APOD and General Astronomy Discussion Forum
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Fascinating! NGC 1140 is blue indeed. Its B-V index is 0.350, and its U-B index is -0.430. That is blue indeed!starsurfer wrote:NGC 1140
http://www.spacetelescope.org/images/potw1529a/
Copyright: ESA/Hubble & NASA
Full size: http://astronomynow.com/wp-content/uplo ... 0x2000.jpgESA/Hubble &NASA Press Release wrote:
This NASA/ESA Hubble Space Telescope image shows star clusters encircling a galaxy, like bees buzzing around a hive. The hive in question is the edge-on lenticular galaxy NGC 5308, located just under 100 million light-years away in the constellation of Ursa Major (The Great Bear).
Members of a galaxy type that lies somewhere between an elliptical and a spiral galaxy, lenticular galaxies such as NGC 5308 are disc galaxies that have used up, or lost, the majority of their gas and dust. As a result, they experience very little ongoing star formation and consist mainly of old and aging stars. On 9 October 1996, one of NGC 5308’s aging stars met a dramatic demise, exploding as a spectacular Type la supernova...
Ann wrote:Busy Bees
[img3="Credit: ESA/Hubble & NASAThis NASA/ESA Hubble Space Telescope image shows star clusters encircling a galaxy, like bees buzzing around a hive. The hive in question the an edge-on lenticular galaxy NGC 5308, located just under 100 million light-years away in the constellation of Ursa Major (The Great Bear).
Acknowledgement: Judy Schmidt"]http://cdn.spacetelescope.org/archives/ ... w1620a.jpg[/img3][hr][/hr]
Members of a galaxy type that lies somewhere between an elliptical and a spiral galaxy, lenticular galaxies such as NGC 5308 are disc galaxies that have used up, or lost, the majority of their gas and dust. As a result, they experience very little ongoing star formation and consist mainly of old and aging stars. On 9 October 1996, one of NGC 5308’s aging stars met a dramatic demise, exploding as a spectacular Type la supernova.
Lenticular galaxies are often orbited by gravitationally bound collections of hundreds of thousands of older stars. Called globular clusters, these dense collections of stars form a delicate halo as they orbit around the main body of NGC 5308, appearing as bright dots on the dark sky.
The dim, irregular galaxy to the right of NGC 5308 is known, rather prosaically, as SDSS J134646.18+605911.9
[img3="Credit: ESO/Marino et al."]https://cdn.eso.org/images/screen/potw1621a.jpg[/img3][hr][/hr]Using 39 of the 66 antennas of the Atacama Large Millimeter / submillimeter Array (ALMA), located 5000 metres up on the Chajnantor plateau in the Chilean Andes, astronomers have been able to detect carbon monoxide (CO) in the disc of debris around an F-type star. Although carbon monoxide is the second most common molecule in the interstellar medium, after molecular hydrogen, this is the first time that CO has been detected around a star of this type. The star, named HD 181327, is a member of the Beta Pictoris moving group, located almost 170 light-years from Earth.
Until now, the presence of CO has been detected only around a few A-type stars, substantially more massive and luminous than HD 181327. Using the superb spatial resolution and sensitivity offered by the ALMA observatory astronomers were now able to capture this stunning ring of smoke and map the density of the CO within the disc.
The study of debris discs is one way to characterise planetary systems and the results of planet formation. The CO gas is found to be co-located with the dust grains in the ring of debris and to have been produced recently. Destructive collisions of icy planetesimals in the disc are possible sources for the continuous replenishment of the CO gas. Collisions in debris discs typically require the icy bodies to be gravitationally perturbed by larger objects in order to reach sufficient collisional velocities. Moreover, the derived CO composition of the icy planetesimals in the disc is consistent with the comets in our Solar System. This possible secondary origin for the CO gas suggests that icy comets could be common around stars similar to our Sun which has strong implications for life suitability in terrestrial exoplanets. ...
[img3="Credit: ESA/Hubble & NASANearly as deep as the Hubble Ultra Deep Field, which contains approximately 10 000 galaxies, this incredible image from the NASA/ESA Space Telescope reveals thousands of colourful galaxies in the constellation of Leo (The Lion). This vibrant view of the early Universe was captured as part of the Frontier Fields campaign, which aims to investigate galaxy clusters in more detail than ever before, and to explore some of the most distant galaxies in the Universe.
Acknowledgement: Judy Schmidt"]http://cdn.spacetelescope.org/archives/ ... w1621a.jpg[/img3][hr][/hr]
Galaxy clusters are massive. They can have a tremendous impact on their surroundings, with their immense gravity warping and amplifying the light from more distant objects. This phenomenon, known as gravitational lensing, can help astronomers to see galaxies that would otherwise be too faint, aiding our hunt for residents of the primordial Universe.
MACS J1149.5+2223 is a galaxy cluster located approximately five billion light-years away. In 2012, it helped astronomers uncover one of the most distant galaxies ever discovered. Light from the young galaxy, magnified 15 times by the galaxy cluster, first shone when our 13.7-billion-year-old Universe was a mere 500 million years old — just 3.6 per cent of its current age! ...
With this pane of 16 Forever stamps, the Postal Service showcases some of the more visually compelling historic, full-disk images of the planets obtained during the last half-century of NASA space exploration. Eight new colorful Forever stamps – each shown twice – feature Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Click for full resolution. Credits: USPS/Antonio Alcalá © 2016 USPS
The souvenir sheet of four New Horizons stamps features two new stamps appearing twice. The first stamp is an artist’s rendering of NASA’s New Horizons spacecraft based on artwork created by APL’s Steve Gribben, while the second stamp shows an enhanced color image of Pluto taken by New Horizons near its closest approach to Pluto. Click for full resolution. Credits: USPS/Antonio Alcalá © 2016 USPS
