Mars will disappear from Earth’s sky for two weeks starting Saturday.
That’s thanks to a scientific phenomenon known as solar conjunction: a period during which the sun obscures Mars and Earth from each other.
“Like dancers on either side of a huge bonfire,” NASA said, “the two planets are temporarily invisible to each other.”
Earth and Mars experience solar conjunction every two years, NASA said. Space.com reported that the two planets were an average of 140 million miles apart — but during solar conjunction, they’ll be separated by about 235 million miles.
Solar conjunction also affects NASA’s ability to communicate with and send signals to spacecraft on Mars.
“It’s impossible to predict what information might be lost due to interference from charged particles from the Sun, and that lost information could potentially endanger the spacecraft,” NASA said. “Instead, prior to solar conjunction, engineers send two weeks’ worth of instructions and wait.”
The 2023 moratorium on commanding Mars spacecraft is from November 11 to November 25, NASA added.
But scientists have emphasized that this doesn’t mean missions to Mars will get any time off.
“Our mission teams have spent months preparing to-do lists for all our Mars spacecraft,” Roy Gladden, the manager of the Mars Relay Network, said in a NASA statement.
“We’ll still be able to hear from them and check their states of health over the next few weeks.”
This article was originally published by Business Insider.
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