Photo courtesy of Rod Trevaskus from Middletown in Powys who took this image of the Milky Way on the 12th August, complete with two meteors! Click to enlarge…
Last Monday night (12th August) was the peak of the Perseid meteor shower when the dust trail left over from the passage of Comet Swift-Tuttle crosses Earth’s orbit and the debris, reaching speeds of up to 132,000 mph, burns up in our atmosphere. It is the most impressive of the annual meteor showers with the highest number of bright fireballs (meteors reaching a brightness of magnitude -3 or brighter at the zenith) and at it’s peak, in good dark-sky conditions, you can expect to see up to 120 meteors per hour across the whole sky.
We had almost forgotten the shower here in the early evening as the weather had been very cloudy, there was a low quarter phase moon in the west and the prospects for good visibility looked poor. The inclement weather, combined with the need to get up early for work the next day, made us rather apathetic about the whole event. Fortunately my wife poked her head out the back door just before we headed off to bed and I heard that familiar little gasp of awe as she called me out to look at the amazing clear sky. The clarity of the sky on Monday night was astounding here, one of those really rare nights when the stars are rock steady with no furious twinkling going on. The Milky Way was so bright overhead that it looked like moonlit cloud passing over. Within a minute we had seen our first small Perseid flash by and decided to stay out for a while. The Ikea Poang chairs were brought out, which lend themselves perfectly to visual astronomy as they are low and gently reclined with good back and neck support. We covered up in light duvet jackets and a fleece or sleeping bag over the legs – we were all set for the show.
In the end we were out there for just over two and half hours from 10.30 -1.10 with a good dark view of the western sky and saw a total of 60 meteors. Most were faint and white with a yellowish tinge, but some were greenish and one large fireball heading down through the constellation Hercules was quite magenta in colour, with a long persistent glowing tail burnt onto our retina’s which lasted a few seconds. We had a nice bright pass of the International Space Station around 11pm and there were two really bright iridium flares from the Iridium telecoms satellites passing over. We had at least three bright fireballs in that time and something really big flashed over in the north, out of our direct line of view, which briefly lit up the thin cloud cover building up at that time. We both came in buzzing from everything we had seen and that excitement lasted right through to the next day.
With all of our expensive modern equipment in amateur astronomy these days it is comforting to know that the simplest and most companionable form of visual astronomy can still give you that sense of wonder and buzz of excitement. It was one of those unplanned events in our life that we will always remember and cherish.
This new nova was discovered by Koichi Itagaki (Teppo-cho, Yamagata, Japan) on August 14th at a spectacularly bright magnitude 6.8 ! The nova appears to have brightened even more throughout today (15th) to a possible maximum magnitude of 5.7 – 5.5, which would make it naked eye visible and clearly visible in binoculars. As most novae rarely reach magnitudes greater than 12 this is a rare event. The nova is the bright star at the centre of the image below.
The spectrum of Nova Delphini 2013 suggests this is a classical nova ie. an interacting binary star system in which one star is a dense, hot white dwarf. Material from a cool, giant companion star falls onto the surface of the white dwarf, building up until it triggers a thermonuclear event. The drastic increase in brightness and an expanding shell of debris is the result. Classical novae do not result in an entirely destroyed star, but are instead believed to recur when the flow of material onto the white dwarf resumes and produces another outburst. The speed of material being ejected from this supernova has been calculated at around 1,500 miles per second. The progenitor star may have been around 17th magnitude prior to the outburst.
UPDATE 1 16th August – AAVSO observers are now reporting the magnitude of this nova at around 4.4 – 4.5 This will be readily visible to the naked eye although the moon is currently affecting visibility.
UPDATE 2 17th August 12.30am – Just had a look now and it is very easy to find with the naked eye even though there is low moonlight and cloud around. The constellation Sagitta neatly points the way to it. It looks about magnitude 4.8 to me visually when compared with the nearby star HIP 101867. This seems to match current AAVSO observations which show the nova has started to fade back from a peak 4.5 to mag 4.8
UPDATE 3 18th August – According to AAVSO observer reports the magnitude of the nova appears to have stabilized around mag 5.0 (updated chart below) for now. The peak magnitude of 4.3 was reached on the 16th 16.45 UT. A fast decline was predicted thereafter of about 1 magnitude per day, but this prediction has now been revised. The progenitor star appears to have been mag 16.9 before the outburst.
There are some useful finder charts here for visual observing http://www.virtualtelescope.eu/wordpress/wp-content/uploads/2013/08/NOvaDel2013_map.jpg and here http://www.virtualtelescope.eu/wordpress/wp-content/uploads/2013/08/NovaDel2013_map2.jpg
Image taken 15/8/13 11.43 pm local time on T18 (12.5″ Planewave CDK, KAF-6303E) at Nerpio, Spain. 1 x 60 secs Lum. Processed in Maxim DL5, Photoshop CS2. RA: 20h 23m 30.0s DEC: 20° 46′ 06″ (J2000)
Click image to enlarge:
AAVSO Light Curve:
Supernova 2013ct is a Type Ia discovered by Stu Parker (BOSS – New Zealand) on 10/5/13 when it was at it’s peak magnitude of around 12.2. It has now faded to approx mag 15.4
NGC 428 lies in the constellation Cetus approx. 37 million light years away. The galaxy has a distorted shape perhaps resulting from the collision of two galaxies.
Image taken 12/8/13 4.46 am local observatory time at Nerpio, Spain using remote iTelescope T07 (Planewave 17″ CDK, SBIG STL-11000M ABG). 4 x 300 secs Lum. Processed in Maxim DL5, Adobe Photoshop CS2, DeepSkyStacker 3.3.2
Click image to enlarge:
AAVSO Light Curve:
This Type Ia supernova was discovered on 10/7/13 by the Lick Observatory Supernova Search programme and Kuniaki Goto two weeks before it reached it’s peak brightness of around magnitude 12.7 on 25/7/13. The supernova is currently at magnitude 13.0
NGC 7250 (PGC 68535) lies some 55 million light years away and is a rather small object which is difficult to image. It was discovered by William Herschel on November 8th 1790 and is classed as a starburst galaxy.
Image taken 6/8/13 4.18 am local observatory time at Nerpio, Spain using remote iTelescope T07 (Planewave 17″ CDK, SBIG STL-11000M ABG). 4 x 300 secs Lum. Processed in Maxim DL5, Adobe Photoshop CS2, DeepSkyStacker 3.3.2 RA 22 18 17.7, Dec +40 33 47
Click image to enlarge:
AAVSO Light Curve:
A new Type IIP supernova was discovered in spiral galaxy M74 in the constellation Pisces by the Lick Observatory Supernova Search on 25th July. It has brightened rapidly to around magnitude 12.4 and is visible in 8″ amateur telescopes, but will show up readily in images taken on lower aperture telescopes of 4-6″ under dark and clear skies.
This star was originally a supergiant about 8x the size of the sun before it ran out of fuel to burn, collapsed due to gravitational forces and then exploded into the bright source of light that we can now see. Besides blasting new heavy elements out into space the supernova may leave behind a neutron star, which is the compressed remnant of the stars original core.
Image taken 4/8/13 4.01am local observatory time at Nerpio, Spain using remote iTelescope T07 (Planewave 17″ CDK, SBIG STL-11000M ABG). 5 x 300 secs Lum. Processed in Maxim DL5, Adobe Photoshop CS2, DeepSkyStacker 3.3.2
AAVSO Light Curve:
It might be a rather warm 23 degrees outside but there’s a lot of cloud around too and the atmosphere is very turbulent, so there was no opportunity for some nice close up images of the large sunspot groups 1785, 1787, 1788. The smaller 1784 group can be seen to the right. The largest sunspot, 1785, has the potential to produce some big flares as it turns to face earth.
This set of images were taken between 12.00-13.00 UTC using the Coronado PST/Coronado CaK/Lunt CaK B1200 on a Vixen 115s. IS DMK41AU02 USB mono video camera. Images processed in Registax 6, Adobe Photoshop Elements 9 and Adobe Lightroom 4.4
Hydrogen Alpha view with filaments
A cloudy and showery day with a few holes in the cloud, one of which allowed me to catch the nice collection of fairly large prominences on view at around 4.30pm. The whole disk is striped with filaments of varying size. The large filament in the south is still clinging on and may make it to the limb in the next couple of days. If it does we will be able to see what it looks like in profile when it turns into a prominence..hopefully a big one!
Images taken with Coronado PST 40mm & DMK41 USB camera. Processed in Registax 6, Adobe Photoshop Elements 9, Adobe Lightroom 4.4
Had a quick look at 10.45 UT this morning and was amazed to see a large extended prominence lifting off from the NW limb (top right) which had disappeared by 11.15 UT. It was extremely faint in the 40mm PST and increasing gain or exposure on the DMK video camera just burnt out the other proms so I had to increase the gamma a lot, which resulted in the colour halo you can see around the disk.
The long filament in the south east quarter (bottom left) appeared to be breaking up with a clear split in the centre.
Images taken with Coronado PST 40mm 10.45-11.00 UT & DMK41 USB camera. Processed in Registax 6, Adobe Photoshop CS2, Adobe Lightroom 4.4
Hydrogen Alpha – Large and faint prominence lifting off top right
Hydrogen Alpha – large filament
It’s been just under a year since I have done any astronomical imaging and even longer since I have imaged the sun, which is a terrible state of affairs ! Last years horrendous weather pretty much killed my enthusiasm with barely any cloudless days and tons of rain. Amazingly we managed to time our holiday with some outstanding clear skies and although the sun is not particularly active today I could not resist a look. It has also been useful to remind myself how to process the images…which still takes ages. Quite pleased I captured some reasonable detail as the atmospheric seeing was pretty turbulent – that’s all down to Registax 6 of course, amazing software.
This set of images were taken between 9-10am UTC using the Coronado PST/Coronado CaK/Lunt CaK B1200 on a Vixen 115s. IS DMK41AU02 USB mono video camera. Images processed in Registax 6, Adobe Photoshop CS2 and Adobe Lightroom 4.4
Hydrogen Alpha Disk with central active region AR1765
Hydrogen Alpha detail of prominences
Calcium K disk
Calcium K surface with AR1765
On May 17th the automated Lick Supernova Search discovered the SN 2012cg supernova in galaxy NGC 4424 in the constellation Virgo. From 18th magnitude it has now brightened to 12.0 and rivals the core of the galaxy for brightness. This exploding star was originally a White Dwarf star equivalent in mass to our own Sun and locked in a binary orbit with a much larger star. It steadily drew matter from this companion star up to a point where it became unstable, collapsed in on itself and exploded, producing what is known as a Type Ia supernova. This spectacular event should be visible in telescopes of 6″ diameter and above.
Image taken Sunday June 11th 00.59 am from Nerpio, Spain with iTelescope T7 Planewave 17″ CDK, SBIG STL-11000M. 300 sec Bin 2. RA: 12h 27m 11.9s DEC: 09° 25′ 01″ (J2000)