In 2012, NASA initiated a new series of studies to yet again define a Europa mission.

The leading contender that emerged from this process was a spacecraft capable of making multiple flybys of the Jovian moon,
-- and this became known as the #Europa #Clipper.

Scientists realized it was impractical to build an orbiter
-- because the spacecraft would have a short lifetime due to constant exposure to the intense radiation emanating from Jupiter.

By making dozens of flybys, Clipper could swoop into the inner Jovian system, gather data from Europa, and then transmit it back to Earth when the spacecraft was further from Jupiter's harsh radiation environment.

Starting in fiscal year 2013, Culberson began adding money to NASA's budget specifically for the development of a Clipper mission,
even though NASA had not committed to starting a program.

"We're only going to have one chance at this in our lifetimes," he told me that year,
explaining his effort to essentially force NASA to green-light a Europa mission after nearly two decades of dithering.

"We've got one shot. I want to make sure you and I are here to see those first tube worms and lobsters on Europa."

NASA could not afford to ignore Culberson, who was no longer a junior Congressman.

In December 2013, U.S. Rep. Frank Wolf, a Virginia Republican, said he would not run for re-election in 2014,
leaving Culberson as the odds-on favorite to replace him as chairman of an appropriations subcommittee that oversees NASA.

Effectively, this gave Culberson control over the agency's purse strings.

In January 2015, that happened.

Now chairman of the all-important budget subcommittee,
Culberson began making periodic trips to the Jet Propulsion Laboratory in California.

To the mortification of NASA's senior leaders and communications officials,
Culberson decided to invite me to come along for sessions that would last a day or two.

There were no restrictions.

I got to sit in on all the meetings, hear the discussions, and even participate at times.

Even better, at Culberson's insistence, it was all on the record.

Let me explain how rare an opportunity this is.

Typically, journalists learn about space exploration by interviewing sources, attending press conferences, and reading scientific papers.

But to be in the room where it happened?
-- That just does not happen.

But Culberson was inviting me behind the curtain into detailed discussions where the mission planners and leadership at the NASA facility in California explained what they were doing,
why they were doing it,
-- and where they needed political help.

It was eye-opening for me to see how these kinds of missions got done and see power in action.

It all began decades ago

After the two Voyager flybys in 1979, NASA sent a dedicated probe named #Galileo to Jupiter in the 1990s.

This spacecraft made several passes by #Europa during its nearly eight years in orbit around Jupiter, and data from this mission indicated the likely presence of a water ocean beneath the moon's icy surface.

In the nearly three decades since then, planetary scientists have had little more to go on than these tantalizing clues.

They've desperately wanted to know more.

Almost immediately after the first Europa data from Galileo beamed back to Earth in 1996, the administrator of NASA at the time,
#Dan #Goldin,
asked scientists at the agency's Jet Propulsion Laboratory in California whether a small mission dedicated to the study of Europa was possible.

Fitting within Goldin's ethos of
"faster, better, and cheaper,"
he wanted a design for a spacecraft carrying just 27 kg of scientific instruments to Europa,
about the same mass as a suitcase than can be checked on to an airplane.

"That was the beginning of a Europa orbiter concept," said science writer David Brown, author of
"The Mission", which tells the definitive story of the Europa Clipper mission.

The original science objectives outlined during the development of this orbiter mission
—to investigate the composition of Europa’s ice shell and ocean, the world's geology, and to search for and characterize any plumes emanating from the ocean below
—remain more or less the same with #Clipper.

However, as often happens with deep space missions, the budget doubled.

NASA's chief of science at the turn of the century, astrophysicist Ed Weiler, killed the nascent Europa program.

But scientists were still interested.

In 2003, the National Research Council published its first "decadal survey,"
a process by which the scientific community outlines research priorities for NASA.

Over the years, these decadal surveys have become influential tools for guiding NASA policy.

In this first survey, scientists recommended that NASA establish a "large-class" mission to study #Europa