Comet Neowise 12-7-20

C/2020 F3 (NEOWISE) was discovered on March 27th 2020 by the NEOWISE space telescope. It passed closest to the Sun on July 3rd 2020 and will be closest to Earth on July 23rd. It is currently magnitude +1 and easily seen with the naked eye low on the northern horizon just above roof tops from 1.45 am onwards until sunrise. It steadily climbs towards the NE from 2am – 3am but the sky also gets brighter so for naked eye viewing earlier is better.

Comet NEOWISE 12/7/20 2.13am ISO 800, f2.8, 1 x 8 seconds, 70mm, Sony RX100 MkIV

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Venus in the Pleiades Cluster

A bit cloudy for photos tonight but it was nice to briefly see Venus travelling past the Pleiades star cluster (M45). 9.30pm. Sony RX100 IV, f2.8, 4 sec, ISO 1600, 70mm

Comet C/2019 Y4 (Atlas) – now in colour!

I popped back to iTelescope T14 remotely yesterday and took a series of luminance and RGB exposures of Comet C/2019 Y4 as it passess through the constellation Camelopardis. I wanted to try out the Astro Pixel Processor software with LRGB combining for the first time having run through the excellent tutorial by Christian Sasse. I think there were some stages in the processing workflow where I missed a few tricks, but overall I was quite pleased with the final product for a first attempt.

iTelescope T14, Tak106, SBIG Universal camera. Mayhill, New Mexico 31/3/20 00:15-00:45 UTC-6. 10 x 60 sec Lum, 2 x 60 sec each R,G,B Bin 1. Processed in Astro Pixel Processor and Photoshop Elements 2018

Astro Pixel Processor – Learning about LRGB processing

I have been used to imaging in the past with RGB colour cameras, but now that the iTelescope remote telescope network has switched completely to cameras fitted with the more sensitive mono sensors and RGB filters I am forced to learn a new method of processing to combine RGB exposures with the luminance exposures. This is a good skill to learn as the images will potentially be more detailed with less noise and this is how the vast majority of astro imaging is done.

I saw the recommendation for the Astro Pixel Processor software on the iTelescope website and it seems to be well respected with good results so I thought I would give it a go on the free trial offer. Astro Pixel Processor can be found here https://www.astropixelprocessor.com/ There is an excellent video tutorial taking you through all steps to process an LRGB image of the Small Magellanic Cloud NGC292 here LRGB Tutorial The data was kindly made available by Christian Sasse,

The tutorial is in 9 parts and easy to follow although some of the menu items have changed in the latest update to those visible in the tutorial and there are additional options when loading files that are different too like the panel asking you about which session you want to use. I just went with the defaults and dropped all files into Session 1 every time and everything worked out fine.

The staged workflow is easy to follow and the software is actually very good at auto processing many of the early stages with minimal input. The fun really starts in the Tools section after you have combined the RGB image following calibration, registration and integration. Here you can calibrate star colours, remove light pollution and crop the image to suit. Then you can switch to the Preview section on the right and follow through the comprehensive Digital Development Process (DDP) including adjustment of the black/white point, saturation, sharpness, contrast, select the correct histogram stretch and much more. The changes are visible in real-time on the screen and when you get to a result you are happy with just save the stretched image as a Tiff or Jpeg.

I was pretty pleased with the results for a first ever process of LRGB data and look forward to using the software for comet and supernova imagery.

Small Magellanic Cloud processed in Astro Pixel Processor using data by Christian Sasse. Star Spikes added with Starspikes Pro in Photoshop Elements.

Comet C/2019 Y4 (Atlas)

Comet C/2019 Y4 (Atlas) is fast approaching for a meltdown rendezvous with the Sun at its closest approach around 31st May 2019 when it may brighten to magnitude -1 and will be visible to the naked eye. It is currently magnitude 8 and passing between the constellations Ursa Major and Camelopardis. It may be the brightest comet we have seen for a while and is worth keeping track of. At the moment you can only see it with a larger telescope and some imaging to bring out the detail in the bright surrounding coma and short tail.

Above: Comet C/2019 Y4 (Atlas) at centre of photo passing the 5.3 magnitude G7IIb star HIP40215 (top right of comet) in Ursa Major. The faint comet tail is to the bottom right. Image taken 23.45-12.00 28/3/19 Mayhill, New Mexico, USA UTC -6. T14 Tak FSQ ED 106, SBIG Universal camera 7×60 seconds Lum. Processed in Deepskystacker and Photoshop Elements with Astro Tools

Above: A view of the projected path of Comet C/2019 Y4 through the Solar System in the next few months.

Kaguya Lunar Atlas

I first bought a copy of this book back in 2011 when it was published. Since then, and thanks largely to the accompanying text, it has been a constant companion in my lunar library. The book presents good quality HDTV images from the camera onboard the SELENE (more commonly known by its Japanese nickname Kaguya ) orbiter. Kaguya was launched in September 2007 and after a number of successful orbits it was deliberately crashed into the lunar surface in June 2009. It’s two 2.2 megapixel CCD HDTV cameras, one wide-angle and one telephoto, along with a terrain and multi-band imager, sent back some fantastic high resolution images. The book uses the HDTV images along with descriptive text of the features to give you a good primer on the typical features you will see and explains their formation and origins. The book openly encourages you to interpret lunar features for yourself as you progress through the pages and you will find that this does quickly become possible.

The book is now out of print and secondhand copies are extremely expensive (£80 + on Amazon) . You can occasionally find some reasonably priced editions at the AddALL used and out of print books search here AddALL Books Search where I have seen copies going for £20 – £25. If you see one, snap it up, this is a fantastic book for the lunar enthusiast/planetary geologist.

Noctilucent Clouds from Mull of Galloway Lighthouse.

We are on holiday staying at one of the light-keeper’s cottages at the Mull of Galloway lighthouse at the moment. The views here are extensive all around on the headland and the dark sky quality is very high, well minus the bright blue beam of the new LED light that has just been installed in the lighthouse it is! At midnight I took the dog out for a walk and was greeted with panoramic noctilucent clouds spanning the northern horizon – the best view I have ever had. They changed constantly with bands and swirls, ripples and waves. I stood out there on top of the prehistoric burial mound above the lighthouse compound for two hours in an increasingly chilly wind, but it was well worth it !

Its my birthday! And there are Noctilucent Clouds!

Had a great day out in the hills above Rhayader today and was about to head for bed when I thought I would look out of the window and just check if there are any noctilucent clouds as there has been reports in the UK on twitter from quite low latitudes. Much to my amazement there was a fabulous show going on at 11pm through to midnight. Lots of ripples and wave details in the upper levels !

Dark Skies of the Tywi Valley, Carmarthenshire

We stayed at a remote cottage in the Tywi Valley north west of Rhandirmwyn in Carmarthenshire for a week and I had a couple of opportunities to spend some time under the dark skies available here. To the naked eye there is no light pollution at all within the Tywi valley and the Milky Way is easily seen when your eyesight is dark adapted. The higher sensitivity of the camera sensor picks up some light glow from Rhandirmwyn village and a larger amount from the town of Llandovery, which lies some 10km distant. The area is well known for dark skies with a couple of sites recommended here Dark Sky Discovery Sites UK including the YHA hostels at Ty’n-y-cornel and Dolgoch located to the north of the Llyn Brianne reservoir.

Here are some photos taken from the cottage on clear, but occasionally cloudy, nights with the Fuji X100s at 28mm, F2, ISO 6400, 15 – 25 second exposures.

Above: Looking south through thin cloud with some light pollution from Rhandirmwyn and Llandovery evident. Delphinus (upper right edge) with the head of Pegasus (centre) and parts of Aquarius.

Above: Looking north east at the constellations Cassiopeia (top) and Perseus (centre) with the bright star Capella in Auriga near the bottom of the photo

Above: Looking west towards the Allt Ty’n-y-ddol ridge with Ursa Major (the Plough) just above the dark ridge line. The Pole Star – Polaris (top right) and Ursa Minor and Draco to the left of Polaris.

 

 

Mercury Transit of the Sun 9-5-16

Well I consider myself extremely lucky to have seen this event as the cloud cover was horrendous for most of the day. These images were actually taken through the thinnest of that cloud between 15:30 – 16:50 and the quality of the images is pretty dire, but nonetheless a good record of how I saw things from the back garden. I was amazed at just how small the planet looks against the Sun, not much bigger than the sunspot group nearby.

The transit began at 12.12 BST, and ends at 19.42 BST so you have a few minutes left to see it in the UK ! Mercury is 4,800 km in diameter and orbits the Sun in 88 days. Transits of mercury are fairly rare events with 13 taking place every century in November or May.

The Sun in CaK light showing sunspot group 2542 to the right of centre and Mercury to the left of centre

The Sun in Hydrogen Alpha light showing curving filaments and Mercury top left of centre

The Hydrogen Alpha disk showing Mercury upper left of centre