A second space rock hit Earth after the one that doomed the dinosaurs – a nail in the coffin of the mass extinction

dinosaur asteroid meteor
An artist’s depiction of the moment the Chicxulub asteroid struck in present-day Mexico 66 million years ago.

About 66 million years ago, Earth took a one-two punch, according to a new study.

First came a space rock 6-miles-wide that struck present-day Mexico. The impactor, named Chicxulub, contributed to the demise of the dinosaurs, along with 50% to 75% of life on Earth.

Then, 650,000 years later, a mile-sized asteroid known as Boltysh struck. The rock carved out a 15-mile-wide crater into what is now central Ukraine.

Scientists once thought both Boltysh and Chicxulub contributed to the mass extinction that doomed the dinosaurs. But according to the study published Friday in the journal Science Advances, Boltysh likely impacted Earth long after the last victims of the extinction died out.

“I believe the extinction was essentially done and dusted” by the time Boltysh hit, Annemarie Pickersgill, a researcher at the University of Glasgow who specializes in meteorite impacts and co-author of the new study, told Insider.

While it’s unlikely Boltysh exacerbated the die-off, Pickersgill said the second impact may have delayed Earth’s recovery from the catastrophic extinction.

Analyzing rocks that melted during the Boltysh impact

melt rock from boltysh impact site ukraine
A piece of shocked quartz from the Boltysh impact crater in the Ukraine.

Scientists discovered the Boltysh impact in 2002, and an initial study suggested the asteroid had hit 2,000 to 5,000 years before Chicxulub did.

Pickersgill said that her team had intended to date the Boltysh crater with more precision, but she didn’t expect their findings to upend previous research.

“I was surprised to find that the age for Boltysh was after​ Chicxulub,” she said.

The researchers first analyzed two samples from deep within the crater, more than one-third of a mile underground. The heat from the asteroid impact had melted the rocks, so dating them allowed Pickersgill to piece together when Boltysh hit.

Then, the team looked at samples from a layer of sediment in Montana that coincided with the Chicxulub impact. Using radiometric dating – a technique that determines how long it takes for radioactive material in the rocks to decay – the team determined the Boltysh rocks melted about 650,000 years after Chicxulub struck.

Boltysh may have contributed to a burst of global warming

Chicxulub_impact asteroid
This painting depicts an asteroid slamming into tropical, shallow seas of the sulfur-rich Yucatan Peninsula in what is today southeast Mexico. The aftermath of this immense asteroid collision, which occurred approximately 65 million years ago, is believed to have caused the extinction of the dinosaurs and many other species on Earth.

The updated age for the Boltysh crater coincides with a period of intense global warming known as the lower C29 hyperthermal, the study authors said.

During a hyperthermal event, which can last up to 40,000 years, average global temperatures can increase by 5.4 degrees Fahrenheit (3 degrees Celsius).

Pickersgill’s team hasn’t determined yet whether the asteroid caused the hyperthermal.

But she said there is evidence that suggests Chicxulub first cooled the Earth’s climate, then warmed it.

When the dino-killing rock hit, it kicked up a cloud of dust, sulfur, and carbon dioxide into the atmosphere. That gaseous haze blocked the sun for a couple of decades, one study suggests, cooling the Earth.

During those few decades, most of Earth’s land and marine species went extinct.

Eventually, the Chicxulub cloud dissipated and the remaining sulfur and carbon in the atmosphere – which trap heat on Earth’s surface – started warming the planet.

But once Boltysh hit, that impact may have released additional gases into the air and exacerbated that warming. This could’ve made it more difficult for Earth’s species to recover following the mass extinction.

Research suggests it took 9 million years for the number of different species in North America to return to pre-Chicxulub levels.

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NASA is finally advancing a space telescope that could track down dangerous asteroids before they strike Earth

neocam asteroid hunter spacecraft discovery nasa jpl caltech
An artist’s concept of the NEOCam asteroid-hunting mission.

NASA is finally moving forward with a space telescope that could spot asteroids heading dangerously close to Earth.

The Near-Earth Object Surveyor Mission – NEO Surveyor, for short – has passed a key review, and NASA announced Friday that it’s moving it to the next stage of development. Now engineers can start building new parts for the telescope, thereby keeping the mission on track for a 2026 launch.

“I’m over the moon,” Amy Mainzer, who leads the project, told Insider. “We are excited to do our part to help cross the asteroid-impact issue off the world’s list of worries.”

To protect the planet from an incoming asteroid, experts estimate they’d need five to 10 years’ warning that a space rock was headed our way. Right now, an asteroid could easily approach Earth without anyone seeing it, since telescopes on the ground can only do limited surveillance.

“What you want to do is find them early, find them as early as possible – as in years, or even decades, before they pose a threat,” Paul Chodas, the manager of NASA’s Center for Near-Earth Object Studies, previously told Insider. “The dinosaurs didn’t have a space program, and look what happened to them. We have a space program. And given enough time, we can do something about this threat.”

NEO Surveyor would help NASA catalogue nearby asteroids and chart their paths through the solar system, so that someday – if necessary – humanity may have a shot at destroying or deflecting any space rocks on a collision path with Earth.

For years, work on this kind of infrared telescope had been caught in “NASA mission limbo hell,” MIT astronomer Richard Binzel previously told Insider. Now the project is finally moving forward.

NASA needs a space telescope to defend Earth from city-crushing asteroids

asteroid earth fly by
An artist’s illustration of asteroids flying by Earth.

Experts from around the world practiced for a hypothetical asteroid strike in April. It didn’t go well.

At the Planetary Defense Conference, a group of 200 participants from about two dozen countries worked through a hypothetical scenario in which an asteroid was set to crash into Earth in six months. They determined that no existing technologies could stop the space rock, since the time frame was too short to launch a mission that could destroy or deflect an asteroid.

Without a space telescope like NEO Surveyor, it’s very possible that an asteroid could sneak up on our planet like the one in the April simulation. It has already happened a few times.

In 2013, a house-sized asteroid screamed into the skies above Chelyabinsk, Russia and exploded. The blast sent out a shock wave that broke windows, damaged buildings, and injured more than 1,400 people. No one on Earth saw it coming. That same day, a larger asteroid came within 17,000 miles of the planet.

asteroid russia Chelyabinsk
A house-sized asteroid entered the atmosphere above Chelyabinsk, Russia, in 2013.

Jim Bridenstine, who served as the Trump administration’s NASA Administrator, said in 2019 that the agency’s modeling suggests an event like the Chelyabinsk meteor occurs about every 60 years.

But the Chelyabinsk rock was small – about 50 feet wide. In 2019, a 427-foot, “city-killer” space rock flew within 45,000 miles of Earth, and NASA had almost no warning about that either.

Then last August, an asteroid the size of a car passed closer to Earth than any known space rock had ever come without crashing. It missed our planet by about 1,830 miles. Astronomers didn’t know the asteroid existed until about six hours after it whizzed by. Nobody saw it coming, because it was approaching from the direction of the sun.

Telescopes on the ground can only observe the sky at night, which means they miss almost everything that flies at us from the sun. NEO Surveyor, from its perch in Earth’s orbit, would be able to spot such space rocks. Since it would use infrared light, it could also spot asteroids that are too dark for Earth-based telescopes.

asteroid belt vega
An artist’s concept of an asteroid belt.

Plans for this kind of space telescope have been in the works since 2005, when Congress mandated that NASA find and track 90% of all near-Earth objects 140 meters (460 feet) or larger in size. That’s big enough to obliterate a city like New York.

The initial deadline was 2020. But NASA has only spotted about 40% of those objects so far. NEO Surveyor is designed to bring the agency up to its 90% goal within a decade of launch.

“Every day we wait is one day less that we have the information we need to make a response,” said Binzel, who studies potentially hazardous asteroids. “What that means is, for now, we are relying on luck to keep us safe from major asteroid impacts. But luck is not a plan.”

The NEO Surveyor team is forging ahead – maybe with a budget boost

Mainzer first submitted the idea for an asteroid-hunting space telescope in 2006. NASA declined to take it on as a mission, funding other projects instead. She submitted proposals in 2010 and 2015 as well, but the agency kept passing.

NEO Surveyor finally became an official NASA mission in 2019. Since then, the project has been in what NASA calls “Phase A” – a stage focusing on design and technology development. Now that they’re moving on to Phase B, Mainzer and her team can start building prototypes and developing hardware and software.

They could soon get a major influx of cash, too. NASA’s budget request for 2022 allots $197 million for planetary defense, including $143 million for NEO Surveyor – though Congress must still approve it.

That would be a significant increase from the $28 million the mission received in 2021. NASA Associate Administrator Thomas Zurbuchen estimated in 2019 that developing the telescope could cost about $500 to $600 million in total.

The budget request and Friday’s Phase B approval are “double good news for citizens of planet Earth,” Binzel said, though he added that now, “the ball in squarely in Congress’ court.”

“The clock is ticking,” Mainzer said. “We really want to get off the ground as quickly as possible.”

Aylin Woodward contributed reporting.

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In a NASA simulation of an asteroid impact, scientists concluded they couldn’t stop a space rock from decimating Europe

asteroid earth fly by
An artist’s illustration of asteroids flying by Earth.

Scientists around the world have been bamboozled this week by a fictitious asteroid heading toward Earth.

A group of experts from US and European space agencies attended a week-long exercise led by NASA in which they faced a hypothetical scenario: An asteroid 35 million miles away was approaching the planet and could hit within six months.

With each passing day of the exercise, the participants learned more about the asteroid’s size, trajectory, and chance of impact. Then they had to cooperate and use their technological knowledge to see if anything could be done to stop the space rock.

The experts fell short. The group determined that none of Earth’s existing technologies could stop the hypothetical asteroid from striking given the six-month timeframe of the simulation. In this alternate reality, the asteroid crashed into eastern Europe.

As far as we know, no asteroids currently pose a threat to Earth in this way. But an estimated two-thirds of asteroids 460 feet in size or bigger – large enough to wreak considerable havoc – remain undiscovered. That’s why NASA and other agencies are attempting to prepare for such a situation.

“These exercises ultimately help the planetary-defense community communicate with each other and with our governments to ensure we are all coordinated should a potential impact threat be identified in the future,” Lindley Johnson, NASA’s planetary defense officer, said in a press release.

6 months is not enough time to prepare for an asteroid impact

The fictitious asteroid in the simulation was called 2021PDC. In NASA’s scenario, it was first “spotted” on April 19, at which time it was thought to have a 5% of hitting our planet on October 20, six months after its discovery date.

But Day 2 of the exercise fast-forwarded to May 2, when new impact-trajectory calculations showed that 2021PDC would almost certainly hit either Europe or northern Africa. The participants in the simulation considered various missions in which spacecraft could try to destroy the asteroid or deflect it off its path.

hypothetical impact
The predicted impact region for 2021 PDC on Day 2 of a NASA-led asteroid-impact simulation.

But they concluded that such missions wouldn’t be able to get off the ground in the short amount of time before the asteroid’s impact.

“If confronted with the 2021PDC hypothetical scenario in real life, we would not be able us to launch any spacecraft on such short notice with current capabilities,” the participants said.

They also considered trying to blow up or disrupt the asteroid using a nuclear explosive device.

“Deploying a nuclear disruption mission could significantly reduce the risk of impact damage,” they found.

Still, the simulation stipulated that 2021PDC could be anywhere from 114 feet to half a mile in size, so the chance that a nuke could make a dent was uncertain.

Day 3 of the exercise skipped ahead to June 30, and Earth’s future looked grim: 2021PDC’s impact trajectory showed it headed for eastern Europe. By Day 4, which fast-forwarded to a week before the asteroid impact, there was a 99% chance the asteroid would hit near the border between Germany, the Czech Republic, and Austria. The explosion would bring as much energy as a large nuclear bomb.

All that could be done was evacuate the affected regions ahead of time.

Most asteroids fly under the radar, and many are spotted too late

dinosaur asteroid meteor
An artist’s depiction of the moment the Chicxulub asteroid struck the land that is now Mexico 66 million years ago.

It’s tempting to assume that in the real world, astronomers would spot an asteroid akin to 2021PDC with much more notice than six months. But the world’s ability to surveil near-Earth objects (NEOs) is woefully incomplete.

Any space rock with an orbit that takes it within 125 million miles of the sun is considered an NEO. But Johnson said in July that NASA thinks “we’ve only found about a third of the population of asteroids that are out there that could represent an impact hazard to the Earth.”

Of course, humanity hopes to avoid a surprise like the dinosaurs got 65 million years ago, when a 6-mile-wide asteroid crashed into the Earth. But in recent years, scientists have missed plenty of large, dangerous objects that came close.

comet neowise japan
Comet Neowise appears in the sky over Nayoro, Hokkaido, Japan, July 11, 2020.

Comet Neowise, a 3-mile-wide chunk of space ice, passed with 64 million miles of Earth in July. Nobody knew that comet existed until a NASA space telescope discovered it approaching four months prior.

In 2013, a meteor about 65 feet in diameter entered the atmosphere traveling 40,000 mph. It exploded over Chelyabinsk, Russia, without warning, sending out a shock wave that broke windows and damaged buildings across the region. More than 1,400 people were injured.

asteroid russia Chelyabinsk
The Chelyabinsk meteor streaking across the Russian sky.

And in 2019, a 427-foot-wide, “city-killer” asteroid flew within 45,000 miles of Earth. NASA had almost no warning about it.

That’s because currently, the only way scientists can track an NEO is by pointing one of Earth’s limited number of powerful telescopes in the right direction at the right time.

To address that problem, NASA announced two years ago that it would launch a new space telescope dedicated to watching for hazardous asteroids. That telescope, named the Near-Earth Object Surveillance Mission, along with the European Space Agency’s newly launched Test-Bed Telescope and the Flyeye Telescope that’s being built in Italy, should eventually bolster the number of NEOs we can track.

NASA is testing ways to stymie an asteroid

DART nasa asteroid mission spacecraft
An illustration of the DART spacecraft near an asteroid.

NASA has investigated the options scientists would have if they were to find a dangerous asteroid on a collision course with Earth. These include detonating an explosive device near the space rock, as the exercise participants suggested, or firing lasers that could heat up and vaporize the asteroid enough to change its path.

Another possibility is sending a spacecraft up to slam into an oncoming asteroid, thereby knocking it off its trajectory. This is the strategy NASA is most serious about: Later this year, the agency is scheduled to launch a test of such a technology. The Double Asteroid Redirection Test (DART) will send a spacecraft to the asteroid Dimorphos and purposefully hit it in the fall of 2022.

NASA hopes that collision will change Dimorphos’s orbit. While that asteroid isn’t a threat to Earth, the mission could prove that redirecting an asteroid is possible with enough lead time.

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