Neptune’s Clouds

Voyager's look at clouds on Neptune.  Credit: NASA Jet Propulsion Laboratory / NASA Planetary Photojournal

Voyager’s look at clouds on Neptune. Credit: NASA Jet Propulsion Laboratory / NASA Planetary Photojournal

The bit of an interlude in the ESA’s Comet watch blog is a good time to look at some of Voyager 2’s images of Neptune. This is one of my favorites. I don’t really know if there is more than coincidence that the New Horizon’s spacecraft crossed the Neptune orbit 29 years almost to the day after Voyager started its Neptune encounter.

There is a lot of comparisons being drawn between the New Horizon’s and Voyager missions. Hey I’m on board with it. If I had my way there would be a “Le Verrier” or “Galle” spacecraft, a Neptune analog of the Cassini spacecraft in orbit right now.

In case you were wondering what was going on with Rosetta, everything is fine. Mission managers are looking at images from as close as 50 km trying to select the best landing spot. New images will be posted shortly.

This image comes from NASA’s Solar System Exploration (and Planetary Photojournal) site:

This Voyager 2 high resolution color image, taken 2 hours before closest approach, provides obvious evidence of vertical relief in Neptune’s bright cloud streaks.

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20 Years Ago


20 years? Already? Hard to believe but true.

Comet Shoemaker-Levy 9 impacted the planet Jupiter 16 July 1994. The comet broke up under the influence of the gravitational pull of the planet during a close pass in July 1992 (was within the Roche limit) and impacted two years later.

The image above is one of many images you can find at our Comet Shoemaker-Levy 9 page. Be sure to visit the links for the legendary Eugene Shoemaker too.

Image credit: NASA

Ring around the Asteroid

Until now we thought only big things had rings, really big things like Saturn and Jupiter. Turns out rings can occur around much smaller objects, like the asteroid Chariklo.

Chariklo or more formally 10199 Chariklo is a minor planet orbiting beyond Saturn, in fact its orbit is such it gets out to the orbit of Uranus.

Chariklo is only about 248 to 258 km / 154 to 160 miles in diameter (plus or minus 18 km), it has not one but two ring named Oiapoque and Chuí. It is almost unbelievable the rings could be detected, especially since Charilko was found only relatively recently, in February of 1997 by James Scotti of Spacewatch.

NOTE: Not sure what is going on with the Space X launch scheduled for 20:58 UTC (4:58 EDT). The last I have heard is there is an 80 percent chance of launch (from KSC) due to weather. There will be a press conference in a little while, I hope to be back with more news then.

Space X update:  

Sounds like there are adding a “late load” to the spacecraft right now and are attempting to have things ready tomorrow.

Space X is go for launch.


The Travels of the Torch

I’m watching some of the Olympic coverage this morning. Got to thinking about how much work the athletes have put into for the honor of representing their respective countries. The dedication and ability is simply amazing.

The whole event is a great spectacle, even the travels of the torch were over the top.


Parting Shot from Voyager 2

Neptune and Triton 3 days after flyby. Triton is smaller crescent and is closer to viewer.

Neptune and Triton 3 days after flyby. Triton is smaller crescent and is the closer of the two. Credit: NASA

Here’s a parting shot from the Voyager 2 spacecraft of the planet Neptune and its large moon Triton taken shortly after the historic flyby of August 25, 1989.

Triton is an odd moon. Inclined 23 degrees from the plane of Neptunes equator and orbiting the planet in the opposite direction of the planet’s rotation would seem to indicate Triton was captured by Neptune’s gravity and not formed with the planet. Many moons in the solar system are retrograde (mostly around Jupiter) but Triton is by far the largest, at 2,706 km, it’s not much smaller than our moon.

Triton is very cold, only 38 Kelvin or – 235 C (-391 F). You’d think it would be frozen solid, yet the moon has a rather “young” surface. It is thought when the moon was captured it not unxepectedly had an eliptical orbit which became circular over time thanks to tidal forces from Neptune. The flexing and streching of the moon created heat in the interior of the moon and led to volcanic activity. Volcanic activity in this case would involve ices and not lava.

Read more about Neptune here and Triton here.