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A key to the mystery of fast-evolving genes was found in ‘junk DNA’

A long-standing puzzle in evolution is why new genes — ones that seem to arise out of nowhere — can quickly take over functions essential for an organism’s survival.

A new study in fruit flies may help solve that puzzle. It shows that some new genes quickly become crucial because they regulate a type of DNA called heterochromatin. Once considered “junk DNA,” heterochromatin actually performs many important jobs, including acting like a tightly guarded prison: It locks up “bad actor” genes, preventing them from turning on and doing damage.

Heterochromatin is also one of the fastest-changing bits of DNA in the body, so the genes that regulate it have to adapt quickly just to keep up, evolutionary biologist Harmit Malik at the Fred Hutchinson Cancer Research Center in Seattle and his colleagues report online November 10 in eLife.

“The work is a milestone,” said Manyuan Long, an evolutionary biologist

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SpaceX’s Starship could help clean up space junk in orbit, says CEO

  • SpaceX’s Starship rocket system could help clear out junk that has been left in Earth’s orbit, according to Gwynne Shotwell, the company’s president and CEO. 
  • “It’s not going to be easy, but I do believe Starship offers the possibility of going and doing that,” Shotwell said in an online interview with Time Magazine. 
  • Daniel Oltrogge, director at the Center for Space Standards and Innovation, told Business Insider: “Space debris is increasingly of concern and the collision of two massive space debris objects… pose the greatest environmental risk.”
  • Oltrogge said it’s estimated that there may be around 760,000 objects larger than a centimeter in size in orbit today.
  • Visit Business Insider’s homepage for more stories.

SpaceX’s Starship rocket system could help solve the problem of space junk, according to the company’s president and chief operating officer. 

“There’s rocket bodies littering the space environment, and dead satellites,” said Gwynne Shotwell in an

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2 large pieces of space junk nearly collided in ‘high risk’ situation

Two pieces of space junk, each about the weight of a compact car, had a close encounter on October 15 some 620 miles above Earth. If they had collided—experts put the odds at about 5 or 10 percent before closest approach—the smashup would have created a cloud of debris that would jeopardize other satellites and spacecraft for decades.

The two objects are a defunct Russian navigation satellite launched in 1989 and a spent Chinese rocket part from a 2009 launch. Calculations by LeoLabs, a California-based company that tracks objects in low-Earth orbit, pegged the moment of closest approach at 8:56 p.m. ET on October 15 above the southern Atlantic Ocean, just off the coast of Antarctica. About an hour after the moment of closest approach, LeoLabs confirmed that there was “no indication of collision,” after the two objects passed over the company’s New Zealand tracking station.

The pass was another

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Two Massive Pieces Of Space Junk At ‘Very High Risk’ Of Colliding Thursday Evening

UPDATE: On Wednesday, updated data from LeoLabs predicts the two objects will come within just 12 meters of each other, twice as close as previously estimated.

A defunct Russian satellite and a spent Chinese rocket just floating around high over Earth could smash into each other within a few days, potentially creating a big mess in orbit with potentially dire long-term consequences.

LeoLabs, which tracks space debris, put out the alert on Tuesday warning that the two large hunks of junk will come within 25 meters of each other and have up to a twenty percent chance of colliding Thursday evening.

That’s considered way too close for comfort by space standards. The two objects have a combined mass of 2,800 kilograms and if they were to smash into each other, the “conjunction” could create thousands of new pieces of space

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Pieces of orbiting space junk ‘avoid collision’

Artwork image of space debris
There is growing concern about the potential for more collisions in space (Artwork image)

Two items of space junk expected to pass close to one another have avoided collision, said a company which uses radar to track objects in orbit.

LeoLabs had said a defunct Russian satellite and a discarded Chinese rocket segment were likely to come within 25m of each other.

It said there were no signs of debris over Antarctica on Friday morning.

Other experts thought Kosmos-2004 and the ChangZheng rocket stage would pass with a far greater separation.

With the objects having a combined mass of more than 2.5 tonnes and relative velocity of 14.66km/s (32,800mph), any collision would have been catastrophic and produced a shower of debris.

And given the altitude of almost 1,000km, the resulting fragments would have stayed around for an extremely long time, posing a threat to operational satellites.

LeoLabs, a Silicon Valley

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