Written by By Alycia Holt, CNN
Astronauts on the International Space Station have had to delay an important repair job due to space junk.
Three astronauts were set to enter the space station in an emergency spacewalk with a replacement antenna Saturday, but the four-hour spacewalk was bumped to Monday due to a large debris cloud in space.
Crew member Shane Kimbrough, currently living on the ISS, expected to launch around 5 p.m. ET with some replacement parts for a broken optical system called the Vision Control Transmitter (VCT). The antenna typically supports astronaut sight and provides navigation and control of vital systems, including the power and internet connections needed to run the station.
Space junk was discovered at NASA’s Goddard Space Flight Center Monday, which resulted in the delay. The debris consists of large pieces of junk up to 5.9 miles long and larger. It is predicted to cross Earth’s orbit on Dec. 19, according to NASA.
The astronauts had been scheduled to replace the VCT on Sunday, but engineers said the mission should be delayed as to not alter the orbit of debris. The new plan is to tackle the antenna Monday and then wait for the debris to pass again on Tuesday morning.
The VCT is part of an emergency backup system in case the primary system on the station fails. This satellite provides communication and navigation services to critical systems on the station such as space elevators, solar arrays and solar cells.
The ISS is constantly watched by NASA’s Space Surveillance Network, which continuously tracks space debris, including a mass of six-meters wide believed to be a US military satellite. According to the network, it has been tracked for the past 20 years and could cause more than $400 billion in damage to the space station and the ground.
The agency is aware of when pieces of debris will pass past the ISS and has four trackers around the ISS itself as well as onboard measuring and imaging equipment.
There is another delay for the recovery mission of an unmanned SpaceX Dragon cargo craft that crashed into the ocean Tuesday.