Category Archives: Dawn

NavCam View of Ceres

A very nice look at Ceres from Dawn’s NAVCAM. The bright spot in Occator Crater at the top of the image.

The Dawn spacecraft is moving to a new orbit 20,000 km / 12,400 miles above Ceres, this image was taken on 28 March 2017 at a distance of 48,300 km / 30,000 miles. Dawn should be in place by the end of the month.

From NASA:
Several familiar features can be identified: At the top, we see Occator Crater and its faculae (bright deposits identified as a mixture of sodium carbonate and other salts). Below center is the crater Urvara, and to the right of it, the larger crater Yalode (the third and second largest craters on Ceres, respectively). Large-scale faults called Samhain Catenae stretch from the Occator region toward the Yalode-Urvara region.

This map can be used to locate these and more features. (Link goes off-site, use your back button to return)



Dawn’s Look at Ceres

The Dawn spacecraft returned this very nice image of the dwarf planet Ceres. It features Occator Crater and Ahuna Mons.

Ahuna Mons is the tallest mountain on Ceres, some 4 km / 2.5 miles high, it is visible on the right limb of the planet. Occator Crater is hard to miss with the bright evaporite deposits at the crater’s center and along the floor.

According to NASA both features are relatively young, share a similar composition — different from Ceres’ average composition — and hint at recent internal activity in the dwarf planet. Cere’s is a mysterious place.

Dawn took this image during its third extended-mission science orbit (XMO3), from a distance of about 4,700 miles (7,500 kilometers) above the surface of Ceres. The image resolution is about 2,300 feet (700 meters) per pixel.


Fly Over Occator

Thanks the the Dawn spacecraft we can take a “fly-over” of Occator crater on the dwarf-planet Ceres. The bight areas are may have been produced by upwelling of salt-rich liquids after the impact that formed the crater.

The animation was produced by the German Aerospace Center (DLR). Original music by Stefan Elgner, DLR.

Video – JPL / NASA

Yalode Crater


It’s all about perspective.

Original caption:
Sunlit cliffs tower above Yalode Crater on Ceres in this shadowy perspective view. At 152 miles (260 kilometers) in diameter, Yalode is one of Ceres’ largest craters. A fissure called Nar Sulcus is seen just right of center.

Dawn took this image on Oct. 19, 2016, from its second extended-mission science orbit (XMO2), at a distance of about 920 miles (1,480 kilometers) above the surface. The image resolution is about 460 feet (140 meters) per pixel.

A different view of Yalode, taken almost exactly one year prior, can be seen by clicking the image.


Ceres in Color


Great look at Ceres, click the image to see a larger version.

This view of Ceres, produced by the German Aerospace Center in Berlin, combines images taken during Dawn’s first science orbit in 2015 using the framing camera’s red, green and blue spectral filters. The color was calculated using a reflectance spectrum, which is based on the way that Ceres reflects different wavelengths of light and the solar wavelengths that illuminate Ceres. — NASA


Occator Crater Viewed Again


The Dawn spacecraft is still orbiting the dwarf planet Ceres and delivering great results.  This view of Occator Crater was taken on 18 October 2016 and highlights the area around the bright salt exposures.

From NASA/Dawn:

This image from NASA’s Dawn spacecraft shows Occator Crater on Ceres, with its signature bright areas. Dawn scientists have found that the central bright spot, which harbors the brightest material on Ceres, contains a variety of salts. The brightest parts of these features are overexposed in this image, which had an exposure time intended to capture details in the surrounding terrain. Shorter exposures allow details within the brightest areas to be seen, as in PIA20653.

Dawn took this image on Oct. 18, 2016, from its second extended-mission science orbit (XMO2), at a distance of about 920 miles (1,480 kilometers) above the surface. The image resolution is about 460 feet (140 meters) per pixel.



What Would Giuseppe Think?


This is an image of Ceres taken by the Dawn spacecraft taken on 13 June 2016.

Great image! Funny think was my very first thought was what would Giuseppe think.

Giuseppe Piazzi discovered Ceres on 1801.

From his journal:
The light was a little faint, and of the colour of Jupiter, but similar to many others which generally are reckoned of the eighth magnitude. Therefore I had no doubt of its being any other than a fixed star. In the evening of the second I repeated my observations, and having found that it did not correspond either in time or in distance from the zenith with the former observation, I began to entertain some doubts of its accuracy. I conceived afterwards a great suspicion that it might be a new star. The evening of the third, my suspicion was converted into certainty, being assured it was not a fixed star. Nevertheless before I made it known, I waited till the evening of the fourth, when I had the satisfaction to see it had moved at the same rate as on the preceding days.

About Guuseppe Piazzi and the discovery of Ceres and more.


Carbonates in Occator Crater


Now know the bright material in Occator crater is a carbonate. We also know that carbonate is sodium carbonate.

Great news IMHO.
From Dawn:
The center of Ceres’ mysterious Occator Crater is the brightest area on the dwarf planet. The inset perspective view is overlaid with data concerning the composition of this feature: Red signifies a high abundance of carbonates, while gray indicates a low carbonate abundance.

Dawn’s visible and infrared mapping spectrometer (VIR) was used to examine the composition of the bright material in the center of Occator. Using VIR data, researchers found that the dominant constituent of this bright area is sodium carbonate, a kind of salt found on Earth in hydrothermal environments. Scientists determined that Occator represents the highest concentration of carbonate minerals ever seen outside Earth.

Mystery Spots on Ceres

A nice look at some of those mysterious white spots on Ceres. The area shown above is some of the brightest on the dwarf planet.

From the Dawn vantage point of just 385 km / 240 miles scientists believe the white material is some of salt.

Looking in the center of the image at the grooved or canyon-like features it appears the ‘salts’ are not inside at the bottom – click the image to see the larger version. The mountainous feature is completely covered including irregular terrain. So knowing what type of salt we are looking at will go a long ways towards solving the second part and larger part of the mystery: how the salts came to be where they are.

The resolution of the image is very good showing 35 meters / 120 feet per pixel. I am going out on a limb and say those canyon-like features are about 210 meters / 690 feet across.