May 10, 2017

Re-thinking the search for life on Mars

This image from NASA's Mars Reconnaissance Orbiter (MRO) shows the location with the most impressive known gully activity in Mars' northern hemisphere. / NASA

Scientists are re-thinking how to go about finding life on Mars, per a Scientific American dispatch from a recent conference of astrobiologists, geologists and others.

Key takeaways:

  • Maybe we don't have to find life in water. Here on Earth, there are organisms that can survive without water for years and come back to life when conditions are wetter.
  • We may have to drill into Mars to find evidence of past life. Yesterday, astrobiologists reported finding fossils of primitive microbes on Earth in what is today a hot, dry region of Australia that once had hot springs. Mars could have had the same environment in its past.
  • Microorganisms may have traveled between Mars and Earth on meteorites. Robert Hazen told me yesterday it is entirely plausible that life could have arrived here from Mars but, given the Sun's gravitational pull, it is unlikely it traveled the other direction.

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George Zimmerman sues Buttigieg and Warren for $265M

George Zimmerman in Sanford, Florida, in November 2013. Photo: Joe Burbank-Pool/Getty Images

George Zimmerman filed a lawsuit in Polk County, Fla. seeking $265 million in damages from Democratic presidential candidates Pete Buttigieg and Elizabeth Warren, accusing them of defaming him to "garner votes in the black community."

Context: Neither the Massachusetts senator nor the former Southbend mayor tweeted his name in the Feb. 5 posts on what would've been the 25th birthday of Trayvon Martin, the unarmed black teen Zimmerman fatally shot in 2012. But Zimmerman alleges they "acted with actual malice" to defame him.

4 takeaways from the Nevada Democratic debate

Photo: Mario Tama/Getty Images

The relative civility of the last eight Democratic debates was thrown by the wayside Wednesday night, the first debate to feature the billionaire "boogeyman," Michael Bloomberg, whose massive advertising buys and polling surge have drawn the ire of the entire field.

The big picture: Pete Buttigieg captured the state of the race early on, noting that after Super Tuesday, the "two most polarizing figures on this stage" — Bloomberg and democratic socialist Bernie Sanders — could be the only ones left competing for the nomination. The rest of candidates fought to stop that momentum.

Klobuchar squares off with Buttigieg on immigration

Buttigieg and Klobuchar in Las Vegas on Feb. 19. Photo: Mario Tama/Getty Images

Former South Bend, Ind., Mayor Pete Buttigieg went after Sen. Amy Klobuchar on the debate stage Wednesday for voting to confirm Customs and Border Protection Commissioner Kevin McAleenan and voting in 2007 to make English the national language.

What she's saying: "I wish everyone was as perfect as you, Pete, but let me tell you what it's like to be in the arena. ... I did not one bit agree with these draconian policies to separate kids from their parents, and in my first 100 days, I would immediately change that."