Starship Asterisk*

Deesqrd wrote:Planets and Sun are rotating in reverse.

Uwe wrote:"No, you are NOT the center of the universe!"
In Fact that's hard to be proven, to be completely honest. ^^
A better expression would be "Maybe you ARE the center of the universe, but who gives a F***!"
Thanks for the nice video, a little annoying music (yep, I'm getting old).

geckzilla wrote:I have an interest in the way we visualize the larger stars. I know we've never resolved any star other than our sun into much more than a blurry blip 4 pixels across, so we may never have a direct image of one, but do we know enough about them to guess a little better at their appearance? For instance, would the edge of the star be so clearly defined or would it be kind of tattered like a cloud? Or maybe blurred like a fog settled close to the ground? Or perhaps there is a visible layering effect? I also wonder if we could look at the star a bit longer with our own eyes without some sort of filter.

Jim Kaler wrote about Betelgeuse:
The star is so big that its angular diameter is easily measured. Indeed it was the first to have such a measure, of 0.047 seconds of arc, from which we find a true radius of between 4.1 (compromise distance) and 4.6 (larger distance) AU, considerably greater.

However, the star is surrounded by a huge complex pattern of nested dust and gas shells, the result of aeons of mass loss, that extends nearly 20,000 AU away (Betelgeuse so far having lost over a solar mass). That, an extended atmosphere, and the pulsations make it difficult to locate an actual "surface" to tell just how large the star actually is.

Moreover, because of changes in gaseous transparency, the "size" of the star depends on the color of observation. Long-wave infrared measures give a vastly larger radius of up to 5 AU and greater, as big as the orbit of Jupiter, while shorter-wave infrared light gives as small as 3 AU. Moreover still, infrared measures reveal Betelgeuse to be shrinking (by some 15 percent over about 20 years), and other measures show that the star is not even round, but somewhat oval.

ro-star wrote:also, to answer the question in the video, how could one possibly ever imagine a diameter of 2.8 billion km, that is too easy to imagine;
given Saturn's orbit has a radius of 1.46 billion km, your 2.8 billion km diameter star would fit inside Saturn's orbit, how much easier than that could it get?

DRAKULIAN wrote:This video is a classic and still suffers from the same problem it did ages ago. That is to say, why did the creator of this video purposely leave out the planet URANUS?

SomeSleeplessGuy wrote:
Is my maths wrong, or should it take about 1500 years to fly around the supergiant, not 1100?
d=2.8 bnkm
circumference = pi(d) = 8.8bnkm
vel = 900km/h
therefore flight duration = 9.77 million hours = 1535 years.

http://en.wikipedia.org/wiki/VY_Canis_Majoris wrote:
<<VY Canis Majoris (VY CMa) is a red hypergiant in the constellation Canis Major. It is one of the largest known stars by radius and also one of the most luminous of its type. It is approximately 1,420 ± 120 solar radii (6.6 astronomical units), about 1,975,000,000 kilometres in diameter, and about 1.2 kiloparsecs (3,900 light-years) distant from Earth. VY CMa is a single star categorized as a semiregular variable and has an estimated period of 2,000 days. It has an average density of 5 to 10 mg/m3. If placed at the center of the Solar System, VY Canis Majoris's surface would extend beyond the orbit of Jupiter, although there is still considerable variation in estimates of the radius, with some making it larger than the orbit of Saturn. The first known recorded observation of VY Canis Majoris is in the star catalogue of Jérôme Lalande, on 7 March 1801, which lists VY CMa as a 7th magnitude star. Further 19th-century studies of its apparent magnitude demonstrate that the star has been fading since 1850.>>

http://en.wikipedia.org/wiki/NML_Cygni wrote:
<<NML Cygni or V1489 Cygni is a red hypergiant star and the largest star currently known, at about 1,650 times the Sun's radius or 7.67 a.u. It was discovered in 1965, by Neugebauer, Martz & Leighton. It is one of the extreme luminous supergiant stars. Its distance from Earth is estimated to be around 1.6 kpc, or about 5,300 light-years. This star has a dusty environment surrounding it, and it exhibits a [ lima / fava / string / human ] bean-shaped asymmetric nebula which is coincident with the distribution of its H₂O vapor masers. It is a semiregular variable star with a period of around 940 days. The bolometric luminosity for this star is near 3 × 10⁵ L☉. Its bolometric magnitude is around −9.0. It is one of the most luminous cool hypergiant stars.

From the observations, it is estimated that this star has two discrete optically thick envelopes of dust and molecules. The optical depth of the inner shell is found to be 1.9 while that of the outer one is 0.33. The star has one of the largest mass loss rates at around 2 × 10^-4 M☉ per year. These dust envelopes are formed due to the strong post-mainsequence wind velocity and the high mass emission rate. The post-MS wind velocity is 23 km/s. Because of its unique location within the Milky Way the star does not dominate its local interstellar environment.

NML Cyg is a massive oxygen-rich star. Its composition began to be revealed with the discovery of OH masers (1612 MHz) in 1968 (Wilson and Barrett). The presence of molecules like H₂O, SiO, CO, HCN, CS, SO, SO₂ and H₂S was also revealed in the later years>>