PHOTO: NASA/SDO. GRAPHIC: DAISY CHUNG, NGM STAFF
SOURCE: JOHNS HOPKINS UNIVERSITY APPLIED PHYSICS LABORATORY
| EXPLORE | SPACE
NASA has embarked on many successful
missions—from rocketing astronauts to
the moon to launching the first space-
craft to reach interstellar space. But it
hasn’t yet sent a mission to the sun. The
deterrent? Our nearest star’s searing heat.
The surface of the sun is 10,000°F, but
its outer atmosphere—the corona—soars
to some 3.5 million degrees Fahrenheit.
“This temperature inversion is a big mys-
tery that no one has been able to explain,”
says Nicola Fox, project scientist for the
Parker Solar Probe, the NASA mission
that aims to finally get close to the sun.
The mission is made possible now by a
shield constructed from a carbon-carbon
composite, which will keep the probe’s
instruments safe in the 70-degree range.
Launching as early as July 31, 2018, the
probe will make 24 orbits of the sun. It
will get within four million miles of the
star with the gravitational assist of seven
Venus flybys. That’s close enough to find
answers to the sun’s other big mystery:
what creates the solar wind, the charged
particles that accelerate from the sun and
wreak havoc on Earth’s electrical systems.
“We see the sun every day, but we don’t
know much about it,” says Fox. “The sun
is the last major place for us to go.”
MISSION INTO THE
HEAT OF THE SUN
By Rachel Hartigan Shea
SUNMERCURYVEN
USEAR
THLaunch
July 31,
2018First closest
approach
Dec. 19, 2024)LUVW9HQXVƄ\E\
Sept. 28, 2018Thermal shield
Protects the probe from temperatures
nearing 2500∞F. The carbon-carbon
composite shield is eight feet wide
and just 4.5 inches thick.Magnetometers
0HDVXUHPDJQHWLFƃHOGRIFRURQDIURPYDULRXVVSRWVRQERRP:LGHƃHOGLPDJHU
Captures images of sunís corona and solar wind.
Charged-particle detector
$QDO\]HVRULJLQVSHHGDQGPRYHPHQWRISDUWLFOHVSolar panels
Generate power.Solar-probe cup
Measures speed, density, and
temperature of solar wind.PARKER SOLAR PROBE