This image from the Lunar Reconnaissance Orbiter shows a close-up of an 80-foot-wide boulder on the central peak of Gassendi Crater, a trail left behind it in the dark lunar soil. There’s even a bit of a pile-up of soil in front of it where it came to rest! Several smaller boulders on either side…
Good Vibrations
Dynamic spike-like structures along the edges of Saturn’s rings are caused by oscillations of material that mimics the behavior of our entire galaxy…in other words, Saturn’s rings are a miniature version of the Milky Way! Along the outer edge of the dense B ring Cassini mission scientists have observed ring particles rising above the ringplane…
Peak Time
A crater’s central peak casts a long shadow in this image from Cassini, taken on October 17 as the spacecraft passed by Dione at a distance of 25,000 miles. 700-mile-wide Dione is literally covered in craters, faults and gouges, a testament to the ancient age of its frozen terrain. Many larger craters – like the…
It’s (Not) the Great Pumpkin, Charlie Brown
Good grief! What a cool image this is: the Sun as photographed by Alan Friedman in hydrogen alpha light. The detail in the surface (photosphere) is simply amazing, especially considering the image was taken with a backyard telescope (albeit a very fancy backyard telescope!) Click the image to go to Alan’s page where you can…
Flare Up
I caught this image this morning on the SDO site…it shows an eruption of plasma from the Sun’s photosphere that stretches out several tens of thousands of miles…the hooked loop at the end could easily encircle the entire Earth! This image is from about 11am or so, within a couple of hours the structure had…
Like a Rolling Stone
A boulder leaves a bounding trail in the lunar dust Here’s a neat image for today: a detail of the central peak of Eratosthenes Crater, taken by the Lunar Reconnaissance Orbiter Camera (LROC), shows a trail a rolling boulder has left in the regolith (the fancy word for Moon dirt.) The boulder, located in the…
A Setting Titan
A series of 13 raw images from Cassini, taken October 18, 2010, has been looped together to create this animation showing Titan “setting” behind the nighttime limb of Saturn. Check out the refraction along Saturn’s atmosphere! Very cool. (The images are oriented so the ringplane – seen at left – is running vertically.) This is the view…
A Pair of Flares
A twisting pair of prominences erupt almost 50,000 miles above the surface of the sun in this image from SDO, taken today, October 21, 2010. This is a composite of two imaging wavelength filter images (AIA 304 and 171), combined to show surface (photosphere) detail as well as lower atmosphere (chromosphere) detail. The scale…
Stars and Stripes (and Titan!)
A color-composite RGB image of Titan, with a sliver of the rings and a scattering of stars in the background, taken by Cassini on October 18, 2010 from a distance of over 1.53 million miles. At 3,200 miles in diameter Titan is larger than the planet Mercury, boasting a complex – yet chilly – atmosphere…
Enceladus and the E Ring
This is really great…an out-of-the-box raw image from Cassini showing Enceladus jetting along inside the hazy, diffuse E-ring. The spacecraft was over 414,000 miles away from the 300-mile-wide moon when this was taken. As a bonus we get a nice scattering of background stars too! This is one of those images that would have been…
A Sphere of Ice
Here’s a wonderfully crisp portrait of Saturn’s moon Rhea, taken by Cassini on October 17, 2010 at an altitude of 24,300 miles. Illuminated on the right by sunlight, the left hemisphere is dimly lit by reflected light from Saturn. Rhea is Saturn’s second-largest moon after Titan, but at 950 miles across (compared to 3,200) Rhea is…
The Sun and the Moon
From an SDO image chosen as the Pick of the Week for October 15th, this shot is almost too cool to be real…but it is! As the New Moon passed between the Solar Dynamics Observatory and the Sun, the spacecraft in geosynchronous orbit got a view of the Moon’s silhouetted disc passing across its normally-unobstructed…
Lights in the Dark 