In late July, a record-setting asteroid hurtled just 40,400 miles over Earth, the largest space rock to come so close in a century. But perhaps more alarming than the flyby itself is how much it caught NASA by surprise, according to internal agency documents obtained by BuzzFeed News.
Spotted just 24 hours before a relatively narrow miss with Earth, the incident reveals holes in NASA’s surveillance network to observe incoming space rocks. The football-field-sized asteroid, dubbed “2019 OK,” is also drawing attention to decades of congressional failures to fix the problem, experts say.
“Because there may be media coverage tomorrow, I'm alerting you that in about 30 mins a 57-130 meter sized asteroid will pass Earth at only 0.19 lunar distances (~48,000 miles),” wrote Lindley Johnson, NASA’s planetary defense officer, in a July 24 email alert sent to other space agency experts. "2019 OK was spotted about 24 hrs ago.”
Flying at nearly 55,000 miles per hour, the asteroid came lumbering by with little warning, first detected that day by a small observatory in Brazil. The flyby came five times closer to Earth than the distance to the moon — a close shave by astronomical standards.
“If 2019 OK had entered and disrupted in Earth’s atmosphere over land, the blast wave could have created localized devastation to an area roughly 50 miles across,” according to a news release sent out by the agency weeks after the flyby. Such an impact has been estimated to happen about once every 3,000 years.
“Our current asteroids search capabilities are not up to the level they should be.”
“This object slipped through a whole series of our capture nets,” Paul Chodas of NASA’s Jet Propulsion Laboratory wrote in an email to his colleagues two days after the July 25 flyby, describing what he called the “sneaky” space rock. “I wonder how many times this situation has happened without the asteroid being discovered at all.”
The emails were obtained in response to a Freedom of Information Act request and provide a detailed, behind-the-scenes look as NASA officials scrambled to figure out why the asteroid wasn’t spotted until it was nearly whizzing past Earth. Other emails show internal agency scientists frustrated by a media response that called the event a “city killer” that “just missed the earth.”
“This one did sneak up on us and it is an interesting story on the limitations of our current survey network,” Johnson wrote in a July 26 email.
The near-miss of the incoming asteroid points to a long-running fight between NASA and Congress to build a reliable way to watch for “potentially hazardous” asteroids. Lawmakers ordered the space agency to detect 90% of hazardous asteroids in a 2005 law, but they haven’t funded telescopes and spacecraft that are large enough to do the job, the US National Academies of Sciences concluded in a June report.
“It's no surprise an object like that would take us by surprise,” MIT planetary scientist Richard Binzel told BuzzFeed News. “Our current asteroids search capabilities are not up to the level they should be.”
The NASA-supported ATLAS telescopes did pick up the asteroid on July 21, days ahead of its close approach, but it was then too obscured by clouds to be identified as a Near Earth Asteroid (NEA) by the space agency. The NASA-funded Pan-STARRS telescopes in Hawaii did see the asteroid even earlier, on June 28 and July 7, but it was then too faint and far away to trigger an alert.
In an interview with BuzzFeed News, Chodas said 2019 OK never posed a threat of impacting Earth.
“The automated systems that calculate trajectories and the chance of impact … worked as designed,” he said. “The issue with 2019 OK was not with [NASA] or the [Minor Planet Center],” but the surveys’ algorithms for identifying dangerous space rocks.
Still, Chodas noted the late discovery was “a surprise to the planetary defense community” and that the event warrants further investigation.
On July 25, NASA officials were prompted to dig deeper for answers after a flurry of alarming news reports surfaced that characterized the asteroid as a “city killer” that “just missed the earth.” The city killer classification rankled NASA officials who traced it back to the Sydney Morning Herald, according to the emails.
The Herald report “quotes the two Australian astronomers - anybody know them? If so, it might be helpful to ask them to think before they speak” of things like “nuclear explosions,” says a July 27 email sent to Chodas and Johnson, the planetary defense officer (the sender’s name was redacted). “I don't know whether the Sydney reporter reached out to them or whether they reached out to him. All the rest - including WaPo -- is simply repetition … This story also says to me that we have to keep up our good work of calming down asteroid rhetoric - city-killers, nukes, etc. I will reach out as well.”
The email evoked a blunt reply from Lindley.
“What makes this especially galling is that the Australian are doing essentially nothing to support Planetary Defense,” he said.
More than half of the emails turned over to BuzzFeed News contain other detailed complaints from NASA officials about news coverage of the “near miss,” with particular scorn directed at Epoch Times, The Washington Post, and The Hill over their “lazy journalism.” The emails include two harshly critical letters to the Post and Hill about its coverage and the importance of reaching out directly to NASA experts for accurate information instead of interviewing a “random astronomer or, worse, Voldemort.”
“An asteroid can't be a ‘city killer’ when it flies by Earth at 70,000 km, and if and when an asteroid impact might occur, it would not release any nuclear radiation. (- no wonder you went ballistic when you saw this ....)," says the July 27 email from the unnamed NASA official.
Other emails suggest that some within the space agency saw the flyby as clear evidence of the need for better detection. An email sent to Lindley and Kelly Fast, the Near-Earth Object Observation Program Manager in NASA's Planetary Defense Coordination Office, said “a spectacularly important lesson here” is that the ATLAS telescope and the PAN- STARRS observatory “need to detect slower objects.”
“The raison d'etre for ATLAS is detecting imminent impactors,” says the email, whose sender NASA redacted before sending to BuzzFeed News. “It looks like some impactors are too slow to be found easily. It is fairly disturbing to me that this object was undetectably slow for nearly 2 weeks!”
Binzel and other outside experts suggest the real lesson of 2019 OK is that Congress should fund a dedicated surveillance satellite, now awaiting $40 million to go ahead with its design, equipped with an infrared telescope to spot incoming asteroids without facing the hassles of weather, the moon, or peering through the obscuring atmosphere like telescopes on the ground.
“It is fairly disturbing to me that this object was undetectably slow for nearly 2 weeks!”
“Infrared surveying from space sounds good to me in order to keep our world safe — or at least to worry legitimately when killer asteroids approach with such short notice that there is nothing we can do,” Williams College astronomer Jay Pasachoff told BuzzFeed News. Ideally, he added, such a spacecraft would detect dangerous asteroids decades ahead of time so they could be deflected.
The House Science Committee, which learned about the asteroid from news reports, is still developing the law that could authorize NASA to build an asteroid-spotting satellite, a majority staffer, who would only discuss the issue on background, told BuzzFeed News.
“What the bill will include on the topic of NEOs is still to be determined,” the staffer said, noting that the committee has taken a number of steps since 1990, including drafting policy, “that led to NASA’s surveys to detect, track, catalog, and characterize NEOs and the potential threat they pose, as well as potential options for protecting Earth from hazardous NEOs.”
Last year, the White House’s Office of Science and Technology Policy unveiled an NEO action plan, a set of guidelines that federal government agencies are supposed to follow to confront the threat posed by near-arth objects over the next 10 years. But the report does not explain how the agencies can successfully execute its mission, nor does the report call on Congress to earmark additional funding to support the effort.
A recent poll conducted by the Associated Press and the NORC Center for Public Affairs Research shows that near-Earth objects have captured the attention of the public, who are far more interested in seeing NASA focus on potential impacts than sending astronauts to the moon or Mars.
Despite NASA officials’ attempts to calm the public and rein in the media's fearmongering of the asteroid, according to the emails, some of the scientists were excited when they discovered how significant 2019 OK was.
“BTW, all, just for context, it appears that 2019 OK is by far the largest asteroid to pass this close to Earth in the last century!” Lindley, the NASA planetary defense officer, wrote in a July 28 email to Chodas, Fast, and other NASA officials under the subject line “Unhappy about Washington Post story.”
“Nothing this big is predicted to pass this close again until Apophis on 2029,” he said. ●
https://www.buzzfeednews.com/article/danvergano/nasa-emails-asteroid-2019-ok
2019-09-19 15:03:00Z
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