About a week after NASA's Juno spacecraft entered orbit around Jupiter
on July 4, the first images taken from the spacecraft's perch around
the largest planet in the solar system have made their way back to
Earth.
On Sunday, six days after starting its orbit, Juno's
visible light camera was turned on and the JunoCam captured the above
scene, proving it survived its first pass through the planet's intense
radiation.
The view shows Jupiter with its famous giant red spot on display, as
well as three of its four major moons: Io, Europa and Ganymede. While Io
is a turbulent world marked by violent volcanic activity, Europa and
Ganymede are believed to harbor hidden ocean, with Europa a leading
target for the search for life beyond Earth.
NASA says
high-resolution views of Jupiter itself from Juno will arrive in a few
weeks. For more than a year and a half, the spacecraft will circle the
gas giant, studying its huge auroras and peaking beneath its dense
clouds to learn more about the planet's structure and maybe even look
for signs of crazy sci-fi creatures inhabiting its atmosphere or unseen oceans.
After traveling five years through the solar system, Juno has finally
reached its destination and is currently in orbit around Jupiter,
traveling nearly 250,000 kilometers per hour (150,000 mph).
The most dangerous aspect of the $1.13 billion mission, which launched in 2011, occurred this evening at 11:18 pm ET when Juno initiated
its final approach procedures. In order to successfully insert itself
into orbit around Jupiter (instead of flying right past the planet, or
crashing into it), Juno needed to ignite its main engine for 35 minutes.
Now that Juno has successfully completed this burn, it will begin its first of 37 orbits around Jupiter.
Jupiter imaged by the Cassini spacecraft / Image courtesy of NASA
During these orbits, Juno will repeatedly dive through Jupiter’s
radiation belts, coming within 3,000 miles of Jupiter’s cloud tops at
its closest approach. With a suite of scientific instruments, Juno will provide data to improve our understanding of Jupiter’s formation and evolution.
“Juno’s study of Jupiter will help us to understand the
history of our own solar system and provide new insight into how
planetary systems form and develop in our galaxy and beyond.” – NASA Jet
Propulsion Laboratory
Juno, which was named after the Roman goddess who was Jupiter’s wife,
will enable scientists to see below Jupiter’s dense cloud cover –
something that’s never been done before.
One of the reasons this is such a unique mission is because its
destination is extremely dangerous. Of the eight known planets in the
solar system, Jupiter has the largest magnetic field and the highest
radiation. Because of this, Juno had to be specially designed to survive
these extremes long enough to retrieve useful data from this mysterious
planet.
To put the extremes of Jupiter in perspective, the background
radiation that we’re exposed to here on Earth is about 0.39 RAD. On
Jupiter, Juno is expected to see 20,000,000 RAD over the course of its
lifetime.
In NASA’s trailer for the Juno mission, scientists describe Jupiter as an unforgiving, relentless monster.
“It’s spinning around so fast that its gravity is like a
giant slingshot slinging rocks and dust, electrons and whole comets.
Anything that gets close to it becomes its weapon.” – NASA Juno Science
Team
Juno spacecraft size in relation to a basketball court / Image courtesy of NASA/JPL
NASA’s needed a spacecraft strong enough to withstand this
environment and their answer was Juno: a nearly 8,000 pound spacecraft
with three different solar panels that stretch out to 9 meters in
length.
At the beginning of the Jupiter orbit insertion, Juno carried 1,232
kilograms of fuel. Now that the 35-minute insertion burn has been
completed, there’s only 447 kilograms of fuel left on the spacecraft.
Juno will use the remaining fuel to complete the next 36 orbits around
Jupiter and ultimately de-orbit into the planet itself.
The video above shows a peek of what the spacecraft saw as it neared
its final approach. Captured with the JunoCam camera on June 29th,
Jupiter along with four of its moons (Callisto, Ganymede, Europa, and
Io) can be seen. All equipment on board, including the science
instruments and JunoCam, were turned off on June 30th to prepare the spacecraft for the most dangerous part of its mission: the Jupiter orbit insertion.
“The scariest thing to me about Juno are the unknowns. So
much about the environment that it will have to withstand is unknown.
Nothings really certain about what’s going to happen.” – NASA Juno
Science Team
There’s still a long, dangerous road ahead for Juno, but if
everything else goes as planned, the mission will end with the
spacecraft de-orbiting and crashing into Jupiter in 2018.
