NASA successfully flew its four-pound helicopter from the surface of Mars early Monday in the first powered flight of an aircraft on another planet, a feat that NASA officials compared to the Wright brothers’ first flight in 1903.

The change is part of an ongoing effort to reverse former president Donald Trump’s hard-line policies and advance President Biden’s efforts to build a more “humane” immigration system.

The Biden administration is privately weighing how to handle the upcoming verdict in the trial of former Minneapolis police officer Derek Chauvin.

Prosecutors never sought to invoke a “red flag” law that would have kept Brandon Hole, who shot and killed eight people before killing himself at an Indianapolis FedEx facility last week, from obtaining guns, even after he had been deemed too dangerous to possess a shotgun, a top law enforcement official said Monday.

Top liberal lawmakers unveiled legislation Monday that would pour more than $100 billion over a decade into modernizing the public housing system and starting a transition to renewable energy, as progressives seek to prod President Biden to expand his far-reaching infrastructure plan.

Capitol Police Officer Brian D. Sicknick suffered two strokes and died of natural causes a day after he confronted rioters at the Jan. 6 insurrection, the District’s chief medical examiner has ruled.

The US government-led missions effort to return hundreds of Americans to the United States in the earliest days of the coronavirus outbreak were plagued by “serious fundamental coordination challenges,” the Government Accountability Office concluded in a report released Monday.

As anti-police violence protests roil a suburb and jurors deliberate in the trial of former Minneapolis officer Derek Chauvin, Minneapolis police on Monday sought to show solidarity with community activists and emphasize that they intend to prioritize de-escalation in the coming days.

Former President Jimmy Carter credited Walter F. Mondale, his onetime vice president who died Monday at 93, with transforming the office from a secondary role to a governing partner with his political skill and personal integrity.

A federal judge on Monday jailed two Proud Boys leaders pending trial in the Jan. 6 Capitol insurrection, handing a victory to US prosecutors in a closely watched conspiracy case accusing the two of planning to disrupt Congress and leading as many as 60 others to impede police that day.

The judge in the trial of former Minneapolis police officer Derek Chauvin on Monday admonished politicians for making what he called irresponsible and disrespectful comments about the case as jurors were sent to deliberate on a case that has already rattled the country.

The French government bears “significant” responsibility for “enabling a foreseeable genocide,” a report commissioned by the Rwandan government concludes about France’s role before and during the horror in which an estimated 800,000 people were slaughtered in 1994.

The Russian penitentiary system released a statement saying that a commission of government doctors had decided on the move for Alexei Navalny, who is now nearly three weeks into a hunger strike. Navalny’s personal doctors have reported that he is suffering from a range of severe symptoms that they call life threatening.

Israel’s prime minister, Benjamin Netanyahu, is pushing for a new law to allow the direct election of the nation’s leader as a way to break the country’s two-year political deadlock.

Since 1959, when Raúl and his older brother, Fidel, led an insurgency against a US-backed dictator to victory, Cuba has been led by a Castro. Now, as Raúl — who is 89 and succeeded his older brother — steps down from the helm of the Communist Party, he leaves a country that is torn by the most brutal economic crisis in decades.

Watching that video is a gut punch, one that should lead a reasonable person to conclude that the force Chauvin used was unreasonable, excessive, and disproportionate to the situation.

Many of the documents that are readily accessible to the public in other states are off-limits here.

Four weeks after Maria’s daughter first disappeared into the bowels of the US immigration system, the two were finally reunited.

The field of education should seize on the sense of urgency that we need to do more and better for our students in this moment of crisis.

All police agencies across our nation need to be seriously overhauled and all training methods and protocols examined and altered radically.

As the coronavirus vaccination drive enters its fifth — and most pivotal — month, appointments opened to all Massachusetts residents age 16 and older on Monday.

If elected, Alex Gray would presumably become the first blind member of the Boston City Council.

Today is Tuesday, April 20, the 110th day of 2021. There are 255 days left in the year.

Acting Mayor Kim Janey has appointed a chief of environment, energy, and open space for the city, the latest Cabinet-level shake-up in the transition from Martin J. Walsh’s administration.

The battle reenactment on the Lexington Green was canceled for a second straight year, a disappointment to community members and history buffs who turn out to see the annual commemoration of the battle between the Minutemen and British soldiers on April 19, 1775.

A brick wall partially collapsed Monday at a home in Boston’s North End, displacing four adults, according to the Fire Department.

A group of activists and lawmakers is challenging the construction of a women’s prison in Norfolk, saying the move would have detrimental effects on the women and their families, and that the money could be better spent elsewhere.

The ocean is a massive ecosystem, so why shouldn’t it have a startup ecosystem all its own? That’s the thinking behind the new BlueSwell Incubator Program hosted by the New England Aquarium and SeaAhead, a local “bluetech” business group that works with maritime-focused startups.

GreenLight, a nonprofit, acts a bit like a venture capital firm by backing social entrepreneurs and helping them replicate and expand their community-focused organizations across the country.

Workers in Bessemer, Ala., voted against forming a union, 1,798 to 738, with about 53 percent of the nearly 6,000 workers at the warehouse casting a vote.

Funding for women-focused digital-health startups rose 105 percent last year to $418 million and was spread across 22 companies, nearly twice the number from a year earlier, according to Rock Health, a San Francisco-based seed and early-stage venture fund.

The two winners each made concrete that trapped carbon dioxide, keeping it out of the atmosphere, where it can contribute to climate change.

Investigators are still trying to determine whether the electric car was operating on Tesla’s Autopilot driver-assist system, or if the company’s “Full Self-Driving Capability” system was in use.

Stories you may have missed from the world of business.

While raising five children, Dr. Rockett helped pioneer the work-life balance for women in the medical field.

Helen McCrory was one of Britain’s most respected actors, making her mark by playing a succession of formidable and sometimes fearsome women, including the matriarch of a crime family on “Peaky Blinders” and the scheming Voldemort ally Narcissa Malfoy in the “Harry Potter” movies.

The first six batters of the game for the Red Sox hit safely, and they were off to the races, giving Nate Eovaldi plenty of support.

Parker was active for Saturday’s game against the Warriors and even played a substantial role in the win.

Some players received vaccinations — with more scheduled for Wednesday — after an enjoyable victory at Fenway Park.

It has been a month of sunny days for the three teams, leaving us very little to complain about.

The Celtics had a six-game winning streak snapped in a 102-96 loss to the Bulls on Monday night.

The lesson learned Monday should be valuable because Chicago coach Billy Donovan played Tatum and Brown like playoff teams will.

The former No. 2 overall pick is looking to re-establish himself as a steady NBA scorer.

Dave Powell, Liverpool Echo, business of football reporter: “I think this is probably a decision which will be irreversible for Fenway Sports Group in terms of their relationship with Liverpool fans.”

Eovaldi touched 100 mph on Monday, but also got swings and misses from Chicago hitters on his cutter, his slider, and his increasingly dominating curveball.

"I've got a lot of trust in the people we have," GM Brian Cashman said Monday, New York sitting at 5-10. "I don't see us reacting to not believing in the staff we have, and the players we have, either."

Patriots players had issued a statement through the NFL Players Association last week saying that "many" would not show up.

Smith, 36, won AP Comeback Player of the Year honors for getting back on the field with Washington last season.

Cassidy had no problem with Tom Wilson's hit on Sean Kuraly, but Garnet Hathaway's boarding of Jarred Tinordi was a different matter.

While the U.S. Opens will not be the first majors to allow fans, they will be the first to hold spectators to a standard of health through the COVID-19 vaccine or testing.

Berklee grad Safiya Leslie — a singer/songwriter and entrepreneur — is giving world music fans a chance to explore the sounds of a different country each month through her Safiya’s World Music Tour Playlist subscription boxes.

You aren’t encouraged to watch and then think about what you saw; you are meant to press the “Skip Intro” button and keep on moving.

Why is the letter writer still thinking about a co-worker? Help.