Tchances are very slim that you’ll ever step inside the room known as High Bay 1 at NASA and Caltech’s Jet Propulsion Laboratory in Pasadena, California. If you happened to be inside, you certainly couldn’t just walk in while they were. First, you’ll enter an anteroom where automated brushes will be applied to your shoes to remove any dirt or particles; you’ll then stand under an air shower that will blow lint, dirt and any other stray debris off your clothes. You’ll then move to a dressing room where you’ll stand on a sticky mat to make sure the bottoms of your shoes are clean too, and finally you’ll put on what’s called a bunny suit – a robe, head covering, and, no matter how clean your shoes are so far, canvas boots.
Only then will you be admitted to High Bay 1, a 14 m (45 ft) high, 21 m (68 ft) wide volume of space that qualifies as a Class 10,000 clean room – meaning it has fewer than 10,000 particles 0.5 microns or greater per cubic foot of air. (A micron is about 100 times smaller than the width of a human hair.) But it would be worth the scramble to get into the loft, especially this week—since, as reported by NASAThe main body of the new spacecraft, known as the Europa Clipper, has just been put into place for assembly and testing in preparation for its 2024 launch.
Weighing 6,000 kg (13,000 lbs) and measuring 3 m (10 ft) tall and 1.5 m (5 ft) wide, the Europa Clipper will be launched aboard a Falcon Heavy rocket at six years, 2.8 billion km (1.8 billion miles) orbiting trajectory to reach what may be the most promising place in our solar system for extraterrestrial life: Jupiter’s bright white moon Europa. Measuring 90% of the diameter of our moon, Europa is covered by a 15 to 25 km (10 to 15 mi) thick shell of water ice covering a warm, globe-encircling ocean up to 150 km (100 mi) deep. This single Europan ocean contains twice as much water as all of Earth’s oceans combined – and the Europa Clipper was designed to learn more about it.
The spacecraft will not land on Europa, but is designed to make at least 50 close flybys of the moon, using a suite of instruments to take its chemical and geological measurements. Among the onboard hardware are a plasma sensor performing surface and subsurface magnetic drilling; high definition wide angle camera; a heat radiating system; and an ultraviolet spectrograph. All this equipment and more will be painstakingly installed in the spacecraft over the next two years, and the scene in High Bay 1 today is highly focused, highly charged. A heavy vault is currently attached to the spacecraft to protect the delicate instruments from the intense radiation field that surrounds Jupiter; propulsion tanks are attached that will fuel 24 onboard thrusters; and almost 640 m (2,100 ft) of bright copper cable – enough to wrap twice around a football field – is coiled into the ship’s hull.
The job won’t come cheap: The Europa Clipper mission will set NASA back at least $4.25 billion in design, construction and operations costs. But the space community — especially biologists who specialize in studying the possibility of extraterrestrial life — believe it will be worth more. The rule of life—at least life as we know it—has always been to follow the water. This is what gave rise to life on Earth – and it is what may have given rise to life in Europa as well. Answers — or at least clues — to this age-old question may be coming soon, and it was at High Bay 1 that the work to find them began in earnest this week.
This story originally appeared in TIME Space, our weekly newsletter covering all things space. You can register here.
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