My name is Guillem Aumatell and I'm from Barcelona. I studied physics in the U.A.B. (Universitat Autonoma de Barcelona) and astrophysics in U.L.L. (Universidad de La Laguna), F.S.U. Jena (Friedrich Schiller Universität Jena) and the U.B. (Universitat de Barcelona). Actually I'm working in Duisburg-Essen University as PhD student. The department where I investigate, is dedicated to make experiments about planet formation.
Ummmhhhh. First question. How experiments about planet formation can be done? Do we "create" planets??
Well, not really. Our objective is to know which processes take place in order to form different kind of objects that orbit around stars, that is, planets (and their moons), dwarf planets, asteroids and comets. Like for example our solar system.
As maybe you know, actually more than 500 planets around other stars -that are not our Sun- have been discovered. That proves that the mechanisms which caused the formation of our solar system, are universal and take place in other regions of the Cosmos.
Where do the planets come from? What are they made of?
These are questions not easy to answer, but in our laboratory we try to reproduce the phenomena that could happen during the first stages of planet formation. Nowadays it's well known that planets are formed in what is called a protoplanetary disk. They are basically constituted by gas and tiny fractions of dust that surround stars at their first stage of life. Even though, the main interest in my experiments is another one... WATER ICE! Beyond what is known as "snow line", this gas and dust is far enough from the sun that water (normally in gas phase due to low pressures of protoplanetary disks) condenses into ice. In fact, water ice has been detected in many bodies from our own solar system, for example:
*Mars
*Comets
*Asteroids
*Saturn rings
*Icy moons
How did they form? What role plays water ice?
Well, I'm not yet totally ready to answer this questions, but I hope I'll be able to suggest some conclusions in the future (no much far I hope). In order to create bigger bodies, the ice aggregates have to collide and stick. This is a process that, taking the necessary conditions, can be observed in the laboratory. In fact, we are the first group who has recorded ice sticking in conditions similar to those we could meet in protoplanetary disks (low pressure among many others).
The videos below have a relatively low quality. That's because for higher quality, the videos should be to "heavy" (about 170 Mbytes), and I think that it is not necessary to wait so long until they are downloaded.
Enjoy them!
In the video above are visible several ice aggregates floating on a cold surface (I'll explain how they levitate in another post). The numbers that can be seen on the upper left corner, correspond to the time that already has past (milliseconds) while down right a scale bar is shown (in millimeters). If you pay attention, you will be able to see how 2 pieces hit, stick and then travel together.
In this second video, the ice aggregates are levitating on an aluminum plate of about 5 centimeters. As it can be seen, the images do not have as much zoom as the first video, but interactions between aggregates can be observed. Be patient, it is about 10 Mbytes, maybe takes a little bit time.
I wait for your comments!!
