Despite its fiery surface, Venus is the most similar planet to Earth in the entire solar system. However, missions to our sister world are few and far between. India hopes to change that. (Credit: NASA/JPL-Caltech) Much to the delight of planetary scientists from around the world, the Indian Space Research Organisation (ISRO) plans to send its first-ever Venus orbiter to our sister planet in just a few short years. And what’s even more exciting is the space agency recently invited other countries to join in on the fun. On November 6, the ISRO published an Announcement of Opportunity regarding their planned mission to Venus, which is tentatively scheduled for launch in mid-2023. In the announcement, the space agency encouraged international scientists to submit proposals for experiments and instruments that could potentially tag along to Venus aboard the Indian orbiter.
Ignoring Our Nearest Neighbor
Despite being the closest planet to Earth, it’s been nearly 30 years since NASA has specifically targeted Venus with a spacecraft. And since then, only a handful of other international missions have ventured to the hellish planet. This is somewhat surprising, especially when you consider that, at about 4.5 billion years old, Venus is roughly the same age, mass, and size as Earth. However, unlike Earth, which maintains an inviting and life-nourishing environment (at least currently), Venus is an extremely hostile and unforgiving world. For starters, Venus is plagued by a runaway greenhouse effect, which, over time, has generated a dense, carbon dioxide-rich atmosphere that is extremely adept at trapping heat. In fact, Venus’ thick shell of carbon dioxide is such an effective blanket that the average temperature of the planet’s surface is over 850 degrees Fahrenheit (455 degrees Celsius).
Though Venus is roughly the same size as Earth, its surface is truly otherworldly. Not only is Venus covered in countless volcanoes and lava plains, its surface is also almost ten times hotter than Earth’s. (Credit: NASA/JPL-Caltech)
But although the dense clouds and searing heat of Venus are part of the reason why the planet is so difficult to study, another part of the problem could aptly be described as a “runaway scientist effect.” “In the absence of new Venus missions and data, it is increasingly difficult to generate support for students and early-career researchers interested in Venus,” said Patrick McGovern of the Lunar and Planetary Institute in a statement. This lack of momentum, he said, “in turn affects the ability to rally support for new missions.” And without a steady stream of future venusian explorers coming down the pipeline, our nearest neighbor may eventually be forgotten as we continue to push ever-outward into the solar system.
The first Indian orbiter mission to Venus will launch atop the Geosynchronous Satellite Launch Vehicle Mark III, which is seen here on a launch pad at Satish Dhawan Space Centre in Sriharikota. (Credit: ISRO)
An Adventure to Venus Though widespread interest in Venus has somewhat waned over recent decades, India’s upcoming mission aims to turn that tide. As part of a still unnamed mission, ISRO will launch an approximately 5,500-pound (2,500-kilogram) spacecraft aboard the heaviest rocket they currently operate: the Geosynchronous Satellite Launch Vehicle Mark III. The sheer size and power of this three-stage rocket will enable the spacecraft to ferry a full suite of instruments, weighing up to about 220 pounds (100 kg), all the way to our sister planet. The spacecraft will initially be placed in a very inclined orbit around Venus — one that will take it as close to the planet as 310 miles (500 kilometers) and as far away as 37,300 miles (60,000 kilometers). Once in place, according to the ISRO’s announcement, scientists will then likely make slight adjustments to the spacecraft’s trajectory to help gradually shrink its orbit for a better view. After the orbiter’s flight path is finalized, the mission will begin full-on science operations. One of the main goals of the mission is to closely analyze Venus’ surface features to better understand how the planet resurfaced itself so dramatically over the past billion years. Additionally, the mission will investigate what role solar wind and solar radiation play in heating the planet, as well as study the chemistry and dynamics of the venusian atmosphere. Although ISRO has already selected 12 Indian instruments that will venture to Venus aboard the spacecraft — including atmospheric analyzers and a whole host of cameras — according to rocket scientist and ISRO Chair Kailasavadivoo Sivan, “Planetary exploration should be all about global partnerships.” And that’s why ISRO made a call for more instrument proposals: Collaboration makes the science grow stronger.
Viva la Venus
Despite the recent lull in Venus exploration and the resulting disruption in the Venus-expert pipeline, India's upcoming mission may serve as an inflection point, where new findings spur revived interest in our sister world. “In my view,” said McGovern, “we are presently at the reconnaissance stage of [Venus] exploration, equivalent to that of pre-1997 Mars." And considering the plethora of highly successful missions that have explored Mars in the past two decades — including NASA’s Spirit, Opportunity, and Curiosity rovers, as well as the ISRO’s Mars Orbiter Mission — the next 20 years could very well be a much-needed score for Venus.