Starting Saturday, Mars will disappear from the sky for two weeks. This is thanks to a scientific phenomenon known as solar conjunction: the period when the Sun blocks Mars and Earth from each other.

“Like dancers on either side of a large bonfire,” NASA said, “two planets are temporarily invisible to each other.”

Earth and Mars experience a solar conjunction every two years, NASA said. The two planets are reported to be an average of 140 million miles apart, but will be separated by approximately 235 million miles during solar conjunction.

The Sun conjunction also affects NASA’s ability to communicate with and send signals to spacecraft on Mars.

“It is impossible to predict what information may be lost due to interference from charged particles from the Sun, and this lost information could potentially endanger the spacecraft,” NASA said. “Instead, engineers send out instructions and wait two weeks before solar connection.”

NASA added that the moratorium on commandeering a spacecraft on Mars in 2023 will be in effect from November 11 to 25. However, scientists emphasized that this does not mean that missions to Mars will be on holiday.

“Our mission teams have spent months preparing to-do lists for all of our Mars spacecraft,” Roy Gladden, director of the Mars Transport Network, said in a statement to NASA. “We will still be able to hear from them and check on their health in the next few weeks.”