By Adi

I have always wondered if there will ever be a day when we shall be able to control time and space. You know, fast forward things we experience, then slow them down… Zoom into our world and then zoom back out simply with a two-finger pinch? For the time being at least, such control of our everyday experience seems to be in the realms of science fiction. But I recently discovered three new web-based visualization apps that can give us a feel for how useful such control would be for scientists.

Satellite imagery lets you follow terrain changes over time.
Google Earth enters the fourth dimension.

I invite you to try out these novel ways of looking at the Earth, the planets and the stars!

These apps require Adobe Flash and seem to work best on Google Chrome.

1. Timelapse

Over the last few decades, NASA’s Landsat satellites have monitored how the human species has been altering the surface of the planet. Now clever folks at Google Earth have combined millions of snap-shots taken by multiple satellites over the years and stitched it into a time-lapse video. Check out the montage below for an insightful view of our impact on the planet.

I encourage you to visit, type in your home city and see how that region of the planet has evolved since 1984.

Click here for the view centered on Canberra, Australia (notice how a big green chunk of the Mount Stromlo forest disappears after the 2003 bush fires).

2. Dynamic Orrey

Screenshot of OrreyAn orrery is a mechanical device that illustrates the relative positions and motions of the planets and moons in the Solar System in a heliocentric model. The first orrery was produced in 1704 but this 21st century web based version allows the user to set the date, control the speed of the rotation of the Solar System. Perhaps one of the coolest features is the ability to see what the Solar System looks like in Tycho’s geocentric view!

For the space enthusiasts, I recommend setting the date in the visualization to 20 August 1977, when Voyager 2 was launched and using the rotation speed slider to follow the probe’s path across the solar system to Jupiter (’79), Saturn (’81), Uranus (’86) and Neptune (’89). Voyager’s trajectory was designed to take advantage of an unusual alignment of the planets that occurs once every 177 years!

3. Views of the Sky

For the astronomers amongst us, this visualization beautifully illustrates the difference between apparent brightness and absolute brightness of a star (luminosity). For the rest of us, checkout how stars that appear to be a part of a particular constellation in the night sky are often separated by significant distances from each other in 3D space.

view 1

How close together are the stars in your favorite constellation? One easy constellation to find is the Southern Cross and the two pointer stars (marked in the screen-shot above by the red circle)

Know of other cool visualizations? Then do let us know in the comments.