It has been 30 years since NASA’s last visit to Venus in Magellan’s orbit in 1990. Two new missions have now been selected to study the deadly atmosphere, crushing pressure and volcanic landscape.
The process dates back to February 2020, when NASA announced that four missions must go through a nine-month peer review process. They were all part of the Discovery program, launched by NASA in 1992 to bring together scientists and engineers to create exciting, groundbreaking missions. Apart from the leading missions – such as curiosity and perseverance ̵
Venus’ two winning missions, Davinci and Veritas, received $ 500 million (£ 354 million) and will be launched for some time between 2028 and 2030. But competition was tough from the two losing missions that would go to Io and Triton. , satellites of Jupiter and Neptune, respectively. So what do we miss as a result?
Explore Jupiter’s strange moon
Yo is a strange moon – even among moons that are strange to begin with. As Jupiter’s innermost moon, orbiting only 350,000 km above the cloud, it gives Io an extreme heating mechanism that makes it the most volcanically active object in the solar system, sporting over four hundred volcanoes.
You might think, given that we live on a planet with a large proportion of volcanoes, that we would have a good idea of where all this heat is coming from. In fact, according to Alfred McEwan, principal investigator on the proposed Io Volcanic Explorer or IVO mission, we are still deeply unaware of how this actually works.
Read more: Nasa has announced two missions to Venus by 2030 – that’s why it’s exciting
IVO is designed to perform multiple moon flights and use a set of tools to map activity on and below the surface. By gathering information about Io’s magnetic and gravitational fields, filming huge lava eruptions, and analyzing gas and dust coming out of the moon, IVO will help scientists learn how Io’s heat is generated and lost.
All this information is crucial – not just for great videos of space volcanoes – because this type of extreme activity is considered an important aspect of the formation and evolution of planets. By understanding the processes that drive change in Io, we can eventually learn more about how the planets and moons came into being.
The ice giants
The least studied and understood planets are Uranus and Neptune and they contain some of the strangest things in the solar system. Uranus has an axial inclination – the angle of its axis of rotation relative to the plane orbiting the Sun – so extreme that it rotates laterally. This is thought to be the result of a giant collision in the past of the solar system.
Neptune, meanwhile, is home to the only large moon orbiting its parent planet, the curious Triton. The particular orbital position is not where the oddities end. The plane in which Triton orbits is compensated by an extreme 23 degrees compared to that of Neptune and is believed to have moved to Neptune from the Kuiper Belt, a region beyond Neptune’s orbit filled with icy remnants of the solar system.
Triton also has an active ionosphere – a layer of charged particles in its atmosphere ten times more active than any other moon that is not powered by the sun – as well as a constantly changing and dynamic surface covered with nitrogen snow. When Voyager 2 photographed the moon, he discovered cryovolcanoes – geysers that erupt ice and gas up to 8 km high, which could mean an underground ocean.
Trident’s proposed mission would be to explore these very strange things about the moon. He proposed a three-pronged approach using instruments to measure Triton’s magnetic field. It would identify the presence and structure of the subterranean ocean. High-resolution infrared cameras would allow the spacecraft to image the entire surface using sunlight reflected from Neptune, showing scientists what has changed since the last visit in 1989. Finally, the spacecraft would try to find out how Triton’s surface remains so dynamic and young.
Eventually, Trident and IVO lost the missions of Venus. It would be fascinating to explore the outer parts of the solar system again or to see the colossal volcanoes of Io. But Venus is a charming planet, with its mysteries and potential.