Laser-blasting System Could Vaporize Big Asteroids

DE-STAR, a proposal to blow up asteroids as they bear down on Earth. Credit: Philip M. Lubin

The uncanny — but unrelated — combination of today’s close flyby of Asteroid 2012 DA14 and the meteor that created an airburst event over Russia has many wondering how we could deal with future potential threats to Earth from space. A group of researchers are hoping to aim a laser-blasting vaporizer in its direction and blow it away.

Dubbed DE-STAR, or Directed Energy Solar Targeting of Asteroids and exploRation, the theoretical orbital system is designed to convert the sun’s energy into laser blasts that would annihilate any cosmic intruders bearing down on Earth.

Although the system sounds like a plot from a science fiction movie, the researchers — led by scientists at two California universities — maintain that it is built on sound principles.

“This system is not some far-out idea from Star Trek,” stated Gary Hughes, a researcher and professor from California Polytechnic State University, San Luis Obispo, in a press release.

“All the components of this system pretty much exist today. Maybe not quite at the scale that we’d need – scaling up would be the challenge – but the basic elements are all there and ready to go. We just need to put them into a larger system to be effective, and once the system is there, it can do so many things.”

Construction details were not clear in a press release advertising DE-STAR, but the researchers describe astonishing results from even a modest-sized version of the system.

DE-STAR was modeled at several different sizes. At 328 feet (100 meters) in diameter, which is double the International Space Station’s size, it could “start nudging comets or asteroids out of their orbits,” Hughes stated.

A 6.2 mile (10-kilometer) DE-STAR version could send 1.4 megatons of energy daily to the marauding asteroid, providing enough juice every year to kill a space rock as big as 1,640 feet (500 meters) across. (That’s more than 10 times the size of 2012 DA14, which came within 17,200 miles of Earth Feb. 15.)

“Our proposal assumes a combination of baseline technology –– where we are today –– and where we almost certainly will be in the future, without asking for any miracles,” added Philip Lubin, who is with the University of California, Santa Barbara.

Besides asteroid annihilation, DE-STAR could give a fuel boost to long-distance space travellers.

A proposed DE-STAR 6 (size not disclosed) is advertised as able to push “a 10-ton spacecraft at near the speed of light, allowing interstellar exploration to become a reality without waiting for science fiction technology such as ‘warp drive’ to come along.”

The press release did not reveal a budget for any version of the DE-STAR, how it would be constructed, or how quickly the system could begin fencing with asteroids.

Researchers emphasized, however, that system proposals such as theirs must be taken seriously to ward off incoming space rocks.

“We have to come to grips with discussing these issues in a logical and rational way,” stated Lubin.

“We need to be proactive rather than reactive in dealing with threats. Duck and cover is not an option. We can actually do something about it and it’s credible to do something. So let’s begin along this path. Let’s start small and work our way up. There is no need to break the bank to start.”

Source: UCSB

Asteroid 2012 DA14: Observing Prospects and How to See It

Image credit: NASA/JPL-CALTech

Mark your calendars: this Friday, February 15, 2013, is the close flyby of Near Earth Asteroid 2012 DA14, passing just 27,630 kilometers (17,168 miles) from the surface of the Earth. About 50 meters (164 feet) in size, 2012 DA14 and its close shave marks the the first time there has been passage of an asteroid this close that we’ve known a year beforehand. Yes, it passes within the ring of geosynchronous satellites girdling the Earth. No, there’s no danger, either to said satellites or the Earth, so Bruce Willis can stay home for this one.  But right behind those inquiries, the question we most frequently get is… how can I see it?

The orbital path of asteroid 2012  DA14 as seen face on (top) & near edge on (bottom). (Credit: JPL Small Body Database Browser).
The orbital path of asteroid 2012 DA14 as seen face on (top) & near edge on (bottom). (Credit: JPL Small Body Database Browser).

The great news is that an advanced observer can indeed catch 2012 DA14 on its close pass the night of February 15th… with a little skill and luck. Now for the bad news; the asteroid won’t be visible without binoculars or a telescope, and North America will largely miss out.

2012 DA14 will be really moving across the sky on closest approach, covering 0.8° per minute, or the diameter of a Full Moon every 45 seconds!  With its passage closer to the Earth than the ring of geosynchronous satellites, it’s worth treating the passage of the asteroid as a satellite and hunting it down accordingly. Catching and watching such a pass can be an unforgettable experience; not many objects in the sky show such swift motion in real time. In fact, 2012 DA14 will span the celestial sphere from declination -60° to +60° in just 4 hours!  Needless to say, its passage through the Earth’s gravity well will alter its orbit considerably; most planetarium software programs do not account for this and thus will introduce a large error for a heliocentric object. Compounding the dilemma is the large amount of parallactic shift of such a nearby object. As viewed from the span of the Earth, 2012 DA14 will have a parallax of ~20° at greatest approach!

The path of asteroid 2012 DA14 through the celestial sphere on February 15th. (Created by Author).
The path of asteroid 2012 DA14 through the celestial sphere on February 15th. (Created by Author).

But two sites on the web can help you with the search. One is Heavens-Above,  which currently has a link on its main page to custom generate sky charts for specific locations for 2012 DA14 (make sure you’re logged in as a registered user and your observing location is set correctly). Another option is to generate an ephemeris customized for your location from the JPL Solar System Dynamics Horizons Web-Interface.

Asteroid 2012 DA14 is approaching the planet Earth from “down under,” and moving almost exactly parallel to the 12 hour line in right ascension. In fact, it’ll cross very near the equinoctial point in Virgo (one of the two points where the celestial equator and the ecliptic cross) shortly after its closest approach on Friday, February 15th at 19:25UT. The asteroid will be at the local zenith (straight overhead) for observers in the pre-dawn hours located in western Indonesia at closest approach. Australia and eastern Asia will have a shot at seeing the asteroid as it whizzes through the sky in the early morning hours of February 16th local. Observers in western Asia, Africa and Europe will see the asteroid lower to the east on the night of the 15th. Note that 2012 DA14 juuuuuust misses Earth’s shadow (see strip chart) at closest approach. The shadow of our fair planet is ~20° across at the distance of the geosynchronous satellites; had it passed about a month later, we would have seen an “asteroid eclipse!” In fact, “eclipse season” for geosynchronous satellites occurs right around the equinoxes and is only a month away.

The “banana strip chart” shows the path of 2012 DA14 from the time it reaches a magnitude brighter than +10 at 17:40UT until it dips back down below it at 22:10UT on the same night. It also shows the width of uncertainty for its position due to the aforementioned 20° of parallax, and the points that it enters and departs the distance sphere of the geosynchronous satellites. Keep in mind, these satellites still orbit roughly hundred times higher than the International Space Station!

A good search strategy to catch 2012 DA14 is to actually to treat it like you’re hunting for a faint satellite. Find the time that it’s crossing a set declination and begin scanning with binoculars in right ascension back and forth until you “ambush” your astronomical prey moving slowly against the starry background. If using a telescope, use the lowest power and widest field of view that the instrument will allow. We’ve used this technique in the past to sweep up Near Earth Asteroids 2005 YU55 and 99942 Apophis and routinely use it to hunt for satellites fainter than naked eye visibility. At closest approach, asteroid 2012 DA14 will shine at around +8th magnitude as it crosses the Bowl of Virgo northward past Denebola in the constellation Leo.

Recent measurements early this month conducted by astronomers at the Las Campanas observatory in Chile refined the orbit of 2012 DA14, placing its February 15th passage just 45 kilometres closer to Earth than previously calculated but still well outside the threat zone. Campaigns are underway to refine measurements of its orbit even further on this pass. We won’t get another close pass of 2012 DA14 until February 16th, 2046 when the asteroid misses us at about twice the distance of the Moon. An impact has been ruled out for this century. Predictions get less certain the further you project them into time, and 2012 DA14 will definitely be a space rock worth keeping tabs on!     

In Two Weeks This 50-Meter Asteroid Will Buzz Our Planet

 Asteroid 2012-DA14 will pass Earth closely on Feb. 15, 2013 (NASA)

On February 15 a chunk of rock about 50 meters wide will whiz by Earth at nearly 8 km/s, coming within 27,680 km of our planet’s surface — closer than many weather and communications satellites.

For those of you more comfortable with imperial units, that’s 165 feet wide traveling 17,800 mph coming within 17,200 miles. But regardless whether you prefer meters or miles, in astronomy that’s what’s called a close call.

Scientists stress that there’s no danger of an impact by this incoming asteroid, designated 2012-DA14, but it’s yet another reminder that in our neck of the Solar System we are definitely not alone.

“2012-DA14 will definitely not hit Earth,” says JPL’s near-Earth object specialist Don Yeomans. “The orbit of the asteroid is known well enough to rule out an impact.”

But with 2012-DA14’s upcoming February flyby Yeomans notes, “this is a record-setting close approach.”

The rocky asteroid will come within about 4 Earth radii, which is well within the orbits of geosynchronous satellites. During its closest approach at 19:26 UTC it should be visible in the sky to amateur telescopes (but not the naked eye), becoming as bright as an 7th- or 8th-magnitude star.


Radar observatories will be watching 2012-DA14 during the days leading up to and following its approach in an attempt to better determine its size, shape and trajectory. NASA’s Goldstone facility will have an eye — er, dish — on DA14, but it won’t be visible to Arecibo. Stay tuned for more info!

Read more about 2012-DA14 on the JPL Near-Earth Object Program page here.