The NASA New Horizons probe reached Pluto in 2015, but it approached the dwarf planet in minutes because of its tremendous speed. The agency is now considering sending another mission to Pluto, but it will remain in orbit to investigate the surface. A study commissioned by NASA from the Southwestern Research Institute (SwRI) determined what would be needed to establish a long-term presence in the area around Pluto.
New horizons began in 2006, when Pluto was still officially considered a planet. He set the record for the fastest launch of spacecraft ever, because he had a long, long journey ahead. After nine years, he flew past Pluto, sending back the first close images and data from the former Ninth Planet. To stay in Pluto's orbit, New Horizons would need significant reserves of fuel to vent its speed. Instead, NASA redeployed New Horizons to explore other objects on the Kuiper Belt. The probe reached an object called Ultima Thule (2014 MU69) earlier this year.
SwRI is the appropriate outfit that offers follow-up to New Horizons – he leads the New Horizons mission for NASA. NASA's new funding will allow SWRI to submit a complete mission plan and cost estimate for a future mission. NASA will use the study to inform its next Planetary Science Decade in 2020. NASA will then decide where to focus its planetary science efforts over the next 10 years.
We can make some assumptions about what mission SwRI will recommend, thanks to a previous concept of Pluto orbit that has evolved over the last few years. The SwRI orbiter proposed several years ago will use ion engines such as the Zora spacecraft and a source of nuclear energy that can support it in the external solar system. It relies on Pluto's moon's charon, as gravity helps to change its orbit, much like Cassini's orbiting Saturn and its moons. A past concept required a farmer to set up a Charon store to then observe Pluto from one angle for an extended period of time. It is not known whether SWRI will recommend any surface tools in its new study.
The short flight of Pluto's New Horizons revealed an unexpectedly complex small world of clouds, vast plains of frozen nitrogen, and more. Not surprisingly, NASA is thinking of going back.