Space Agency Issues Challenge: Find the Christmas Asteroid

Christmas is coming early for amateur astronomers. On Dec. 15, the so-called Christmas Asteroid will swing by our little blue marble, coming within 1.8 lunar distances (679,800km).

To celebrate the occasion — and to promote the launch of its nifty free-to-use asteroid toolkit — the European Space Agency (ESA) issued a challenge to amateur stargazers.

Find the Christmas Asteroid, and share your observations with the world.

a graphic giving key details on the Christmas asteroid

Graphic: ESA


Telescope needed

The ESA reports that stargazers in the Southern Hemisphere have the best chance of glimpsing the Christmas Asteroid from Dec. 15-17. But you’ll need a telescope of at least 30cm or larger because the Christmas Asteroid (officially dubbed 2015 RN35) has a visual magnitude below 14. For context, the former planet Pluto has a visual magnitude of 14.

Similarly equipped European observers might be able to spot the astronomical treasure from Dec. 17 to 19.

If you do happen to lay eyes on the festive space rock, the ESA requests that you share your data and location with the hashtag #ESAChristmasAsteroid. The agency will then repost your discovery on its social media channels.

“This is the kind of work [we do] 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,” said Richard Moissl, ESA’s Head of Planetary Defence, in a blog post.

A haystack in space

Why is the ESA crowdsourcing this astronomical scavenger hunt? Well, the answer is that space is very, very big, and there are quite a few asteroids perpetually looping through our solar system. Keeping track of everything zooming around out there is kind of like finding a needle in a haystack — if the haystack were floating in a vast, functionally eternal emptiness.

According to the ESA, almost 98 percent of the estimated 930 extinction-event-sized asteroids (size 1,000m and greater) in our solar system are accounted for. By contrast, space agencies don’t know the orbits of virtually any of the approximately 50 million one-metre asteroids that whiz by us regularly. But that’s okay because those pint-sized pebbles hit the planet about once every two weeks, and almost no one ever notices.


The problem lies with midsized ones, which includes the Christmas Asteroid. These range from 10 to 1,000m and could easily destroy a city. The Tunguska asteroid that struck Eastern Siberia in 1908 was between 30m and 40m. It leveled 80 million trees over a 2,150 square-metre area.

The more mid-sized asteroids that scientists identify and begin tracking, the greater the chances a city in the path of such an event might be evacuated. Scientists estimate they’ve discovered roughly 18 percent of asteroids this size. To help make sense of all this, the ESA created this graphic, which manages to be both reassuring and disturbing in equal measure.

a graphic describing how many dangerous asteroids in our solar system have been discovered.

Whether this graphic makes you feel safe or in danger likely depends on your general outlook on life. Graphic: ESA


No chance of impact

The Christmas Asteroid is between 60 and 140m, meaning an impact from it would be quite significant. But never fear. The ESA says there’s a zero percent chance it will hit our planet in the next 100 years and stresses that two lunar distances isn’t all that close as far as asteroids are concerned.

Adorably, the agency hopes the media won’t sensationalize the event.

“And as flybys go, at just under two times the distance to the Moon, it’s not likely to make newspaper headlines,” wrote an unnamed perpetual optimist in an ESA blog post.

Well, one can hope.

Andrew Marshall

Andrew Marshall is an award-winning painter, photographer, and freelance writer. Andrew’s essays, illustrations, photographs, and poems can be found scattered across the web and in a variety of extremely low-paying literary journals.
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