Found images: 2016 February

[starsurfer]

NGC 2174
http://www.astroimager.net/Page-RHA-CCD-383.html
Copyright: Jim Janusz

[starsurfer]

Pacman Nebula (NGC 281)
http://astrophotography.aa6g.org/Astrop ... f8300.html
Copyright: Chuck Vaughn

[bystander]

Three Times the Fun
NASA | JPL-Caltech | Cassini | CICLOPS | 2015 Feb 22

[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. ...

[bystander]

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.

[starsurfer]

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.

How lovely, Wolf Rayet bubbles are some of the prettiest objects in the sky! However this image is false colour due to the infrared exposures and its "true" colour is red as its optical narrowband emission is dominated by Ha with either very little or no OIII. Also the nebulosity is sometimes referred to as Hen 3-519 as it was originally catalogued as a planetary nebula. Another point to mention is that in the sky this makes a pairing with the LBV nebula around the luminous blue variable star AG Carinae.

[starsurfer]

B8
http://www.astrofotos.at/index.php?view ... Itemid=134
Copyright: Robert Pölzl

[starsurfer]

IC 51
http://www.spacetelescope.org/images/potw1504a/
Copyright: ESA/Hubble & NASA

Click to view full size image

[starsurfer]

NGC 5053
http://bf-astro.com/ngc5053/ngc5053.htm
Copyright: Bob Franke

[Ann]

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

Ann

[starsurfer]

M33 widefield
http://www.astrosurf.com/ilizaso/orriak ... Q_U16m.htm
Copyright: Iñaki Lizaso

[bystander]

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

Check the link in the acknowledgement.

[geckzilla]

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]

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.

I suspected that it might not be yours, which is why I asked. But I wouldn't have seen yours if bystander had not shown me how to find it. I can see that the colors are slightly different in the two versions - yours is a different shade of blue.

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.

Ann

[geckzilla]

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.

Familiarity breeds contempt.

[starsurfer]

vdB13 and vdB16
http://www.alessandrofalesiedi.it/deep-sky/vdb13-16/
Copyright: Alessandro Falesiedi

vdB13 is the reflection nebula in the bottom right corner and vdB16 is the reflection nebula near the top. There are many dark nebulae in this area including B203 to the left of vdB13 and B204 to the right of vdB16.

[starsurfer]

vdB2
http://www.astrobin.com/221521/C/
Copyright: Tero Turunen

The dark nebula is catalogued as TGU H774 P19 and the round nebula to the left is the emission nebula Teutsch GN J0016.8+6546, which was discovered by the Deep Sky Hunters member Philipp Teutsch.

[starsurfer]

BBW 56
http://www.pbase.com/tango33/image/160396910
Copyright: Kfir Simon

[starsurfer]

Haffner 15
http://deeplook.astronomie.at/chile_bla ... fner15.htm
Copyright: CEDIC
Processing: Markus Blauensteiner

[starsurfer]

Jewel Box Cluster (NGC 4755)
http://www.eso.org/public/images/eso0940a/
Copyright: ESO/Y. Beletsky

Click to view full size image

[starsurfer]

NGC 2439
http://www.astropilar.com.ar/cumulos/NGC2439_1.html
Copyright: Ezequiel Bellocchio

[starsurfer]

NGC 4536
http://www.billionsandbillions.com/ngc_4536.html
Copyright: Warren Keller/SSRO

Click to view full size image

[bystander]

A Stellar Fingerprint (IRAS 12196-6300)
ESA Hubble Picture of the Week | 2016 Feb 29

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

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[hr][/hr]

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.

[Sandgirl]

Venus Saturn conjunction
Copyrights: Ihor Khomych
Suggested by: Mikhail Chubarets