Guest : Dr Pieter Kotze | Head at Geomagnetism Group At Hermanus

The launch of NASA’s next Mars rover mission has been delayed to no earlier than July 30 because of a launch vehicle processing issue, the latest in a series of slips that have now used up nearly half of the available launch opportunities for the mission.
 
NASA announced June 30 that the mission, previously scheduled to launch July 22, would be delayed to investigate “off-nominal” data from a liquid oxygen sensor line during a wet dress rehearsal of the mission’s Atlas 5 launch vehicle June 22 at Cape Canaveral, Florida - according to SpaceNews.com. 

The mission was originally scheduled to launch July 17, the beginning of its launch period, but has slipped three times. None of the slips have had to do with issues with the Mars 2020 spacecraft itself - NASA announced. 

The Mars 2020 project (carrying a rover named Perseverance) will land on Mars on Feb. 18, 2021, regardless of what day it launches during the current launch period. The rover will land in Jezero Crater on Mars for mission designed to last at least one Martian year, or 687 Earth days. Perseverance’s instruments will reportedly look for signs of past life on Mars, but the mission’s biggest purpose is to cache samples of Martian rock for later return to Earth.