Speed Demon Asteroid Sprints Safely Past Earth Today

Asteroid 2014 RC photographed 30 minutes before closest approach to Earth today. During this one-minute-long time exposure the asteroid covered more than 3/4 degree of sky. Credit: Ernesto Guido, Nick Howes, Martino Nicolini

Earth-approaching asteroid 2014 RC ripped pass Earth today, got its orbit refashioned by our planet’s gravity and now bids us adieu. I thought you’d like to see how fast this ~60-foot-wide (20-meter) space rock moved across the sky. The team of observers at Remanzacco Observatory in Italy  photographed it remotely with a telescope set up in Australia. 30 minutes before closest approach to Earth of 25,000 miles (40,000 km), 2014 RC was traveling at the rate of 49.5 arc minutes (1.6 times the diameter of the full moon) per minute.

2014 RC accelerates across the sky from 4 a.m. to 4 p.m EDT in this path created by Gianluca Masi using SkyX Pro software and the latest positions from JPL.
2014 RC accelerates across the sky from 4 a.m. to 4 p.m EDT in this path created by Gianluca Masi using SkyX Pro software and the latest positions from JPL. he asteroid’s intrinsic speed was not exceptional, but because it came so close to Earth, it covered a huge swath of sky in a hurry.

At the time, the asteroid glowed at magnitude +11.2, bright enough to see in a 4.5 inch telescope even in the bright moonlit sky at the time. Let’s try to get a feel for its speed. Just to keep 2014 RC centered in the field of view, you’d have to continually move the telescope to follow it as it you were tracking an airplane or satellite. What a thrill it must have been for observers in Australia and New Zealand who got the ride of their life across the heavens hanging onto this fleet rock with their eyeballs. In an hour’s time, centered on closest approach, the asteroid traveled approximately 48º. That more than twice the length of the constellation Orion!

The orbit of 2014 RC occasionally brings it close to Earth as it did today September 7, 2014. Credit: NASA/JPL-Caltech
The orbit of 2014 RC occasionally brings it close to Earth as it did today September 7, 2014 when it passed less than 1/10 the distance of the moon to the Earth. The asteroid orbits the sun every 1.5 years. Credit: NASA/JPL-Caltech

As  2014 RC blew by, its orbit was bent by Earth’s gravity and sent on a new trajectory. If this sounds familiar, we deliberately performed the same maneuver with the Voyager I and II spacecraft back in the late 1970s and early 1980s. A rare planetary alignment allowed scientists to swing the probes near Jupiter and Saturn to gain speed and shape their orbits for future encounters. Such gravity assist maneuvers are now commonplace.

The dot behind the hubbub. Gianluca Masi, who runs the Virtual Telescope Project, tracked 2014 RC during his time exposure, so it shows up as a tiny dot instead of a streak. Credit: Gianluca Masi
Space rock exposed! Gianluca Masi, who runs the Virtual Telescope Project, tracked 2014 RC during his time exposure, so it shows up as a tiny dot instead of a streak. Credit: Gianluca Masi

No doubt 2014 RC will approach Earth again, but no threatening encounters are in the cards for at least 100 years. For now we’re grateful it passed safely while inspiring wonder at what the solar system can throw at us.

Update: here’s an additional set of images from Peter Lake from Australia. You can see more on his blog here.

Three 30 second exposures at different times during Asteroid 2014 RC's pass by Earth on September 7, 2014. Credit and copyright: Peter Lake.
Three 30 second exposures at different times during Asteroid 2014 RC’s pass by Earth on September 7, 2014. Credit and copyright: Peter Lake.

Get Ready for Sunday’s Close Flyby of Asteroid 2014 RC

This graphic depicts the passage of asteroid 2014 RC past Earth on September 7, 2014. At time of closest approach, the space rock will be about one-tenth the distance from Earth to the moon. Times indicated on the graphic are Universal Time. Subtract 4 hours for Eastern Daylight Time. Credit: NASA/JPL-Caltech

Guess who’s dropping by for a quick visit this weekend? On Sunday, a 60-foot-wide (20-meters) asteroid named 2014 RC will skim just 25,000 miles (40,000 km) from Earth. That’s within spitting distance of all those geosynchronous communication and weather satellites orbiting at 22,300 miles. 

Size-wise, this one’s similar to the Chelyabinsk meteorite that exploded over Russia’s Ural Mountains region in February 2013. But it’s a lot less scary. 2014 RC will cleanly miss Earth this time around, and although it’s expected back in the future, no threatening passes have been identified. Whew!

2014 RC will pass along the outer edge of the geosynchronous satellite belt, home to many weather and communications satellites. The chance of a hit is close to infinitesimal. Click for more information and detailed finder charts. Credit: SatFlare
2014 RC will pass along the outer edge of the geosynchronous satellite belt, home to many weather and communications satellites. The chance of a hit is close to infinitesimal. Click for more information and detailed finder charts. Credit: SatFlare

NEOs or Near Earth Asteroids are defined as space rocks that come within about 28 million miles of Earth’s orbit. Nearly once a month astronomers discover an Earth-crossing asteroid that passes within the moon’s orbit.  In spite of hype and hoopla, none has threatened the planet. As of February 2014, we know of 10,619 near-Earth asteroids. It’s estimated that 93% of all NEOs larger than 1 km have been discovered but 99% of the estimated 1 million NEOs 100 feet (30-meters) still remain at large.

No surprise then that new ones pop up routinely in sky surveys. Take this past Sunday night for example, when the Catalina Sky Survey nabbed 2014 RA, a 20-foot (6-meter) space rock that whistled past Earth that evening at 33,500 miles (54,000 km). It’s now long gone.

Artist view of an asteroid (with companion) passing near Earth. Credit: P. Carril / ESA
Artist view of an asteroid (with companion) passing near Earth. Credit: P. Carril / ESA

2014 RC was picked up on or about September 1-2 by both the Catalina Sky Survey and Pan-STARRS 1 survey telescope atop Mt. Haleakala in Maui. The details are still being worked out as to which group will take final discovery credit. Based on current calculations, 2014 RC will pass closest to Earth around 2:15 p.m. EDT (18:15 UT) on Sunday, September 7th. When nearest, the asteroid is expected to brighten to magnitude +11.5 – too dim for naked eye observing but visible with a good map in 6-inch and larger telescopes.

Seeing it will take careful planning. Unlike a star or planet, this space rock will be faint and barreling across the sky at a high rate of speed. Discovered at magnitude +19, 2014 RC will brighten to magnitude +14 during the early morning hours of September 7th. Even experienced amateurs with beefy telescopes will find it a challenging object in southern Aquarius both because of low altitude and the unwelcome presence of a nearly full moon.


64-frame movie showing Toutatis tumbling through space only 4.3 million miles from Earth on Dec. 12-13. Credit: NASA/Goldstone radar

Closest approach happens in daylight for North and South America , but southern hemisphere observers might spot it with a 6-inch scope as a magnitude +11.5  “star” zipping across the constellations Pictor and Puppis. 2014 RC fades rapidly after its swing by Earth and will quickly become impossible to see in all amateur telescopes, though time exposure photography will keep the interloper in view for a few additional hours.

2014 RC accelerates across the sky from 4 a.m. to 4 p.m EDT in this path created by Gianluca Masi using SkyX Pro software and the latest positions from JPL.
2014 RC accelerates across the sky between 4 a.m. to 4 p.m EDT September 7 in this path created by Gianluca Masi using SkyX Pro software and the latest positions from JPL.

Most of us won’t have the opportunity to run outside and see the asteroid, but Gianluca Masi and his Virtual Telescope Project site will cover it live starting at 6 p.m. EDT (22:00 UT). Lance Benner, who researches radar imaging of near-Earth and main-belt asteroids, hopes to image 2014 RC with 230-foot (70-m) radar dish at the Goldstone complex on September 5-7 and possibly the big 1,000-foot (305-m) radar dish at Arecibo. Both provide images based on radar echoes that show asteroids up close with shapes, craters, ridges and all.