Constellation Program

I remember NASA used to have so called "constellation program" several years ago. Briefly, they were planning to send human beings to the Moon again.

This program seems the preparation to build a stronghold on the Moon for the space exploration of the further celestial bodies. The gravity on the Moon is less than 20% of that of the Earth. If some resources are available there, people can build a base and launch rockets by using less energy. The Moon has the potential to be a gate way to deep space.

But this program was canceled because of its huge cost. You know sending humans requires more cost and technologies rather than sending machines. However, this means autonomous systems can play an important role on the efficiency of exploration. In addition, sophisticated autonomous technologies will also reduce the cost of manned exploration in the future. I think the current trend in space exploration is an unmanned autonomous spacecraft. So robotics will gain more focus in the future. (yet, already?)


Colored Coulds

You may know the atmosphere can be divided into several layers. What is the furthest layer from here? Yes, it's the ionosphere. This layer plays an important role for radio communication. The molecules in the layer are ionized by the radiation from the Sun. These ionized molecules reflect radio waves from the ground. (of course, such waves with higher frequency can go through the layer though...) That is, we can send radio waves beyond the horizon. But this layer changes dynamically. So it is important to understand the phenomena and mechanism of it.

This picture is the experiment to observe winds in the ionosphere. The equipment of the rocket released the vapor of lithium. The flame color of lithium is red, so you can see a red clound in the image. It seems there are some other types of metal released. The scientists can figure out the dynamics of the ionosphere by analysing the transition of these clouds.

You can see the details about the experiment here.