Robert Herrick hopes to learn why Earth’s nearest neighbor and one of the brightest objects in the night sky, Venus, has mountains “and other evidence of horizontal movement of the surface” but not plate tectonics like we have on Earth.
The University of Alaska Fairbanks researcher is part of a team of scientists who will work on NASA’s next Discovery Program mission, with launch as soon as 2028, mapping the surface of Venus and creating 3D reconstructions of the planet’s topography.
Similar in size to Earth, Venus’ dense atmosphere of mostly carbon dioxide is laced with clouds of sulphuric acid obscuring its surface.
The goal of the $500 million mission as described in NASA’s announcement last week is “to understand how Venus became an inferno-like world when it has so many other characteristics similar to ours — and may have been the first habitable world in the solar system, complete with an ocean and Earth-like climate.”
Herrick will review data from project VERITAS — Venus Emissivity, Radio Science InSAR, Topography and Spectroscopy — as it comes in and figure out how to catalog it for the coming decades of inquiry.
The astronomy community “kind of lost it,” after NASA Administrator Bill Nelson announced on Wednesday that the agency, after sending more than a dozen robots to Mars, was finally giving Venus a turn, according to Marina Koren, who covers space exploration for The Atlantic magazine.
“There’s a spacecraft in orbit around Venus now — a Japanese spacecraft called Akatsuki — but NASA hasn’t sent a mission to the planet in more than 30 years,” Koren wrote.
Venus is thought to have had “an ocean’s worth of water” and some scientists see evidence that it was habitable during most of the history of the solar system, according to Herrick.
“Understanding how Venus and Earth ended up so different from similar starting conditions is critical for assessing the odds that Earth-sized and Earth-distance around other stars will mean Earth-like conditions for potential life,” Herrick wrote in an email.
He described what makes Venus’ geology interesting.
“Ultimately, much of what we think of as geologic activity, like volcanism and mountain building, is a manifestation of a planet cooling and releasing heat to outer space,” Herrick said.
“Mars, Mercury and the moon formed an outer rigid shell where occasionally volcanism poked through, but otherwise the surface does not move around much,” he said. “Earth, on the other hand, has a surface with mostly rigid plates moving around relative to each other, with lots of hot material being brought to the surface to cool at mid-ocean ridges.
“From past missions, we know that Venus has mountain ranges and other evidence of horizontal movement of the surface, but it does not currently have plate tectonics. It may be that Venus has transitioned from plate tectonics to a fixed lid, or it could be a completely different way that the interior and surface interact on a planet. We are right on the cusp of figuring that out, and VERITAS should provide the information we need to determine that.”
Herrick also wants to figure out the sequence of events that led to Venus’ terrain.
“Venus is the only solid planet that approaches Earth in terms of the diversity of geologic features on its surface,” he said. “Because erosion is minimal on Venus, you can see pristine examples of a variety of landform types (like volcanoes) that are obscured or modified on Earth by erosion and biological activity.”
Herrick became interested in the space program as a child while his father worked for the New Orleans branch of The Boeing Company, which built a portion of the Saturn V rocket, the vehicle that launched Americans into space in the 1960s and 1970s.
Later, while studying for a master’s degree in geophysics, Herrick called the Lunar and Planetary Institute in Houston, Texas, looking for ideas for a thesis project.
He ended up working with gravity data from the Pioneer Venus mission, 1978-1992, which involved surface mapping the planet with radar, observations of solar winds and measuring sulfuric acid in the clouds.
After earning his PhD, Herrick came to work at the UAF Geophysical Institute in 2004 following a 10-year stint as the staff scientist at the Lunar and Planetary Institute.
VERITAS will provide “such a dramatic improvement in resolution for such a large solid body” that its findings will “definitely be in the upper tier of planetary missions in terms of significance,” Herrick said.
“I have studied data from bodies throughout the solar system, many of which have much higher resolution images than we currently have for Venus, and some of which have higher resolution imaging than the VERITAS mission will produce,” he said. “It is far easier to get high resolution images from a planetary body with no atmosphere or a very thin atmosphere like on Mars.”
VERITAS’ 25-member science team will balloon to 100 people at the height of the mission. Herrick has been with VERITAS from the planning stages.
The German Aerospace Center, the Italian Space Agency and France’s Centre National d’Etudes Spatiales are contributing to VERITAS, which will be based out of NASA’s Jet Propulsion Laboratory in Southern California.
“The research that we do will end up producing a lot of scientific publications and advancing our knowledge of the solar system, including a lot of information relevant to our understanding of Earth,” Herrick said. “Planetary missions, especially ones like VERITAS that will produce tons of spectacular images, also have a lot of interest to the public, and bringing our results to the public will be a major part of the mission.”
He feels lucky to be alive at a time when scientists can gather information directly from planets.
“To be one of only a few thousand people in the history of mankind to be involved in sending something to a dot in the sky is a little overwhelming when I think about it,” Herrick wrote.
Contact staff writer Amanda Bohman at 459-7545. Follow her at twitter.com/FDNMborough.