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Posts Tagged ‘Mark Walters’

Star Cluster NGC 6603 in the M24 Small Sagittarius Star Cloud

There’s nothing particularly impressive or image worthy happening on the Sun at the moment so instead of concentrating on our own star I thought I would show you a few thousand ! The bright knot of stars at the centre of the image below is the open star cluster NGC 6603 buried deep in the heart of the brightest part of the M24 Small Sagittarius Star Cloud, close to the centre of our galaxy.

NGC-6603-stackedalt

NGC 6603 was discovered by John Herschel around 1825-33 and includes 30 stars with an approximate age of 200 million years. The component stars shine at magnitude 11 or 12 and the larger stars dotted around its location in the foreground are magnitude 6.5 – 7.5. The surrounding star cloud as a whole is aged between 200 and 600 million years old. Lets take a closer look at the NGC 6603 cluster………

NGC 6603 cropped There’s a lovely chain of stars in the cluster heading towards the top right of centre.

Image taken 28/3/15 4.56am New Mexico time 10.56am UT on iTelescope T3 (Tak TOA 150, SBIG ST-8300C) RA: 18h 18m 24.1s DEC: -18° 24′ 00″ (J2000)

Chasing Comet C/2014 Q2 Lovejoy at dusk in moonlight – not recommended !

March 29, 2015 Leave a comment

Having somehow completely missed all of the best opportunities to image Comet Lovejoy I thought it was time to try this before the comet disappears below the horizon at dusk and becomes truly impossible to photograph.

To do that I needed time on the iTelescope T20 over in New Mexico. The problem is that I only had a 30 minute maximum window of opportunity to capture the data in 58% moonlight just after the sun had set and with the telescope rapidly approaching its low altitude limit of 25 degrees above the horizon ! In addition, as it was impossible to reserve time 2 hours before using the telescope, I had to run the gauntlet of someone else starting up a short random imaging session on the same telescope before I could get the session parameters set up and sent to the server. In the end I managed to run off two 5 minute exposures in black and white, but the following colour RGB session failed as I hit the telescopes altitude limit before the session was complete – aaargh ! The light from the moon and remaining faint daylight had  a pretty shocking effect on the raw .FITS files when I opened them up. There was a huge grey mist-like gradient across the images and numerous passing aircraft trails too due to the wide view provided by the Tak 106 telescope. Just take a look at this raw image below to see what I mean – this is what most astrophotographers don’t show you !

Before-processingAbove: Raw image before cleaning up – messy! Note the very long comet tail though

Now for the processed images which I am pretty happy with given the problems mentioned above. A good example of how to rescue things from a bad situation………

Lovejoy-wideWide view of comet Lovejoy after processing showing the long extended tail

Lovejoy4Detailed view of the coma and tail of comet Lovejoy

Lovejoy is fading in brightness from its maximum magnitude of 3.7 at perihelion in mid January to 6.8 now, but it is still visible with binoculars so take a look.  It was discovered by Terry Lovejoy in August 2014 and is currently travelling back out of the Solar System between the constellations Cassiopeia and Cepheus low in the north.

Lovejoy orbital pathCurrent orbital path out of the Solar System of comet Lovejoy (light blue line)

Images taken 28/3/15 8:30 am New Mexico time on iTelescope T20  Takahashi FSQ-ED 106, Camera  SBIG STL-11000M. 2 x300 sec, Bin 1, Luminance. RA: 01h 23m 18.0s DEC: 64° 40′ 09″ (J2000). Processed in MaxIm DL5, DeepSkyStacker 3, Photoshop CS2.

Supernova SN2015F in Galaxy NGC 2442 28-3-15

March 28, 2015 Leave a comment

ngc-2442-stacked4

I fancied a change of scenery after all of the recent solar activity of various sorts and ventured south of the equator this time. As many of you who read this blog will know I often like to take images of supernovae which briefly appear in distant galaxies and the current brightest supernova is SN2015F. I reserved some time at the iTelescope Siding Spring observatory in Australia and used their half metre T31 Planewave telescope to capture this image.

Supernova 2015F was discovered on 9/3/15 by Berto Monard. It is a Type Ia currently at magnitude 13.3 and is located within the intermediate spiral galaxy NGC 2442, more commonly known as the Meathook Galaxy, in the constellation Volans (southern hemisphere). The Meathook Galaxy lies 50 million light years away and was first discovered by John Herschel.

Type Ia supernovae are fairly common in galaxies with old star populations and are really useful for determining distances between objects and even the age of the universe. Type Ia’s are the result of a white dwarf star exploding in a binary star system due to complex gravitational interactions between the white dwarf and a much larger companion star. The white dwarf grows to approximately 1.4 times the size of the Sun and then becomes unstable and explodes, destroying the star completely.

Imaged 28/3/15 10.28pm Australia time (11.28am UTC) on iTelescope T31 CDK 500mm Planewave with FLI-PL09000 camera. 3×300 sec, Bin 1, Luminance, RA: 07h 36m 18.0s DEC: -69° 31′ 59″ (J2000). Processed in MaxImDL5, DeepSkyStacker 3 and Photoshop CS2.

Aurora over Mid Wales 17th March 2015

March 18, 2015 Leave a comment

DSC02490-3webI was flicking through my twitter feed 9pm last night when I noticed a rash of aurora alerts and aurora images being posted from people around the north of the UK and even down as far as Norfolk ! I checked Spaceweather and a KP8 storm was predicted with aurora potentially naked eye visible across the UK.

Collecting the Sony RX100 camera and a tripod I headed up the Montgomeryshire Canal so that I could get a wide view looking north. And there I stood in increasingly freezing temperatures for two hours seeing absolutely nothing. Well that’s not strictly true, I could see the light pollution above Oswestry, the approaching headlight reflections in light fog of cars coming down the Four Crosses bypass and the occasional passenger jet or satellite. It was 10.54pm and I was about to give up when I noticed something odd about the sky above the light pollution layer. To the naked eye all I could see was a brighter ghostly band of white light above the light pollution and above that were some amazing faint white spires. I put the camera on f1.8 with an 8 second exposure at ISO 1600 and to my utter astonishment the brightly colored aurora appeared in front of me. The bright green and magenta colors and fine structural detail in the spires came out quite well in the photographs.  The light show lasted just 7 minutes until 11.01pm and then faded back to the north. I stayed out until 12.40pm with my wife hoping to see them again, but it was not to be.

This is the first time I have seen the aurora and it was a real treat to see them from home on such a rare occasion.

DSC02490-2-web

Categories: Aurora Tags: , , , ,

New Supernova SN 2014J in Galaxy M82

January 26, 2014 Leave a comment

Discovered on 21/1/14 by Steve J. Fossey when it was at magnitude 11.7 SN 2014J has continued to brighten to about magnitude 10.7. This supernova is a Type Ia-HV (high-velocity) with exploded gases escaping at about 12,400 miles per second. The progenitor star was a white dwarf made of carbon and oxygen, which have now fused into silicon during the explosion.

This is the closest and brightest supernova for the last 21 years and will be visible in 3″ and 4″ amateur telescopes.

Images taken 26/1/14 between 5.23 to 6.07 am New Mexico time on iTelescope T11 (black and white ) and T3 (colour) RA: 09h 55m 54.1s DEC: 69° 40′ 59″ (J2000)

Click on images to enlarge….

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