Dawn’s Latest Orbit Reveals Dramatic New Views of Occator Crater

This mosaic of a prominent mound located on the western side of Cerealia Facula was obtained by NASA’s Dawn spacecraft on June 22, 2018 from an altitude of about 21 miles (34 kilometers). (Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA)

PASADENA, Calif. (NASA PR) — NASA’s Dawn spacecraft reached its lowest-ever and final orbit around dwarf planet Ceres on June 6 and has been returning thousands of stunning images and other data.

The flight team maneuvered the spacecraft into an orbit that dives 22 miles (35 kilometers) above the surface of Ceres and viewed Occator Crater, site of the famous bright deposits, and other intriguing regions. In more than three years of orbiting Ceres, Dawn’s lowest altitude before this month was 240 miles (385 kilometers), so the data from this current orbit bring the dwarf planet into much sharper focus.

These low orbits have revealed unprecedented details of the relationships between bright and dark materials in the region of Vinalia Faculae. Dawn’s visible and infrared mapping spectrometer had previously found the bright deposits to be made of sodium carbonate, a material commonly found in evaporite deposits on Earth. Last week Dawn fired its ion engine, possibly for the final time, to fly nearer Cerealia Facula, the large deposit of sodium carbonate in the center of Occator Crater.

“Acquiring these spectacular pictures has been one of the greatest challenges in Dawn’s extraordinary extraterrestrial expedition, and the results are better than we had ever hoped,” said Dawn’s chief engineer and project manager, Marc Rayman, of NASA’s Jet Propulsion Laboratory, Pasadena, California. “Dawn is like a master artist, adding rich details to the otherworldly beauty in its intimate portrait of Ceres.”

The wealth of information contained in these images, and more that are planned in the coming weeks, will help address key, open questions about the origin of the faculae, the largest deposits of carbonates observed thus far outside Earth, and possibly Mars. In particular, scientists have been wondering how that material was exposed, either from a shallow, sub-surface reservoir of mineral-laden water, or from a deeper source of brines (liquid water enriched in salts) percolating upward through fractures.

And the low-altitude observations obtained with Dawn’s other instruments, a gamma ray and neutron detector and a visible and infrared mapping spectrometer, will reveal the composition of Ceres at finer scale, shedding new light on the origin of the materials found across Ceres’ surface. New gravity measurements also may reveal details of the subsurface.

This close-up image of the Vinalia Faculae in Occator Crater was obtained by NASA’s Dawn spacecraft on June 14, 2018 from an altitude of about 24 miles (39 kilometers). (Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA)

“The first views of Ceres obtained by Dawn beckoned us with a single, blinding bright spot,” said Carol Raymond of JPL, Dawn’s principal investigator. “Unraveling the nature and history of this fascinating dwarf planet during the course of Dawn’s extended stay at Ceres has been thrilling, and it is especially fitting that Dawn’s last act will provide rich new data sets to test those theories.”

See more images from Dawn’s low orbits here.

Read more details about Dawn’s recent orbits in Rayman’s Dawn Journal.

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. Orbital ATK Inc., 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.

For a complete list of mission participants, visit:

https://dawn.jpl.nasa.gov/mission

More information about Dawn is available at the following sites:

https://www.nasa.gov/dawn

https://dawn.jpl.nasa.gov

  • While visiting a third rock would have been cool, I don’t think anyone will be disappointed by the close ups Dawn takes and additional lessons we learn from staying at Ceres.

  • ThomasLMatula

    Hopefully the orbit for it is stable enough that it won’t impact and contaminate the surface with organics as I don’t believed it was sterilized before launch.

  • Andrew Tubbiolo

    Wow, looks like cryo-volcanism. So there’s liquid something, probably water deep down there. NICE!

  • ThomasLMatula

    And maybe life?

  • Andrew Tubbiolo

    Oh please I hope not. We need some sterility to mine without having to make the moral balance of wiping out a species or worry about contaminating our own biosphere. If there really is life everywhere hopefully we’re all family members and the biosphere is solar system wide and not just Earth centric. Hopefully with that we’re not toxic to each other.

  • ThomasLMatula

    Actually if you have the technology to reach Ceres there are a lot more attractive asteroids to mine. Easier as well. So I wouldn’t see any problems making it a science preserve.

  • Andrew Tubbiolo

    I hope you’re wrong. 🙂 But I share a similar suspicion. If you’re right, we’re going to have to tread heavily on our weaker cousins again in order to move ahead. It would introduce a form of savagery a lot of people don’t want to move forward into this new frontier, but if life does exist on that scale, we’ll have to.

  • ThomasLMatula

    I don’t think it will be that hard. The smaller asteroids and moons, the ones without submerged oceans, will have plenty of resources including water for future space settlers, so it will be no great lost to skip the handful that show evidence of submerged oceans. Given the problems of microgravity I suspect most space habitats beyond Earth, Mars and the Moon will be in space. That said, the life bearing ocean worlds may well be a gold mine for bioprospectors, but the limited number of samples of microorganisms they would collect for research and to develop strains for producing the specific organic compounds of value should have no impact on their ecosystems.

  • Andrew Tubbiolo

    ….And we have plenty of time to get sterilization down to a fine science. It’s not biological depletion I’d worry about in your scenario of solar system development, it would be contamination. I suspect we’ve already done it to Mars. My bet is any Earth organisms on Mars are either overwhelmed by the locals or the environment. The number of contaminants are no doubt very small. And the it’s unlikely they’d overwhelm any Martian locals. Bring in a steady flow of people, and that calculus get’s turned on it’s head.

    BFR is a big leap in your direction. If most humans are going to live off world ships will need to be big, well shielded, and nice places to live. Family will have to intermingle with work. There could be some really positive social forces there. For a sizable crew/community we’ll need one or two more doublings for ship size over BFR, and a ship that big is either going to have a solar array the size of Manhattan Island (which is not crazy for a spaceship) or be powered and propelled by nuclear energy.