Proba-3 Mission

The Indian Space Research Organisation (ISRO) successfully launched the European Space Agency's "groundbreaking" Proba-3 mission on board its PSLV-59 rocket.

What is Proba-3 mission?

• Proba stands for "Project for On-Board Autonomy", and it refers to a series of experimental missions initiated by the European Space Agency (ESA).
  • Proba-1: Launched in 2001, focused on demonstrating advanced onboard autonomy.
  • Proba-2: Launched in 2009, focused on solar observation.
  • Proba-V: Launched in 2013, an Earth-observing satellite dedicated to vegetation mapping.
• Proba-3 is a joint mission aimed at exploring the Sun’s corona, the outermost layer of its atmosphere, which plays a crucial role in understanding solar dynamics and space weather phenomena.
• The mission aims to study the Sun’s corona at an entirely new scale by creating an artificial eclipse.
• Mission life: Two years
• Launch Vehicle: The PSLV-C59 launch vehicle will carry two ESA satellites, each weighing approximately 550 kg, into a highly elliptical orbit of around 600 x 60,530 km and have an orbital period of 19.7 hours.
• The Proba-3 mission will be unique as it marks the first time two satellites, that will work together to mimic a natural solar eclipse:
  • Occulter Spacecraft (weighing 200 kg)
  • Coronagraph Spacecraft (weighing 340 kg)
• Launched together in a stacked configuration, the two small satellites will demonstrate “precise formation flying. After launch, they will separate and fly in a coordinated manner, creating an artificial solar eclipse in Earth’s orbit.
• The artificial eclipse will provide a 100-fold increase in observation time, enabling scientists to study the corona for longer periods than was previously possible. This mission is expected to generate about 50 eclipses per year, each lasting approximately six hours.
• Study of the Sun’s Corona: Studying the corona is crucial because it is the source of space weather—solar winds, solar storms, and other phenomena that affect both the Earth’s atmosphere and satellite operations. Understanding the corona is key to predicting and mitigating space weather events.

Increasing reliability of ISRO’s PSLV

• ISRO's PSLV has built a reputation for reliability, with only two failures in 60 launches.
• This track record, coupled with India's active space diplomacy and evolving space policy, makes PSLV a favored choice.
• The European Space Agency (ESA) has been increasingly reliant on ISRO for launching missions, such as Proba-3, due to the unavailability of its own operational launch vehicle.

Historically, ESA's Ariane rockets were known for their reliability, and India frequently used Ariane to launch its satellites. However, with Ariane 5 retired and Ariane 6 still under development, ESA lacks an active launch vehicle, leading them to seek alternative providers like ISRO.