tiny little lifeforms... *bleep blup bleep bleep* you precious little lifeforms... *snipsnapsnap clap* where are you? *dootootootootoo bleebleeblue*
Have they read this article?
Proposed Indicator of Life On Alien Worlds May Be Bogus
(disclaimer: I haven't read either of them. Just thought it was mildly amusing to have these two articles come along within days of each other)
systemd is Roko's Basilisk.
Every time I read something like this, I wonder if any habitable planets we find will still be habitable by the time we can get to them. If we find a habitable planet just a relatively close 10 light years away, then we're already seeing it as it was 10 years ago. Something could've changed there by the time we're seeing it. It's probably unlikely there'd be THAT much change in just 10 years, but then you have to figure it'd take us thousands of years to reach it with our current technology 'cause we can't even go 1% the speed of light yet. I haven't done the math, but wouldn't that take thousands of years just to get 10 light year away? So even a habitable planet 10 light years away would be well beyond our reach for the foreseeable future.