China’s Moon Mission will Probe Cosmic Dark Ages
From Science: On 21 May, China plans to launch a satellite with a vital but unglamorous mission. From a vantage point beyond the moon, Queqiao, as the satellite is called, will relay data from Chang'e 4, a lander and rover that is supposed to touch down on the lunar far side before the end of the year. But a Dutch-made radio receiver aboard Queqiao will attempt something more visionary. In the quiet lunar environment, it will listen to the cosmos at low frequencies that carry clues to the time a few hundred million years after the big bang, when clouds of hydrogen gas were spawning the universe's first stars.
The mission is a proof of principle for other efforts to take radio astronomy above the atmosphere, which blocks key radio frequencies, and far from earthly interference. "Putting the whole show into space is extremely appealing," says Michael Hecht of the Massachusetts Institute of Technology's Haystack Observatory in Westford, whose team is also developing small radio satellites that could be used to probe the cosmos. For Europe's astronomers, it is also a test of cooperation with China, something their U.S. counterparts at NASA are barred from doing.
The Netherlands-China Low-Frequency Explorer (NCLE) project stems from a 2015 Dutch trade mission to China, during which the two countries agreed to collaborate on space missions. The Netherlands is strong in radio astronomy: Its Low-Frequency Array (LOFAR) stretches across much of northern Europe. NCLE Principal Investigator Heino Falcke, of Radboud University in the Netherlands, has long advocated a "LOFAR on the moon." China has an ambitious program of moon missions, so he jumped at the chance to take a first step. "We put together a proposal in 2 weeks," he says. Once funded, the team had just 1.5 years to build the instrument. "Half of the experiment is how you work together" Falcke says. Jinsong Ping of the National Astronomical Observatories of China in Beijing, who leads the Chinese team working on the NCLE, agrees: "It is really challenging both sides. … Different culture, habit, language, working manner."