Laurel Kornfeld
March 9th, 2017
The bright spots of Occator Crater are shown in enhanced color in this view from NASAs Dawn spacecraft. Image Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/PSI/LPI
Researchers who studied images of Ceres Occator Crater captured by the Dawn spacecrafts scientific imaging system have determined that its bright spots, composed largely of carbonate salts, are significantly younger than the crater in which they sit.
The bright spots are also evidence that Ceres has experienced cryovolcanic outbursts over long periods of time, making Ceres the closest world to the Sun to have experienced cryovolcanism.
A science team at the Max Planck Institute for Solar System Research (MPS), which operates Dawns imaging instruments, analyzed images taken by the spacecraft between December 2015 and September 2016, the time period when it orbited just 233 miles (375 kilometers) above the dwarf planets surface.
Occator Crater, home of Ceres intriguing brightest areas, is prominently featured in this image from NASAs Dawn spacecraft. Image Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
At that close orbit, Dawns cameras were able to capture images with a resolution of just 115 feet (35 meters) per pixel. Detailed photos of Occator Crater, first observed when Dawn entered Ceres orbit in March 2015, show complex geological structures such as fractures, avalanches, and smaller craters within the large one.
Led by Andreas Nathues, Dawn Framing Camera lead investigator, researchers also studied measurements of the area taken by Dawns infrared VIR spectrometer.
Using the data, they determined the bright spots are approximately 4 million years old, making them 30 million years younger than Occator Crater.
The most reflective materials on Ceres surface, the bright spots initially puzzled astronomers who were uncertain about their composition.
With a diameter of 57 miles (92 kilometers), Occator Crater, located in Ceres northern hemisphere, contains a seven-mile (11-kilometer) wide pit in its center as well as steep slopes and jagged mountains at its edges that rise as high as 2,461 feet (750 meters).
A bright dome-shaped structure within the central pit rises 1,312 feet (400 meters). Fractures are visible along the structure of the 1.87-mile (three-km) wide dome.
In these data, the origin and evolution of the crater as it presents itself today can be read more clearly than ever before, Nathues said.
Based on the presence of the pit and the jagged ridges, researchers believe Occator Crater was created when an asteroid or comet impacted Ceres 34 million years ago.
The impact produced a central mountain within the crater that later collapsed and triggered cryovolcanic activity. Disruption caused by the impact allowed water as well as other dissolved gases, including methane and carbon dioxide, to form a vent system.
Surface fractures were created by eruptions of briny liquids through the vents, bringing with them the carbonate-rich materials that eventually formed the dome.
Scientists believe the dome formed over a long period of time and not as the result of a single event.
The deposits in Occator Crater are composed of carbonate-rich salts. In contrast, other bright spots scattered around the craters edges, thinner and less bright, are a mixture of carbonates and other, darker materials.
By counting and measuring the smaller craters within Occator Crater produced by later impacts scientists were able to determine the ages of both the bright spots and of Occator.
The age and the appearance of the material surrounding the bright dome indicate that Cerealia Facula (the bright spots) was formed by a recurring, eruptive process, which also hurled material into more outward regions of the central pit, Nathues said, noting that similar dome structures have been found on Jupiters moons Ganymede and Callisto.
The surface of the dome was likely created in the most recent eruptions within the crater.
Cryovolcanic activity may still be occurring in Occator Crater, though at a far less intense level than in the past. Images of the crater taken at specific angles reveal a haze scientists view as coming from the sublimation of water.
Earlier images captured by Dawn from higher orbits show regular changes in the craters brightness.
The nature of the light scattering at the bottom of Occator differs fundamentally from that at other parts of the Ceres surface, said MPS scientist Guneshwar Singh Thangjam.The most likely explanation is that near the crater floor, an optically thin, semi-transparent haze is formed.
Researchers think the haze formed by water coming from fractures in the crater floor sublimating in the presence of sunlight.
Dawn is now headed to a different orbital plane and a higher altitude of 12,400 miles (20,000 kilometers).
Video courtesy of JPL
Tagged: Ceres cryovolcanism Dawn Occator Crater The Range
Laurel Kornfeld is an amateur astronomer and freelance writer from Highland Park, NJ, who enjoys writing about astronomy and planetary science. She studied journalism at Douglass College, Rutgers University, and earned a Graduate Certificate of Science from Swinburne Universitys Astronomy Online program. Her writings have been published online in The Atlantic, Astronomy magazines guest blog section, the UK Space Conference, the 2009 IAU General Assembly newspaper, The Space Reporter, and newsletters of various astronomy clubs. She is a member of the Cranford, NJ-based Amateur Astronomers, Inc. Especially interested in the outer solar system, Laurel gave a brief presentation at the 2008 Great Planet Debate held at the Johns Hopkins University Applied Physics Lab in Laurel, MD.
Read the original here:
Ceres' bright spots significantly younger than crater they inhabit - SpaceFlight Insider
- Armadillo’s Level 2 LLC attempt coming soon? - November 8th, 2009 [November 8th, 2009]
- Decisions, decisions - November 8th, 2009 [November 8th, 2009]
- Armadillo versus the weather - November 8th, 2009 [November 8th, 2009]
- Photos from Armadillo’s Saturday flights - November 8th, 2009 [November 8th, 2009]
- Armadillo Level 2 Flight 1 - November 8th, 2009 [November 8th, 2009]
- Meanwhile, elsewhere in the LLC race - November 8th, 2009 [November 8th, 2009]
- Masten gets halfway there - November 8th, 2009 [November 8th, 2009]
- Xombie photos (finally!) - November 8th, 2009 [November 8th, 2009]
- Is the media clowning around? - November 8th, 2009 [November 8th, 2009]
- Galactic Suite “on schedule”? - November 8th, 2009 [November 8th, 2009]
- Scientist Guest Column: Using Commercial Suborbital Spacecraft for Microgravity Chemistry Research - November 8th, 2009 [November 8th, 2009]
- Building Spaceport Infrastructure: An Overview of the STIM-Grants Program - November 8th, 2009 [November 8th, 2009]
- Five Years After SpaceShipOne’s Historic X PRIZE Flight, New Challenges Await - November 8th, 2009 [November 8th, 2009]
- Masten Space Systems Makes Successful Flights to Qualify for $150K NASA Lunar Lander Prize Level 1 - November 8th, 2009 [November 8th, 2009]
- Distinguished Former NASA Astronauts Endorse Commercial Spaceflight in Wall Street Journal Op-Ed - November 8th, 2009 [November 8th, 2009]
- NASA Chief Praises Commercial Spaceflight, Suborbital Science, & Innovation Prizes in Speech - November 8th, 2009 [November 8th, 2009]
- CSF Welcomes Strong Support for Commercial Human Spaceflight in White House Panel’s Report - November 8th, 2009 [November 8th, 2009]
- Commercial Spaceflight Federation President Bretton Alexander Appointed to the NASA Advisory Council - November 8th, 2009 [November 8th, 2009]
- In November 5th Public Ceremony, NASA to Award $1.65 Million In Prizes for Commercial Spaceflight Successes - November 8th, 2009 [November 8th, 2009]
- CSF Congratulates Winners of NASA’s $2 Million Lunar Lander Challenge - November 8th, 2009 [November 8th, 2009]
- Welcome to the NewSpace Journal - December 13th, 2009 [December 13th, 2009]
- Some things even Virgin can’t control - December 13th, 2009 [December 13th, 2009]
- While you’re waiting for the rollout… - December 13th, 2009 [December 13th, 2009]
- SpaceShipTwo rollout: initial impressions - December 13th, 2009 [December 13th, 2009]
- A couple of pics - December 13th, 2009 [December 13th, 2009]
- SpaceShipTwo slideshow - December 13th, 2009 [December 13th, 2009]
- The Virgin party’s aftermath - December 13th, 2009 [December 13th, 2009]
- Investment in Commercial Spaceflight Grows to $1.46 Billion, Updated Industry Study Reveals - December 13th, 2009 [December 13th, 2009]
- Former Astronaut-Astronomer, Sam Durrance, Joins the CSF Suborbital Researchers Group - December 13th, 2009 [December 13th, 2009]
- Commercial Spaceflight Federation Announces Creation and Initial Membership of Spaceports Council - December 13th, 2009 [December 13th, 2009]
- CSF President Bretton Alexander Testifies Before House Science Committee on Spaceflight Safety - December 13th, 2009 [December 13th, 2009]
- CSF Vice-Chairman Jeff Greason Testifies Before House Transportation and Infrastructure Committee on Commercial Spaceflight Regulation - December 13th, 2009 [December 13th, 2009]
- Virgin Galactic Unveils SpaceShipTwo - December 13th, 2009 [December 13th, 2009]
- So that’s why Aabar invested in Virgin? - December 15th, 2009 [December 15th, 2009]
- More about the Virgin rollout aftermath - December 17th, 2009 [December 17th, 2009]
- Space tourism as “the final undiscovered frontier”? - December 17th, 2009 [December 17th, 2009]
- Orion Propulsion acquired - December 17th, 2009 [December 17th, 2009]
- Spaceport America developments - December 18th, 2009 [December 18th, 2009]
- XCOR wins a major customer - December 19th, 2009 [December 19th, 2009]
- Centennial Challenges, Spaceport Infrastructure Grants, and Suborbital Science to Receive Funds from NASA and FAA - December 22nd, 2009 [December 22nd, 2009]
- Video tour of Spaceport America - December 24th, 2009 [December 24th, 2009]
- Virgin’s web traffic planning - December 24th, 2009 [December 24th, 2009]
- List of Speakers Announced for the Next-Generation Suborbital Researchers Conference in February - December 31st, 2009 [December 31st, 2009]
- Popular Science Features Commercial Spaceflight on January Cover, Discusses NASA Partnerships - January 4th, 2010 [January 4th, 2010]
- Aviation Week honors the “Space Entrepreneur” - January 5th, 2010 [January 5th, 2010]
- “The Space Entrepreneur” Named by Aviation Week Magazine As Its 2009 Person of the Year - January 5th, 2010 [January 5th, 2010]
- Additional notes about Olsen’s book - January 6th, 2010 [January 6th, 2010]
- Registration deadline approaching for suborbital science conference - January 8th, 2010 [January 8th, 2010]
- NASA Deputy Administrator Lori Garver to Keynote the Next-Generation Suborbital Researchers Conference in February - January 11th, 2010 [January 11th, 2010]
- Cecil Field gets spaceport license – but will anyone use it? - January 12th, 2010 [January 12th, 2010]
- Training begins for suborbital scientist-astronauts - January 12th, 2010 [January 12th, 2010]
- First Class of Suborbital Scientist-Astronauts Successfully Complete NASTAR Training Program - January 14th, 2010 [January 14th, 2010]
- Is “space tour guide” in your professional future? - January 17th, 2010 [January 17th, 2010]
- What can Florida, Indiana, and others learn from Oklahoma? - January 17th, 2010 [January 17th, 2010]
- Virginia wants money, New Mexico wants laws - January 21st, 2010 [January 21st, 2010]
- Commercial Spaceflight Federation Responds to the Aerospace Safety Advisory Panel’s 2009 Annual Report - January 21st, 2010 [January 21st, 2010]
- CSF Statement on NASA’s Anticipated Announcement of a $6 Billion Commercial Crew Program and NASA Budget Increase - January 29th, 2010 [January 29th, 2010]
- CSF Welcomes New NASA Human Spaceflight Plan, Congratulates Commercial Crew Development Winners - February 1st, 2010 [February 1st, 2010]
- NASA Unveils Commercial Human Spaceflight Development Agreements and Announces $50 Million in Seed Funding for Commercial Crew - February 3rd, 2010 [February 3rd, 2010]
- James Cameron Endorses Commercial Spaceflight, New NASA Plan - February 4th, 2010 [February 4th, 2010]
- Newt Gingrich and Bob Walker Endorse Obama’s New NASA Plan, Urge Bipartisan Support - February 13th, 2010 [February 13th, 2010]
- Blue Origin proposes orbital vehicle - February 18th, 2010 [February 18th, 2010]
- CSF Announces New Research and Education Affiliates Program, Initial Participating Universities - February 18th, 2010 [February 18th, 2010]
- CSF Welcomes Historic NASA Commitment of $75 Million for Commercial Suborbital Flights, Payloads - February 18th, 2010 [February 18th, 2010]
- Suborbital vehicle development updates - February 19th, 2010 [February 19th, 2010]
- Other conference announcements - February 21st, 2010 [February 21st, 2010]
- Bigger prizes to come? - February 23rd, 2010 [February 23rd, 2010]
- Gov. Bill Richardson Endorses Commercial Spaceflight, Obama’s New NASA Plan - February 23rd, 2010 [February 23rd, 2010]
- Over 250 People Attend Next-Gen Suborbital Researchers Conference, 2011 Meeting Planned for Florida - February 24th, 2010 [February 24th, 2010]
- Boston Globe, Nature, New York Times Editorial Boards Among Others Welcoming New NASA Plan - February 25th, 2010 [February 25th, 2010]
- Commercial Spaceflight Federation Commends New Mexico for Passage of Key Liability Legislation - March 2nd, 2010 [March 2nd, 2010]
- Burt Rutan’s BigThink - March 3rd, 2010 [March 3rd, 2010]
- Brief notes: Soyuz, Virgin, and… iCarly? - March 5th, 2010 [March 5th, 2010]
- Commercial Spaceflight Federation 2009 Annual Report Highlights Industry Progress - March 8th, 2010 [March 8th, 2010]
- SpaceShipTwo flies, on schedule - March 23rd, 2010 [March 23rd, 2010]
- SpaceShipTwo captive carry flight video - March 23rd, 2010 [March 23rd, 2010]
- Over the Mojave Desert, Suborbital Vehicles Take Flight - March 28th, 2010 [March 28th, 2010]
- See WK2 and SS2 fly in New Mexico this October - March 29th, 2010 [March 29th, 2010]
- SA10: Commercial RLV Technology Roadmap update - April 9th, 2010 [April 9th, 2010]
- An evolving Armadillo - April 11th, 2010 [April 11th, 2010]