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After 20 years in space and 13 years orbiting Saturn, the veteran spacecraft spent its last 90 seconds or so firing its thrusters as hard as it could to keep sending Saturnian secrets back to Earth for as long as possible.

The spacecraft entered Saturn’s atmosphere at about 3:31 a.m. PDT on September 15 and immediately began running through all of its stabilizing procedures to try to keep itself upright. The signal that Cassini had reached its destination arrived at Earth at 4:54 a.m., and cut out about a minute later as the spacecraft lost its battle with Saturn’s atmosphere.
“The signal from the spacecraft is gone, and within the next 45 seconds, so will be the spacecraft,” Cassini project manager Earl Maize announced from the mission control center at NASA’s Jet Propulsion Lab. “I hope you’re all as deeply proud of this amazing accomplishment. Congratulations to you all. This has been an incredible mission, an incredible spacecraft, and you’re all an incredible team. I’m going to call this the end of mission. Project manager, off the net.”

With that, the mission control team erupted in applause, hugs and some tears.
It’s the end of an era. But the spacecraft’s last moments at Saturn will answer questions that couldn’t have been addressed any other way.
Going out in a blaze of glory seems fitting. Since its launch in 1997, the probe traveled a total of 7.9 billion kilometers. It gathered more than 635 gigabytes of science data and took more than 450,000 images. It completed 294 orbits of Saturn, discovered six named moons and made 162 close, deliberate flybys of the ringed planet’s largest and most interesting moons.
The last flyby sealed Cassini’s fate. On September 11, at 12:04 p.m., Cassini passed by Saturn’s largest moon Titan one last time ( SN Online: 9/11/17 ). The moon’s gravity nudged Cassini on an irretrievable trajectory into the giant planet’s atmosphere.
Also blame the moons — particularly lake-dappled Titan and watery Enceladus — for why Cassini went out in such dramatic fashion. The mission team decided to sacrifice the spacecraft when it ran out of fuel, rather than risk a collision with one of those potentially habitable moons and contaminating it with any still-lingering earthly microbes.

“Because of planetary protection and our desire to go back to Enceladus, go back to Titan, go back to the Saturn system, we must protect those bodies for future exploration,” Jim Green, director of NASA’s planetary science division, said at a news conference on September 13.

Even in its months-long death spiral, Cassini collected unprecedented observations. Starting in April, the spacecraft made 22 dives through the unexplored region between Saturn and its rings. Measurements of the gravity and composition in that zone will help solve outstanding mysteries. How long is Saturn’s day? How much material is in the rings? When and how did the rings form?

To answer that last question in particular, “you have to fly between the planet and the rings,” says planetary scientist Matthew Hedman of the University of Idaho in Moscow, who uses Cassini data to study the rings. “That’s risky. We had to wait until the end of the mission to take that risk.”
On September 13 and 14, Cassini took a last look around the Saturn system’s greatest hits, taking a color mosaic image of Saturn and the rings, a movie sequence of Enceladus setting behind Saturn, Titan and tiny moonlets in the rings that pull the icy ring particles around themselves to form features called propellers.

Inside the mission control center on the afternoon of September 14, a hushed operations team waited for Cassini to come online for the last time to start sending the last pictures back (SNOnline: 9/15/17). Then flight engineer Michael Staab at JPL suddenly broke the silence. “Yeah!” he yelled, pumping both arms in the air. Cassini’s last signal had just come in.

“That tells us that the spacecraft is nice and healthy, she’s doing just fine. She’s doing exactly what she’s supposed to do, like she’s done for 13 years,” Staab said. “We’re just gonna track her now, all the way in.”
In the wee hours of September 15, the spacecraft reconfigured itself to shift from a recording device to a transmitting probe. As of that moment, its last and only job was to stream everything it could sense directly back to Earth in real time. Turning so that its ion neutral mass spectrometer was facing directly towards Saturn, Cassini could taste the atmosphere for the first time and investigate a phenomenon called “ring rain,” in which water and ice from the rings splash into the atmosphere. This idea was introduced in the early 1980s, but Cassini has already shown that it’s more complicated than previously thought.

“We’re trying to find out exactly what is coming from the rings and what is due to the atmosphere,” Hunter Waite, Cassini team lead for the mass spectrometer instrument and an atmospheric scientist at the Southwest Research Institute in San Antonio, said at the Sept. 13 news conference. “That final plunge will allow us to do that.”
That plunge happened at about 3:31 a.m., when Cassini entered the atmosphere about 10 degrees north of the equator, falling at around 34 kilometers per second. It took data constantly, directly measuring the temperature, magnetic field, plasma density and composition of the upper layers of Saturn’s atmosphere for the first time ever.
When it hit the atmosphere, Cassini started firing its thrusters to keep its antenna pointed at Earth despite the forces of the atmosphere trying to knock it askew. But about a minute later, the atmosphere won, when Cassini was about 1,400 kilometers above the cloud tops.

What happened next, scientists can only imagine. Models suggest this fiery demise: The spacecraft attempted to stabilize itself, but to no avail. It started to tumble faster and faster. Atmospheric friction broke the spacecraft apart, bit by bit — first its thermal blankets burned off, then aluminum components started to melt. The spacecraft probably fell another 1,000 kilometers as it disintegrated like a meteor, Maize said.

Saturn’s atmosphere crushed and melted the bits and pieces, until they completely dissociated and became part of the very planet the spacecraft had been sent to observe.

When all was said and done, the spacecraft lasted about 30 seconds longer than expected. That may help ensure the team got enough data to figure out Saturn’s rotation period, science team member Michele Dougherty of Imperial College London said at a post-mission news conference September 15. “I’m hoping we can do it, I’m not going to promise. Ask me in three months’ time.”

There are no planned future missions to Saturn, although some Cassini alumni are already working on proposals.
Outer solar system astronomers are now setting their sights on Jupiter and its icy, possibly life-friendly moons. The European Space Agency’s Jupiter Icy Moons Explorer (JUICE) and NASA’s Europa Clipper both hope to launch around 2022. Those missions may pave the way for a lander on Europa (SN Online: 2/18/17), which could directly look for life in that moon’s subsurface seas.

Planetary scientist Kevin Hand at JPL, who is leading the science definition team for the proposed Europa lander, feels a debt to Cassini.

“When you’re at the earliest frontiers of exploration, it’s hard to feel sad,” he said. “The wake we’re experiencing right now for Cassini, it’s not so much an end but the early steps that pave the way for the next stage of exploration.”

Even Maize is more proud than mourning.

“This is exactly the way we always planned it. It’s sad that we’re losing this incredible discovery machine,” he said in the moments leading up to Cassini’s disintegration. “But the real sense here is just, all right, we got it!”

In a big step toward catching up with the rest of the world, the United States cleared the way for using mosquitoes as a commercial pest control for the first time.

The U.S. Environmental Protection Agency has approved using a strain of male Asian tiger mosquitoes (Aedes albopictus) as a biopesticide in the District of Columbia and 20 states, including California and New York. Kentucky-based MosquitoMate was granted the right to sell these mosquitoes, called ZAP Males, for the next five years, the agency announced November 7.
These male mosquitoes are not genetically modified. Instead they carry a strain of Wolbachia bacteria that turns them into saboteur dads. When they mate with wild females not carrying the strain, the offspring will die and the population should dwindle. Males don’t bite, so releasing them should not add extra vexation.

Releases of Wolbachia-bearing mosquitoes for pest control already go on in other countries, such as Brazil, although with a different bacterial strain and a different strategy.

This same company has also been testing the effectiveness of a different mosquito species, Aedes aegypti, also carrying bad-dad Wolbachia, near Key West, Fla. (These mosquitoes are not commercially available.) The tests “ended a bit early due to [Hurricane] Irma,” says Stephen Dobson of MosquitoMate, “but we think that we have some good data despite this complication.”

The WBO welterweight belt will be on the line when Terence Crawford and Shawn Porter meet in Las Vegas on Saturday night.

Crawford, widely considered one of the best fighters in the world regardless of weight class, enters the bout with a perfect 37-0 record. He has successfully defended the WBO title four times since taking it from Jeff Horn back in 2018.
Porter holds a record of 31-3-1, but his three losses have come against strong opponents in Kell Brook, Keith Thurman and Errol Spence Jr. He represents the toughest test of Crawford's career.

"Hands down, I feel like this is a fight where I can make a huge statement in the welterweight division," Crawford said (via Boxing Scene). "Because everything I’ve done, the question is always, 'Well, what about welterweight?' Welterweight this, or welterweight that. This is one of the top welterweights that I am facing.
"This is my time to show the world who Terence Crawford really is in the welterweight division."

Here's everything you need to know about watching the Crawford vs. Porter fight.

A big win over the Denver Nuggets was soured for the Dallas Mavericks in the final minute when Luka Doncic appeared to suffer an ankle injury.

After the game against Denver, Doncic is averaging 24.9 points, 8.3 rebounds and 7.9 assists on the season.

What's next for Doncic? Here's everything we know about his injury and the latest news on when he may return to the court.
What is Luka Doncic's injury?
The injury was sustained as the Mavericks superstar attempted to block an Austin Rivers layup. Rivers' body appeared to roll over the ankle of Doncic in the aftermath of the play.
The win improved Dallas to 9-4 on the season, good for third in the Western Conference.

Doncic was his usual dominant self in the win, finishing with 23 points, eight rebounds, 11 assists, two steals and a block across 37 minutes of play.

How long will Luka Doncic be out?
Doncic was unavailable for media postgame as he was undergoing treatment, with head coach Jason Kidd unable to give an immediate update.

“Luka walked off on his own power,” Kidd said.

“I think he got his lower left leg rolled up on, so we’ll see how he feels.”

The following day, The Athletic's Shams Charania reported that tests on Doncic's left ankle and knee "showed no damage." ESPN's Tim MacMahon added that his injury is believed to be "not too serious" and that he'll likely miss some time but hopefully not an extended stretch.

Doncic sat out the Mavs' loss to the Phoenix Suns on Nov. 17 and is doubtful for the team's rematch on Nov. 19.

Mavericks upcoming schedule 2021-22
Date Opponent Time (ET)
Fri, Nov. 19 at Phoenix 10:00 PM
Sun, Nov. 21 at LA Clippers 3:30 PM
Tue, Nov. 23 at LA Clippers 10:30 PM
Sat, Nov. 27 vs. Washington 8:30 PM
Mon, Nov. 29 vs. Cleveland 8:30 PM
Wed, Dec. 1 at New Orleans 8:00 PM
Doncic has been a durable player throughout the early portion of his career, playing all 13 games this season so far, after missing just six across the 72-game regular season in 2020-21.

Stay tuned for further updates from the team on the status of Doncic and his ankle.

There was a moment in the first half, not even 20 minutes into the United States’ World Cup qualifier at Jamaica, that American midfielder Yunus Musah gathered the ball in the center of the field at Independence Park and contemplated one of his favored rampages toward the opposing goal. He had demolished Mexico with his physical strength and dribbling skill, and it was time to do the same to the Reggae Boyz.

As Musah advanced, though, the ball did not. The field — yes, the field — had other ideas.
It’s not always the opposing fans or the refs or the pressure of the circumstance. Sometimes, it’s as simple as lacking the comforts of home. For a squad that included three teenagers and was the second-youngest the USMNT ever deployed for a qualifier, being unable to count on the ball rolling evenly was among the many reasons it left Jamaica with a 1-1 draw and a single point to add toward its total.

“We’re not looking at it as a disappointing result. We’re looking at it as a good result,” U.S. coach Gregg Berhalter told reporters. “Any time you can get a point away from home is a good thing in CONCACAF qualifying. I want to be very clear by saying that.

“I think for the guys to have their heads down because we wanted more is completely natural, but this is a point that we’ll absolutely take on the road.”

It’s a point more precious than American fans are likely to appreciate. The U.S. easily could have lost, given one blown opportunity at a wide-open tap-in for Jamaica’s Bobby Reid and a disallowed goal from his teammate, Damian Lowe, on an 84th-minute set piece.

The U.S. took a 1-0 lead on forward Timothy Weah’s inventive 11th-minute goal, which required a sweet feed from striker Ricardo Pepi, two nifty moves from Weah and a left-footed finish past ace goalkeeper Andre Blake. That was answered 11 minutes later, though, when Jamaica’s Michail Antonio — currently third in the Premier League in goals for West Ham United — drove to the left against U.S. midfielder Tyler Adams, stopped and cut back to his right foot and left Adams behind. He blasted a searing shot from 34 yards that found the top right corner, beyond the reach of goalkeeper Zack Steffen.

“Obviously, it was a rough game. Not the result that we wanted,” Weah said. “We knew it was going to be difficult.

“Conditions were rough, but that’s no excuse. We wanted to execute, but it wasn’t there today.”

It’s difficult to reconcile this torpid performance against the brilliance of Friday night’s victory over Mexico. But combining the two gives the USMNT four points from the two-game window in CONCACAF qualifying, and still leaves it in position to earn an automatic position in the 2022 World Cup field.

The Americans now have five points from four road games, slightly ahead of the “win your home games, draw on the road” standard that tends to assure qualification in this format. However, they’re also a couple points behind at home because of a 1-1 September draw against Canada. Their 15 points through eight games is three more than they earned in the entire 10-game qualifying round when failing to qualify for Russia 2018.

Qualifying will not be easy. Not that it ever has been.

“It was difficult conditions, it really was,” Berhalter said. “Controlling the ball, playing the ball was challenging. You can chalk it up to simply that. It was challenging field conditions, and the movements weren’t always clean. That’s something you can’t control.”

This is not something Musah would have encountered often while growing up in Italy or later England, where he trained in the Arsenal youth program. Pristine pitches predominated once he moved to Spain to join Valencia in 2019, and that’s what was in place in Cincinnati — even though it rained — when the USMNT dominated rival Mexico to earn a 2-0 victory and take over first place in the final round of World Cup qualifying.

After that moment in the 18th minute, though, Musah seemed to abandon the skill that had made him such a force against Mexico. With midfielder Weston McKennie out because of a yellow-card suspension — and with Musah muted and fellow teen Gianluca Busio just a shade hesitant in his first qualifying start — the Americans lacked the engine that had driven them four days earlier.

Berhalter allowed that he thought Musah was bothered by the conditions, then told Sporting News he also was bothered by a case of strep throat.

“We could tell that was taking a toll on him,” Berhalter told SN. “I don’t want this to be about the field, I really don’t. It was the same for both teams. We had enough time to be moving the ball. It was difficult, but we had enough time. And it’s just something you have to deal with. And we’re used to dealing with that.”

Are they, though? Most of the USMNT still has played in just a few CONCACAF road qualifiers. Hesitation was horrifically huge for many of those who played Tuesday. So many circumstances that could have been devastating developed because players expected balls to roll into their feet, only to see them die and be beaten to the play by the opposition. There were passes fed in the direction of teammates that lacked the necessary pace, including one to Steffen that traveled so slowly it nearly allowed Jamaica another simple scoring chance.

That’s what happened on the play that set Reid up, with U.S. right back DeAndre Yedlin waiting too long to pursue what should have been a simple clearance. Instead, Jamaica was able to feed a cross to the far post, where left back Antonee Robinson tried to clear it for the Americans. Instead, he knocked it directly across the goal to Reid. What should have been a simple tap-in was blasted over the crossbar because Reid panicked.

In the 84th minute, Jamaica’s corner kick was pursued by Lowe directly in front of the goal, but he was called for climbing over defender Walker Zimmerman’s back to head the ball past. Berhalter said he heard the whistle quickly, so he believed referee Juan Gabriel Calderon of Costa Rica was convinced of his call.

“When you think about the youth of this group, the inexperience of this group in CONCACAF qualifying, we’re on the right track,” Berhalter said. “Just thinking about it, you don’t often get where you’re in a qualifying competition, one venue is freezing cold, and the next venue is this tropical climate.

“Most continents, when they have qualifying, the weather’s consistent. So we’re going through a lot here, man. We’re learning on the fly. The guys have done a good job with that. We’ll take our position now and focus on 2022.”

To be clear, he meant the six games remaining in qualifying that will be played in the new year — not “Qatar 2022.”

The Americans are not there yet. And the road to get there will remain bumpy.