AD ASTRA...       page 2

(last update: 21. Nov 1999, look there and immediately below)

Exoplanets from Berkeley/SFSU (by Marcy, Butler et al.)
This is the homepage of the most successful planet hunters nowadays. They present their results in a scientific manner, but the radial velocity curves are not difficult to interpret: the mean deviation is easily recognized without deep scientific knowledge - it's simply graphical visible.

K is the amplitude of the radial velocity, or more explicit, the maximum velocity in the line of sight relative to the average value. And e is again the (numerical) eccentricity with range from 0 (circle) to values near 1.

Also there are several tables, ordered in diverse manners to underline certain aspects of the found substellar companions. But one thing is important at this: for the large intrinsic effects, which have a great impact in statistical measures, nobody can be sure, if this first results are anyway a clue to the real distribution of such objects. First, the lower mass stars carry a greater chance of detection of companions, because there velocity is stronger affected by equal companion masses. Second, of course, the more mass the companion has and also the more close he is to it's star, the more likely it's detected.

But the apparent lack of brown dwarfs is very probable true, because they have greater masses then planets. But there is a tiny chance, that different mean distances between stars and companions of different mass can affect this statistics too in an unpredictable manner at least at now.

And finally, even the most successful planet hunters will need many further years for the first detection of an earth sized planet, because this requires an increase in the technology by a factor of at least 100 (so far sun like stars are concerned; the exotic pulsar planets are simply another category).

Discoverers of 51 Pegasi TelescopeMayor & Queloz Extrasolar Planets
These are the also famous discoverers of the first confirmed extrasolar planet associated with a star resembling our sun. The announcement from 1.2.1999 of them was also a new record: the lowest lower limit of such a planet up to now with only 0.42 (uncertainty about 4 %) Jupiter masses. Meanwhile (spring 2000) they found even two planets with masses probably below or a least comparable to that of Saturn or about 25 % of that of Jupiter --- safe for a not too strong tilt of their orbits, which could imitate a lower mass by a really higher one. The effective temperature they also list is of course only valid for a so-called black body, i.e. a surface, which absorbs all incoming radiation. But it can be not far less... The other remarks especially about designations are valid as for the above site of Marcy & Butler and of the Extrasolar Planets Encyclopedia (page 1 of astronomy).


surface of 70 Vir companions moon?Extrasolar Visions    alternative domain name (same IP address)

still not reliable --- at last slow loading

The best thing and main subject of this aesthetical page is to show artists conceptions of surfaces and space appearances of extrasolar companions (Extrasolar Store/Purchasing Art, see also references in the news section).

You can witness a combination of scientific knowledge and a bit of science fiction like fantasy in several dozen pictures. Clearly this will remain for decades the only possibility to "see" extrasolar planets and brown dwarfs in this clarity, but of course in a speculative manner.

Along with every picture there is a caption to the painting, which can also be purchased as photoprint or slide. This site uses frames and relies partly respective temporarily also on Java features.


Space Movie Archive
This seems indeed to be the largest collection of movies/animations of space related matters in the Internet. For it's a French site, you can of course also request a French version of the page and it's also possible to choose between versions with frames, without frames and even without inline pictures for pure text browsers like Lynx (but this last one will also decrease access times for graphical browsers, of course).

What's very important: all movies are clearly designated with their sizes, so you can choose together subject and size of the videos you want to download.

It contains a mixture of astronomical, space flight and science fiction animations; so you should find nearly everything existing as digitized movie.

The most of them are MPEG animations, so it should pose no problem to play them on any operating system and even viewing during download as streaming video with a plugin should be possible for most users, if they are NOT compressed files.

But there are other formats too, and there the problems may arise, if you find not an appropriate player. Therefore you should first check out (see for example at bottom of the entry page of that homepage), if you can get a working animation player for your platform.

For LINUX users I recommend Xanim. This is available at  Xanim homepage 1 and three further mirror sites and capable of playing most video formats (AVI, Quicktime (not version 3.0 yet!), simple MPEGs and possible others).

As ever this requires an highest-as-possible bandwidth of your Internet connection and also a considerable amount of available storage, if you want make full use of this great archive.


Scientific Movies
 IAA (TAT), Tübingen, Germany

This homepage of a scientific institute located at the university of Tübingen in Germany contains along with other things a series of scientific movies with explanations. For interested people matters of the theory of relativity are well illustrated with MPEGs.

There were also framed and non-framed versions along with English and German descriptions (they are not consequently seperated).


But recently the site has undergone a major revision and now you should click directly on the new planned project Xpulsar@home (a pendant to SETI@home) or one of the links SPH, Relativity and below to proceed...

German Flag
Da diese homepage einen Mischmasch von Englisch und Deutsch beinhaltet, mixe ich dies hier ausnahmsweise ebenfalls. V.a. relativistische Effekte werden hier mit guten MPEG-Animationen illustriert. Es ist das Institut für Astronomie und Astrophysik in Tübingen des vielleicht manchem bekannten Professor Ruder, einem Original und Experten für Allgemeine Relativitätstheorie.

Es gab hier ebenfalls verschiedene Versionen mit und ohne frames, sowie in Deutsch und Englisch (teils etwas inkonsequent getrennt).


Vor Kurzem wurde die Seite aber stark überarbeitet und jetzt fängt das für Außenstehende Interessante mit dem geplanten Projekt Xpulsar@home an (analog zu SETI@home) und setzt sich mit den Links ab SPH fort.


NCSA Relativity Movies   online again!

 NCSA Movies about several Scientific Topics
Another site presenting movies of astrophysical/relativistic contents. There are offered MPEGs and good old Quicktimes, playable on every platform. Keep in mind, that the moderate sized animations show results of calculations and the natural processes are barely imaginable or recognizable for our brains. There are more scientific subjects presented also with Real Video in the second URL (if you don't have or know Real Video, look on my computer page. 


European Southern ObservatoryVery Large Telescope site

The mankinds largest telescope, now the first part already finished, is operated by the European Southern Observatory organization at the Cerro Paranal in Chile in the high Atacalma desert. This is the finest location for astronomical observations so far found: only hardly one week every year is not totally unclouded and the seeing is the best in both respects of the astronomers enemy, earths atmosphere: first the blurring (causes the stars to seemingly blink and jump around) is the lowest found yet and also the Atacama desert is along with the antarctic ice shield the driest place on our planet (the Guiness book reports for a place in this desert absolutely no rain for a time of 400 years!). In the years coming a total of four 8 m telescopes will be operational, therefore creating a total aperture equivalent of a 16 m telescope. Also interferometry with electronic measures will be conducted and the adaptive technique of the mirrors will enable to get the full resolution at last in the near infrared, probably also in the visible light.

The first pictures of the first unit are already present at this site. This jewel of the ESO will certainly show sensational pictures in the time to come.

At now mainly the technical aspects and the building process are described, of course.


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