Dawn Goes Dark with Fuel Exhausted, Ending NASA’s 1st Mission to 2 Largest Asteroid Belt Worlds

Artist’s rendering shows
NASA’s Dawn spacecraft maneuvering above Ceres with its ion propulsion system.  Credits: NASA/JPL-Caltech

Ken Kremer — SpaceUpClose.com & RocketSTEM – – 6 November 2018


CAPE CANAVERAL,
FL –  NASA’s groundbreaking Dawn
spacecraft has gone dark after exhausting all its maneuvering fuel – thus ending
an 11-year mission to the two largest worlds in the main Asteroid Belt that are
fossilized remnants from the dawn of our Solar System.



Dawn is the first
spacecraft to orbit two worlds – Ceres & Vesta – enabled only by its unique
ion propulsion thruster system which is vastly more powerful than chemical
thrusters. 



The spacecraft first studied Vesta for 14
months, the second most massive asteroid in 2011 and 2012. Then it broke out of
orbit and set off for Ceres.



“Dawn’s unique mission to orbit and
explore two strange new worlds would have been impossible without ion
propulsion,” said Marc Rayman of NASA’s Jet Propulsion Laboratory,
Pasadena, California, who has served as Dawn’s mission director, chief engineer
and project manager. 



“Dawn is truly an interplanetary
spaceship, and it has been outstandingly productive as it introduced these
fascinating and mysterious worlds to Earth.”

High resolution mosaic of the side by side Cerealia Facula (left) and Vinalia
Faculae (right)
features shows the famous bright
spots of salt deposits inside Occator Crater on Ceres. It is based on images
obtained by NASA’s Dawn spacecraft in its second extended mission, from an
altitude as low as about 21 miles (34 kilometers) since June 2018. This stitched
mosaic reveals the intricate pattern between bright and dark material across these
flow features, which scientists will use to infer the history of this area, in
particular the role of the fractures in the exposure of bright salts onto the
surface.  Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/Ken
Kremer/kenkremer.com/Marco Di Lorenzo

Dawn was built by Orbital ATK, now Northrup Grumman and
launched on a ULA Delta II rocket from Florida on 27 September 2007
– which I witnessed from Jetty Park Pier, Port Canaveral, FL.



It swung by
Mars before arriving at its first target, Vesta, the second most massive object
in the asteroid belt. 

This context collage
shows the location of a prominent mound of the famous bright spots of salt
deposits located on the western side of Cerealia Facula (upper & lower right)
and
Vinalia Faculae (lower left) and inside Occator crater (upper left) on dwarf planet Ceres.
Newly obtained highest ever resolution images were taken of the bright salt
deposits inside Occator by NASA’s Dawn spacecraft since June 2018 from a record
low altitude of about 21 miles (34 kilometers) above Ceres, colorized mosaics.  Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/Ken
Kremer/kenkremer.com/Marco Di Lorenzo

Here is the NASA Press Release – until my story is ready:


NASA’s Dawn spacecraft has gone silent, ending a
historic mission that studied time capsules from the solar system’s earliest
chapter.



Dawn missed scheduled communications sessions
with NASA’s Deep Space Network on Wednesday, Oct. 31, and
Thursday, Nov. 1. After the flight team eliminated other possible causes for
the missed communications, mission managers concluded that the spacecraft
finally ran out of hydrazine, the fuel that enables the spacecraft to control
its pointing. Dawn can no longer keep its antennas trained on Earth to
communicate with mission control or turn its solar panels to the Sun to
recharge.



Video Caption: NASA’s Dawn spacecraft
turned science fiction into science fact by using ion propulsion to explore the
two largest bodies in the main asteroid belt, Vesta and Ceres. The mission ended
on. Nov. 1, 2018, when the spacecraft ran out of hydrazine, which keeps it
oriented and in communication with Earth. 
Credits:
NASA/JPL-Caltech




The Dawn spacecraft launched 11 years ago to visit the two largest
objects in the main asteroid belt. Currently, it’s in orbit around the dwarf
planet Ceres, where it will remain for decades.



“Today, we celebrate the end of our Dawn mission
– its incredible technical achievements, the vital science it gave us, and
the entire team who enabled the spacecraft to make these discoveries,” said
Thomas Zurbuchen, associate administrator of NASA’s Science Mission Directorate
in Washington. “The astounding images and data that Dawn collected from Vesta
and Ceres are critical to understanding the history and evolution of our solar
system.”

This photo of Ceres and
the bright regions of Occator Crater was one of the last views NASA’s Dawn
spacecraft transmitted before it completed its mission. This view, which faces
south, was captured on Sept. 1, 2018, at an altitude of 2,340 miles (3,370
kilometers) as the spacecraft was ascending in its elliptical orbit.  Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Dawn launched in 2007 on a journey that put
about 4.3 billion miles (6.9 billion kilometers) on its odometer. Propelled by
ion engines, the spacecraft achieved many firsts along the way. In 2011, when Dawn arrived at
Vesta, the second largest world in the main asteroid belt, the spacecraft
became the first to orbit a body in the region between Mars and Jupiter. In 2015,
when Dawn went into orbit around Ceres, a dwarf planet that is also the largest
world in the asteroid belt, the mission became the first to visit a dwarf
planet and go into orbit around two destinations beyond Earth.



The fact that my car’s license plate frame
proclaims, ‘My other vehicle is in the main asteroid belt,’ shows how much
pride I take in Dawn,” said Mission Director and Chief Engineer Marc
Rayman at NASA’s Jet Propulsion Laboratory (JPL). “The demands we put on
Dawn were tremendous, but it met the challenge every time. It’s hard to say
goodbye to this amazing spaceship, but it’s time.”
This photo of Ceres and
one of its key landmarks, Ahuna Mons, was one of the last views Dawn
transmitted before it completed its mission. This view, which faces south, was
captured on Sept. 1, 2018, at an altitude of 2220 miles (3570 kilometers) as
the spacecraft was ascending in its elliptical orbit.  Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA



The data Dawn beamed back to Earth from its four science experiments enabled scientists to
compare two planet-like worlds that evolved very differently. Among its
accomplishments, Dawn showed how important location was to the way objects in
the early solar system formed and evolved. Dawn also reinforced the idea that
dwarf planets could have hosted oceans over a significant part of their history
– and potentially still do.



“In many ways, Dawn’s
legacy
i­s just beginning,” said Princ­­ipal Investigator Carol
Raymond at JPL. “Dawn’s data sets will be deeply mined by scientists working on
how planets grow and differentiate, and when and where life could have formed
in our solar system. Ceres and Vesta are important to the study of distant
planetary systems, too, as they provide a glimpse of the conditions that may
exist around young stars.”



Because Ceres has conditions of interest to
scientists who study chemistry that leads to the development of life, NASA
follows strict planetary protection protocols for the disposal of the Dawn
spacecraft. Dawn will remain in orbit for at least 20 years,
and engineers have more than 99 percent confidence the orbit will last for at
least 50 years.



So, while the mission plan doesn’t provide the
closure of a final, fiery plunge – the way NASA’s Cassini spacecraft ended last year, for
example – at least this is certain: Dawn spent every last drop of hydrazine
making science observations of Ceres and radioing them back so we could learn
more about the solar system we call home.



The Dawn mission is managed by JPL for NASA’s
Science Mission Directorate in Washington. Dawn is a project of the
directorate’s Discovery Program, managed by NASA’s Marshall Space Flight Center
in Huntsville, Alabama. JPL is responsible for overall Dawn mission science.
Northrop Grumman in Dulles, Virginia, designed and built the spacecraft. The
German Aerospace Center, Max Planck Institute for Solar System Research,
Italian Space Agency and Italian National Astrophysical Institute are
international partners on the mission team.

NASA’s Dawn Asteroid orbiter
launches on United Launch Alliance Delta II Heavy rocket on September 27, 2007
from Launch Complex-17 on Cape Canaveral Air Force Station, FL.
Credit:
Ken Kremer/kenkremer.com/spaceupclose.com

Watch for Ken’s continuing onsite coverage of NASA, SpaceX, ULA,
Boeing, Lockheed Martin, Northrop Grumman and more space and mission reports
direct from the Kennedy Space Center, Cape Canaveral Air Force Station, Florida
and Wallops Flight Facility, Virginia.

Stay tuned here for Ken’s continuing Earth and Planetary science
and human spaceflight news: www.kenkremer.com –www.spaceupclose.com –
twitter @ken_kremer – email: ken at kenkremer.com
Dr. Kremer is a research
scientist and journalist based in the KSC area.
………….

Ken’s photos are for sale and he is available for lectures and outreach events

Ken Kremer

Watch for Ken’s continuing onsite coverage of NASA, SpaceX, ULA, Boeing, Lockheed Martin, Northrop Grumman and more space and mission reports direct from Kennedy Space Center and Cape Canaveral Air Force Station in Florida and Wallops Flight Facility in Virginia. Stay tuned here for Ken's continuing Earth and Planetary science and human spaceflight news. Dr. Kremer is a research scientist and journalist based in the KSC area, active in outreach and interviewed regularly on TV and radio about space topics. Ken’s photos are for sale and he is available for lectures and outreach events.

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