Posts by Ynjevi

by Ynjevi
17.05.2004, 12:04
Forum: Physics and Astronomy
Topic: 2 Extremely Hot Jupiters
Replies: 9
Views: 2965

Re: 2 Extremely Hot Jupiters

How they know that now are gas giants?Were the others terrestrial giants?Anyway,it was discovered planets with almost the same massof Jupiter near the star,like 51 Pegasi.I don?t understand why should be a new class of planet.Why? The newly-discovered planets orbit much closer than typical 51 Pegas...
by Ynjevi
13.05.2004, 19:06
Forum: Add-on development
Topic: Barzan Wormhole
Replies: 16
Views: 4941

Re: Barzan Wormhole

*sigh* no more Borgs!

But the models, and the wormhole especially... WOW!! 8O
by Ynjevi
13.05.2004, 13:56
Forum: Textures
Topic: Criticism wanted: geologically old terrestrial world
Replies: 15
Views: 5071

Re: Criticism wanted: geologically old terrestrial world

Hmm... I was thinking about a planet that would be something like between the Earth and Mars: a "super-Mars" which would have much denser atmosphere than Mars', and no plate tectonics. It would orbit further out from the central star so it wouldn't get torched so quickly. Climate would be something ...
by Ynjevi
12.05.2004, 10:29
Forum: Textures
Topic: Criticism wanted: geologically old terrestrial world
Replies: 15
Views: 5071

Re: Criticism wanted: geologically old terrestrial world

I seem to recall that the Earth's plates tend to form a new super-continent every 250MYears or so. (Hmm -- that's about the same as the sun's orbital period around the galactic center, but I don't see how they could be related.) Actually Pangaea formed about 300 million years ago, and the next supe...
by Ynjevi
22.04.2004, 07:23
Forum: Celestia Users
Topic: Question about Galatea?
Replies: 8
Views: 2442

Re: Question about Galatea?

They won't break apart (yet) but their orbits decay.

~ Jyri
by Ynjevi
21.04.2004, 18:00
Forum: Physics and Astronomy
Topic: Atmospheric circulation on hot-Jupiter planets
Replies: 3
Views: 2558

Re: Atmospheric circulation on hot-Jupiter planets

Good timing for that question, I spotted just today following abstract: Changing face of the extrasolar giant planet HD209458B (Cho et al.) High-resolution, fully-turbulent atmospheric flow simulations of the tidally-locked extrasolar giant planet, HD209458b, show large-scale spatio-temporal variabi...
by Ynjevi
19.04.2004, 07:09
Forum: Physics and Astronomy
Topic: Triple Shadow transit on Jupiter
Replies: 51
Views: 21615

Re: Triple Shadow transit on Jupiter

Don't blame Celestia :) . That middle dot is not a shadow but Ganymede. Io is not contrasted enough to be visible. Except for time it looks just correct. You have to take the lightspeed into account, so Jupiter must be viewed from Earth. So this will explain why I'm seeing the transit at approximate...
by Ynjevi
18.04.2004, 14:45
Forum: Physics and Astronomy
Topic: Triple Shadow transit on Jupiter
Replies: 51
Views: 21615

Re: Triple Shadow transit on Jupiter

Jeam Tag wrote:Hello, see
http://skyandtelescope.com/news/article_1241_1.asp for more info (and a short movie).
Curiously, can't reproduce it in Celestia. Someone could see it running?
Jeam


It does work if you go to Earth, look at Jupiter and allow light transit delay.

~ Jyri
by Ynjevi
05.04.2004, 10:53
Forum: Physics and Astronomy
Topic: I have question that's been nagging at me for the past hour.
Replies: 12
Views: 5559

Re: I have question that's been nagging at me for the past hour.

Indeed, Betelgeuse is way too distant to harm us in any way.

Betelgeuse's mass is thought to lie between 12 and 17 solar masses (although I've seen higher estimates). If its mass is near the lower end (or under) of the range, it may even not explode as supernova.

~ Jyri
by Ynjevi
01.04.2004, 20:49
Forum: Physics and Astronomy
Topic: I have question that's been nagging at me for the past hour.
Replies: 12
Views: 5559

Re: I have question that's been nagging at me for the past hour.

I don't think Sirius is massive enough to die as a supernova either. Though I don't know what is the nearest star that could... There don't seem to be any supergiants within about 30 pc of Sol - I think epsilon aquilae might be the closest (an F0 Ia supergiant). Epsilon Aquilae a supergiant? Well, ...
by Ynjevi
01.04.2004, 13:33
Forum: Physics and Astronomy
Topic: I have question that's been nagging at me for the past hour.
Replies: 12
Views: 5559

Re: I have question that's been nagging at me for the past hour.

Hmmm, what about Sirius? It is only 8 light years away and it is a type A0. Would we see and or get any effect from it as it goes through its midlife crisis and death? I don't know how long it takes Sirius A to change to red giant (under 1 Gyr anyway), but it's well enough to travel far away from t...
by Ynjevi
01.04.2004, 10:43
Forum: Celestia Users
Topic: HST model orientation correct?
Replies: 4
Views: 1720

Re: HST model orientation correct?

I just remember reading that the opening would not point anywhere near the Earth because the very strong light reflection would damage the internal devices. In it's current orientation, it seems that this could be a possibility. Hubble is regularly pointed towards the Earth for flat images. For exa...
by Ynjevi
15.03.2004, 13:05
Forum: Physics and Astronomy
Topic: Sedna
Replies: 44
Views: 14616

Re: Sedna

This is told now: * provisional designation 2003 VB16 * perihelion 76 AUs, aphelion near 900 AUs -> it is not a KBO but possibly a Inner Oort Cloud object * orbital period 12,260 years * it was not detected with Spitzer or IRAM, thus * surface reflectivity lies between 20%-100% * and size between 1/...
by Ynjevi
15.03.2004, 12:42
Forum: Physics and Astronomy
Topic: Sedna
Replies: 44
Views: 14616

Re: Sedna

As far as I'm concerned, Pluto is a planet purely for historical reasons, and that's how it'll stay in my opinion. If more KBOs had been discovered in the months/years immediately after Pluto was discovered in 1930, we'd almost certainly not be having this argument now, since we'd think they're all...
by Ynjevi
15.03.2004, 07:54
Forum: Physics and Astronomy
Topic: Sedna
Replies: 44
Views: 14616

Re: Sedna

I don't think it makes sense to call Sedna (or Pluto) planet. There are probably dozens of bodies with diameters over 2,000 km.
by Ynjevi
12.10.2003, 13:06
Forum: Celestia Users
Topic: eps indi
Replies: 3
Views: 1399

Re: eps indi

orion wrote:hi,
does anyone know where i can get an add-on for the brown dwarf system around epsilon indi?


Yes, see Grant Hutchison's near stars add-on. It includes the Epsilon Indi brown dwarf binary.
by Ynjevi
09.10.2003, 16:23
Forum: Physics and Astronomy
Topic: New satellite... again
Replies: 14
Views: 8663

Re: New satellite... again

S/2003 U 3:

a = 0.0979247 AU
e = 0.7826995
i = 50.65125°
P = 1693.88 days (4.64 years)
Peri. = 77.97150°
Node = 18.01185°
H = 12.7 mag

MPEC 2003-T58
by Ynjevi
09.10.2003, 06:19
Forum: Physics and Astronomy
Topic: Why so few supernova's?
Replies: 2
Views: 2982

Re: Why so few supernova's?

1) Even supernovas are very dim when viewed from hundreds of millions of light years away. 2) They are not visible for a long time. 3) It is impossible tell when and in which galaxy supernova explodes in a given time. That means we need powerful search telescope with a large field of view, which lea...
by Ynjevi
07.10.2003, 16:04
Forum: Celestia Users
Topic: milky way not right
Replies: 4
Views: 1502

Re: milky way not right

Milky Way is probably very similar to galaxies such as NGC 3953 and NGC 7723. There's great map of Milky Way in an Atlas of the Universe site.
by Ynjevi
07.10.2003, 15:16
Forum: Add-on development
Topic: End of the world
Replies: 17
Views: 5957

Re: End of the world

ElPelado wrote:Jack Wrote:
the yellowstone super-volcano
what is it??


Yellowstone is a huge caldera (80x65 km) of a gigantic volcano which has exploded three times in the past 2.1 million years much more powerfully than any modern volcano.

See Yellowstone Volcano Observatory FAQ

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