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Isro began a revised countdown on Thursday for the launch of the European Space Agency’s Proba-3 mission, following a delay caused by “an anomaly detected” in the satellite propulsion system.
The Bengaluru-based space agency rescheduled the launch of the European Space Agency’s (ESA) Proba-3 mission to December 5 at 4.04 pm, after a request from ESA. It was initially scheduled for Wednesday at 4.08 pm from their spaceport.
Sharing a post on X, Isro said, “PSLV-C59/PROBA-3 Mission. Countdown commenced. Lift-off time 16.04 pm IST, 5th December 2024. Stay tuned as PSLV-C59 prepares to deploy ESA’s Proba-3 satellites into orbit.”
“Probas,” a Latin word, translates to “Let’s try.”
- The Proba-3 (Project for Onboard Anatomy) has two satellites: Coronagraph (310kgs) and Occulter (240kgs).
- These spacecraft are designed to operate in precise formation, maintaining accuracy to a millimetre, to examine the Corona, the Sun’s outer atmosphere.
- According to ESA, the Sun’s corona is much more hotter than its surface and serves as the origin of space weather, making it a subject of substantial scientific and practical interest
- The primary goal is to showcase precise formation flying capabilities, with both spacecraft units being deployed simultaneously in a stacked arrangement once they reach the intended orbital position.
- The PSLV-C59 rocket, standing 44.5 meters tall, marks its 61st flight and the 26th mission utilizing the
PSLV-XL variant , designed for deploying heavier satellites. - Following lift-off at 4:04 PM, the two satellites, Coronagraph and Occulter, will go on an 18-minute journey to achieve their designated orbit.
- Once in position, the two spacecraft will operate 150 meters apart, functioning as a unified satellite system.
- This configuration allows the Occulter to block the Sun’s solar disk, enabling the Coronagraph to observe and study the Sun’s corona, or outer atmosphere, for scientific research.
The ESA contract has been secured by NewSpace India Ltd, Isro’s commercial division.
For Isro, besides providing its trusted workhorse PSLV vehicle for the launch, this mission would provide key insights on taking up scientific experiments on the Sun after its maiden mission–Aditya-L1 which was successfully launched in September 2023.
The mission, supported through the General Support Technology Programme, involves satellites that will approach the solar rim for up to six hours per session, with each spacecraft following approximately 19-hour Earth orbits.
The mission had been anticipated as a landmark collaboration, marking ESA’s return to launch with Isro after 23 years. The launch was particularly challenging, demanding that the PSLV carry the spacecraft into a highly elliptical orbit with an unusual apogee and perigee.
