Invites study ideas for new mission

It’s official. The Indian Space Research Organisation (ISRO) has invited scientists to suggest studies for a potential orbiter mission to Venus - somewhat similar to the one that landed in Mars in 2013.

ISRO plans to send a spacecraft that will initially go around Venus in an elliptical orbit (500 km x 60,000 km) before getting closer to the ‘Yellow Planet’. The spacecraft will carry a set of instruments weighing 175 kg and using 500W of power. The scientific community has been given a month’s time to suggest space-based studies by May 19.

"The Announcement of Opportunity [AO] is just the beginning. The studies must be finalised, a project report would have to be presented and approved. A formal mission may not happen before 2020," a senior ISRO official told The Hindu.

A mission must be approved by ISRO's Advisory Committee on Space Sciences, then the Space Commission and later by the government.

Venus, the second planet from the Sun, comes closest to Earth roughly every 583 days, or about 19 months.

Venus, our closest planetary neighbour, is similar to Earth in many aspects. However, it takes only 225 days to revolve around the Sun. Secondly, the surface is very hot due to nearness to the Sun.

India's previous and second planetary outing, the record-setting ₹450-crore Mars Orbiter Mission (MOM) of 2013, continues to impress. The orbiter is going round the Red Planet even as you read this — well beyond its planned life of six months.

An orbiter sent to the Moon in 2008 was delivering data until about three months before its estimated life span came to an end. A second Moon landing mission is planned in early 2018.

MOM was sent on the light-lift PSLV launch vehicle. The more powerful GSLV rocket has started transporting regular communication satellites and may be an option for the Venus mission.

Why Venus?

The AO says the planet, described as Earth's twin sister, is similar to our planet in size, mass, density, gravity and is also believed to be around 4.5 billion years old. Yet, "There still exist gaps in our basic understanding about surface features and processes, and the super rotation of the Venusian atmosphere," etc.

Ever since the then USSR sent the Venera mission to Venus in February 1961, there have been close to 30 missions to the planet, the last one being Japan’s Akatsuki in 2010. These comprised orbiters, landers, atmospheric probes and fly-bys.

The erstwhile Soviet Union tops the list with 16 Veneras and two Vegas. The US had Mariner, Pioneer and Magellan missions. New missions are in the pipeline.