Dawn

MORE

ON THIS PAGE

    The Latest

    The Latest

    Nov. 1, 2018: 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.

    The Dawn spacecraft launched 11 years ago and completed an extended mission to explore the two largest objects in the main asteroid belt—asteroid Vesta and dwarf planet Ceres. The inert spacecraft will remain orbit around Ceres for decades.

    10 Things to Know About Dawn

    10 Things to Know About Dawn

    1

    Two-for-One First

    Dawn was the first spacecraft to orbit two extraterrestrial destinations (Vesta and Ceres).

    2

    And ... First Orbit

    When Dawn arrived at Vesta, it became the first spacecraft to orbit an object in the main asteroid belt

    3

    And ... First Look

    When Dawn arrived at Ceres, it was the first spacecraft to visit a dwarf planet

    Full View of Vesta

    4

    Location, Location, Location

    Dawn showed us that location was key to how the early system organized and evolved.

    5

    Ocean Worlds

    Dawn reinforced that dwarf planets, not just icy moons, could have hosted oceans during a large part of their historyand potentially still do.

    6

    Building Blocks of Life

    Dawn found organics at Ceres and left us wanting to know more.

    7

    Science Fiction to Fact

    Star Wars’ far-ranging “TIE” fighters stand for “twin ion engine.” Thanks to its own ion engines, Dawn broke several exploration records.

    8

    More than a Space Rock

    Dawn found Vesta was a more varied world than scientists expected.

    9

    Bright Spots

    Dawn revealed that Ceres is geologically active—or was very recently.

    10

    Science to the End

    Dawn gathered science data at Ceres and returned it to Earth right up to the point the spacecraft ran out of fuel.

    Last Look at Ceres

    Major Engineering Achievements

    Major Engineering Achievements

    • First space mission to orbit two destinations
    • Record-breaking use of solar-electric propulsion: 25,700 mph, 2.7x any prior spacecraft and nearly equal to the velocity provided by Dawn’s Delta launch vehicle
    • Active powered flight: 5.9 years (54% of the time in space as of Sep. 7, 2018)

    Key Mission Findings

    Key Mission Findings

    Dawn orbited Vesta for more than a year, from July 2011 to September 2012. Its investigation confirmed that Vesta is the parent of the HED (howardites, eucrites, and diogenites) meteorites, which Dawn connected to Vesta’s large south polar basin, a priceless cosmic connection between samples in hand and a singular event on a small planet. Vesta is small enough (about the same size as Saturn's moon Enceladus) to have been deeply scarred by the Rheasilvia impact that launched the HEDs, but large enough to have differentiated into an iron core, silicate mantle, and igneous crust. Dawn also found hydrated and carbon rich material on its surface supplied by impactors, a result that was unexpected based on pre-Dawn telescopic observations.

    After its escape from Vesta and its journey onward, Dawn entered orbit around Ceres in March 2015. Dawn discovered that the inner solar system’s only dwarf planet was an ocean world where water and ammonia reacted with silicate rocks. As the ocean froze, salts and other telltale minerals concentrated into deposits that are now exposed in many locations across the surface. Dawn also found organics in several locations on Ceres’ surface.

    Key Mission Events

    Key Mission Events

    2007 — Launch (September)

    2009 — Mars Gravity Assist (February)

    2011 — Vesta Arrival (July)

    2012 — Vesta Departure (September)

    2015 — Ceres Arrival (March)

    2016 — End of prime mission (June)

    2016 — Start of first extension (July)

    2017 — Start of second extension (November)

    View the mission timeline ›

    Notable Explorers

    Quick Facts

    Quick Facts

    Type: Orbiter

    Status: Successful

    Launch Date: Sept. 27, 2007 | 11:34 UTC

    Launch Location: Cape Canaveral Air Force Station, Florida

    Destinations: Vesta and Ceres

    More ›

    Infographic showing stats about the Dawn mission

    More to Explore

    • Spacecraft

      View image gallery of NASA's Dawn spacecraft.

    • Vesta

      View image gallery of the second-largest world in the asteroid belt.

    • Ceres

      View image gallery of the dwarf planet Ceres.

    More Resources

    More Resources

    Solar System News