Defending Earth towards harmful asteroids: Q&A with NASA’s Lindley Johnson



It is a cosmic roll of the cube. There isn’t any doubt {that a} main asteroid or comet strike might trigger intensive devastation and profoundly have an effect on life on Earth. 

The biggest hit in current occasions was the thing that exploded over Tunguska, Siberia, in June 1908 with an power influence of 5 to fifteen megatons. Then there was that spectacular and harmful airburst in February 2013 over the Russian metropolis of Chelyabinsk. The Chelyabinsk explosion generated a shock wave that shattered home windows on the bottom, and the ensuing flying glass shards injured greater than 1,000 folks.

Whereas these run-ins are few and much between, these within the know name them wakeup calls.

Infographic: Large Russian meteor blast is greatest since 1908

Thwarting an incoming object that has Earth in its crosshairs will imply deflecting or disrupting the hazardous object. That is a job of planetary protection, an “utilized planetary science” to handle the near-Earth object (NEO) influence hazard.

Lindley Johnson is NASA’s Planetary Protection Officer and program govt of the Planetary Protection Coordination Workplace. An e-mail from him contains the on-the-job line: “Hic Servare Diem,” Latin for “Right here to Save the Day.” caught up with Johnson to debate current occasions and what’s on the planetary-defense agenda within the coming 12 months. What is the influence of the Dec. 1 loss of the Arecibo Observatory’s 305-meter telescope in your planetary radar efforts for NEO observations?

Johnson: The Nationwide Science Basis made the onerous resolution that it wanted to be decommissioned for security causes and introduced down. However the telescope determined to do it by itself. Its planetary radar remark is not distinctive, as we now have it at our Goldstone [Solar System Radar in California’s Mojave Desert] too. What was distinctive about Arecibo was the dimensions of the dish and the ability it generated, which gave it an extended vary than we now have at Goldstone. So we now have misplaced functionality?

Johnson: Now we have misplaced that functionality, however we have not misplaced planetary radar functionality. Nevertheless it does make Goldstone a extra vital functionality for us than it was. We did have some overlap and redundancy previous to lack of Arecibo, however now we now have Goldstone. I believe not solely NASA however different businesses as properly will quickly interact in a research of what’s the future for our planetary radar functionality. I believe the lack of Arecibo will present the inducement to get that collectively, a concerted effort on the a part of a number of businesses.

Associated: Doubtlessly harmful asteroids (photos)

Damage sustained at the Arecibo Observatory 305-meter telescope. The top section of all three of the telescope's support towers broke off. As the 900-ton instrument platform fell, the telescope's support cables also dropped.  Defending Earth towards harmful asteroids: Q&A with NASA’s Lindley Johnson missing image

Injury sustained on the Arecibo Observatory 305-meter telescope. The highest part of all three of the telescope’s assist towers broke off. Because the 900-ton instrument platform fell, the telescope’s assist cables additionally dropped. (Picture credit score: NSF/College of Central Florida) How is the launch subsequent 12 months of NASA’s Double Asteroid Redirection Take a look at (DART) coming alongside?

Johnson: It is about two-thirds of the best way by way of its integration and check now on the Utilized Physics Laboratory [APL, at Johns Hopkins University in Maryland]. It’s starting to appear like an actual spacecraft. However there actually have been challenges with COVID-19 and supply by suppliers of all of the components. One of many remaining massive items nonetheless to be delivered is the rollout photo voltaic arrays. However the integration schedule has been rearranged. Issues are wanting constructive during the testing that is occurring. We’re in fairly good condition to get DART shipped out to Vandenberg [Air Force Base in California] to satisfy the end-of-July launch. Any replace on the Italian Area Company’s Gentle Italian Cubesat for Imaging of Asteroid, the LICIACube constructed to witness DART’s influence?

Johnson: They’ve had their challenges too, perhaps much more so. We’re hoping they are going to have the ability to keep on schedule. LICIACube could possibly be built-in at APL, or it is also built-in out at Vandenberg if they should.

Imagery of the asteroid 2014 JO25,  generated with radar knowledge collected utilizing NASA’s Goldstone Photo voltaic System Radar in California’s Mojave Desert. (Picture credit score: NASA/JPL-Caltech/GSSR) As NASA’s first planetary protection mission, what do you hope to be taught from DART?

Johnson: It should affirm for us what the viability of the kinetic impactor method is for diverting an asteroid’s orbit and decide that it stays a viable choice, no less than for smaller-sized asteroids, that are probably the most frequent influence hazard. You will have been engaged in a collection of “desk prime” workout routines involving the Federal Emergency Administration Company (FEMA) and different organizations in regards to the nature, danger and what to do given an Earth encounter with an asteroid or comet influence. What’s their worth to your work?

Johnson: There will certainly be extra coming, and probably subsequent 12 months. We do introduce completely different eventualities, like how a lot time earlier than influence do you might have? Or what is the measurement of the thing? Up to now, the workout routines have been accomplished with a comparatively small neighborhood. I believe in a future train, our predominant goal is to have a broader neighborhood of the NEO Affect Menace Emergency Protocols Working Group participate, illustration from a lot of different businesses that haven’t been concerned in earlier workout routines. That working group was shaped in early 2019 to work on Objective 5 actions within the Nationwide NEO Technique and Motion Plan.

Creative view of NASA’s Double Asteroid Redirection Take a look at (DART) spacecraft and the Italian Area Company’s LICIACube watchdog previous to influence on the Didymos binary system. (Picture credit score: NASA/Johns Hopkins APL/Steve Gribben) The JPL Heart for NEO Research is NASA’s middle for computing asteroid and comet orbits and their odds of Earth influence. Fireball and bolide knowledge is included on their web site, a few of which is gleaned from categorized army satellites. How is that knowledge change between NASA and the army going?

Johnson: The pathways and the capabilities are extra easy than it was once. We’re nonetheless engaged on making it sooner, extra automated. By this final 12 months a few of it was considerably handbook, with knowledge delayed longer than we want it to be. In case you take a look at the web site, you may see a gentle addition of occasions into our database.

NASA’s proposed NEO Surveyor spacecraft. (Picture credit score: NASA/JPL-Caltech) You’ll wish to receive that knowledge far sooner?

Johnson: Inside hours of the occasion, if not faster. Asteroid samples introduced again to Earth — be they from Japan’s Hayabusa2 spacecraft and NASA’s OSIRIS-REx — how useful are they to your planetary protection workplace?

Johnson: They actually do assist us perceive the character and composition of those objects. Getting these spacecraft on the market to look at them up shut is a part of a step-by-step strategy, from distant sensing of them … after which accumulating a pattern for lab evaluation right here on Earth. It confirms what we expect we find out about an asteroid’s composition. 

That is after all of nice curiosity to the scientific neighborhood. Nevertheless it’s additionally of worth in understanding how mitigation methods is likely to be simpler. For distant sensing of those objects, you’re by no means positive whether or not the traces and squiggles are being interpreted appropriately. Whenever you rise up shut, you may affirm a lot of issues. So it is form of a bootstrap strategy.

Associated: The best asteroid encounters of all time!

This map exhibits reported fireball occasions, with approximate complete optical radiated power and calculated complete influence power for each. (Picture credit score: Alan B. Chamberlin/JPL-Caltech) Any new phrases in your proposed NASA Close to Earth Object Surveyor spacecraft, a space-based infrared telescope able to detecting asteroids near Earth?

Johnson: From a technical standpoint, everyone agrees that this mission is able to transfer on into section B, a preliminary design. The uncertainty proper now could be what the long run funds goes to be. Our planetary protection program doesn’t have ample funds out by way of the variety of years it would take to develop NEO Surveyor as but. Trying again and eyeing the long run, how do you appraise NASA’s planetary protection program? 

Johnson: This system at NASA continues. Utilizing ground-based capabilities in 2020, it appears to be like just like the variety of discovered NEOs goes to hit 2,800 [for the year], a report quantity for us. Most of these are fairly small, a lot smaller than the 140-meter threshold that we’re working towards. 

The extent of which we’re discovering the 140-meter and bigger asteroids stays fairly secure, at about 500 a 12 months. Our projection of the variety of these objects out there’s about 25,000, and we have solely discovered a little bit over one-third of these up to now, perhaps 38% or so. Our fashions inform us we have got about 15,000 extra to seek out. At 500 a 12 months, you do the mathematics, that is 30 years that we now have to get by way of with these form of operations at present. We are able to do it faster. We all know we now have the know-how to do it sooner, and that’s what NEO Surveyor is all about.

Leonard David is creator of the ebook “Moon Rush: The New Area Race,” which was revealed by Nationwide Geographic in Might 2019. A longtime author for, David has been reporting on the house trade for greater than 5 many years. Comply with us on Twitter @Spacedotcom or on Fb. This model of the story revealed on



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