Eastern horizon as seen from Adeliade at 6:57 am ACST on July 20. To wave at Saturn, go outside, face east, turn a little south and … look down at your feet.
Don't forget, on Saturday July 20, at 7:27 am AEST, 6:57 am ACST and 5:27 an AWST, (that’s July 19, 21:27 UT), the space probe Cassini will look back to Earth and take a picture of our planet.
Of course, Saturn is well below the horizon from Australia. But by getting out there and participating, you will have taken part in one of only 3 of portraits of Earth taken from a spacecraft in the outer solar system.
And besides NASA needs more photos of crazy Aussies waving at the ground. Don't forget to post your images to them for their Flickr account or Facebook page.
You can find out more at NASA’s photobomb site, there are community events at “The Day The Earth Smiled” and a live webcast of Saturn while Cassini snaps us at the Virtual Telescope.
The Australian ABC Online has a good report of this event, as well as a photo-gallery of portraits of Earth from space.
And wouldn’t you know it, the MESSENGER spacecraft at Mercury is getting in on the act! While searching for possible Mercurian Moons, Messenger will look back towards Earth and snap it’s (very small) portrait.
The times MESSENGER will be photographing Earth are 11:49, 12:38 and 13:41 UT, this translates out into 21:49, 22:38 and 23:41 AEST on the evening of both the 19th and the 20th here in Australia (subtract half a hour for central states and two hours for WA).
Again, Mercury will be well below the horizon in Australia when this happens. Follow exactly the same steps as looking for Saturn above (although this time it will be at a decent hour in the evening).