20 DISCOVERMAGAZINE.COM
CASSINI
IS DEAD;
LONG LIVE
CASSINI
NASA/JPL-CALTECH//SSI/KEVIN M. GILL/CC BY-SA 2.0; CASSINI: NASA❯
IN OCTOBER 1997, a Titan rocket
streaked across the sky and shot
a spacecraft called Cassini toward
Saturn. The road trip, minus roads, was
long, and Cassini didn’t arrive until 2004.
But it stayed there till its mission ended
on Sept. 15, 2017 — with a bang, and a
good deal of whimpering from Earth.
Early that morning, engineers at
NASA’s Jet Propulsion Laboratory sent
Cassini down to meet the planet it had
spent 13 years studying. The greeting
was fatal for Cassini, which disintegrated
as it charged through Saturn’s
atmosphere. It was a planned death,
a self-sacrifice that meant it wouldn’t
crash into Saturn’s moons.
Scientists didn’t want to contaminate
those satellites — Titan and Enceladus
— precisely because of what Cassini
had revealed: They weren’t barren balls,
but ones with oceans, water, internal
energy and nutritious chemicals. The
moons demonstrated that planets aren’t
the only habitable spots in this solar
system, and beyond.
Cassini’s gaze at Saturn also revealed
more about the formation of giant
planets and regular solar systems.
“By studying those rings up close and
personal, you could draw analogies
to how solar systems might form
and evolve,” says Scott G. Edgington,
Cassini’s deputy project scientist.
“There will be generations of scientists
who get their Ph.D.s and do research
with Cassini data,” he says. “Who
knows what they'll find in those 0s and
1s?” That’s why, despite the emotional
eulogies, Cassini’s intellectual life will
continue long after its physical death.
SARAH SCOLES