In Dante Alighieri’s epic poem The Divine Comedy, the famous words “Abandon all hope, ye who enter here” adorn the gates of hell. Interestingly enough, Dante’s vision of hell is an apt description of what conditions are like on Venus. With an average temperature of 450 °C (842 °F), atmospheric pressures 92 times that of Earth, and clouds of sulfuric acid rain to boot, Venus is the most hostile environment in the Solar System. It is little wonder why space agencies, going all the way back to the beginning of the Space Age, have had such a hard time exploring Venus’ atmosphere.
Despite that, there are many proposals for missions that could survive Venus’ hellish environment long enough to accomplish a sample return mission. One such proposal, the Sample Return from the Surface of Venus, comes from aerospace engineer and author Geoffrey Landis and his colleagues at the NASA Glenn Research Center. Their proposed concept was selected for this year’s NASA Innovative Advanced Concepts (NIAC) program. It consists of a solar-powered aircraft that would fashion propellant directly from Venus’ atmosphere and deploy a sample-return rover to the surface.
On September 8th, 2016, NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) mission launched from Earth. Its primary mission was to rendezvous with the asteroid Bennu, a carbonaceous Near-Earth Asteroid (NEA), obtain samples from its surface, and return them to Earth for analysis. On December 3rd, 2018, the mission reached Bennu and spent the next two years searching for the optimal place to retrieve these samples. Tomorrow, on Sunday, September 24th, the mission will finally deliver these samples to Earth for analysis.
Last week, on Saturday, September 16th, the OSIRIS-REx mission was spotted by the ESA’s Optical Ground Station (OGS) 1-meter telescope on the island of Tenerife, Spain. The spacecraft was still 4.66 km million (2.9 million mi) from Earth, but well on its way to returning. This will be the last time OSIRIS-REx will be spotted by ground-based telescopes before it reaches Earth to deliver its sample and heads back out into space.
When it landed on Mars in February of 2021, the Perseverance rover joined a small armada of robotic explorers working hard to characterize Mars’ environment and atmosphere and determine if it ever supported life. But unlike its predecessors, one of the key objectives of the rover is to obtain samples of Martian soil and rock, which it will leave in a cache for later retrieval by a joint NASA-ESA mission.
This will be the first sample return from Mars, and the analysis of these samples will provide new insight into the geological and environmental evolution of Mars. The first attempt to obtain a sample didn’t go so well, with the sample crumbling before it was placed in the cache. Undeterred, the science team moved onto the next site and prepared to try again. A few days ago, NASA confirmed that the rover succeeded in its second attempt and has the pictures to prove it!
Currently, NASA’s plan for exploring Titan (Saturn’s largest moon) is to send a nuclear-powered quadcopter to explore the atmosphere and surface (named Dragonfly). However, another possibility that was presented this year as part of the NASA Innovative Advanced Concepts (NIAC) program is to send a sample-return vehicle with Dragonfly that could fuel up using liquid methane harvested from Titan’s surface.