NASA kicked off the new year with a pair of probes circling the moon in the latest mission to understand how Earth’s closest neighbour formed.
The action began on New Year’s Eve when Grail-A swung over the south pole, fired its engine and braked into orbit around the moon. Not to be outdone, its twin Grail-B executed the same manoeuvres on New Year’s Day.
The arrivals capped a roundabout journey spanning 3 1/2 months and covering 2 1/2 million miles (4.02 million kilometres).
Since the washing machine-size Grail probes short for Gravity Recovery And Interior Laboratory were squeezed on a small rocket to save on costs, it lengthened the trip and took them 30 times longer to reach the moon than the Apollo astronauts, who took a direct three-day flight.
Previous spacecraft have attempted to study the moon’s gravity about one-sixth Earth’s pull with mixed success. Grail was expected to give scientists the most detailed maps of the moon’s uneven gravitational field and insight into its interior down to the core.
Data collection won’t begin until March after the near-identical spacecraft refine their positions and are circling just 34 miles (54.72 kilometres) above the surface. While scientists focus on gravity, middle school students will get the chance to take their own pictures of the moon using cameras aboard the probes as part of a project headed by Sally Ride, the first American woman in space.
There’s already chatter about trying to extend the $496 million mission, which was slated to end before the partial lunar eclipse in June.
