Martian Dust Devils


The image above shows three dust devils in the Ganges Chasma (Valles Marineris) on Mars.  It was taken by the HiRISE camera on board the Mars Reconnaissance orbiter.    There were actually eight dust devils captured in an image you can see here from NASA.

Here is most of the caption released with the image:

Both of these factors help warm the surface and generate convection in the air above. The surface is streaked with the faint tracks of earlier dust devils. A pair of dust devils appears together at top right, spaced only 250 meters apart. These two have quite different morphologies. The bigger one (on the right) is about 100 meters in diameter and is shaped like a doughnut with a hole in the middle. Its smaller companion is more compact and plume-like, but it too has a small hole in the center, where the air pressure is lowest. It may be that the smaller dust devil is younger than the larger one. A row of four dust devils are in the middle of the color strip, separated by about 900 meters from one another.

This image might answer some interesting questions about the behavior of dust devils. Dust devils are theoretically expected to migrate uphill on a sloping surface, or migrate downwind when there is a breeze. Where they are found close together in pairs, they are expected to rotate in opposite directions. HiRISE color observations can be used to determine the direction of rotation and-for fast moving dust devils-the direction of their travel. This is because the different color observations (infrared, red, and blue) are taken at slightly different times. The differences between the earliest color observation and the last tell us about the changes that took place during that time interval.

All this requires careful analysis, but if these dust devils are moving fast enough, and spaced closely enough, these here might display some interesting “social dynamics,” possibly marching together and rotating in alternating directions.

NASA/JPL-Caltech/Univ. of Arizona

The Aurora

I looked for the aurora in the evening, I could tell it was there but the (busier and normal) traffic was not helping the situation and then the moon was washing things out in the very early morning.


Spacewalk Tomorrow


This is the second of a pair of spacewalks (the first was 28 Oct).  The spacewalks will facilitate station upgrades and maintenance tasks, including installing a thermal cover on the Alpha Magnetic Spectrometer, which is a state-of-the-art particle physics detector that has been attached to the station since 2011.

The spacewalk on Nov. 6 is the 33rd U.S. spacewalk, and will attempt to restore the port truss ammonia cooling system to its original configuration. A spacewalk conducted in November 2012 tried to isolate a leak in the truss’ cooling supply, but the leak was subsequently traced to a different component. NASA TV coverage will begin at 5:45 a.m., with the spacewalk scheduled to begin at 7:10 a.m.

There will be a video link posted here before the spacewalk.

Halloween Asteroid Update


This updated set of images of the Halloween asteroid released yesterday.  Very nice detail for radar images.  Be sure to click the image above for a larger version.

Asteroid 2015 TB145 is depicted in eight individual radar images collected on Oct. 31, 2015 between 5:55 a.m. PDT (8:55 a.m. EDT) and 6:08 a.m. PDT (9:08 a.m. EDT). At the time the radar images were taken, the asteroid was between 440,000 miles (710,000 kilometers) and about 430,000 miles (690,000 kilometers) distant. Asteroid 2015 TB145 safely flew past Earth on Oct. 31, at 10:00 a.m. PDT (1 p.m. EDT) at about 1.3 lunar distances (300,000 miles, 480,000 kilometers).

To obtain the radar images, the scientists used the 230-foot (70-meter) DSS-14 antenna at Goldstone, California, to transmit high power microwaves toward the asteroid . The signal bounced of the asteroid, and their radar echoes  were received by the National Radio Astronomy Observatory’s 100-meter (330-foot) Green Bank Telescope in West Virginia. The images achieve a spatial resolution of about 13 feet (4 meters) per pixel.

Image Credit: NASA/JPL-Caltech/GSSR/NRAO/AUI/NSF

Stellar Shrapnel

Veil Nebula Supernova Remnant

Beautiful image of the Veil Nebula. I always have a hard time trying to take a decent image of the Veil,

Hubble description:
Not long before the dawn of recorded human history, our distant ancestors would have witnessed what appeared to be a bright new star briefly blazing in the northern sky, rivaling the glow of our moon. In fact, it was the titanic detonation of a bloated star much more massive than our sun. Now, thousands of years later, the expanding remnant of that blast can be seen as the Cygnus Loop, a donut-shaped nebula that is six times the apparent diameter of the full moon. The Hubble Space Telescope was used to zoom into a small portion of that remnant, called the Veil Nebula. Hubble resolves tangled rope-like filaments of glowing gases. Supernovae enrich space with heavier elements used in the formation of future stars and planets — and possibly life.

Visit Hubblesite for larger images.

M57 – The Ring Nebula


From — Charles Messier’s Catalog of Nebulae and Star Clusters:
18h 45m 21s (281d 20′ 08″) +32d 46′ 03″(January 31, 1779) `A cluster of light between Gamma & Beta Lyrae, discovered when looking for the Comet of 1779, which has passed it very close: it seems that this patch of light, which is round, must be composed of very small stars: with the best telescopes it is impossible to distinguish them; there stays only a suspicion that they are there. M. Messier reported this patch of light on the Chart of the Comet of 1779. M. Darquier, at Toulouse, discovered it when observing the same comet, and he reports: “Nebula between gamma and beta Lyrae; it is very dull, but perfectly outlined; it is as large as Jupiter & resembles a planet which is fading”.’

The Ring Nebula or M57 is located 2,300 light-years / 0.7 kpc away in the constellation Lyra.  This image was taken by the WFPC2 camera onboard the Hubble Space Telescope in 1998.

More about the Ring Nebula from SEDS.

Image credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)



Click for a larger version.

NASA’s description:
New Horizons scientists have discovered a striking contrast between one of the fresh craters on Pluto’s largest moon Charon and a neighboring crater dotting the moon’s Pluto-facing hemisphere. The crater, informally named Organa, caught scientists’ attention as they were studying New Horizons’ highest-resolution infrared compositional scan of Charon. Organa and portions of the surrounding material ejected from it show infrared absorption at wavelengths of about 2.2 microns, indicating that the crater is rich in frozen ammonia — and, from what scientists have seen so far, unique on Pluto’s largest moon. The infrared spectrum of nearby Skywalker crater, for example, is similar to the rest of Charon’s craters and surface, with features dominated by ordinary water ice.

This composite image is based on observations from the New Horizons Ralph/LEISA instrument made at 10:25 UT (6:25 a.m. EDT) on July 14, 2015, when New Horizons was 50,000 miles (81,000 kilometers) from Charon. The spatial resolution is 3 miles (5 kilometers) per pixel. The LEISA data were downlinked Oct. 1-4, 2015, and processed into a map of Charon’s 2.2 micron ammonia-ice absorption band. Long Range Reconnaissance Imager (LORRI) panchromatic images used as the background in this composite were taken about 8:33 UT (4:33 a.m. EDT) July 14 at a resolution of 0.6 miles (0.9 kilometers) per pixel and downlinked Oct. 5-6. The ammonia absorption map from LEISA is shown in green on the LORRI image. The region covered by the yellow box is 174 miles across (280 kilometers).

Image: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

Enceladus Flyby

On 28 October the Cassini did a flyby of the Saturn moon Enceladus. It was the deepest flyby into the plume of the moon since it was discovered. Cassini was to fly as close as 48 km / 30 miles from the surface.


A view of Enceladus prior to the flyby.  There looks to be a small moon near the rings.

The flyby had three things in mind:
1. Confirm presence of molecular hydrogen (H2)
2. Better understand the chemistry of material in the plume
3. Determine the nature of the plume sources

Cassini was not designed to sample cryovolcanism, however it does have very powerful suite of scientific instruments making such a maneuver possible.

Below we have a view of the surface from just 124 km / 77 miles with a resolution of 15 meters / 49 ft per pixel:


Original caption:
During its closest ever dive past the active south polar region of Saturn’s moon Enceladus, NASA’s Cassini spacecraft quickly shuttered its imaging cameras to capture glimpses of the fast moving terrain below. This view has been processed to remove slight smearing present in the original, unprocessed image that was caused by the spacecraft’s fast motion.

This view is centered on terrain at 57 degrees south latitude, 324 degrees west longitude. The image was taken in visible light with the Cassini spacecraft wide-angle camera on Oct. 28, 2015.

Images: NASA/JPL-Caltech/Space Science Institute