Saturns rings and two moons. Image credit: NASA/JPL-Caltech/Space Science Institute
A stunning image of Saturn’s rings. There are two moons in this image too, the larger of the two is obvious and is Epimetheus and the other is Daphnis.
Daphnis is a wee moon being only 8 km / 5 mi. and is very difficult to see unless you click the image to get the larger view. Look just to the right of center and in the rings just to the inside of the (Keeler) gap.
More about Saturn.
Before you read the NASA supplied caption below, I wanted to let you know there are TWO different launches today and they are only a short time apart from each other:
1. The Progress 53 cargo ship is scheduled to launch from the Baikonur Cosmodrome in Kazakhstan at 20:53 UTC (15:53 EST) The coverage should be here: http://www.nasa.gov/multimedia/nasatv/ustream/ Update: Launched,
2. A SpaceX launch is scheduled for 22:45 UTC (17:45 EST). The flight will put the SES-8 communications into a geostationary orbit from Cape Canaveral Florida USA. Coverage: http://www.spacex.com/webcast/ Update: A delay due to an issue, next attempt not before Thursday. The delay came around T minus 3 minutes 40 seconds. I could not get back to the time and a news release with more info is still in the works.
Here’s the caption from NASA (link goes to much larger versions of the image):
Amidst and Beyond the Rings
While the moon Epimetheus passes by, beyond the edge of Saturn’s main rings, the tiny moon Daphnis carries on its orbit within the Keeler gap of the A ring. Although quite different in size, both moons create waves in the rings thanks to their gravitational influences.
Cassini looks at Saturn’s ring plane. Image credit: NASA/JPL-Caltech/Space Science Institute
A rather unique look at the ring-plane of Saturn. It appears we are looking at the F-ring to the right then the wide gap called the Roche Division. The light colored part is the A-ring with it’s Keeler
Gap. Keeler Gap is home to the moon Daphnis and the Cassini’s camera was pointed at Daphnis in this image. I cannot see the moon, however I can see the ripples in the ring caused by the moons gravity as it goes around. Look on the other side of the narrow Keeler Gap and you will notice a “ragged” look, those are the ripples.
The leftmost gap, is the Encke gap.
The Keeler gap looks pretty narrow and it is, being only 42 km (26 miles) across and little Daphnis keeps things in an orderly state, other then the ripples or waves it creates as it zips by. Zips is a good description too, Daphnis makes a complete orbit in about 14 hours!.
Daphis is one of the more recent discoveries and was made by Cassini in 2005.
Mean radius: 3.8 km
Orbit radius: 136,505 km
Mass: 7.7 (+/-1.5) x 1013 kg
More about Saturn here.
Atmosphere of Saturn. Image Credit: NASA/JPL/Space Science Institute
Here is one of the latest Cassini images of Saturn. The image has pretty nice detail of the atmospheric features of the planet. You can see the polar vortex, the question is which one. The image caption was no help, just saying the camera was pointed at Anthe.
Anthe is a very tiny moon of Saturn, only about 1km in diameter and I’m not sure it is even in frame, Anthes has a semi-major axis of 197,700 km (122,845 mi) and was discovered in 2007 by the Cassini spacecraft.
Enceladus in “Saturnshine” by Cassini. Credit: NASA/JPL-Caltech/Space Science Institute
Here’s a picture of Enceladus from Cassini. The image was taken from a distance of 832,000 km (517,000 miles). The Sun and the camera are on opposite sides of the moon. The light provided to be able to see the moon and the now famous jets of water is “Saturnshine”, light reflected off Saturn.
You might have seen the news of Curiosity finding water on Mars. The soil sample contained two percent water. This is the first direct measurement as far as I know. There have been estimates of soil water detected by the HEND instrument on the Mars Odyssey. I managed to find the reference. Further findings will be very interesting, I’d look in one of the “gullies”, then again I’d be doing all sorts of things that might be fun for me but not for the mission.
Two percent is quite a lot I would think considering. Seems like there are a few variables too, like soil particle size. I’m assuming, and I say that because I don’t know nor have I been able to find out for sure, is this hygroscopic water (i.e. beyond capillary water)? I would think it would sublimate when exposed, continuing to look at that. Here’s the story. If anybody knows leave a comment.
There will be an attempt a docking tomorrow morning (Sunday, 29 Sept.). Coverage starts at 08:30 UTC (04:30 EDT).
I’ll put a video link here before hand.
Capture was successful. Nice and smooth as far as I could see. I noted about a four second delay between the streamed version and the television. Had a little bit of a time getting the right feed and then my computer decided to spaz out for a few minutes. Not a disease or anything but ever since a couple updates ago, we seem to have these little “fits”. LOL.
Cygnus is now attached!
There will be yet another launch tomorrow too. Space X is scheduled to launch the Falcon 9 with Canadian research satellite (and the Canadian Space Agency) and MDA Corp.
The launch window opens at 16:00 UTC. I’ll have more on that launch tomorrow morning.
Mini-jet in Saturn F ring, click for a zoomed in version. Credit: NASA/JPL-Caltech/Space Science Institute
Here’s a Cassini image of a “mini-jet” in the F ring of Saturn. The mini-jets are thought to be caused by low-speed collisions of material in the F ring and this causes dusty material from the ring.
The mini-jets are sometimes called exotic trails (actually what I’ve always called them), to learn more about them have a look here.
This image is from the “dark side” of the rings, that is below the ring plane by about 48 degrees from a distance of about 1.4 million km (841,000 miles) on June 20, 2013.
Here’s a link to the original image at the Cassini page at JPL.
See the newly launched Cygnus Spacecraft in flight:
Do you want to see the Cygnus spacecraft in flight? You can go to Heaven’s Above PLUS(!) you can see if you will be able to observe the Juno spacecraft flyby of Earth on its way to Jupiter and of course the ISS sightings and other spacecraft.
For those who downloaded Stellarium from a few posts back you can set that up for the appropriate time and really narrow down where to look. I’ve been doing that lately with the morning passes of the ISS and it works very well.
BTW: You will need to configure Heaven’s Above. It’s easy and safe, I’ve been registered for nearly 10 years and NEVER got any unwanted email, hmmm, to be honest no email at all. So don’t worry about such things.
Cassini’s look at Saturn and an arc of the rings. Image NASA/JPL-Caltech/Space Science Institute
It seems like its been a while since I put a Cassini image up and this one is very nice. The image was taken from a distance of 1.1 million km (657,000 miles) using the wide-angle camera in the near-infrared light.
It almost seem like the rings have a dish shape to them.
See the full image and caption at the JPL Photojournal page Arc Across the Heavens.
Tomorrow there is a scheduled launch of the Orbital Sciences Corp. Antares rocket and Cygnus spacecraft on a demonstration mission to the ISS.
The launch was delayed due to weather concerns holding up the roll-out and a technical communications issue Friday. A look at the expected weather conditions on Wednesday shows no concerns, nice and sunny with temperatures around 22 C (72 F).
Launch is set for 14:50 to 15:05 UTC / 10:50 to 11:05 EDT.
We will have more on the launch and a link to the live shot tomorrow morning. Hope you can make it!
A ‘collar’ on Titan. Credit: NASA/JPL-Caltech/Space Science Institute
I can remember watching these images come in. I was watching on slow scan television “Live” via ham radio and I believe Goddard was the source of the transmission. The transmissions were terribly exciting. I even have the same scan converter. Fun times.
Titan’s polar collar — previously seen by Voyager 2 and the Hubble Space Telescope — has now been observed by the Cassini spacecraft, seen here in ultraviolet light. The collar is believed to be seasonal in nature. Researchers are still studying its cause and evolution.
This view looks toward the Saturn-facing hemisphere of Titan. North on Titan is up and rotated 32 degrees to the right. The image was taken with the Cassini spacecraft narrow-angle camera on April 13, 2013 using a spectral filter sensitive to wavelengths of ultraviolet light centered at 338 nanometers.
The view was acquired at a distance of approximately 1.1 million miles (1.8 million kilometers) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 4 degrees. Image scale is 7 miles (11 kilometers) per pixel.
Here is Titan from 2.3 million km (1.4 million miles) by the Voyager 2 spacecraft on 23 August 1981. Image: NASA
A nice Cassini view of the moons Mimas and Pandora across the rings of Saturn. Image Credit: NASA/JPL-Caltech/Space Science Institute
The Cassini spacecraft took this image of the two moon Mimas and Pandora with the rings of Saturn in the foreground.
Mimas is the larger of the two and the crater Herschel is plainly visible. If you think Herschel is large you would be right, Mimas is 396 km (246 miles) across and Hershel spans 130 km (81 miles) nearly 33 percent, the crater is also about 10 km (6 miles) deep.
Mimas has another distinction: as far as I know and probably owing to its icy nature, Mimas is the smallest object known to be in hydrostatic equlibrium. Briefly stated another way it is the smallest object able to use its own gravity to pull itself into a spherical shape. A note here, the composition means a lot becuase the largest object known NOT to be in hydrostatic equlibrium is the sort of oblong asteroid Pallas at 532 km, but keep in mind it is made of rock to a large degree.
The smaller moon in the picture is Pandora, which really does look potato shaped when paired with Mimas. Pandora is roughly 114 km x 84 km x 62 km (71 miles x 52 miles x 39 miles).
Source: Two Moons Passing in the Night
Cassini shows Saturn is controlling the spray from the moon Enceladus. Click to see the moon pictures enlarged. Credit: NASA/JPL-Caltech/University of Arizona/Cornell/SSI
Oddly enough I was refreshing my memory about tidal action between solar system bodies a few weeks ago so this is very timely.
After seeing this Cassini news it occurs to me in the case of Enceladus, what we see is a pump, a really-really big pump. How cool is that!
I’ll let the Cassini press release explain:
This set of images from NASA’s Cassini mission shows how the gravitational pull of Saturn affects the amount of spray coming from jets at the active moon Enceladus. Enceladus has the most spray when it is farthest away from Saturn in its orbit (inset image on the left) and the least spray when it is closest to Saturn (inset image on the right).
Water ice and organic particles gush out of fissures known as “tiger stripes” at Enceladus’ south pole. Scientists think the fissures are squeezed shut when the moon is feeling the greatest force of Saturn’s gravity. They theorize the reduction of that gravity allows the fissures to open and release the spray. Enceladus’ orbit is slightly closer to Saturn on one side than the other. A simplified version of that orbit is shown as a white oval.
Earth as seen by the Cassini spacecraft. Image Credit: NASA/JPL-Caltech/Space Science Institute
I am impressed!! Cassini returned a great picture and the mission team did a fabulous job processing the image. I mean look at it, even from 898 million miles the Earth can be easily recognized.
You know you want a desktop of this, I have mine already and it looks great.
The moon can be seen in this image but not easily or at least for me. Read the story and see all the larger versions including a Earth moon image and get your desktop version.