Monday, April 28, 2014

Space elements providers

Supernova explosions of the star is the only source of heavier elements in the Universe. All the heavier elements (like iron, are more heavy ones) are being created during these explosions and are spread around the space to create later planetary systems. One of these remarkable explosions happened about 10 000 years ago in the constellation of Cygnus. It created Veil Nebula placed about 1440 light years away which is now 80 light years large and still expands at speed 170km/s. Small part of this nebula is Pickering's Triangle presented below.
It was pictured by me about half year ago, but a few days ago I found these files during the disk clean up. Red regions corresponds to the hydrogen, and blue ones to oxygen. It is bicolor composition of two monochrome frames shot with the proper narrowband filters. 

Clear skies!

Wednesday, April 23, 2014

Remote worlds in the Markarian's Chain background

Here we have: Markarian's Chain of galaxies. Starting from top left we have two small galaxies NGC4458 and 4461, then Eyes Galaxies NGC4438-4435, and then giant elliptical galaxies M86 and M84 surrounded by few other large ones. All these galaxies are in the core part of Virgo Galaxy Cluster - about 60 million light years away. Messier 86 is the largest galaxy in the frame. This elliptical giant is moving towards us at speed 244km/s. This galaxy is linked with several filaments of ionized gas with galaxy NGC4438. Since it moves fast through intercluster medium it leaves behind a long trail of hot gas. Teh M86 galaxy has numerous globular clusters - there are about 3800 known ones. 
Messier 84 is another big elliptical galaxy in the frame. This one is about 8 million light years more distant than M86 and is moving away from us at speed over 1000km/s. Radio and HST observations of M84 indicates presence of supermassive black hole inside (its mass is estimated for 1.5 billion of solar masses).
The Eyes Galaxies (little above and to the left from frame center) are NGC4435-4438. This formation is also known as Arp 120. They are about 52 million light years away. The smaller one is NGC4435 - it has relatively young (about 190 million years) stellar population on its central regions whose origin may be the interaction with NGC4438. This latter one is the most curious interacting galaxy in the Vigro cluster. The mechanism that heats its nuclear source is uncertain. It can be a starburst region, or a black hole. This galaxy shows distorted disk with long tidal tails due to interactions with local galaxies. 
There are also plase for very remote object in this picture. Among Markarian's Chain galaxies you can easily spot many other medium sized objects placed a few hundred million light years away. But I managed to identify (using SDSS) one that is 4.4 billion light years away (redshift z=0.391) and another one 5.1 billion light years away (z=0.482) that you can identify below. Both are galaxies, not spectacular at this picture, but they are not expected to be spectacular at amateur pictures anyway :)

Clear skies!

Saturday, April 12, 2014

Moonwalk - lunation 12.1

In the center of the picture below there is Gassendi crater (111km). The crater has been inundated by lava during the formation of nearby Mare Humorum (below the crater), so only the rim and central peaks remains above the surface. The crater rim is eroded, but still its circular shape is clearly visible. The rim rises above the crater floor from 200 to 2500 meters. Also at crater floor there is rilles system called Rimae Gassendi.
There are also a few other features at the picture. Second largest crater at the picture is Mersenius (85km) to the left and bottom of the Gassendi. Between these craters there are rille system designated Rimae Mersenius of length about 230km. At the picture bottom at the border of Mare Humorum there is Rupes Liebig - a 180km long fault line called from near by crater Liebig (the Sun is just rising over it at the picture bottom).

Tuesday, April 8, 2014

Moonwalk - lunation 7.1

Moon is almost in the middle on his way to be a Full Moon, so many interesting features come up from the shadow near the terminator line. Between Sinus Asperitatis (Bay of Roughness - top part of the first picture) and Mare Nectaris (Sea of Nectar) there are few prominent craters. The first one from the top is Teophilus - large impact crater. It is 101km large in diameter and 4400m deep. Its rim has terraced inner surface, that shows indication of landslips. Central mountain is 1400m high with four separate summits. 
Below and to the left there is Cyrillus crater. It is smaller and older than Teophilus, so this latter one intrudes its rim. The floor of Cyrillus is relatively flat and contains reduced central hill and considerable crater Cyrillus A. Slightly northeast to its center three rounded mountains rise to about 1000m above the crater floor: Cyrillus Alpha, Delta and Eta. Little below and to the right of these hills there is barely visible Rima Cyrillus.
When you go even lower there is Catherina impact crater. Among these three craters this one is the most ancient. Its rim is heavily worn and irregular and the floor is relatively flat but rugged. 
Small crater to the left of Catherina is Tacitus - its interior surfaces are terraced. Below tacitus to the left there starts the long crater chain called Catena Abulfeda. And Tacitus is also the end of the ridge called Rupes Altai.
To the left and above the picture center there is small, but well defined crater Kant. Its inner walls have higher albedo than surrounding surface. Near by crater center there is low central rise. To the right and above the Kant there is Mons Penck - mountain promontory that has diameter at the base about 30km and climbs up to altitude 4000m. 

At the center of second picture there is Rille Ariadaeus - over 300km long and it is thought to have been formed when a section of the Moon's crust sank down between two parallel fault lines. It is relatively young lunar formation. 
Above the rille there is Julius Caesar - lave flooded crater with low, irregular and heavily worn wall. To the left there is small Sosigenes crater and nearby smaller Sosigenes A crater. Both have almost perfectly round and bowl-like shapes. At the right part of picture in the middle there is Arago crater and above it barely visible dome - Arago Alpha. In the right bottom corner two craters: Ritter and Sabine. There is only a few kilometers valley between these two craters. Once they believed to be volcanic calderas, but eventually it turned out they are impact craters with uplift floor. In the bottom there is old D'Arrest crater, and to the left coming out from shadow two large craters - Agrippa (upper) and Godin (lower). 
To the left of Julius Casear there is Boscovich crater - almost completely eroded away with subsequent impacts. Another old crater remnant is Tempel crater - to the right of Agrippa (bottom and little left from picture center). Its rim has been eroded, indented and reshaped with subsequent impacts and lava flows. 

Clear skies!

Friday, April 4, 2014

The Owl, The Far and The Ugly

Owl Nebula is approximately 8000 years old. The central star of the nebula has brightness about 14 magnitude and mass about 55% solar mass, but is much brighter and its surface temperature is 123000K. The nebula itself holds about 13% solar masses of the matter and its main components are hydrogen, helium, nitrogen, oxygen and suphur. It is typical planetary nebula placed about 2000 light years away.

M108 is very different object - barred spiral galaxy that is seen almost edge-on. This galaxy is knows as quite active one - there are 83 X-ray sources identified there, and there are also a massive black hole in the center. Its mass is estimated to 24 million solar masses. The distance to this galaxy is estimated for 45 million light years, so twenty thousands times far away than Owl Nebula. And this galaxy is really ugly, isn't it?

And what about the Far? There is one in the frame, small galaxy cluster about 800 million light years away, but still you can recognize some spiral structure of the largest member of this cluster. Other ones are apparently pretty small (how small galaxy can be? )

Clear skies!