Bill Dunford • Dec 02, 2013
Somewhere Over the Bay of Rainbows
China's first lunar lander, which also happens to be humankind's first in nearly four decades, is on its way to the Moon. The Chang’e 3 spacecraft departed Earth on December 2 local China time, carrying the Yutu (Jade Rabbit) rover.
Chang’e 3 is headed for a mid-December landing on a broad plain called Sinus Iridum, "The Bay of Rainbows." Sinus Iridum is found at the northwest edge of Mare Imbrium, or "Sea of Rains." It's an impact basin a couple of hundred kilometers wide that was filled in by floods of basaltic lava. At its "shores" is a semi-circular ring of dramatic mountains called Montes Jura, with the Heraclides Promontory at its western tip and the Laplace Promontory at the eastern tip.
This area is over 1,000 kilometers from the nearest Apollo landing site, and it could provide lunar explorers with a rich set of information about the Moon and its history.
Thanks to NASA's Lunar Reconnaissance Orbiter, we can make an advance visit of our own. Following are a few extreme close-ups of the Bay of Rainbows, courtesy of LRO's sharp-eyed cameras, which can make out objects as small as the equipment left of the surface by the Apollo astronauts, and even their foot trails.
One of the first things that becomes apparent when looking through LRO's Sinus Iridum data is that this plain, which looks so smooth from a distance, is a little more...complicated than you might think. I purposely chose the most featureless section of the bay that I could see, and found that images from this area typically look like the following.
There will be no shortage of rocks and craters for Yutu to explore.
Here's one interesting crater among many, an apparently (relatively) young example with bright ejecta and what looks like rings of melted rock.
If the Jade Rabbit wandered far enough to reach the edge of the bay, it would be able to explore Promontorium Laplace, a cape marked by mountains that rise as much as 2600 meters above the lava plains. It was named for Pierre Simon marquis de Laplace, who was a French astronomer in the 18th century.
Here's a close look at the exact point where the plains meet the Laplace headlands and its intriguing geology.
Imagine the view from on top of the hill!
If the Chang'e 3 landing goes well, we won't have to imagine the view from the plains, as we follow along with Yutu's adventures on the surface of the Moon.