One for the science geeks

[Wobbly]

NASA world wind - another globe mapping application kind of like google earth, though the vast majority of data is just satellite and not aerial photography. However, it does have other planets based on NASA photography and mapping, and the ability to add lots of other mapping plugins to it. Also lets you add lighting sources and shading effects, has decent relief definition so you can rotate and view things with reasonable simulation of the topography etc etc. Pretty neat.

http://www.worldwindcentral.com

[Wobbly]

While on the same subject, was doing a bit of reading lately on Galileo surveying mission and on the more recent cassini probe. Nasa has some good content on the web that includes probe photography and so on (check out http://saturn.jpl.nasa.gov/home/index.cfm ).

Also was interested to see that voyager 1 & 2 are still active projects and are currently still transmitting data, though voyager 2 has some issues by the looks. The pioneer probes were still transmitting data until around 2002 or so, but are now shut down. Voyager 1 has moved out of what is considered out immediate solar system and is in the heliosheath, which is the separation region before reaching the heliopause, the boundary between our solar system and the material within it and interstellar space.

Its reckoned that voyager 1 will reach the heliopause in about another 8 years, which is what is considered to be the separating boundary between out solar system and interstellar space. This is an area where our sun's solar wind isn't strong enough to push back interstellar material, which I'm guessing will mean they will be able to sample interstellar material for the first time which is pretty exciting.

Unfortunately the voyager probes begin to start shutting down around 2016 and its expected that systems will begin going off-line around 2020, which means we may not be able to work out whether the postulation about the hot hydrogen wall are true or not, or sample material from true interstellar space. But then again, these probes have lived well beyond their initial design intention.

The physics involved is pretty amazing too - given all the gravity assists that they have been able to use, voyager 1 is now travelling at its final escape velocity of approximately 17km/s relative to the sun. That's over 60,000km/h. The current trajectory of the probes isn't going anywhere near a close by star, but even if they were pointed directly at alpha centauri (our closest neighbour) they would still take over 700 years to reach it, as they are travelling at about 0.05% of the speed of light...

[MarkeeMark]

Neil you amaze me. We all have our interests and your the first person I know to talk about interstellar space and heliopause!
Good on ya mate and thanx for sharing.

[Wobbly]

Interestingly the cassini probe that is now at saturn reached some pretty phenominal speeds relative to the sun. Its max velocity RTTS was about 45km/s as it slingshotted past jupiter. That's over 160,000km/h.

Its now arc'd around and is orbit around saturn (where it will live out its life before either being parked or crashed into something) and is powered by a plutonium fuel cell and is designed to live until about 2012.

Here's an image it took of jupiter as it flew by...

http://upload.wikimedia.org/wikipedia/commons/thumb/a/ac/PIA04866_modest.jpg/422px-PIA04866_modest.jpg

[MarkeeMark]

That truely is amazing.

[Wobbly]

Dunno, I just find it incredible to think about ... we sit here thinking about 0-100 times and 300kph speeds as being impressive, yet there are man made things whizzing around that are covering speed and distance that makes that all seem so insignificant. Here's a few more pics of jupiter as well - these arent computer models or some artist drawing it up, these are pictures taken from a man made camera from a vehicle travelling at incredible speed....

http://www.jpl.nasa.gov/jupiterflyby/gallery/gl_browse/shadow_magic_browse.jpg

http://www.jpl.nasa.gov/jupiterflyby/gallery/gl_browse/PIA02821_browse.jpg

http://www.jpl.nasa.gov/jupiterflyby/gallery/gl_browse/jupganyfinal_browse.jpg

http://www.jpl.nasa.gov/jupiterflyby/gallery/gl_browse/pia02860_browse.gif

[SM93]

nice!

[Daws]

+ 1 for worldwind, I'm sure it has an offline capability that google earth does not have, It's been a year or so since I used it last so I my memory may be addled by time and beer.

If people are interested in Satellite photography check out the Blue Marble on the NASA Earth Observatory site - http://earthobservatory.nasa.gov/ sign up for the newsletter and once a week you get an update of new images.

The Blue Marble has the highest quality images of the globe available for download. going from memory I think they have a 400Mb JPEG available for download which will print well at pretty much any size you can care to imagine!

Often featured on the EO site is the Terra Modis satellite, this is particularly important to Australia as it's used for (amongst other things) early detection of ground hot-spots which may turn out to be Bushfires.

[devo]

Dunno, I just find it incredible to think about ... we sit here thinking about 0-100 times and 300kph speeds as being impressive, yet there are man made things whizzing around that are covering speed and distance that makes that all seem so insignificant. Here's a few more pics of jupiter as well - these arent computer models or some artist drawing it up, these are pictures taken from a man made camera from a vehicle travelling at incredible speed....
I'm not an astronomy nut, but I'm right there with you on the sheer enormity and scale of it all.
YouTube - The Relative Size of Stars & Planets (& Pluto ;-)
Some relative sizes.

http://nssdc.gsfc.nasa.gov/image/astro/hst_ngc4414_9925.jpg
A galaxy much like ours, made up of millions of those big-ass stars.

http://nssdc.gsfc.nasa.gov/image/astro/hst_deep_field.jpg
More than a few just like it.

YouTube - Broadcast Yourself.
A hilarious reminder that not everyone is inclined to think beyond the end of their street.

Bloody incredible what we're already doing in terms of opening up our part of the universe (I say "we", but I mean "they" :lol: ), but then to think how we haven't even barely scratched the surface.