Tag Archives: Spacecraft

The ISSS used for teaching

I can still remember one of the few practical demonstrations I observed in my first year university physics class many years ago. This illustrated conservation of momentum. It involved our lecturer climbing on to the lecture room bench and standing on a plank of wood resting on (empty) beer bottles laid on their side (to reduce friction).

When he jumped forward by a small distance, the plank of wood shot back by a larger distance (conserving momentum). It was a risky experiment and several beer bottles broke.

I am not sure how many students appreciated the physical law being demonstrated. Practical demonstrations were not common in teaching those days. I suspect for many it just reinforced in their minds that this particular lecturer was, if not mad, at least eccentric.

In these more enlightened day I hope teachers use every advantage to practically demonstrate physical laws. Some of the videos being recorded on the International Space Station ISS could be useful for this.

Last week Astronaut Jeff Williams demonstrated the acceleration experienced inside the cabin during a planned ISS reboost. The ISS is reboosted periodically to maintain its orbit, and to prepare for visiting spacecraft, such as the space shuttle (a launch planned this week) and Progress vehicles.

Jeff’s experiment demonstrates that objects will continue in motion unless acted on by a force. In this case he shows that a free-floating body will move relative to the station when the station is accelerating.

A simple demonstration of an important physical law.

via YouTube – Space Station Reboost.


Awesome pictures from the Enceladus flyby

It’s amazing how much we are finding out about other bodies in the solar system these days. And the images we get back from some of our robotic spaceships can be incredible.

Here’s one taken by Cassini during a deep swoop past Enceladus, a moon of Saturn. This is an intriguing moon because it is thought to contain an ocean of water below an ice surface. It is also very active with plumes of material shooting at least 1000 km into space. In fact, these plumes may be contributing material to Saturn’s rings.

The swoop, early this month, was the deepest yet brought the spacecraft to about 100 km from the moon’s surface. it also took the craft through the heart of a plume enabling further investigation of its compositions and density. Scientists thinks the heating and tectonic activity arises from tidal forces caused by proximity to Saturn. There is even speculation that this energy and the presence of liquid water could provide conditions for life on the moon.

Thanks to Emily Lakdawalla at The Planetary Society Blog.

Click on Enceladus flyby for a compostie animation of images of the plumes.

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