Starship Asterisk*

[img3="Credit: NASA/JPL-Caltech/Space Science Institute"]http://s3.amazonaws.com/ciclops_ir_2015 ... 9866_2.png[/img3][hr][/hr]

Three of Saturn's moons — Tethys, Enceladus, and Mimas — pose for a group photo with the rings thrown in to add to the wonder.

Tethys (660 miles or 1062 kilometers across) is above the rings in this image, while Enceladus (313 miles or 504 kilometers across) is below, almost center. Mimas (246 miles or 396 kilometers across) poses below and to the left of Enceladus.

This view looks toward the sunlit side of the rings from about 0.42 degrees above the ringplane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Dec. 3, 2015.

The view was acquired at a distance of approximately 837,000 miles (1.35 million kilometers) from Enceladus. Image scale is 5 miles (8 kilometers) per pixel. Tethys was approximately 1.2 million miles (1.9 million kilometers) away with an image scale of 7 miles (11 kilometers) per pixel. Mimas was approximately 1.1 million miles (1.7 million kilometers) away with an image scale of 6 miles(10 kilometers) per pixel. ...

[img3="Credit: ESA/Hubble & NASA
Acknowledgement: Judy Schmidt"]http://cdn.spacetelescope.org/archives/ ... w1608a.jpg[/img3][hr][/hr]

Sparkling at the centre of this beautiful NASA/ESA Hubble Space Telescope image is a Wolf–Rayet star known as WR 31a, located about 30 000 light-years away in the constellation of Carina (The Keel).

The distinctive blue bubble appearing to encircle WR 31a, and its uncatalogued stellar sidekick, is a Wolf–Rayet nebula — an interstellar cloud of dust, hydrogen, helium and other gases. Created when speedy stellar winds interact with the outer layers of hydrogen ejected by Wolf–Rayet stars, these nebulae are frequently ring-shaped or spherical. The bubble — estimated to have formed around 20 000 years ago — is expanding at a rate of around 220 000 kilometres per hour!

Unfortunately, the lifecycle of a Wolf–Rayet star is only a few hundred thousand years — the blink of an eye in cosmic terms. Despite beginning life with a mass at least 20 times that of the Sun, Wolf–Rayet stars typically lose half their mass in less than 100 000 years. And WR 31a is no exception to this case. It will, therefore, eventually end its life as a spectacular supernova, and the stellar material expelled from its explosion will later nourish a new generation of stars and planets.

bystander wrote:Blue Bubble in Carina (WR 31a)
ESA Hubble Picture of the Week | 2016 Feb 22

[img3="Credit: ESA/Hubble & NASA
Acknowledgement: Judy Schmidt"]http://cdn.spacetelescope.org/archives/ ... w1608a.jpg[/img3][hr][/hr]

Sparkling at the centre of this beautiful NASA/ESA Hubble Space Telescope image is a Wolf–Rayet star known as WR 31a, located about 30 000 light-years away in the constellation of Carina (The Keel).

The distinctive blue bubble appearing to encircle WR 31a, and its uncatalogued stellar sidekick, is a Wolf–Rayet nebula — an interstellar cloud of dust, hydrogen, helium and other gases. Created when speedy stellar winds interact with the outer layers of hydrogen ejected by Wolf–Rayet stars, these nebulae are frequently ring-shaped or spherical. The bubble — estimated to have formed around 20 000 years ago — is expanding at a rate of around 220 000 kilometres per hour!

Unfortunately, the lifecycle of a Wolf–Rayet star is only a few hundred thousand years — the blink of an eye in cosmic terms. Despite beginning life with a mass at least 20 times that of the Sun, Wolf–Rayet stars typically lose half their mass in less than 100 000 years. And WR 31a is no exception to this case. It will, therefore, eventually end its life as a spectacular supernova, and the stellar material expelled from its explosion will later nourish a new generation of stars and planets.

Ann wrote:That blue bubble in Carina is beautiful indeed, false color of not. Is it your work, Geck?

bystander wrote:

Ann wrote:That blue bubble in Carina is beautiful indeed, false color of not. Is it your work, Geck?

Check the link in the acknowledgement.

geckzilla wrote:

bystander wrote:

Ann wrote:That blue bubble in Carina is beautiful indeed, false color of not. Is it your work, Geck?

Check the link in the acknowledgement.

As usual, they've done their own version of it after viewing mine. And although some see no distinction between false color and representative color, I would call this representative rather than false. It is a combination of wideband infrared and red wavelengths. To force it to be red because of the biases imposed by our human eyes which cannot see infrared wavelengths would be false to me.

Ann wrote:For whatever reason, I don't mind the false - or representative - color here at all. But just yesterday I posted the well-known Hubble picture of I Zwicky 18, because I wanted to show another galaxy than M82 that has red outflows. The blue-colored Ha nebula of I Zwicky 18 in the Hubble picture irritated me.

[b][i]Credit: ESA/Hubble & NASA Acknowledgement: [url=https://www.flickr.com/photos/geckzilla/14433188265]Judy Schmidt[/url][/i][/b]

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Showcased at the centre of this NASA/ESA Hubble Space Telescope image is an emission-line star known as IRAS 12196-6300.

Located just under 2300 light-years from Earth, this star displays prominent emission lines, meaning that the star’s light, dispersed into a spectrum, shows up as a rainbow of colours marked with a characteristic pattern of dark and bright lines. The characteristics of these lines, when compared to the “fingerprints” left by particular atoms and molecules, can be used to reveal IRAS 12196-6300’s chemical composition.

Under 10 million years old and not yet burning hydrogen at its core, unlike the Sun, this star is still in its infancy. Further evidence of IRAS 12196-6300’s youth is provided by the presence of reflection nebulae. These hazy clouds, pictured floating above and below IRAS 12196-6300, are created when light from a star reflects off a high concentration of nearby dust, such as the dusty material still remaining from IRAS 12196-6300’s formation.