A study of molecules in the fossil record has pinpointed the rise of algae on Earth:
A planetary takeover by ocean-dwelling algae 650 million years ago was the kick that transformed life on Earth. That's what geochemists argue in Nature this week [DOI: 10.1038/nature23457] [DX], on the basis of invisibly small traces of biomolecules dug up from beneath the Australian desert.
The molecules mark an explosion in the quantity of algae in the oceans. This in turn fuelled a change in the food web that allowed the first microscopic animals to evolve, the authors suggest. "This is one the most profound ecological and evolutionary transitions in Earth's history," lead researcher Jochen Brocks told the BBC's Science in Action programme.
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Algae Terraformed Earth 650 Million Years Ago
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(Score: 0) by Anonymous Coward on Friday August 18 2017, @01:37PM (1 child)
Isn't this a variation on, "Which came first, the chicken or the egg?"
At least now we know that the chicken & egg used to be dinosaurs...
(Score: 2) by bzipitidoo on Friday August 18 2017, @10:24PM
Sounds more like a variation on Snowball Earth, a name for the 2 or 3 times the entire world was covered in ice. I suppose this would be Pond Scum Earth.
(Score: 1, Informative) by Anonymous Coward on Friday August 18 2017, @03:45PM (2 children)
This is not new. It is stage 2 in the Great Oxidation Event.
https://en.wikipedia.org/wiki/Great_Oxygenation_Event [wikipedia.org]
What is not mentioned: the seas were opaque/green due
to dissolved iron. As O2 rose, it oxidized & precipitated to
the bottom, & the seas cleared. Meanwhile, UV went down
due to formation of an ozome layer.
(Score: 3, Informative) by Anonymous Coward on Friday August 18 2017, @04:50PM
Pretty sure this is a different thing, the O2 catastrophe happened 2.5–2.4 billion years ago according to wikipedia.
This event is much more recent.
(Score: 1) by khallow on Saturday August 19 2017, @12:07AM
(Score: 3, Insightful) by Runaway1956 on Friday August 18 2017, @03:59PM (7 children)
Terraforming exoplanets will take some time. Bring some good books along.
(Score: 2) by frojack on Friday August 18 2017, @05:48PM (6 children)
But a lot of dreamers, even here on SN, seem to handwaive terraforming into existence, especially here at "home in our back yard on mars". Its a done deal as far as these folks are concerned.
You can identify these types because words like "gravity well" and "mine the asteroid belt" seem to be the first thing out of their mouths.
We just had a story about an exoplanet 16 light years away. Some have their bags packed already.
No, you are mistaken. I've always had this sig.
(Score: 2) by bob_super on Friday August 18 2017, @05:58PM
There's plenty of reason to be confident in the upcoming progress of terraforming techniques, considering how dedicated some people are at trashing the place.
(Score: 3, Interesting) by takyon on Friday August 18 2017, @06:17PM (2 children)
Smaller scale projects may be more feasible. Such as an enclosed dome somewhere or a floating city on Venus.
Mars, the Moon, Titan, and Venus all seem like top targets. The Moon has proximity. Mars has decent gravity. Venus has Earth-like gravity and possible Earth atmosphere like conditions high up. Titan has a much thicker atmosphere than Mars (no "rocket cranes" needed to land, less pressure/vacuum issues, and aerial flight + drones can be used). Honorable Mention to Ganymede which has less gravity than the Moon due to its icy lower density, more gravity than Titan, and lots of water and surface area. The radiation environment is not as bad as Europa since it is further away from Jupiter and has a magnetosphere.
This wiki has some interesting info (doesn't make it any less implausible):
http://terraforming.wikia.com/wiki/Special:AllPages [wikia.com]
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by realDonaldTrump on Friday August 18 2017, @11:18PM (1 child)
Terraforming makes it inhabitable, right? I'd start with Venezuela. Then Detroit. 🇺🇸
(Score: 3, Touché) by takyon on Friday August 18 2017, @11:30PM
And now that Steve Bannon's gone [thehill.com], there's nobody to stop you from
foreign interventionterraforming (aka TERRAFORN™)!I'll help you out by adding U+1F1FA and U+1F1F8 to the next version of my extension, Mr. President. 🇺🇬
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by Runaway1956 on Friday August 18 2017, @11:57PM
Well, to be fair, with intelligent design and guidance, with definite goals in mind, terraforming can be speeded up by orders of magnitude. That is, there is no need to wait around for random genetic mutations to kick start specific terraforming goals.
Still, even if (and that's a big if) we know what we have, and what we want, and how to get there, it's going to take thousands if not tens of thousands of years to make an almost-habitable planet habitable. And, that assumes almost unlimited resources to work with.
When terraforming is used in a SciFi story, that alone indicates how much science the authors understands. That is one reason I like the 'Expanse' series. Terraforming Mars is a distant, generational goal. Later in the series, terraforming is again approached rationally. None of us has the knowledge to say that those authors got it "right", but they are more "right" than most authors.
(Score: 1) by khallow on Saturday August 19 2017, @12:19AM
This "dreaming" is not in a vacuum. For example, over the past 6000 years we've gone from very little farming, concentrated in unusually productive areas to a ninth of the world's land surface with pastoral lands taking up twice that amount. In other words, a third of the Earth's surface has been terraformed to grow food.
The land area of Earth also happens to be roughly the same as the surface area of Mars. So we are seeing transforming of the Earth's surface on a scale that would be analogous, though obviously less difficult, than the transforming of the surface of Mars. The point here is that we have an example of terraforming in practice.