Juno

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Table of Contents:
• Mission Overview
• Timeline
• Scientific Objectives
• Spacecraft &
Instruments
• Equipment
• Links
MISSION OVERVIEW
Juno’s principal goal is to
understand the origin and evolution
of Jupiter. Underneath its dense
cloud cover, Jupiter safeguards
secrets to the fundamental
processes and conditions that
governed our solar system during its
formation. As our primary example
of a giant planet, Jupiter can also
provide critical knowledge for
understanding the planetary
systems being discovered around
other stars.
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MISSION OVERVIEW
The Juno spacecraft will
investigate Jupiter's origins, its
interior structure, its deep
atmosphere and its
magnetosphere from an innovative,
highly elliptical orbit with a suite of
seven science instruments. In
addition, a camera called JunoCam
will be used by student participants
in the Juno Education and Public
Outreach program to take the first
images of Jupiter's polar regions.
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TIMELINE
• August 5, 2011: Juno
spacecraft launches
• October 9, 2013: Earth flyby
gravity assist
• July 5, 2016: Juno spacecraft
arrives at Jupiter
• Oct 2017: Juno will end
operations.
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SCIENTIFIC OBJECTIVES
Origin – Jupiter’s solid core and
abundance of heavy metals in the
atmosphere make it an ideal model to
understand the origin of giant planets.
Juno will measure global abundances of
oxygen and nitrogen by mapping the
gravitational field and using microwave
observations of water and ammonia.
Interior – Juno will map Jupiter’s
gravitation and magnetic fields,
revealing the interior structure, the origin
of the magnetic field, the mass of its
core, the nature of deep convection, and
the abundance of water.
SCIENTIFIC OBJECTIVES
Atmosphere – Jupiter has the most massive
atmosphere of all the planets. By mapping
variations in atmospheric composition,
temperature, cloud opacity and dynamics,
Juno will determine the global structure and
dynamics of Jupiter’s atmosphere below the
cloud tops for the first time.
Magnetosphere – Jupiter’s powerful
magnetospheric dynamics create the brightest
aurora in our solar system. Juno will measure
the distribution of the charged particles, their
associated fields, and the concurrent UV
emissions of the planet’s polar
magnetosphere, greatly improving our
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understanding of this remarkable phenomena.
SPACECRAFT
For Juno, like NASA’s earlier Pioneer
spacecraft, spinning makes the
spacecraft's pointing extremely stable
and easy to control. Just after launch,
and before its solar arrays are
deployed, Juno will be spun-up by
rocket motors on its still attached
second-stage rocket booster. While in
orbit at Jupiter, the spinning
spacecraft sweeps the fields of view
of its instruments through space once
for each rotation. At three rotations
per minute, the instruments' fields of
view sweep across Jupiter about 400
times in the two hours it takes to fly
from pole to pole.
SPACECRAFT
Jupiter’s orbit is five times farther
from the Sun than Earth’s, so the
giant planet receives 25 times less
sunlight than Earth. Juno will be the
first solar-powered spacecraft
designed to operate at such a great
distance from the sun.
Three solar panels extend outward
from Juno’s hexagonal body, giving
the overall spacecraft a span of more
than 66 feet (20 meters). The solar
panels will remain in sunlight
continuously from launch through end
of mission, except for a few minutes
during the Earth flyby.
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SPACECRAFT
Jupiter’s orbit is five times farther
from the Sun than Earth’s, so the
giant planet receives 25 times less
sunlight than Earth. Juno will be the
first solar-powered spacecraft
designed to operate at such a great
distance from the sun.
Three solar panels extend outward
from Juno’s hexagonal body, giving
the overall spacecraft a span of
more than 66 feet (20 meters). The
solar panels will remain in sunlight
continuously from launch through
end of mission, except for a few
minutes during the Earth flyby.
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SPACECRAFT
Juno will avoid Jupiter's highest
radiation regions by approaching
over the north, dropping to an
altitude below the planet's
radiation belts – which are
analogous to Earth’s Van Allen
belts, but far more deadly – and
then exiting over the south. To
protect sensitive spacecraft
electronics, Juno will carry the
first radiation shielded
electronics vault, a critical
feature for enabling sustained
exploration in such a heavy
radiation environment.
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Spacecraft Instruments
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Magnetometer
Microwave Radiometer
Plasma Waves Instrument
Jovian Infrared Auroral Mapper
JunoCam
Ultraviolet Spectrograph
JEDI
Jade
Gravity Science
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Magnetometer/Advanced Stellar Compass
The magnetic field
investigation has three
goals: mapping of the
magnetic field, determining
the dynamics of Jupiter's
interior, and determination
of the three-dimensional
structure of the polar
magnetosphere. To achieve
these goals, the mission
employs a Flux Gate
Magnetometer and an
Advanced Stellar Compass
(ASC) to provide accurate
pointing information of the
Juno spacecraft for precise
mapping.
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Microwave Radiometer
The primary goal of the Juno
Microwave Radiometer is to
probe the deep atmosphere
of Jupiter at radio
wavelengths using six
separate radiometers to
measure the planet's thermal
emissions. The MWR
experiment will provide
answers to two key
questions: How did Jupiter
form? and How deep is the
atmospheric circulation that
was measured from the
Galileo Probe down to 22
Earth atmospheric pressures
at sea level, and at the cloud
top level from imaging data
returned by other missions?
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Plasma Waves Instrument
Plasma Waves
Instrument will
measure plasma
waves and radio
waves in Jupiter’s
magnetosphere.
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Jovian Infrared Auroral Mapper
The primary goal of
JIRAM is to probe the
upper layers of
Jupiter's atmosphere
down to pressures of
5-7 Earth atmospheric
pressure at sea level
using an imager and
a spectrometer.
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JunoCam
The mission of
JunoCam will be to
provide views of
Jupiter's polar region
and very low latitude
cloud belts.
JunoCam is to
facilitate education
and public outreach.
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Ultraviolet Spectrograph
Ultraviolet
Spectrograph is
an imaging
spectrograph
that is sensitive
to ultraviolet
emissions.
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Jupiter Energetic-particle Detector Instrument
JEDI is a suite of
detectors that will
measure the
energy and
angular
distribution of
charged particles.
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Jovian Auroral Distributions Experiment
Jade will measure
the distribution of
electrons and the
velocity distribution
and composition of
ions.
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Gravity Science
The Juno Gravity
Science
Investigation will
probe the mass
properties of
Jupiter by using
the
communication
subsystem to
perform Doppler
tracking.
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LINKS
Additional information:
• http://www.nasa.gov/mission_pa
ges/juno/main/index.html
• http://newfrontiers.nasa.gov/mis
sions_juno.html
• http://juno.wisc.edu/mission.html
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Resources:
http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/37654/1/05-2760.pdf
http://www.nasa.gov/mission_pages/juno/main/index.html
http://en.wikipedia.org/wiki/Juno_(spacecraft)
http://www.jpl.nasa.gov/news/fact_sheets/JUNOFactSheet2009_sm.pdf
http://www.jpl.nasa.gov/missions/missiondetails.cfm?mission=Juno
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