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All planets (and moons) have magnetic fields.

Actually, that's not true at all. Among the objects that don't generate a real, structured magnetic field, we have Venus, The Moon , Io, Europa, and Mars. Of course, *why* some planets have fields and some don't is still up in the air (rotation of the Earth's core generates our magnetic field, or so it is assumed, and yet Mercury, which almost certainly has a solid core, possesses a planetary magnetosphere).

I think the first of those images especially is much more interesting than the "flatter than a pancake" altitude reading in the original post. You can see a lot of surface detail (unfortunately in a region where we don't yet have optical imaging). Look at the left side of the 'diversity' image. Notice the large dark circular feature? Circular feature == crater on a moon like Titan. That is something that we hadn't seen in the optical images. Then notice the bright area inside the crater rim. On these radar images, bright area == roughed up surface. Notice the little squiggly white bit going down from the bright area to the center of the crater? That has got to be an erosion channel from liquid running down into the crater. Then look at the center of the crater. You see another feature with very smooth edges, shaped sort of like a peanut. Any guesses as to what that is? My guess is a pool of the liquid that ran down. Very exciting image!

I think the first of those images especially is much more interesting than the "flatter than a pancake" altitude reading in the original post. You can see a lot of surface detail (unfortunately in a region where we don't yet have optical imaging). Look at the left side of the 'diversity' image. Notice the large dark circular feature? Circular feature == crater on a moon like Titan. That is something that we hadn't seen in the optical images. Then notice the bright area inside the crater rim. On these radar images, bright area == roughed up surface. Notice the little squiggly white bit going down from the bright area to the center of the crater? That has got to be an erosion channel from liquid running down into the crater. Then look at the center of the crater. You see another feature with very smooth edges, shaped sort of like a peanut. Any guesses as to what that is? My guess is a pool of the liquid that ran down. Very exciting image!

The guys at the JPL had the same thought.

That's no space station

Also, the interesting thing about Titan is that the cloud cover which should be methane seems to be composed of something else, altogether. Particles such as ethane and even polystyrene have been suggested as possible cloud particles.

Among the recent images provided by NASA is a graph showing data from the ion and neutral mass spectrometer as Cassini sniffed Titan's upper atmosphere (far away from the cloud at the southern pole, if I understand it correctly). Some compounds have been identified by mass and labelled, such as hydrogen (2 Da), methane (16 Da) and nitrogen (28 Da).

However, I wonder what that unlabelled band at 7 Da (between hydrogen and methane) represents. What molecule could possibly have a mass of 7? I haven't taken a chemistry class since 1980, so please help me decode this. Are we seeing lithium ions or something?

As for the speculation that the clouds contain some "organic goo", didn't someone long ago suggest that the moon was made of cheese..?

right here

fascinating stuff. shows titan flat as a pancake for 100's of kilometers.

I am hoping that the radar data can provide the elevation data they lack from the visual stuff.

Looking at some of the preliminary radar data (here), there's a strip 400km long, with no more than 100 meters of height variation. That's flatter than the state of Kansas!

Read this

Extract:
The data show a variation in height of only about 150 meters (490 feet) over the 400-kilometer-long (250-mile-long) track, indicating that in this region Titan is remarkably flat.

They do know something, but not much. Take a look a the first synthetic aperture radar image and first altimetry scan of Titan's surface (there's only a variation of like 50 meters!) and compare this to the synthetic aperture radar from Magellan at Venus . For one thing there are practically no craters on the Titan radar image!!! Its a "new" surface!

They do know something, but not much. Take a look a the first synthetic aperture radar image and first altimetry scan of Titan's surface (there's only a variation of like 50 meters!) and compare this to the synthetic aperture radar from Magellan at Venus . For one thing there are practically no craters on the Titan radar image!!! Its a "new" surface!

They do know something, but not much. Take a look a the first synthetic aperture radar image and first altimetry scan of Titan's surface (there's only a variation of like 50 meters!) and compare this to the synthetic aperture radar from Magellan at Venus . For one thing there are practically no craters on the Titan radar image!!! Its a "new" surface!

"That's no moon..." is the comment for Mimas, not Titan :)

One thing I'm curious about is what effect that the Sun's activity has on climate change. There have been spacecraft studying the sun and more spacecraft studying the magnetosphere and it's interaction with the solar wind. However, it seems that we only have understanding of individual events and the immediate effects of those events. It will be really interesting when some people get a good idea of what long term effects CMEs (coronal mass ejections) and other Sun activity has on our little blue world.

NASA has a similar application. It's not as sleek as keyhole; on the other hand it's free.

--
CuTest

World Wind is here. Just be sure to deselect "Landsat 7" from the toolbar (this uses NASA servers that are out of commission) and select "USGS-1m" instead for 1m resolution for the US. For some urban areas you can get much higher resolution and color by going into the "Layer Manager" under Images->High Resolution Terrain Mapped Imagery and selecting "USGS Urban Aera Ortho-Imagery". The topo maps are cool too.

why use keyhole when NASA has a FREE and open source solution, which looks very similar WorldWind

of course it only runs on windows... Open Source.Net

it may not be as geared toward streetmaps, but I have found it useful for finding back roads and stuff.

For more refutations to your arguments, please refer to the Mars Reference Mission.

My first thought too . . . http://saturn.jpl.nasa.gov/cgi-bin/gs2.cgi?path=.. /multimedia/images/titan/images/pia-titan-1-2.jpg& type=image . . . There is a regular ring on the 'land' side too, but my instinct tells me that these are camera or image processing artefacts. The interface between the light and dark, though, looks exactly like a coastline with islands and indentations formed by wave/tide action. It could be dark terrain overlaid with ice or clouds or both. You have to be careful to understand what light and dark actually mean - I don't know what wavelengths these were taken at but if the camera is optimised to see through methane/hydrocarbon smog then that would appear darkest. If the dark part is a liquid ocean then why does the top right show up as so hazy? I'm more interested in the rings. The obvious one is associated with an indentation in the coast to its 'north'. If you go left from there, there is another one much fainter but that is associated with a diffuse 'stain' or pan of material and also has a 'coastal' feature to its north. Intriguing.

remembered to take the lens cap off...

The moat around Marvin the Martians holiday home

I was waiting for someone to make death star jokes.

your url didn't copy well so here it is again:
that's no small moon.

They've done some preliminary image processing. Here is an example. Notice the crisp boundaries in the third image. It looks just like a water (liquid) boundary. Dust or rocks rarely have such distinct boundaries of color for this much area. This adds to the hydrocarbon lake theories. This is so cool!

However, it still means that the probe may land on an oval-shaped island (matching it with the prior map), which would be a bit of a disappointment, as described above. NASA, please target the damned liquid! The probe is designed to float.

From the article -

NASA Secures Approval in 30 Days
To accelerate NASA's primary science missions in a timely manner, high-end computing experts from NASA centers around the country collaborated to build a business case that Brooks and his team could present to NASA headquarters, the U.S. Congress, the Office of Management and Budget, and the White House. "We completed the process end to end in only 30 days," Brooks said.

Wow. That's incredibly fast, IMHO.

As the article mentions, I suppose NASA owes this to the success of their 512-processor Kalpana system, in honor of the late astronaut Kalpana Chawla.

And look at this --

"In some cases, a new Altix system was in production in as little as 48 hours," said Jim Taft, task lead, Terascale Applications Group, NASA. "This is starkly different from implementations of systems not based on the SGI architecture, which can take many months to bring to a reliable state and ready for science."

w00t! That's like super-fast in terms of development time. Good job, NASA. Way to go.

And what about the other companies mentioned in the article?

In addition to Intel Itanium 2 processors, the Columbia installation features storage technology from Brocade Communications and Engenio Information Technologies, Inc., memory technology from Dataram Corporation and Micron Technology, Inc. and interconnect technology from Voltaire.

I've not heard of any of them other than Voltaire - are they well known in this area, or are they defense/NASA contractors of some kind?

This is cool. It is a map pointing out where the lander is targeted. The map was made from prior flybys and also shows where today's mission is to image.

If the dark stuff really is liquid goop, as some speculate, I wish they would target a little to the north to land right in the stuff and float. I would much rather see images from floating on a lake of goop than yet more rocks. We got enough of rocks from Mars, Venus, the moon, and Eros. Time for liguid landings. Please NASA, retarget for the sake of Goop!

Ermm, which NASA are we talking about again?

National Aeronautics and Space Administration
New Advanced Search Agent

Why does the contrast look different between images?

The camera measures light from an object at each point in an image and assigns it a number from zero to 4095 depending on its brightness. Sometimes the scientist can't afford to send this amount of data for each pixel because of the amount of storage it takes. The camera has the ability to convert this range of values to those from zero to 255. The camera does this according to a preset table of values designed by the scientists. This table devotes many of the 256 levels for less bright things and less levels for brighter pixels. Part of calibrating an image on the ground is to reverse this table and get back pixels in the range of zero to 4095. Because you're looking at the raw data, images sent back in this mode will have dimmer things look brighter compared to the brighter parts of the image than in images not in this mode.

Why does the image look bizarre/psychedelic?

As in the previous question, the other way the camera can send back less data (by sending pixels with values from zero to 255 instead of zero to 4095) is to send back only the lower binary digits of the number. This is like having a list of amounts of money and only recording the amount of cents for each one and assigning the brightness in an image to the amount of leftover cents. Pixels with brightness values just under 255, like amounts just under a dollar, will appear almost white, while pixel values just over 255, like amounts just over a dollar with not many cents, will appear dark. The ideal use of this mode is for image scenes that are dark with almost all of the pixel values less than 255. If the scene is simple with gradual increases in brightness, then even if the original values get over 255 and go dark again, the scientists can figure out what the real value was. If the scene is very complicated or the original values are much brighter than 255, the image can have many bright and dark transitions with strange contours. In this case, the image will look very bizarre but not have much scientific value.

In a moon eclipse, the earth's shadow is cast *on the moon*, so no matter where you are, if you see the moon, you'll see a "total" eclipse. You may not see the event it in its entirelly because the moon will either rise already eclipsed or will set before the show is over.

With a sun eclipse, the moon's shadow is cast on earth, and since it's a tiny (in proportions) shadow, only those places along the path of the shadow experience an eclipse.

This image helps how the places on earth that will have the moon above the horizon during the time of the eclipse:

http://sunearth.gsfc.nasa.gov/eclipse/LEmono/TLE20 04Oct28/image/TLE2004Oct-Map1.GIF

I'll see it all, and plan to dust-off the scope and camera for it :)

Solars are far more exciting. I've only witnessed a very-nearly-but-obviously-not-total eclipse, and that's because my parents didn't want to shell out the money to fly to the Big Island back in 1991 (grr!)

Anyways, This site has links to images where they show the path of the eclipse on the world map. Kinda nice.

Of course, NASA's is far more comprehensive, but it doesn't show which individual cites are blessed by such eclipses.

This is the kind of FUD that holds back nuclear rockets as a useful technology. The same campaign was executed against Cassini before it went up. Here is the official risk assessment from the Environmental Impact Statement from NASA for Cassini:

Since the material
is highly insoluble, once it reaches the surface
most of it would become trapped in the
oceans or soils and not pose a health hazard.
Thus, most of the released material would not
be breathed in by people. The small amount
of released material that would be breathed in
would be distributed over much of the world.
Since the amount to be breathed in is so tiny,
the radiation dose that a person would be expected
to receive is less than one millirem
total over 50 years. This small radiation dose
is indistinguishable when compared to the
15,000 millirem dose an average person will
receive (over that same 50 year period) from
natural background radiation.
NASA Cassini Safety Page

Now granted this is a different technology, but the amount of fissile is comparable. The risk should be no greater.

Oh yes, very safe, and don't worry when it does THIS in the upper atmosphere during launch. Everyone knows plutonium dust is perfectly healthy in really small quantities right? This is the fundemental problem with launching such engines into space - you're placing extremely toxic materials on top of a potential bomb. And what's the upside? This new engine only doubles the efficiency of a chemical reactor. I doubt that the result justifies the risk.

There already was a spacecraft/satelitte that had a nuclear device in that "blew up" in space. The only thing that remained was the nuclear material, still perfectly stored in it's container. I'm sorry for not having a source to back to this up, but I'm at work. Here's a ton of info about this stuff.

We did that in 1977

It also doesn't take into account that Bush has now added a massive project onto NASA's plate (Mars mission) without (AFAICT) providing adequate extra funding.

I guess you have never heard of Sputnik? http://www.hq.nasa.gov/office/pao/History/sputnik/

Flyby, yes; Huygens, no, not until December

From the official mission fact-sheet: "On December 25, 2004, Cassini will release the European-built Huygens probe toward Titan. On January 14, 2005, the 2.7-meter-diameter (8.9-foot) Huygens will enter Titan's atmosphere, deploy its parachutes and begin its scientific observations during a descent of up to two and a half hours through that moon's dense atmosphere." (see also here and here)

If you're really "on the outreach team" it sounds like you need a serious clue.

Flyby, yes; Huygens, no, not until December

From the official mission fact-sheet: "On December 25, 2004, Cassini will release the European-built Huygens probe toward Titan. On January 14, 2005, the 2.7-meter-diameter (8.9-foot) Huygens will enter Titan's atmosphere, deploy its parachutes and begin its scientific observations during a descent of up to two and a half hours through that moon's dense atmosphere." (see also here and here)

If you're really "on the outreach team" it sounds like you need a serious clue.

Flyby, yes; Huygens, no, not until December

From the official mission fact-sheet: "On December 25, 2004, Cassini will release the European-built Huygens probe toward Titan. On January 14, 2005, the 2.7-meter-diameter (8.9-foot) Huygens will enter Titan's atmosphere, deploy its parachutes and begin its scientific observations during a descent of up to two and a half hours through that moon's dense atmosphere." (see also here and here)

If you're really "on the outreach team" it sounds like you need a serious clue.

I took a look at some of the artist impressions of Titan and the probe coming down.

http://saturn.jpl.nasa.gov/multimedia/images/artwo rk/index.cfm

At first I wondered if daylight would be that bright on Titan. That made me study the way light is depicted.

If you study the light source in several of the artistic renderings, the light striking Saturn in the background has nothing to do with the light on the surface of Titan. One image (Probe over Titan) shows Saturn getting light from a direction low on Titan's horizon, and yet there seems to be a bright halo around a dark cloud overhead, as if the sun were behind it.

I like the fantasy aspect of this, but I'm afraid we are going to be in for a big let-down when the real images arrive. I'd say that part of the interest in Titan is not science, but pure wonder lust.

Simply put, you can't have your cake and eat it too. Have you taken a look at the number of instrument packages on Cassini and Huygens? It's HUGE. You get what you pay for. Especially in terms of reliability, if you're sending a probe on an 8 year journey you kinda want to be absolutely certain it works when you get there. Double redundancy on everything and money for insane amounts of testing does that for you. As for the one megapixel thing. This misconception has been debunked many times before. Imaging spacecraft don't keep up with the latest best buy "5 megapixels for under 300$!!" race because it's irrelevant. It's the optics that matter and the more pixels you have the more data you have to transmit back to Earth per image, therefore the higher the bandwidth and the bigger the radio transmitting dish (higher gain) has to be, increasing weight and onbaord propellant requirments...see where I'm going with this? That's right, nuclear propulsion. Because if you want to do these things you need POWER to do them and an onboard nuclear reactor does that for you.

There will be a Titan flyby on Tuesday Oct, 26. Huygens will be released, and the first good images of Titan will start coming in Tuesday evening. Nasa will have special coverage. You can join #cassini on irc.freenode.net and join in the discussion. Tommorrow promises to be great fun. We invite everyone to join in on irc and party like its 1999.

The probe detaches from Cassini on Christmas for its atmospheric entry on 14 January 2005.

Interesting link for the various Nasa staff personal sites.

...since they had to compensate for a telecommunications problem. Read more here.

Titan may offer the first chance for a terrifying symphony of alien thunder.

Alien thunder?.........hrmmmmm......new, name......for a band? Yeah, that's it.

On a more serious note, here is the link to the Cassini-Huygens main page complete with a tital flyby schedule, a flyby mission description, photo essay including some amazing images of the rings of Saturn, Titan and more.

Heh heh. Check out the contrived acronyms on that page. "Growth Apparatus for the Regenerative Development of Edible Nourishment (GARDEN)"

Since NASA is getting a budget increase this year...
...do you mean NASA's relevance is actually increasing?

i couldn't find anything on pressure thresholds, but there is an article talking about how turgor pressure effects plant growth. turgor is a biology term that princeton defines better than i do. i'd imagine that the turgor pressure corresponds to atmospheric pressure in slightly different ratios species-to-species... The article also talks about yield threshold, which i think is just the output of good crop. here is more info on what plants NASA wants to grow for their astronauts ( wheat, rice, lettuce, cabbage, soy, potatoes, and others ) and some issues that they are facing ( one article mentions nuts and fruits are difficult ). too bad NASA is really buries their information...

i couldn't find anything on pressure thresholds, but there is an article talking about how turgor pressure effects plant growth. turgor is a biology term that princeton defines better than i do. i'd imagine that the turgor pressure corresponds to atmospheric pressure in slightly different ratios species-to-species... The article also talks about yield threshold, which i think is just the output of good crop. here is more info on what plants NASA wants to grow for their astronauts ( wheat, rice, lettuce, cabbage, soy, potatoes, and others ) and some issues that they are facing ( one article mentions nuts and fruits are difficult ). too bad NASA is really buries their information...

Plants grow well in mars soil, even better than earth soil. It's the atmosphere's lack of 02 that's the problem, not the soil.

Just Google it and you'll find lots of sources.

I'm also not sure how well plants will grow when they're frozen or blasted with UV Rays.

In fact Werner von Braun took some interest in the Indian space programme, in the 60s.

India's first satellite was launched 30 years ago, called Aryabhata-I named after the 6th century Indian mathematician, Aryabhata.

Also, the launching station at Thumba is right on the Magnetic Equator. A story covering this can be seen here. Also,

A map of the world's space centers is available.