December 8, 2014

NASA scientists announced Monday that the mountain explored by the Curiosity Rover may have once been a lake.

The rover landed on Mars in 2012 in the Gale Crater, which is 96 miles in diameter and was formed by an asteroid impact. Scientists have used the rover to investigate Mars and Mount Sharp, a three-mile-high mountain of debris in the middle of the Gale Crater. They believe the layered mountain formed billions of years ago.

Scientists have long wondered about the environment of ancient Mars and why a mountain was in the center of a barren crater. Now, rock images suggest that Mount Sharp formed in a lake bed over millions of years, and the mountain was shaped by sediment deposits. The rover found evidence of lake deposits in the crater, which could mean that Mars' warm, wet period was more recent than scientists previously thought.

"During wet periods, water pooled in lakes where sediments settled out in the center of crater," NASA told Discovery News. "Even during dry periods in the crater center, groundwater would have existed beneath the surface. Then, during the next wet period it would resurface to form the next lake. This alternation of lakes, rivers and deserts could have represented a long-lasting habitable environment."

The scientists are unsure whether microbial life was present in the lake, but Michael Meyer, the lead scientist behind NASA's Mars exploration program, told The Associated Press that the lake had "sufficient time for life to get started and thrive." Meghan DeMaria

8:23 a.m. ET

A significant chunk of North Korea's 550-person delegation to the 2018 Winter Olympics will be members of the nation's "cheering squad," The Associated Press reported Wednesday. Some 230 North Koreans are reportedly traveling to Pyeongchang, South Korea, for the express purpose of root root rooting for the home team, a move Japan has dismissed as being nothing more than a "charm offensive," Reuters writes.

North and South Korea agreed earlier this month for the North to send a symbolic delegation to the Olympics, including the cheer team and a 140-member art troupe. On Wednesday, South Korea confirmed that the two technically warring nations will march together during the opening ceremony under a unified Korean Peninsula flag. South Korea is additionally appealing to the Olympic committee to allow for its women's hockey team roster to be expanded so North Korean players can join, a move that could potentially lead to the Koreas' first unified competitive Olympic team.

Japanese Foreign Minister Taro Kono wrote off the symbolic moves, claiming that "it is not the time to ease pressure, or to reward North Korea." Kono added, "The fact that North Korea is engaging in dialogue could be interpreted as proof that the sanctions are working." Learn more about the North Korean cheerleading team below. Jeva Lange

8:20 a.m. ET

Bitcoin plunged by 25 percent to a six-week low early Wednesday due to growing fears of a regulatory crackdown in South Korea. The cryptocurrency briefly dropped below $10,000. Rival cryptocurrencies also plummeted, some by even greater percentages than bitcoin. South Korea has walked back a vow to ban sales of Bitcoin, but the country's finance minister, Kim Dong-yeon, said "the shutdown of virtual currency exchanges is still one of the options" open to the government. Reports last week said South Korea was working on discouraging speculative cryptocurrency trading behind their meteoric rise this year. South Korea said it wouldn't make a move until it had time for "sufficient consultation and coordination of opinions." Harold Maass

7:49 a.m. ET

Immigration and Customs Enforcement agents are reportedly poised to arrest more than 1,500 undocumented immigrants in the region around the Bay Area in California in a maneuver apparently intended to send a signal to sanctuary cities across the country, the San Francisco Chronicle reports.

Gov. Jerry Brown (D) signed statewide sanctuary legislation for California in October, leading acting ICE Director Thomas Homan to tell Fox News that the state "better hold on tight." The upcoming sweep will target "people who have been identified as targets for deportation, including those who have been served with final deportation orders and those with criminal histories," the Chronicle reports based on conversations with someone familiar with ICE's plans, although "the number could tick up if officers come across other undocumented immigrants in the course of their actions and make what are known as collateral arrests."

California Sen. Dianne Feinstein (D) responded to the news Tuesday, blasting the administration for "carrying out its enforcement actions to make a political point and not based on the security of the country." Santa Clara University School of Law professor Pratheepan Gulasekaram, who specializes in immigration, told the Chronicle the raid is likely to "tear up a lot of lives" but won't have a "meaningful outcome on public safety."

On Tuesday, Homeland Security Secretary Kirstjen Nielsen said that the Justice Department is also considering hitting local leaders who implement sanctuary city laws with criminal charges, Newsweek reports. Homan had also told Fox News: "We gotta take [sanctuary cities] to court, and we gotta start charging some of these politicians with crimes." Jeva Lange

6:36 a.m. ET

On Tuesday, the Justice Department said it would take the unusual step of asking the Supreme Court to step in and overturn U.S. District Judge William Alsup's ruling blocking President Trump's decision to wind down the Deferred Action on Childhood Arrivals (DACA) immigration program, bypassing the U.S. 9th Circuit Court of Appeals. "It defies both law and common sense" that a "single district court in San Francisco" can halt Trump's plan, Attorney General Jeff Sessions said in a statement. "We are now taking the rare step of requesting direct review on the merits of this injunction by the Supreme Court so that this issue may be resolved quickly and fairly for all the parties involved."

California Attorney General Xavier Becerra (D), who filed one of the federal lawsuits that led to Alsup's injunction, said he was confident that higher courts will uphold the decision to block "the unlawful action by the Trump Administration to terminate DACA." The fate of the roughly 700,000 DREAMers covered by DACA is a central sticking point in negotiations to fund the federal government. The Justice Department isn't requesting a stay of Alsup's ruling, The Washington Post notes, and as soon as it files its petition with the Supreme Court, the justices can take the case or wait for the 9th Circuit appellate court to weigh in first, as would normally happen. Peter Weber

6:05 a.m. ET

Residents of Detroit and elsewhere in southeast Michigan saw a bright flash at about 8:15 p.m. on Tuesday, followed by an earth-shaking boom, and meteorologists pretty quickly said thunder and lightening weren't to blame. People who got a good look at the bright light arcing across the night sky would have likely already ruled out lightening. A Michigander named Mike Austin posted this dash-cam recording of what the U.S. Geological Survey eventually confirmed to be a meteor that caused a magnitude 2.0 earthquake.

A meteor blazing across the sky is "certainly a rare occurrence," National Weather Service meteorologist Jordan Dale told the Detroit Free Press. Some people who saw the flash, visible from Flint to Toledo, were concerned, but others saw the lighter side. Luckily, as one wag joked darkly, the meteor didn't fall on Hawaii. Peter Weber

5:23 a.m. ET
Alex Edelman/AFP/Getty Images)

Senate Democrats said Tuesday that they have 50 votes for a measure to restore net neutrality rules overturned by the Republican majority on the Federal Communications Commission (FCC), putting them one vote shy of being able to force the measure. But even if House Speaker Paul Ryan allowed a vote on the measure and it passed, President Trump would likely veto it, despite net neutrality's broad popularity. So Tuesday also saw a handful of federal lawsuits filed to block the FCC's net neutrality repeal.

One suit was filed by the attorneys general of 21 states and Washington, D.C., all of them Democrats, arguing that the FCC's "arbitrary and capricious" decision violated federal law and the FCC's longstanding policy of preventing internet service providers from blocking or throttling websites. "The repeal of net neutrality would turn internet service providers into gatekeepers — allowing them to put profits over consumers while controlling what we see, what we do, and what we say online," said New York Attorney General Eric Schneiderman. The Mozilla Foundation, the Open Technology Institute, and the public interest groups Free Press and Public Knowledge also filed separate lawsuits.

The 2015 rule giving the FCC teeth to enforce net neutrality, like previous net neutrality rules, was challenged in court by telecom firms, and a federal appellate court sided with the FCC in that case. Broadband companies are now siding with the FCC while the Internet Association, a trade group that includes Google and Netflix, is backing the net neutrality side. The FCC said its December rule stipulated that its net neutrality repeal couldn't be challenged until it was logged in the Federal Registry, so Tuesday's lawsuits were preliminary moves to determine which court will hear this round of legal challenges. Peter Weber

4:31 a.m. ET

White House physician Dr. Ronny Jackson gave a rare press conference Tuesday to describe President Trump's annual physical, and it looks like we owe Trump's personal physician an apology for doubting that Trump is in excellent health, Trevor Noah said on Tuesday's Daily Show. "No heart problems, no dementia, no dentures — but did you test for racism?" he asked. "It turns out, according to the official White House doctor, Trump is completely sane. Which makes me more worried, because that means he's doing all of this s--t on purpose? You 'covfefe' in your normal mind?"

"To us, the non-experts, the only thing that looks healthy about Donald Trump is that he's shaped like a food pyramid," Noah said. "To say that his health is excellent, it's like medicine is gaslighting us now." But Jackson had an explanation: good genes. "Look, to be honest, I'm not really surprised," Noah said. "Donald Trump has dictator blood. We're used to this in Africa and other places in the world: Castro, Mugabe, the queen — we're all shocked at how long they live." He imagined the talk Trump will give to the cockroaches after the nuclear apocalypse.

On The Late Show, Stephen Colbert was impressed with Jackson's diagnosis of Trump's cardio health. "So despite all evidence, Donald Trump does have a heart," he joked. And, according to the federal body mass index, he's one pound shy of being obese. "One pound?" Colbert asked, tiptoeing toward "girtherism." "That's awfully convenient."

Jackson "says he has no concern about the president's cognitive ability — which makes one of us," Jimmy Kimmel marveled on Kimmel Live, "and despite the fact that he is borderline obese, Trump is in excellent health. How can he be in excellent health? When he sneezes, gravy comes out...." He ended with a re-enactment of Jackson's press conference, only with a horror-like twist at the end inspired by Trump's anti-baldness medication. Watch below. Peter Weber

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