Celestia Forums

I belive the oceans on Earth are blue due to the following reasons: 1 - Pure water is indeed blue (or indigo or violet). 2 - Blue and Violet light suffers more scattering in water than yellow and red light, making some of the blue light return to our eyes, while the red/yellow part of the visible sp...

Great pictures these.

I have a friend who did some very good astrophotographs with his webcam. See this link (in Portuguese):
http://geocities.yahoo.com.br/andre_moutinho/

His name is Andre Moutinho.

Perhaps what was meant by the statement that the Voyager is the fastest ever man built probe is that it's the probe with the largest specific mechanic energy (it is, energy per unit mass) ever built, which means it's the probe that will have the largest residual speed after it has completely escaped...

But what happens when you get a main sequence star orbiting a giant that's bigger than its roche lobe? To be precise, the main sequence star doesn't orbit aroung a giant star, both orbit around their center of mass, since their masses are similar, unless the main sequence star is "orbiting" a super...

I'm not an expert about close binary systems. But I belive that you would get something between a nova and a normal mass transfer between giants stars. Supposing that the main sequence star is a star like our Sun, which has a critical scape velocity of nearly 600 km/s. The infalling gas from the gia...

Thinking better, pehaps it's better to state that metals are not a kind of "degenerate matter". Thinking of a continuous transition from insulators to neutronium, as someone increases the pressure (and densities), we could state that metals are a kind of matter that is starting to become "degenerate...

Continuing my last thread posted in "Gas Giant Cores", I'm posting a classification of matter according to increased densities and pressures Note: I'm not supposed to write to this forum now, since I have a lot of homework to do, but I got addicted. Regardless of whether we classify some state of ma...

eburacum45 wrote: Obviously I was wrong to state that the centre of gas giants are degenerate to some extent; the useful definition of degenerate matter seems to be that matter in which the Pauli exclusion principle is the dominant component of the internal pressure. Perhaps not, unless it contradic...

Sorry if the message above was too patronising. I didn't realise you where a planetary scientist until I looked at your profile. Probably you know much more about this subject
I'm just a graduate student in Electronics, also taking a discipline in Astrophysics (MsC level).

Disclaimer: Don't take my answer as an absolute truth. It reflects only my current knowledge. OK, I know roughly how the distribution of stars breaks down in terms of spectral type (lots of M stars, very few O/B/A stars, and the rest in between). But is there any data that tells us the distribution ...

I've found a link to a site with a lot of interesting programs in Astronomy.

Project CLEA:
http://www.gettysburg.edu/academics/phy ... Abase.html

Link to programs:
http://www.gettysburg.edu/academics/phy ... rview.html

I hope you find these programs useful.

Personally I would like to classify ordinary metals as being a kind of "degenerate matter", so we could say that we can see degenerate matter everyday (See my post "Degenerate matter and metals") and also highlight some similarities that exists between white dwarf material and metals, but I don't th...

I've found an interesting link about this subject: http://cosmos.colorado.edu/stem/courses/ASTR1020-1/documents/chapter5/l5S6.htm Even though the author doesn't says that ordinary condensed matter is "degenerate matter", he points out that is the degeneracy pressure that prevents solids and liquids ...

Thanks granthutchison. You helped clearing this subject.

I'm not sure if the definition at Wikipedia is a consensus in the Scientific Community or only the point of view of the author of the article. In fact, everybody can edit articles in Wikipedia and in some older versions of this article (Degenerate Matter), it was stated that Conventional Solids wher...

I would like to know if is there any precise definition for the expression " degenerate matter". Is "degenerate matter" some not very well defined term, like " thermal energy", that is avoided in more advanced textbooks in Astrophysics or does it has a very precise definition? I would like to know i...

Thanks. Perhaps I had this problem with earth being too dark because my hardware is too old to recognise gamma setting in PNG, or because I didn't configured Celestia gamma setting (if this feature is available.), etc. Here's my system: Celeron 433MHz 96Mb RAM On board video adapter (ASUS motherboar...

Have any Celestia developer minded about gamma setting in computer systems? In Celestia 1.3.1 it seems that gamma setting was an overlooked subject, since the rendering of planet Earth looks too dark. I have a link to a page that explains very well about gamma correction in CRTs and desktop computer...

Indeed. Gamma correction would make things appear much more real in Celestia. I've found on the Internet a very good page explaining what is gamma correction and how to use it. I did some tests of my own, and I found out that the system gamma correction factor that should be used for Windows is roug...

Rigel, I'm sorry about this, but it seems that there's a problem with your star database (stardb2.1a). :( I've download your catalog (16 MB) file and when I tryied it I noticed an error. The problem is as follows: In your catalog the distance of Alpha Centauri pair (ALF Cen A and ALF Cen B) is the s...