Redshift Blueshift Animation

You can watch this video at UHD (4K) filling your screen by clicking the expand button. Brand new animation of the increase in frequency observed in waves emitted from an approaching source (or conversely a decrease in frequency in waves emitted from a receding source). Happens in sound waves (e.g. a siren of an approaching emergency vehicle or the change in pitch of a passing car engine) and in light waves (the red Doppler shift of a receding star or the blue Doppler shift of an approaching star).

This animation uses a ball as the wave source. As the ball moves from left to right it emits wave-fronts that continue to radiate out from their position of origin. The ball moves on and creates a new point of origin for the next wavefront and so on. In this way, the waves bunch together at the front of the ball and spread out behind. Similar to a jet plane approaching the speed of sound and radiating sound waves. In the case of light waves then the higher frequency at the front yields a bluer light (blue shift), while behind the light source (e.g. a star) the light is stretched out, lengthening the frequency, creating a redshift. Available to licence.

Bob Shaw, Science Fiction Writer

I discovered Bob Shaw after picking up an ageing paperback of The Two Timers. I was looking for something to read late one night and I came across the yellowed book hidden in a bookcase. I'd always hoped to discover something magnificent, and this was it. It was like finding a hidden room in my own house. Two nights ago, I finished Night Walk, and before that, Dagger of the Mind. Plus a couple of short story collections. They're slightly dated but dated to that nostalgic time when I was growing up. It's like time travel. The descriptions are terse and original, with an underlying sly wit and wordplay. And the books are crammed with brilliant ideas. Who can ask for more? Tonight I'll travel back in time and into the future since I just bought The Palace of Eternity.

Water on the Moon

With all this excitement going on about water ice on the moon, and a new lunar age dawning, sit back and watch this re-vamped animation showing the phases of the moon:

Simplified, mechanical-style animation of the Moon orbiting the Earth showing the phases of the moon.

THE MOON varies in appearance throughout the lunar month as it orbits the Earth. This animation shows in a very simplified form how the sunlight (coming from lower right) shines on the Earth (bluish-white) and the Moon (grey). The viewpoint is fixed on the Earth and shows the moon rotating around the Earth. This rotation takes just over 27 days (a lunar month) but it takes nearly 30 days for the moon to go through all of its phases as viewed from Earth. At upper right shows the moon seen from Earth. The phases are the full moon, waning gibbous, half-moon, waning crescent, new moon, waxing crescent, half-moon, and waxing gibbous. Moonlight is simply sunlight reflected from the surface of the moon.

The scales are approximately correct for the relative sizes of the Earth and moon but the distance between the two has been greatly reduced. The plane of the moon orbit is, in reality, slightly tilted with respect to the plane of the Earth's orbit around the sun. The Earth and moon are locked in an orbit around each other and actually rotate about the pair's centre of gravity which is towards the surface of the Earth on the side facing the moon. This point is called the barycentre (Greek heavy centre). The moon continues to face the Earth as it orbits around, locked into synchrony by tidal (gravitational) forces. This is equivalent to the moon performing one revolution around its own axis for every complete revolution it makes around the Earth. The gravitational pull of the moon on the Earth distorts the oceans creating the tides.

Christmas-Coloured Viruses

Busy, Christmas-coloured viruses. This seamless tile design will soon be available as a fabric. Available now to licence and buy on merchandise. Some great versions here. Perfect for Christmas presents.

Double Slit Experiment Animated.

 I've just added a bunch of animations that illustrate the ever enigmatic double-slit experiment. The first is in 3D, the second is an orthographic 3D (effectively 2D)

4K UHD animation of the principle of Thomas Young's classic double-slit experiment. Waves hit a screen with two gaps. The gaps act as new wave sources, creating two sets of circular waves radiating outwards. These two new waves create an interference pattern as they superimpose on each other. The waves sum together producing higher peaks and deeper troughs at some points (constructive interference), whilst cancelling each other out at other points (destructive interference).

You can licence them from my Scientific.Pictures site.