Making a hot planet cool

SCIENTISTS HOPING #UNVEILVENUS CAMPAIGN WILL CONVINCE NASA TO LAUNCH FIRST DEDICATED VENUS MISSION SINCE MAGELLAN’S 1989 VOYAGE.

It’s been more than a quarter century since NASA last launched a dedicated Venus mission, the Magellan radar mapper. Could the key to winning funding for a new mission be… a hashtag? Well, it can’t hurt.

“We’re trying to sort of rebrand ourselves, so you may have seen the hashtag going around, #UnveilVenus,” said Bob Grimm, chairman of the Venus Exploration Analysis Group (VEXAG), speaking Nov. 29 at the group’s annual meeting at NASA Headquarters. “We’re trying to ‘social media-ize’ this and get more discussion going on about Venus.”

Odds are that you hadn’t seen that hashtag going around: a Twitter search at the time of his talk turned up only one tweet that used it, from VEXAG’s own account, and just a handful since. The good news for Venus scientists is that, regardless of their social media strategy, there is growing optimism that NASA will return there, sooner or later.

The sooner could be quite soon. Two of the five finalists in the ongoing competition in NASA’s Discovery program are Venus missions. VERITAS, the Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy mission, is an orbiter that would provide high-resolution maps of the planet’s surface and information about its composition. DAVINCI, the Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging, would study the composition of the planet’s dense atmosphere during an hour-long descent.

Jim Green, director of NASA’s planetary science division, said at the VEXAG meeting the selection of one or possibly two proposals for development is on schedule. “There’s an excellent chance we’ll be able to complete the selection and make that announcement before the end of December,” he said.

In January, NASA plans to release the announcement of opportunity for the next mid-sized New Frontiers mission. Among the six categories of missions eligible for this competition is Venus In Situ Explorer, which would study the planet’s atmosphere and surface. Initial proposals are due to NASA 90 days after the announcement’s release, and the agency expects to select several for additional study by next November, with a final decision coming in May 2019.

Scientists aren’t counting on just those competitions. There is cooperation with Japan’s Akatsuki spacecraft, which entered orbit around Venus nearly a year ago after an engine malfunction prevented an earlier orbit insertion attempt. There are plans to take advantage of upcoming NASA and ESA spacecraft flying by Venus on gravity-assist maneuvers, efforts which require negotiations to turn on instruments that would otherwise be inactive during the flybys.

There are also discussions with Russia about participation in Venera-D, an ambitious Venus mission planned for the mid-2020s. Green said any cooperation has been difficult because of the “cool relationship” between the U.S. and Russia, but he did win approval for bilateral discussions with Roscosmos in October. That meeting led to a decision to extend a joint study on ways the two space agencies could cooperate on the mission.

That renewed interest in Venus missions, and the “rebranding” Grimm mentioned, is linked in large part to what’s known as comparative planetology. Venus is nearly the same size as the Earth, yet a very different world. “Why is our sister planet so different?” Grimm asked. Understanding what happened to Venus might provide insights to Earth’s future as well.

NASA Chief Scientist Ellen Stofan, who previously was deputy project scientist on Magellan, offered words of encouragement to her fellow Venus scientists. “I always reflect on the fact that we’re kind of the Galaxy Quest of scientists: Never give up, never surrender,” she said at the VEXAG meeting. “We’re hanging in there because we are always drawn back to Venus, because it is so significant.”

Just don’t forget the hashtag.