Technologies

Jupiter’s Moon Callisto Has a Whole Lot of Oxygen Scientists Struggle to Explain

A recent analysis finds up to 1,000 times more molecular oxygen than can be explained by prevailing theories about where it comes from.

Jupiter’s four largest moons are some of the solar system’s most compelling worlds. Io is dotted with active volcanoes, and Europa hides a subsurface ocean many want to check for alien life. Ganymede is the largest moon in the solar system, and Callisto is the system’s most heavily cratered object. Callisto is also home to an emerging mystery: The moon’s thick atmosphere holds a surprising amount of oxygen, and scientists aren’t sure why.

Observers have known about the presence of abundant molecular oxygen at Callisto for a while, with the working assumption being that the influence of Jupiter’s powerful magnetosphere could be knocking molecules of water, hydrogen and oxygen out from Callisto’s icy surface and into the atmosphere.

But when a team of researchers ran the numbers, they found that Jupiter’s magnetism can’t fully explain the amount of molecular oxygen around Callisto.

«There’s a huge discrepancy,» said Shane Carberry Mogan, lead author on a paper about the findings published late last month in the journal JGR Planets. «We were off by something like two orders of magnitude to even three orders of magnitude.»

For the layperson, that means there is 100 to 1,000 times as much molecular oxygen present in Callisto’s atmosphere as the scientists would expect to find if Jupiter’s magnetosphere stripping it out of the icy surface were the sole source.

The discovery of so much oxygen on an alien world may sound like a boon for the possibility that Callisto may support life, but the frozen world is probably far too cold for life as we know it. That said, plentiful oxygen could be useful in generations to cometo explorers who may be able to use it for fuel and life support while traveling around deep space.

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It isn’t clear what’s happening at Callisto to produce so much oxygen, but Carberry Mogan hopes to get a better understanding of processes active in the moon’s surface that may yield an explanation or clues.

«That’s probably Callisto’s most enigmatic feature is its surface,» said Carberry Mogan, who’s a postdoctoral researcher in planetary science at the University of California at Berkeley. «It’s supposed to be an icy body, but when you look at it, it’s mostly this dark surface, anywhere from millimeters to kilometers deep.»

It’s still up for debate whether Callisto’s surface is more rock or ice. The dark material on its surface could also be ice-rich, providing a plentiful source for the mysterious amount of oxygen in the atmosphere.

For help with the mystery, Carberry Mogan is looking to upcoming robotic missions like ESA’s Juice and NASA’s Europa Clipper, which may swing close enough to Callisto to gather new data that could shed light on the puzzle.

«It’s really perplexing,» he said. «The next step is to figure out why there’s this gap between the source [of oxygen] and the observation.»

Technologies

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Technologies

Today’s NYT Strands Hints, Answers and Help for May 20, #443

Here are hints and answers for the NYT Strands puzzle No. 443 for May 20.

Looking for the most recent Strands answer? Click here for our daily Strands hints, as well as our daily answers and hints for The New York Times Mini Crossword, Wordle, Connections and Connections: Sports Edition puzzles.

Today’s NYT Strands puzzle reminds me that I haven’t had a meal in a fancy restaurant in some time. Maybe it’s time to make a reservation. If you need hints and answers, read on.

I go into depth about the rules for Strands in this story.

If you’re looking for today’s Wordle, Connections and Mini Crossword answers, you can visit CNET’s NYT puzzle hints page.

Read more: NYT Connections Turns 1: These Are the 5 Toughest Puzzles So Far

Hint for today’s Strands puzzle

Today’s Strands theme is: Oh, of course!

If that doesn’t help you, here’s a clue: Elegant eats.

Clue words to unlock in-game hints

Your goal is to find hidden words that fit the puzzle’s theme. If you’re stuck, find any words you can. Every time you find three words of four letters or more, Strands will reveal one of the theme words. These are the words I used to get those hints but any words of four or more letters that you find will work:

SITE, FINE, SINE, DINE, PEAS, TEEN, PEER, STEEP, DEER, SEED, SEEN, POET, TREE, NOPE, SEES.

Answers for today’s Strands puzzle

These are the answers that tie into the theme. The goal of the puzzle is to find them all, including the spangram, a theme word that reaches from one side of the puzzle to the other. When you have all of them (I originally thought there were always eight but learned that the number can vary), every letter on the board will be used. Here are the nonspangram answers:

SOUP, SALAD, CHEESE, ENTREE, DESSERT, APPETIZERS

Today’s Strands spangram

Today’s Strands spangram is FINEDINING. To find it, start with the F that’s three letters down on the farthest row to the left, and wind across.

Toughest Strands puzzles

Here are some of the Strands topics I’ve found to be the toughest in recent weeks.

#1: Dated slang, Jan. 21. Maybe you didn’t even use this lingo when it was cool. Toughest word: PHAT.

#2: Thar she blows! Jan.15. I guess marine biologists might ace this one. Toughest word: BALEEN or RIGHT.

#3: Off the hook, Jan. 9. Similar to the Jan. 15 puzzle in that it helps to know a lot about sea creatures. Sorry, Charlie. Toughest word: BIGEYE or SKIPJACK

Technologies

Today’s NYT Connections Hints, Answers and Help for May 24, #713

Hints and answers for Connections for May 24, #713.

Looking for the most recent Connections answers? Click here for today’s Connections hints, as well as our daily answers and hints for The New York Times Mini Crossword, Wordle, Connections: Sports Edition and Strands puzzles.

Today’s Connections puzzle has a fun variety of categories. The purple one appeals to my English major heart. Read on for clues and today’s Connections answers.

The Times now has a Connections Bot, like the one for Wordle. Go there after you play to receive a numeric score and to have the program analyze your answers. Players who are registered with the Times Games section can now nerd out by following their progress, including number of puzzles completed, win rate, number of times they nabbed a perfect score and their win streak.

Read more: Hints, Tips and Strategies to Help You Win at NYT Connections Every Time

Hints for today’s Connections groups

Here are four hints for the groupings in today’s Connections puzzle, ranked from the easiest yellow group, to the tough (and sometimes bizarre) purple group.

Yellow group hint: Goo-goo.

Green group hint: Not shirts.

Blue group hint: City that never sleeps.

Purple group hint: Acclaimed writers.