Shukrayaan 

• Shukrayaan is ISRO’s venus mission, the idea of which was born in 2012.
• Shukrayaan I will be an orbiter mission. 
• Its scientific payloads currently include a high-resolution synthetic aperture radar and a ground-penetrating radar.
• The mission is expected to study Venus’s geological and volcanic activity, emissions on the ground, wind speed, cloud cover, and other planetary characteristics from an elliptical orbit.
• The launch will involve GSLV Mark II or GSLV Mark III

Launch windows of Venus

• Optimal launch windows from Earth to Venus occur once around every 19 months. 
• This is why ISRO has ‘backup’ launch dates in 2026 and 2028 should it miss the 2024 opportunity. 
• But even more optimal windows, which further reduce the amount of fuel required at liftoff, come around every eight years.

Other Venus mission

• Veritas, Mariner Series, Pioneer Venus-I, Pioneer Venus- II- Of USA
• EnVision, Venus Express- Europe
• Venera Series, Vegas 1, Vegas 2
• Akatsuki- Of Japan- Of Russia

Why in news

• Indian Space Research Organisation (ISRO) said that the mission could be postponed to 2031.

https://www.thehindu.com/sci-tech/science/isro-pushing-venus-mission-shukrayaan-to-2031/article66382110.ece