Nasa's Europa Clipper mission is edging closer to being launched following a request for $30m (£19.9m) for preliminary studies into the operation.

David Radzanowski, Nasa's chief financial officer, said the space agency is requesting funds to study Europa following the announcement of its White House budget request for 2016.

The $30m is in addition to the $100m Congress added to Nasa's budget to start work on the mission to Jupiter's moon last year.

Previously, all of their proposed mission concepts have had failings – either being too small or too big, for example – but the Europa Clipper mission is "just right", JPL scientist Robert Pappalardo, told Discovery News.

The Europa Clipper mission would conduct detailed reconnaissance of Jupiter's moon Europa. It would investigate whether or not the moon could harbour suitable conditions for life: "The mission would perform a detailed investigation of Europa using a highly capable, radiation-tolerant spacecraft that would perform repeated close flybys of the icy moon from a long, looping orbit around Jupiter."

Costs would include science instruments to penetrate the frozen crust, to work out the thickness of the ice shell, an infrared spectrometer to look at the composition of the moon's surface materials and cameras to look at its features.

The Clipper would perform 45 flybys of Europa at varying altitudes, the closest being about 25km above the surface.

Europa is believed to be the best candidate in the search for extra-terrestrial life, as it is thought to conceal an ocean more than twice the volume of the Earth's seas.

Under its frozen crust, scientists think the moon could harbour the key ingredients for a habitable environment, thus life.

"Europa's ocean, to the best of our knowledge, isn't that harsh of an environment," said astrobiologist Kevin Hand, JPL's deputy chief scientist for solar system exploration. However, he added that the Europa Clipper mission is not primarily to find alien life.

"The way we framed the Europa mission science objectives is not to specifically look for life, but to understand habitability; the ingredients for life."

If everything goes to plan, the spacecraft could be launched in the 2020s. It could also reach the moon in under three years if a powerful rocket currently being developed is used for the mission.