ESA challenges amateur astronomers to spot a ‘Christmas’ asteroid
In order to mark the release of ESA’s new asteroid toolkit, the agency is challenging amateur astronomers to spot what it calls a “Christmas” asteroid, according to a press release by the organization published last Friday.
On December 15 at 3:12 a.m. EST (0812 am GMT), the asteroid called 2015 RN35 will come its closest to Earth, passing within around 430,000 miles (686,000 kilometers). But it won’t be easy to spot!
A mighty challenge
“We don’t call this a challenge for no reason. 2015 RN35 will not shine bright in the skies like the star of Bethlehem did millennia ago. No. Smaller than the statue of liberty this asteroid is pretty little on astronomical scales. And as flybys go, at just under two times the distance to the Moon, it’s not likely to make newspaper headlines (although, you never know. Sigh.)” says ESA in their statement.
The agency goes on to say that this is a near-Earth asteroid that fascinates ESA’s Planetary Defence Office in particular because this type of asteroid gives key insights into the composition and trajectory of potentially hazardous objects.
Right now, we don’t know much about the asteroid. “We don’t know what it’s made of or precisely how big it is or if it’s spinning on its axis or even know its orbit particularly well. (Enough to know it won’t strike in the next century!),” adds ESA.

The agency hopes that amateur astronomers will use its asteroid toolkit, created by the Agency’s Near-Earth Object Coordination Centre (NEOCC), based in Rome, to spot the “Christmas” asteroid and identify some of its key features.
Understanding and explaining asteroid populations
“We use these tools every day to plan our observations, to visualize asteroid close approaches and to help us understand and explain the varied asteroid populations in the Solar System and the risk we face,” explains Juan-Luis Cano, Information System Manager at the NEOCC.
“We want them to be as useful to the rest of the world as they are to us, because Planetary Defence is a global effort.”
In addition, ESA hopes to get data on the asteroid from different locations on Earth and find out more about the Apollo group of asteroids it belongs to.
“This is the kind of work ESA’s NEOCC does every day, often with even dimmer asteroids using even larger telescopes, such as the European Southern Observatory’s Very Large Telescope (VLT) and others in the NEOCC’s network of rapid-access telescopes spread all over the globe,” explains Richard Moissl, ESA’s Head of Planetary Defence.
“With these observations, we determine the motion of asteroids and project their path into the future, in order to know if – when – an asteroid could strike. As the recent DART impact showed, and as ESA’s Hera mission will expand on, with enough warning, an asteroid impact is the only natural disaster we can prevent.”