CubeSats set for new role as planetary explorers
Sen—A team at NASA's Goddard Space Flight Center is developing technology that could enable tiny cube shaped satellites, known as CubeSats, to explore planets and moons in deep space.
CubeSats, which measure 10 cm (four inches) cubed, are growing in popularity as a low-cost means of space exploration. More than 75 of the small satellites were launched in 2014. All CubeSats are currently deployed in Earth's orbit either as part of a larger mission's payload or after being released by the NanoRacks launcher fitted to the International Space Station. The small satellites can be joined together to form clusters two or three units wide, and common componets can be bought from online shops such as Clyde Space, making them relatively low cost to assemble.
To date, CubeSats have been confined to Earth's orbit. Dr Jaime Esper, a technologist at NASA's Goddard Space Flight Center, hopes to change that.
Dr Esper is the Principal Investigator and vehicle designer for a concept called CubeSat Application for Planetary Entry Missions (CAPE) that could see CubeSats diving to the surfaces of other planets and moons, gathering science data on the way.
To reach another planet, the CubeSat would share a ride aboard a larger spacecraft for the long journey. Once in the neighborhood of its destination, the CubeSat would be released to begin its own mission.
Each CubeSat would have a service module fitted with propulsion and attitude-control. Upon arriving at its celestial target, a separate entry probe armed with various sensors, gyros and radiometers would be released to plunge through the planet's atmosphere. Data, such as atmospheric pressure and temperature, collected during the probe's descent to the surface, would be transmitted back to the service module, which would relay the information home to Earth.
"CAPE entry probes can provide essential insight into the bulk properties of planetary atmospheres by measuring their density, temperature, and composition," Dr Esper told Sen.
"Sent in numbers, they render the potential to observe multiple in-situ locations in a planet or satellite’s atmosphere. I am excited about this possibility, as it opens up an entirely new capability and manner of exploration for NASA, with high potential for university and student participation."
A prototype of the entry module, which has been called the Micro-Reentry Capsule (MIRCA), will undergo a test this summer when it is released at an altitude of about 30 km (19 miles) from a balloon over New Mexico. The objective is to test the tiny probe's stability during entry. The prototype is being built at NASA's Wallops Flight Facility. A further test Dr Esper would like to see would be to release the entry probe from the International Space Station.
If the concept is proven it could provide a low cost way of collecting data from bodies around the Solar System.
A prototype of the Micro-Reentry Capsule (MIRCA) due to be tested in the summer of 2015. Image credit: NASA/Goddard
NASA is keen to see the development of CubeSat technology. Earlier this year the space agency announced a $5 million prize fund for teams that can prove CubeSats work in deep space. The aim of the competition, called the Cube Quest Challenge, is to learn if the small satellites can operate beyond Earth. Cash prizes are on offer for teams that can put a CubeSat into a stable orbit around the Moon and demonstrate its ability to communicate back to Earth. A prize of $1.5 million is on offer for teams that can put a CubeSat at least four million km (2.5 million miles) from Earth and demonstrate its ability to communicate.
Though CAPE is developing technology that could meet the criteria of the Cube Quest Challenge, the team won't be able to enter the challenge—they are precluded from taking part by reason of their employment with NASA.
Meanwhile, ten more CubeSats were launched on May 15 from Cape Canaveral Air Force Station, Florida, aboard a United Launch Alliance Atlas 5 rocket. They included a prototype for a CubeSat designed to use a solar sail to propel itself through space—the crowd-funded mission, known as LightSail, has been developed by The Planetary Society.