Facebook founder and CEO Mark Zuckerberg told CNN on Wednesday he's "really sorry" about a data breach that affected an estimated 50 million Facebook users, acknowledging that the company has "a basic responsibility" to protect people's information, "and if we can't do that then we don't deserve to have the opportunity to serve people."

The company is under scrutiny following the revelation that a data scientist created a personality quiz that was taken by millions of Facebook users, and their personal information and that of their friends was then secretly passed along to the data analytics firm Cambridge Analytica. Zuckerberg told CNN's Laurie Segall that "anyone whose data may have been affected" will be notified by Facebook, and the platform plans on building a tool that lets users see if their information has been compromised and if they are using any apps that are "doing sketchy things."

Zuckerberg said he's "not sure we shouldn't be regulated," as there are "things like ad transparency regulation that I would love to see." He's also "sure someone's trying" to use Facebook to meddle in the 2018 midterm elections, a "Version 2 of whatever the Russian effort was in 2016," and "there are going to be some new tactics that we need to make sure that we observe and get in front of." Zuckerberg would be "happy" to testify before Congress "if it's the right thing to do," he said, and when Segall asked if, knowing what he does now, he thinks "Facebook impacted the results of the 2016 election," he gave a vague response. "Oh that's — that is hard," Zuckerberg said. "You know, I think that it is — it's really hard for me to have a full assessment of that." Catherine Garcia

Jim Lehrer, the longtime anchor of PBS NewsHour who moderated more presidential debates than anyone else, has died at 85.

Judy Woodruff, managing editor of PBS NewsHour, said in a press release that the beloved journalist died "peacefully in his sleep at home" on Thursday.

"I'm heartbroken at the loss of someone who was central to my professional life, a mentor to me and someone whose friendship I've cherished for decades," Woodruff said. "I've looked up to him as the standard for fair, probing and thoughtful journalism and I know countless others who feel the same way."

PBS President Paula Kerger said the network is "deeply saddened" by Lehrer's death, noting that he "exemplified excellence in journalism throughout his extraordinary career." Lehrer served as PBS anchor for 36 years, founding PBS NewsHour with Robert MacNeil. He also moderated 12 presidential debates, which PBS notes in its press release is the most of anyone in U.S. history, and wrote numerous novels, memoirs, and plays.

Journalists paid tribute to Leher on Thursday, with CNN's Jake Tapper remembering him as a "wonderful man and superb journalist," Fox News' Bret Baier calling him "one of the best debate moderators and an inspiration to a whole generation of political journalists — including this one," and The Washington Post's Robert Costa writing, "I will miss him, particularly the love of country and politics he brought to everything he did." Brendan Morrow

Apocalyptic doom is apparently closer than it's ever been before.

Every year, the Bulletin of the Atomic Scientists announces the world's status on its "doomsday clock," which reveals just how close all of humanity is to certain destruction. And after putting it at a dangerous two minutes from apocalypse for the last few years in a row, scientists upped their prediction to an unprecedented 100 seconds on Thursday.

The greatest threats to humanity, as outlined by the Bulletin, are "nuclear war and climate change," which are "compounded by a threat multiplier — cyber-enabled information warfare — that undercuts society's ability to respond." The scientists specifically called out how 2019 saw the end of "several major arms control treaties and negotiations," while "political conflicts regarding nuclear programs in Iran and North Korea remain unresolved and are, if anything, worsening."

As for climate change, scientists acknowledged "public awareness of the climate crisis grew over the course of 2019, largely because of mass protests by young people around the world." But "government action" hasn't risen to meet that public push, and even the UN has "put forward few concrete plans to further limit the carbon dioxide emissions," the statement continued. Altogether, this puts the world closer to a metaphorical midnight than ever before in the clock's 73-year history. Kathryn Krawczyk

Actress Annabella Sciorra took the stand in Harvey Weinstein's criminal trial Thursday, providing harrowing testimony alleging the disgraced producer raped her.

Sciorra was called as a witness in the New York trial, in which Weinstein is facing sexual assault and rape charges. The Sopranos actress told jurors that in 1993 or 1994, Weinstein raped her in her New York apartment after a dinner, pushing the door open after he dropped her off, per The Hollywood Reporter. She previously spoke with The New Yorker about her allegation.

"He kept coming at me, and I felt very overpowered because he was very big," she testified. "...As I was trying to get him off of me — I was punching him, I was kicking him — and he took my hands and put them over my head. He put my hands over my head to hold them back, and he got on top of me and he raped me."

Sciorra, who The New York Times reports was "fighting back tears" as she testified, went on to say that she couldn't fight Weinstein off "because he had my hands locked." She said she didn't call the police and tried to pretend "it never happened" but that she "began to drink a lot" and "began to cut myself." Weeks later, Sciorra said she confronted Weinstein and he told her in a "very menacing" and "threatening" way, "This remains between you and I."

Weinstein lawyer Damon Cheronis cast doubt on Sciorra's account, saying "we can't interview neighbors to figure out what happened" because she can't recall the exact date the encounter took place, per the Times.

Prosecutors in Weinstein's case allege he forcibly performed oral sex on a woman in 2006 and raped a woman in 2013, although additional witnesses will testify as prosecutors seek to establish a pattern of behavior. Weinstein has pleaded not guilty and has denied allegations of non-consensual sex. If convicted, he faces possible life in prison. Brendan Morrow

San Francisco Mayor London Breed has officially switched her 2020 allegiances.

Previously a supporter of Sen. Kamala Harris (D-Calif.) before she dropped out late last year, Breed announced Thursday she would endorse former New York City Mayor Michael Bloomberg for president. "He has the ability to beat Donald Trump this November, and that is of the most concern to me," Breed, who was elected in a ranked-choice vote in 2018, said.

While she "thought long and hard" before making her decision, Breed said Bloomberg's "track record of what he's done as New York City mayor and what he's done afterward has been significant." Breed will start advising Bloomberg on homelessness and housing and climate change, she said, noting Bloomberg has used his wealth to "improve the climate and the quality of life in other communities."

One of the candidates Breed beat out was Jane Kim, who's now a regional director for Sen. Bernie Sanders' (I-Vt.) 2020 campaign. Breed was considered more of a moderate in that race, making her the latest addition to Bloomberg's slate of moderate mayoral supporters that includes the leaders of Louisville, Kentucky; Memphis, Tennessee; Philadelphia; and San Jose, California.

Still, former South Bend, Indiana, Mayor Pete Buttigieg is dominating the mayoral endorsement market in terms of sheer numbers. He's got some big-city backers in the mayor of Austin, Texas and a former mayor of Houston, but mostly excels in rounding up support from mid-size and smaller cities. Kathryn Krawczyk

Marianne Williamson is looking for a Democratic candidate who can give us all a good "chuckle," and she knows just the one to do it.

Williamson, the author and self-help guru who ended her 2020 campaign earlier this month, announced on Instagram this week she's backing Andrew Yang in the Iowa caucuses.

In the post, Williamson praised Yang's "self-confidence, levity, and positivity," writing these qualities are "every bit as important" as his stance on the issues because "we will beat [President Trump] by forging an emotional connection with the American people that is more compelling than his."

She went on to praise Yang for "taking us back to a more innocent time, making us remember to chuckle ... This is not an unserious issue at all, for that chuckle has more power to take us over the line in 2020 than does all the anger in the world. Quite simply, the demon doesn't know how to eat it."

While Williamson said she admires both Sens. Elizabeth Warren (D-Mass.) and Bernie Sanders (I-Vt.), she's backing Yang to "hopefully to help him get past the early primaries" so he can "remind us not to take ourselves too seriously," as "we need to lighten up on a personal level."

Williamson did make clear in her post she isn't offering an official endorsement here, only saying Yang is who she's backing in Iowa. Warren and Sanders appear to be her candidates of choice after Yang, though if either hopes to earn an official endorsement, they'll likely have to prove themselves just as chuckle-worthy as Yang. A Last Comic Standing-style stand-up competition may be in order. Brendan Morrow

Sen. Bernie Sanders (I-Vt.) is seeing double — his support in New Hampshire, that is.

Between a WBUR poll taken in Dec. 2019 and one taken this month, Sanders nearly doubled his support in the early primary state from 15 percent to 29 percent. And while he was previously behind both former South Bend, Indiana, Mayor Pete Buttigieg and former Vice President Joe Biden, Sanders now has a solid lead over their 17 and 14 percent, respectively.

New Hampshire was also a stronghold in the 2016 campaign for Sanders, where he ended up with 15 delegates to Hillary Clinton's 9. Still, more candidates this time likely will translate into a more split vote.

It's important to note this poll isn't approved by the DNC, so its results don't count toward qualifying for the next Democratic debate. Both Andrew Yang and Rep. Tulsi Gabbard (D-Hawaii) earned five percent in this poll, which would've given them a step toward qualifying.

WBUR and the MassInc Polling group surveyed 426 likely voters via landline and cell phone from Jan. 17–21 with a margin of error of 4.8 percentage points. Kathryn Krawczyk