Two tiny satellites have fallen silent millions of miles away, after proving new technology at Mars.
The twin CubeSats, nicknamed WALL-E and EVE, shadowed NASA's InSight lander to Mars last year. As the lander descended to the Martian surface in November, the briefcase-size satellites flew past the red planet, providing real-time updates to controllers in this first-of-its-kind experiment.
This week, NASA said it hasn't heard from them for more than a month now -- and doubts it ever will.
These were the first CubeSats to venture into deep space, part of an $18.5 million experiment to see whether such compact, cheap devices might serve as radio relays at faraway worlds. Program manager John Baker of NASA's Jet Propulsion Laboratory in Pasadena, California, says "there's big potential in these small packages."
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As for InSight, the robotic Mars geologist has been adjusting the seismometer it placed on the planet's surface in December. It's designed to give researchers a better idea of how Mars and other rocky planets formed.
A dome shield was deployed over the instrument to help it provide accurate data. The shield protects the seismometer from heat and strong winds, which can alter data readings.
"Temperature is one of our biggest bugaboos," said InSight Principal Investigator Bruce Banerdt of NASA's Jet Propulsion Laboratory in Pasadena, which is leading the mission. "Think of the shield as putting a cozy over your food on a table. It keeps SEIS from warming up too much during the day or cooling off too much at night. In general, we want to keep the temperature as steady as possible."
Even on Earth's hospitable environment, seismometers are buried in underground vaults to help protect them from heat.
NBC4's Jonathan Lloyd contributed to this report.