A 'Double Planet' Seen From Mercury

Image credit: NASA

Analysis by Ray Villard, for Discovery News

I never cease to be humbled and amazed when I see our Planet Earth reduced to a pinpoint when photographed from elsewhere in the solar system. So far, our planet-roaming spacecraft have taken tourist snapshots of Earth as seen from Mars, Saturn, and beyond Pluto’s obit.

But this latest view from NASA’s MESSENGER (MErcury Surface, Space ENvironment, GEochemistry and Ranging) spacecraft is a jaw-dropper.

If in some parallel universe Mercury had intelligent life, its science equivalent of Galileo would have cataloged Earth as a “double planet,” because our moon is so comparatively large next to Earth.

In fact, recent news from NASA's Lunar Reconnaissance Orbiter shows that the moon is a geologically active world. Call it a “satellite planet” -- a teasing oxymoron introduced by Pluto explorer Alan Stern.

In fact this kind of humbling photograph makes the debate over planet-size -- as in the case of the Pluto hysteria – seem irrelevant. Face it, we like on a speck of cosmic dust.

Views like this momentarily lift us from the gravitational pull of our warlike species. It makes all of our political fights, conflicts and upheavals seem puny and irrelevant against the velvet black backdrop of a star sprinkled infinite universe. You might imagine such a view from standing alongside the thrones of mythological gods.

The snapshot was not taken for inspiration but for science. It’s part of MESSENGER's campaign to search for vulcanoids. These aren't Mr. Spock mutants, but small rocky objects that might exist in orbits between Mercury and the Sun.

Carl Sagan was first taken aback by the distant Earth perspective when the Voyager 1 spacecraft photograph Earth from 3.7 billion miles away in 1990. He was inspired to write the 1994 book, “Pale Blue Dot: A Vision of the Human Future in Space.”

Ok, so what if Earth is just a dot in the picture? Well, it’s incredible to think that dot encompasses all the achievements, joys, fears, and tears of the 100 billion people who have occupied this celestial pebble since the dawn of our species.