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This image shows the bright centre and swirling arms of the spiral galaxy NGC 6300. NGC 6300 is located in a starry patch of sky in the southern constellation of Ara(The Altar) which contains a variety of intriguing deep-sky objects.
NGC 6300 has beautiful pinwheeling arms connected by a straight bar that cuts through the middle of the galaxy. While it may look like a standard spiral galaxy in visible-light images like this one, it is actually a Seyfert II galaxy.
Such galaxies have unusually luminous centres that emit very energetic radiation, meaning that they are often intensely bright in part of the spectrum either side of the visible. NGC 6300 is thought to contain a massive black hole at its heart some 300 000 times more massive than the Sun. This black hole is emitting high energy X-rays as it is fed by the material that is pulled into it.
This image of NGC 6300 was taken by the ESO Faint Object Spectrograph and Camera (EFOSC2) on the 3.58-metre New Technology Telescope (NTT). The NTT is based at ESO’s La Silla observing site, on the outskirts of the Atacama Desert in Chile, and was inaugurated in 1989. A black and white image of NGC 6300 was released at the time of the telescope’s inauguration — one of 31 images that were the first to be released from the NTT.
With its helical appearance resembling a snail’s shell, this reflection nebula seems to spiral out from a luminous central star in this new NASA/ESA Hubble Space Telescope image.
The star in the centre, known as V1331 Cyg and located in the dark cloud LDN 981 — or, more commonly, Lynds 981 — had previously been defined as a T Tauri star. A T Tauri is a young star — or Young Stellar Object — that is starting to contract to become a main sequence star similar to the Sun.
What makes V1331 Cyg special is the fact that we look almost exactly at one of its poles. Usually, the view of a young star is obscured by the dust from the circumstellar disc and the envelope that surround it. However, with V1331 Cyg we are actually looking in the exact direction of a jet driven by the star that is clearing the dust and giving us this magnificent view.
This view provides an almost undisturbed view of the star and its immediate surroundings allowing astronomers to study it in greater detail and look for features that might suggest the formation of a very low-mass object in the outer circumstellar disc.
Re: HEIC: A Young Star Takes Centre Stage (V1331 Cyg)
With its helical appearance resembling a snail’s shell, this reflection nebula seems to spiral out from a luminous central star in this new NASA/ESA Hubble Space Telescope image.
The star in the centre, known as V1331 Cyg and located in the dark cloud LDN 981 — or, more commonly, Lynds 981 — had previously been defined as a T Tauri star. A T Tauri is a young star — or Young Stellar Object — that is starting to contract to become a main sequence star similar to the Sun.
What makes V1331 Cyg special is the fact that we look almost exactly at one of its poles. Usually, the view of a young star is obscured by the dust from the circumstellar disc and the envelope that surround it. However, with V1331 Cyg we are actually looking in the exact direction of a jet driven by the star that is clearing the dust and giving us this magnificent view.
This view provides an almost undisturbed view of the star and its immediate surroundings allowing astronomers to study it in greater detail and look for features that might suggest the formation of a very low-mass object in the outer circumstellar disc.
This is a really detailed image of one of many interesting YSO's found in Cygnus. What I love about this image is that you get an impression that the stellar winds of the star are blowing the gas and dust outwards. I also like how the diffraction spikes are aligned with the corners of the image. An amateur widefield image of it by Antonio Sánchez shows its surroundings.
Judy Schmidt has also done an excellent version of this particular object as well.
Digital Model of 67P/Churyumov-Gerasimenko, February 2015 version
Image sources:
ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
ESA/Rosetta/NAVCAM
Image processing: Mattias Malmer
Click to play embedded YouTube video.
Re: Found Images: 2015 March
Posted: Sat Mar 07, 2015 5:25 am
by geckzilla
Mattias's work on that is fantastic. I saw him post it earlier today and was struck by the fact that I don't quite know how he did it so well.
The characteristic domes of the La Silla telescopes are closed off to protect the instruments from the harsh environment and icy weather. Amongst the plethora of white, the MPG/ESO 2.2-metre telescope is particularly distinctive due to its silver dome. On a normal night, as darkness falls, the telescope domes will open and begin their nightly routine of observing the cosmos.
Despite being located in a very dry area of the world, La Silla does occasionally experience some precipitation in the form of snow and a spattering of rain, as seen in this chilly picture taken by ESO Photo Ambassador Malte Tewes. However, although it does get cold in the Atacama Desert, where La Silla is located it rarely drops below zero degrees Celsius… So how can there be snow?
The dry air of the region plays a large part in this phenomenon. In dry conditions, snowflakes form and as they drop a small amount of evaporation occurs. This process removes heat from the snowflake, keeping it cold enough to survive the descent into a region where the temperature is above freezing. In short, the lower the humidity in the atmosphere, the higher the temperature at which it can snow — and so we can find snow in the Atacama Desert.
The galaxy UGC 8201, captured here by the NASA/ESA Hubble Space Telescope, is a dwarf irregular galaxy, so called because of its small size and chaotic structure. It lies just under 15 million light-years away from us in the constellation of Draco (the Dragon). As with most dwarf galaxies it is a member of a larger group of galaxies. In this case UCG 8201 is part of the M81 galaxy group; this group is one of the closest neighbours to the Local Group of galaxies, which contains our galaxy, the Milky Way.
UGC 8201 is at an important phase in its evolution. It has recently finished a long period of star formation, which had significant impact on the whole galaxy. This episode lasted for several hundred million years and produced a high number of newborn bright stars. These stars can be seen in this image as the dominating light source within the galaxy. This process also changed the distribution and amount of dust and gas in between the stars in the galaxy.
Such large star formation events need extensive sources of energy to trigger them. However, compared to larger galaxies, dwarf galaxies lack such sources and they do not appear to have enough gas to produce as many new stars as they do. This raises an important unanswered question in galaxy evolution: How do relatively isolated, low-mass systems such as dwarf galaxies sustain star formation for extended periods of time?
Due to its relative proximity to Earth UGC 8201 is an excellent object for research and provides an opportunity to improve our understanding of how dwarf galaxies evolve and grow.
This dramatic landscape in the southern constellation of Ara (The Altar) is a treasure trove of celestial objects. Star clusters, emission nebulae and active star-forming regions are just some of the riches observed in this region lying some 4000 light-years from Earth. This beautiful new image is the most detailed view of this part of the sky so far, and was taken using the VLT Survey Telescope at ESO’s Paranal Observatory in Chile.
At the centre of the image is the open star clusterNGC 6193, containing around thirty bright stars and forming the heart of the Ara OB1 association. The two brightest stars are very hot giant stars. Together, they provide the main source of illumination for the nearby emission nebula, the Rim Nebula, or NGC 6188, which is visible to the right of the cluster.
A stellar association is a large grouping of loosely bound stars that have not yet completely drifted away from their initial formation site. OB associations consist largely of very young blue–white stars, which are about 100 000 times brighter than the Sun and between 10 and 50 times more massive.
The Rim Nebula is the prominent wall of dark and bright clouds marking the boundary between an active star-forming region within the molecular cloud, known as RCW 108, and the rest of the association. The area around RCW 108 is made up of mostly hydrogen — the primary ingredient in star formation. Such areas are also known as H II regions.
The ultraviolet radiation and intense stellar wind from the stars of NGC 6193 seem to be driving the next generation of star formation in the surrounding clouds of gas and dust. As cloud fragments collapse they heat up and eventually form new stars. ...
This is an interacting group of galaxies in the constellation of Centaurus. The most southern of the trio is NGC 4905, the bluish spiral above and to the left of it is NGC 4903 and the largest galaxy with the long tidal tail is catalogued as ESO 443-34.
AM stands for "Arp, Madore" and is a catalogue of southern peculiar and interacting galaxies compiled by the astronomers Halton Arp and Barry Madore and published in 1987. While it has many more galaxies than the Arp Atlas, it is much more less well known.
