On the eve of Lt. Col. Alexander Vindman's public testimony before House impeachment investigators, Sen. Ron Johnson (R-Wis.) sent a letter to House Republicans, questioning Vindman's credibility.

Vindman, the National Security Council's top Ukraine expert and a Purple Heart recipient, is set to testify on Tuesday. He listened to President Trump's July 25 phone call with Ukrainian President Volodymyr Zelensky, and immediately shared his concerns over Trump's request that Zelensky launch an investigation into a political rival, former Vice President Joe Biden, and his son, Hunter.

In his letter, Johnson opines that there are "bureaucrats and staff members within the executive branch" who have "never accepted President Trump as legitimate and resent his unorthodox style and his intrusion onto their 'turf.' They react by leaking to the press and participating in the ongoing effort to sabotage his policies and, if possible, remove him from office. It is entirely possible that Vindman fits this profile."

Johnson tried to defend Trump throughout the letter, saying he could not recall Trump ever talking to him about the Bidens, while also attacking the whistleblower whose complaint about Trump's call launched the House impeachment inquiry. "If the whistleblower's intention was to improve and solidify the relationship between the U.S. and Ukraine, he or she failed miserably." Catherine Garcia

A research team made a worrisome discovery off the Siberian coast, The Guardian reports. The scientists say they believe they are first to uncover observational evidence that frozen methane deposits in the Arctic Ocean have started to be released after determining that methane levels at the ocean's surface were four to eight times higher than expected.

The deposits are considered "sleeping giants of the carbon cycle" and could theoretically expedite climate change, given that methane has a warming effect 80 times stronger than carbon dioxide over a 20 year period, The Guardian notes. But while the discovery sounds alarming, it's also been met with skepticism from some climate scientists.

Gavin Schmidt, a climatologist and director of the NASA Goddard Institute for Space Studies, argued there is no evidence Arctic methane had a "big effect" even in earlier periods when the region was warmer than it is now.

The scientists who made the discovery, meanwhile, have acknowledged their work is preliminary, and said the scale of methane releases will not be confirmed until they return and analyze the data. Either way, "there is unlikely to be any major" climate effect "at this moment," Swedish scientist Örjan Gustafsson, told The Guardian from the research vessel. But he did maintain his stance that "the process has now been triggered." Read more at The Guardian. Tim O'Donnell

Keith Raniere was sentenced Tuesday to 120 years in prison after being convicted of running a sex trafficking cult called NXIVM.

Raniere founded and ran NXIVM, which he branded as a self-improvement business. But prosecutors say it was a front for Raniere to traffic women and girls and mentally, physically, and sexually abuse them. Raniere's victims gave harrowing victim statements during his trial, detailing how they were blackmailed and otherwise prevented from leaving the cult, some for more than a decade.

Raniere was convicted a year ago on charges of federal sex trafficking and child pornography. He acknowledged wrongdoing within NXIVM, but maintained his innocence even in recent interviews ahead of his sentencing. Other NXIVM members have pleaded guilty to charges related to the cult. NXIVM gained notoriety as the subject of the HBO docuseries The Vow. Kathryn Krawczyk

Guess who's back?

Apple TV+ on Tuesday announced it has signed a deal with comedian Jon Stewart for multiple seasons of a new current affairs show. This will be Stewart's return to television over five years after his departure from The Daily Show, the streamer noted in a statement. Apple TV+ also said Stewart has signed a first-look deal with the company for "projects to be produced and developed for the service."

Stewart's new show was described as a "one-hour, single-issue series" that will "explore topics that are currently part of the national conversation and his advocacy work," and each season will be accompanied by a companion podcast. Since he left The Daily Show, Stewart has been particularly vocal in advocating for 9/11 first responders. Trevor Noah took over as host of The Daily Show in 2015.

Though this new show will mark Stewart's television return, the comedian earlier this year directed the political comedy Irresistible starring Steve Carell. Speaking in an interview with The New York Times in June about whether he wishes he still had his own show, Stewart said, "Sometimes I do. But not the one that I had. The one that I had is in wonderful hands and continues to elevate in a way that I couldn't have. My efficacy for that kind of conversation has passed." Brendan Morrow

President Trump's obsession with 60 Minutes has lasted far longer.

Last week, Trump, Vice President Mike Pence, Democratic presidential nominee Joe Biden, and Sen. Kamala Harris (D-Calif.) all sat with 60 Minutes correspondent Lesley Stahl for interviews ahead of the upcoming election. But Trump didn't exactly stay for long, walking off in the middle of the interview and then complaining about it for days on end.

Trump has since repeatedly attacked Stahl, including at his Tuesday rally in Michigan. Echoing his offensive remark to Megyn Kelly five years ago, Trump declared Stahl had "fire coming out of her eyes" when she asked Trump if he was "ready for some tough questions."

Trump's comments came after TMZ reported CBS had hired a security detail for Stahl after she received a death threat. Someone reportedly called one of Stahl's family members and threatened Stahl and her family shortly before Trump shared the 60 Minutes interview. Kathryn Krawczyk

One week out from Election Day, President Trump's campaign is reportedly pulling advertising out of Florida.

The president's re-election campaign has "all but pulled its advertising" out of the crucial state that he carried in 2016, Bloomberg reported on Tuesday. The campaign reportedly canceled $5.5 million in ad spending in Florida during the final two weeks of the 2020 campaign and is now focusing on four states: Michigan, Minnesota, Ohio, and Pennsylvania.

Trump communications director Tim Murtaugh in a call with reporters on Tuesday predicted that Florida, where Trump and Democratic presidential nominee Joe Biden have been roughly tied in polls, is "going to go the president's way," citing his "ground game" in the state.

Trump's campaign reportedly does still have about $350,000 in advertising spending budgeted for Florida through Election Day, but Bloomberg notes that the president "has cut $24 million from his national ad budget" since Labor Day, whereas Biden "has added $197 million." Read more at Bloomberg.

Update: The Trump campaign in a new statement is disputing Bloomberg's reporting as "horribly wrong," saying that "our ad buying week by week in the state has been consistent, and the reporting on this issue demonstrates a clear misunderstanding of how ad buying works." Brendan Morrow

President Trump's receipts from his own properties keep piling up — but he's not the one paying the bill.

The U.S. government and Trump's supporters have paid at least a combined $8.1 million to Trump's properties throughout his presidency, documents and public records obtained by The Washington Post have so far revealed. Those payments covered everything from rooms for Secret Service agents, to a variety of candles, to even the $3 water Trump and Japan's former prime minister Shinzo Abe sipped at a summit in 2018.

Trump has visited his properties around the world more than 280 times since his inauguration, bringing Secret Service protection and often his family and foreign leaders along with him. During the summit with Abe at Mar-a-Lago, Trump's aides stayed in a $2,600-night house owned by the Trump Organization, records show. When Trump met with Xi Jinping of China, the club charged the government $7,700 for Trump and Xi's dinner. And when Abe returned a year later, taxpayers covered $6,000 worth of floral arrangements for the occasion. Trump's Christmas visit to the club — no foreign visits included — resulted in a $32,400 charge for the Secret Service's guest rooms, the Post reports.

And by holding government-funded events at his properties, Trump has turned them into "magnets for GOP events, including glitzy fundraisers for his own reelection campaign," the Post writes. Trump's campaign and fundraising committee have so far spent $5.6 million at Trump properties, "turning campaign donations into private revenue" even as his campaign war chest ran dry, the Post continues. It all flies in the face of Trump's insistence that he's losing money by serving as president.

"Any suggestion that the president has used his own official travel or the federal government as a way to profit off of taxpayers is an absolute disgrace and lie," White House spokesperson Judd Deere said. Read more at The Washington Post. Kathryn Krawczyk