On June 10, 2021, the European Space Agency (ESA) announced the selection of EnVision as its newest medium-class science mission. EnVision will make detailed observations of Venus to understand its history and especially understand the connections between the atmosphere and geologic processes. As a key partner in the mission, NASA provides the Synthetic Aperture Radar, called VenSAR, to make high resolution measurements of the planet’s surface features.
Artist rendering of ESA's EnVision spacecraft. Credits: European Space Agency/Paris Observatory/VR2Planets
With significantly higher resolution than that of NASA’s Magellan mission,
which captured images of Venus in the early 1990s, VenSAR will improve our
understanding of the planet’s surface features. Repeated observations and
comparisons with Magellan imagery promise the opportunity for planetary
scientists to detect volcanic, tectonic and geomorphic changes over multiple
time scales at a resolution that gets to the level of individual
landslides. Scott Hensley of NASA’s Jet
Propulsion Laboratory in Southern California, is the instrument project
scientist.
“EnVision’s VenSAR will provide a unique perspective with its targeted
studies of the Venus surface, enriching the roadmap of Venus exploration,” said
Adriana Ocampo, EnVision Program Scientist at NASA HQ.
The image shows Earth (left) and Venus (right), and how similar they are in size. How did these sister planets evolve to end up so different? The EnVision mission (spacecraft render in image) aims to answer some of these key questions, and the NASA-provided EnVision Venus Synthetic Aperture Radar (VenSAR) will play a center role. The VenSAR will be built and operated by JPL. Credits: European Space Agency / Paris Observatory / VR2Planets
This video describes the deployment of EnVision's instruments VenSAR and SRS, as well as some basic spacecraft operations. VenSAR is a Synthetic Aperture Radar, and will map the surface of Venus using a range of modes including imaging at spatial resolutions of 10 m to 30 m, altimetry, polarimetry and radiometry. The Subsurface Sounding Radar (SRS) will penetrate into the top kilometre of the subsurface, and search for underground layering and buried boundaries. Three spectrometers (VenSpec-U, VenSpec-H and VenSpec-M), operating in the ultraviolet and infrared, will map trace gases, including searching for volcanic gas plumes, above and below the clouds, and map surface composition. A gravity and radio science investigation will use radio tracking to map the planet’s gravity field, constraining internal structure, and will measure atmospheric properties through radio occultation. Credits: European Space Agency / Paris Observatory / VR2Planets
In a “triple crown” moment for the Venus science community, the new
mission to Venus comes at a time when NASA has just announced their upcoming DAVINCI+ (Deep
Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging)
and VERITAS (Venus Emissivity, Radio Science, InSAR, Topography, and
Spectroscopy) missions. Working in concert, the trio of new spacecraft will
provide the most comprehensive study of Venus ever.
“I am delighted that the synergistic capabilities of these three new
missions will transform our fundamental understanding of Venus,” said Lori
Glaze, director of NASA’s Planetary Science Division at the agency’s
headquarters in Washington, DC. “ESA’s EnVision mission will provide
unparalleled high-resolution imaging and polarimetry capabilities. High-resolution
images of many dynamic processes at Mars profoundly changed the way we thought
about the Red Planet and images at similar scales have the potential to do the
same for Venus.”
The new observations can also tell us about Venus’ evolution. “The combined
results of EnVision and our Discovery missions will tell us how the forces of
volcanism, tectonics and chemical weathering joined together to create and
sustain Venus’ runaway hothouse climate,” said Tom Wagner, NASA’s Discovery
Program scientist at NASA HQ.
Of the three missions, the DAVINCI+ atmospheric entry probe can provide the
only direct measurements of the Venus atmosphere – for the first time since
NASA’s Pioneer Venus probe in 1978 and the USSR VEGA Balloons in 1985. Many of
the proposed measurements are of highest decadal priority and can only be
acquired by traveling directly through the planet’s harsh atmosphere.
The global topography data generated by VERITAS is also a unique
contribution among the three missions. It will provide scientists with
high-resolution topography and a global location map for Venus that will serve
as a reference system for all past and future surface data collected.
NASA is a partner with ESA on the EnVision mission. JPL, a division of
Caltech in Pasadena, California, will provide the VenSAR radar and will have
responsibility of the overall instrument management and provision. EnVision
VenSAR is part of NASA’s Discovery Program. And, NASA’s Marshall Space Flight
Center in Huntsville, Alabama, manages the Discovery Program for the agency’s
Science Mission Directorate in Washington, D.C.
For more information about NASA’s planetary science, visit: https://www.nasa.gov/solarsystem
For more information about ESA’s Cosmic Vision plan, visit: https://sci.esa.int/web/cosmic-vision/-/46510-cosmic-vision
Source: https://www.nasa.gov/feature/then-there-were-3-nasa-to-collaborate-on-esa-s-new-venus-mission
No comments:
Post a Comment