Technologies

Rare binary star, spotted for the first time, answers a long-standing question

This breakthrough could fill a gap in the stellar evolutionary timeline.

The universe is a star museum. Up close, we have our beloved sun in its middle age. Farther out, we’ll find white dwarfs nearing the end of their days. Peer deeper, and you’ll stumble upon hyper-dense neutron stars on the brink of turning into black holes. Now, for the first time, scientists have uncovered a star exhibit that, for years, has only been a hypothesis.

Technically, the team’s discovery is of a binary star system, or one star orbiting another. In this case, the smaller companion is eating the larger star, and very soon, the sparkly orb being chomped on will become a rare form of white dwarf, or late-stage star, called an extremely low mass, or ELM, white dwarf.

They’ve published a paper explaining their findings in this month’s issue of Monthly Notices of the Royal Astronomical Society.

Though fascinating in itself, the sighting of the deteriorating binary star could also fill an empty slot in a long-standing cosmic puzzle.

«This is exciting; it’s a missing evolutionary link in binary star formation models that we’ve been looking for,» Kareem El-Badry, lead author of the paper and a researcher from the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, said in a statement.

Zooming out from the binary star itself, El-Badry’s discovery fills a gap in our knowledge of how ELM white dwarfs are generated in the first place. We know ELM white dwarfs exist, as scientists have already pinpointed them, but these stellar bodies pose a conundrum.

According to astronomical calculations, experts say, for a star to naturally reach the mass of an ELM white dwarf, it would need to have been born over 13.8 billion years ago. The issue is, the universe itself is only 13.8 billion years old — so that doesn’t really make sense with what we know about the cosmos so far.

Therefore, the only way these stars could possibly be formed within the universe’s timeline is if an external force created them. That force, theorists say, could be the gravitational pull of a companion in a binary star system that’s pulling matter away from the other until the latter object becomes an ELM white dwarf. Seems intuitive, but for a long time, that was just a hypothesis.

Scientists have come upon binary star systems called cataclysmic variables where regular, massive stars are being consumed by a companion star. They’ve even recorded ELM white dwarfs with companions no longer consuming them. It’s easy to extrapolate that an intermediate step would involve an almost-ELM white dwarf with a companion star eating away at it, but no one had seen such a sight.

Thanks to El-Badry’s revelatory documentation, the transitional step appears to be proven at last.

Star hunting

El-Badry used a wide array of star data, several astronomical surveys and his own firsthand observations with the Shane Telescope at the Lick Observatory in California to locate the unique binary star. He’d come up with 50 potential candidates of transitional ELM white dwarfs and ultimately zeroed in on 21 options.

«100 percent of the candidates were these pre-ELMs we’d been looking for,» he explained in the statement. «They were more puffed up and bloated than ELMs. They also were egg-shaped because the gravitational pull of the other star distorts their spherical shape.»

Aptly, he compares the importance of this breakthrough to biological studies of organisms. «You go out into the jungle and find an organism. You describe how big it is, how much it weighs — and then you go on to some other organism,» he said. «You see all these different types of objects and need to piece together how they are all connected.»

Like the ever-advancing tree of life, El-Badry’s new evidence of ELM white dwarfs helps to unveil the entirety of our cosmic star gallery. «We found the evolutionary link between two classes of binary stars — cataclysmic variables and ELM white dwarfs — and we found a decent number of them,» he said.

Next, he hopes to delve into the other 29 pre-ELM white dwarf star candidates to enrich the universe’s star museum even further.

Technologies

Today’s NYT Mini Crossword Answers for Monday, May 19

Here are the answers for The New York Times Mini Crossword for May 19.

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

Today’s NYT Mini Crossword is pretty easy. 5-Across, «one for whom every day is Boxing Day,» stumped me because I really wanted the answer to have something to do with cats. (Spoiler: It did not.) Need some help with today’s Mini Crossword? Read on. And if you could use some hints and guidance for daily solving, check out our Mini Crossword tips.

The Mini Crossword is just one of many games in the Times’ games collection. If you’re looking for today’s Wordle, Connections, Connections: Sports Edition and Strands answers, you can visit CNET’s NYT puzzle hints page.

Read more: Tips and Tricks for Solving The New York Times Mini Crossword

Let’s get at those Mini Crossword clues and answers.

Mini across clues and answers

1A clue: Network satirized on «30 Rock,» for short
Answer: NBC

4A clue: Sport played on horseback
Answer: POLO

5A clue: One for whom every day is Boxing Day?
Answer: MOVED

6A clue: Like correct letters in Wordle
Answer: GREEN

7A clue: Blend together
Answer: MELD

Mini down clues and answers

1D clue: «Invisible Man» or «Little Women»
Answer: NOVEL

2D clue: Run in the wash
Answer: BLEED

3D clue: What bourbon whiskey is primarily made from
Answer: CORN

4D clue: Tiny hole in the skin
Answer: PORE

5D clue: Longtime movie studio acquired by Amazon in 2022
Answer: MGM

How to play more Mini Crosswords

The New York Times Games section offers a large number of online games, but only some of them are free for all to play. You can play the current day’s Mini Crossword for free, but you’ll need a subscription to the Times Games section to play older puzzles from the archives.

Technologies

Today’s NYT Connections: Sports Edition Hints and Answers for May 19, #238

Hints and answers for the NYT Connections: Sports Edition puzzle, No. 238, for May 19.

Looking for the most recent regular 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 and Strands puzzles.

Connections: Sports Edition might be tough today if, like me, you don’t know what «loge» means. Read on for hints and the answers.

Connections: Sports Edition is out of beta now, making its debut on Super Bowl Sunday, Feb. 9. That’s a sign that the game has earned enough loyal players that The Athletic, the subscription-based sports journalism site owned by the Times, will continue to publish it. It doesn’t show up in the NYT Games app but now appears in The Athletic’s own app. Or you can continue to play it free online.

Read more: NYT Connections: Sports Edition Puzzle Comes Out of Beta

Hints for today’s Connections: Sports Edition groups

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

Yellow group hint: Brag.

Green group hint: Where’s my seat?

Blue group hint: City that never sleeps.

Purple group hint: Opposite of go.

Answers for today’s Connections: Sports Edition groups

Yellow group: Boast

Green group: Stadium seating sections

Blue group: New York Knicks

Purple group: ____ stop

Read more: Wordle Cheat Sheet: Here Are the Most Popular Letters Used in English Words

What are today’s Connections: Sports Edition answers?

The yellow words in today’s Connections

The theme is boast. The four answers are crow, gloat, grandstand and showboat.

The green words in today’s Connections

The theme is stadium seating sections. The four answers are bleacher, loge, suites and upper deck.

The blue words in today’s Connections

The theme is New York Knicks. The four answers are Bridges, Hart, McBride and Towns.

The purple words in today’s Connections

The theme is ____ stop. The four answers are back, jump, pit and short.

Technologies

Blade Runner: 18-Rotor «Volocopter» Moving from Concept to Prototype

It may look "nutty" and like a "blender," but the designers say the craft could challenge helicopters

Inventor and physicist Thomas Senkel created an Internet sensation with the October 2011 video of his maiden—and only—test flight of a spidery proof-of-concept 16-rotor helicopter dubbed Multicopter 1. Now the maker of the experimental personal aviation craft, the European start-up e-volo, is back with a revised «volocopter» design that adds two more rotors, a serial hybrid drive and long-term plans for going to 100 percent battery power.

The new design calls for 1.8-meter, 0.5-kilogram carbon-fiber blades, each paired with a motor. They are arrayed around a hub in two concentric circles over a boxy one- or two-person cockpit.

After awarding the volocopter concept a Lindbergh Prize for Innovation in April, Yolanka Wulff, executive director of The Charles A. and Anne Morrow Lindbergh Foundation, admitted the idea of the multi-blade chopper at first seems «nutty.» Looking beyond the novel appearance, however, she says, e-volo’s concept excels in safety, energy efficiency and simplicity, which were the bases of the prize.

All three attributes arrive thanks largely to evolo’s removal of classic helicopter elements. First, the energy-robbing high-mass main rotor, transmission, tail boom and tail rotor are gone. The enormous blades over a normal chopper’s cabin create lift, but their mass creates a high degree of stress and wear on the craft. And the small tail rotor, perched vertically out on a boom behind the cabin, keeps the helicopter’s body from spinning in the opposite direction as the main blades, but it also eats up about 30 percent of a helicopter’s power.

The volocopter’s multiple rotor blades individually would not create the torque that a single large rotor produces, and they offer redundancy for safety. Hypothetically, the volocopter could fly with a few as 12 functioning rotors, as long as those rotors were not all clustered together on one side, says Senkel, the aircraft’s co-inventor and e-volo’s lead construction engineer.

Without the iconic two-prop configuration, the craft would be lighter, making it more fuel efficient and reducing the physical complexity of delivering power to the top and rear blades from a single engine. Nor would the volocopter need an energy-hungry transmission. In fact, «there will be no mechanical connection between the gas engine and the blades,» Senkel says. That means fewer points of energy loss and more redundancy for safety.

E-volo’s design eliminates the dependence on a single source of power to the blades. As a serial-hybrid vehicle, the volocopter would have a gas-fueled engine, in this case an engine capable of generating 50- to 75 kilowatts, typical of ultralight aircraft. Rather than mechanically drive the rotors, the engine would generate power for electric motors as well as charge onboard lithium batteries. Should it fail, the batteries are expected to provide enough backup power so the craft could make a controlled landing.

Whereas helicopters navigate by changing the pitch of the main and tail rotor blades, the volocopter’s maneuverability will depend on changing the speed of individual rotors. Although more complex, it is more precise in principle to control a craft using three to six redundant microcontrollers (in case one or more fails) interpreting instructions from a pilot using a game console–like joystick—instead of rudder pedals, a control stick and a throttle.

Wulff’s first impression about the volocopter’s design is not uncommon. E-volo’s computer-animated promotional videos of a gleaming white, carbon-fiber and fiberglass craft beneath a thatch of blades recall the many-winged would-be flying machines of the late 19th century. This point is not lost on Senkel.

«I understand these skeptical opinions,» he says. «The design concept looks like a blender. But we really are making a safe flying machine.»

That would be progress in itself. Multicopter 1 looked like something from an especially iffy episode of MacGyver, complete with landing gear that involved a silver yoga ball. Senkel rode seated amid all those rotors powered only by lithium batteries. Multicopter 1 generated an average of 20 kilowatts for hovering and was aloft for just a few minutes.

There’s a reason why the experimental craft flew briefly and only once.Senkel describes that first craft as «glued and screwed together.» Seated on the same platform as the spinning blades, he says, «I was aware of the fact that I will be dead, maybe. Besides, we showed that the concept works. What do we win if we fly it twice?» he asks rhetorically.

Other than putting the pilot safely below the blades, the revised volocopter design would operate largely the same as the initial prototype. The design calls for three to six redundant accelerometers and gyroscopes to measure the volocopter’s position and orientation, creating a feedback loop that gives the craft stability and makes it easier to fly, Senkel says.

The volocopter’s revised prototype under construction could debut as soon as next spring. The first production models, available in perhaps three years, are expected to fly for at least an hour at speeds exceeding 100 kilometers per hour and a minimum altitude of about 2,000 meters, still far shy of standard helicopter’s normal operating altitude of about 3,000 meters. «This could change our lives, but I don’t expect anything like that for 10 years,» Senkel adds.

Given that most of the technology needed to build the volocopter is already available, «this idea is fairly easy to realize,» says Carl Kühn, managing director of e-volo partner Smoto GmbH, a company that integrates electric drive systems and related components.

Like Senkel, Kühn has modest short-term expectations despite his repeated emphasis on the standard nature of the technology involved. «I guess that e-volo will have [a prototype] aircraft in three years that can do the job—that it will lift one or two persons from one point to another,» he says.

The biggest immediate limitations appear to be regulatory. For instance, European aviation regulators consider any electrical system greater than 60 volts to be high voltage and regulate such systems more aggressively, Kühn says. As a result, the volocopter will operate below that threshold. The craft will also need to weigh no more than 450 kilograms to remain in the ultralight category, which is likewise subject to fewer government aviation regulations, according to Senkel.

The Lindbergh Foundation’s Wulff says the organization’s judges felt e-volo had «a greater than 50 percent chance of succeeding, or they wouldn’t have given them the innovation award.» Asked if she would line up to fly one someday, she says, «I sure would. It looks very compelling to me.»