A Year of Astronomy from the Pinetree Observatory

Some of you may have seen my garden thread, where I built an observatory and garden railway feature. Since the observatory was completed in 2022, I haven't used it as much as I wanted to, partly due to poor weather and partly as a result of being too tired from all the other garden landscaping!

Across 2024, I have managed to get out a bit and as @JennyJB mentioned in that thread that she'd be interested in seeing some pictures, I thought I'd post up a selection from this year.

I'll start on the 28th of February with some pictures of the Sun. I have three different wavelengths of light I use on the Sun, each showing different features and detail. They are Solar Continuum, which uses the 540 nanometre wavelength in the green part of the spectrum, Calcium K Line which is 390~398nm wavelength and Hydrogen-Alpha at 0.75 Angstroms ( 0.75 Angstroms = 0.075 Nanometres ). The camera is greyscale, so any colour you see in the images is false colour added to help show detail.

Solar Continuum at 600mm focal length.


Calcium K Line at 600mm focal length.


Hydrogen-Alpha at 350mm focal length.


Here's some close ups of Active Region AR3590, in the three different wavelengths of light. The first two images were from the same telescope, but with different filters. The third image is from the Hydrogen-Alpha scope which is shorter, so the image is smaller than the first two, but is of the same region.

In the first two pictures, the general background of the solar surface is split up into small convection cells. Each of those cells is around the size of Texas. To help put it all into perspective, I've added a picture of the Earth to give scale to the Sun Spots.

 

Thanks @ArmyAirForce !
I vaguely remember the different wavelengths of emission/absorption lines (calcium K, H alpha etc) from an Open University course that I did a while back. Aren't iron emission wavelengths sometimes used for solar imaging as well? Or is my brain off in cloud cuckoo land today?

 

Professional and space based observatories watch the Sun in all sorts of different wavelengths, each showing different details and characteristics. I think Nickle Iron is used for a Magnetogram to catch the magnetic field.

Next up is the Moon from the 19th of April. This image is a mosaic, made from six captures at a longer focal length, giving a more magnified image. This picture is over 5,000 x 4,000 pixels in size ( direct link here - https://www.sacarr.co.uk/astro/moon/240419moon1.jpg ).



Due to the often fast flowing atmosphere on Earth, I don't take single images of solar system targets like the Moon, but instead shoot a video. Software then breaks down the video into single frames, looking for those which are clear and sharp. I select a percentage to use and the software stacks the best percentage together to give a cleaner, less noisy image. I then adjust the brightness, contrast and sharpen to enhance the details to give a final image. The smallest craters that can be seen when viewed at full size are 2 miles diameter.

 

In addition to doing more solar imaging in June, on the 28th, there was a display of Noctilucent clouds. I believe the name comes from the German language and translates as Night Shining clouds. Noctilucent clouds are composed of tiny crystals of water ice up to 100 nm in diameter and exist at a height of about 249,000 to 279,000 ft, higher than any other clouds in Earth's atmosphere. These were taken on my phone from the front of the house.

 

I was away at a 1940s event at the start of May and missed the large Aurora event that so many people were sharing pictures of. However, I got an aurora alert for the evening of the 13th of August, so took the family out to look for a darker sky away from home.

We didn't see anything and just as Lynne started to drive home, I said to stop. I caught some faint grey lines out of the corner of my eye. Barely visible to the eye, some 30 second DSLR images caught the aurora colours.



This image also captured a couple of satellite trails at the top centre of the image.


A couple of days later on the 15th, I had a go at catching the planet Saturn. Even at 11:30pm, it had only risen to 16° above the horizon, so not the best place to image it. I would have got better results had I waited until it was due South, where it would have been 28°, but that would have meant staying up until 2:50am. I did manage to catch it was five of its moons.

The position of Saturn in its orbit means that we are now seeing its ring system almost edge on. For comparison, the second Saturn image was taken in 2014.


11th March 2014

 

The aurora were back on the 10th of October, capturing three colours spread across a wide area of the sky from home.

 

Four days later on the 14th, the cloudy sky cleared around sun set, allowing me to find and photograph Comet 2023 A3 Tsuchinshan-ATLAS.

Initially the sky was too bright. I was looking in the right direction, but couldn't see it. Finally I spotted it on a couple of longer exposures, then repositioned the camera for some different compositions.







It clouded over again for the next few days, then cleared on the 19th, but by that time, the comet had faded quite a lot.

 

I did quite a bit of hand-held imaging of Sun sets and Moon rises across October and November, plus some more close up solar imaging, but I'm trying not to show similar things, so will move on to December.

On the 19th, it was a clear, but very cold night. I was set up by 6:30pm and managed one quick capture of Venus before it went behind a tree. It was only 6° above the horizon, so the atmosphere distorted it quite a bit. The capture did show the little over half phase.



This picture is from four years ago when Venus was much higher in the sky. Using a combination of Infra-red and Ultra-violet filters, I was able to catch cloud details that are otherwise invisible to the naked eye.

 

After Venus, I moved on to Saturn, which was only 23° above the horizon. This is still far from ideal, being amongst the light and dust pollution and looking through more thickness of atmosphere than if it were higher in the sky. Three of its moons are visible.



Jupiter was at 33° at 6:56pm when I started the first capture. The dark dot on the left side is the shadow of the moon Io, crossing the disc of Jupiter. There's a slightly brighter dot just to the right, which is Io.



I continued watching Jupiter for the next couple of hours, tracking the moon and shadow as they slowly moved over the face of Jupiter. The giant moon Ganymede was also in shot. It's tricky to expose the moon, without over exposing the planet.



Io has now cleared the disc, while its shadow hasn't quite left yet.



Jupiter was around 50° by the end of the transit. The additional altitude meant that later images were clearer and had more detail. These was shot at 3 metres focal length.

 

After a coffee break to warm up inside ( it was 0°C at the observatory ), Mars had risen high enough to give it a go. It was at 35° for this first colour capture. The polar ice cap is visible, along with some surface features. At the time of the pictures, Mars was 104,814,263 km from Earth. On the 12th of January, Mars will be at its closest approach, at 96,084,297 km from Earth.



The second capture was in Infra-red at the 742 nanometre wavelength, which often passes through the atmosphere better than other colours.

 

To finish the evening of the 19th, I turned the scope on the Moon which had now risen. That was at 22° above the horizon. It was a bit too low for good close up images, but fine for lower focal lengths.

The first few captures were at 3 metres focal length, but due to the low height of the Moon and the thicker atmosphere, the detail was a bit soft.

Plato crater and Vallis Alpes


Clavius Crater


Mons Bradley


The first full disc Moon capture is a mosaic of five images, shot at 1 metre focal length ( the fullsize 5,500 x 4,125 pixel image link - https://www.sacarr.co.uk/astro/moon/241219moon2.jpg ).



The last shot of the night was on a smaller telescope, which had a 600mm focal length, allowing the whole of the Moon to fit the camera sensor.



I haven't managed any deep sky nebulae or galaxy images this year, as it's much more complex and time taking than planetary imaging and I just haven't had the energy.

I'll try to remember to add more images if I get out during the rest of the Winter. However, as we've past the 21st of December, the nights are getting shorter again, marching out of astronomy season and back into military vehicle and gardening season!

 

What wonderful passion you have, way-way-way off the beaten track … and what beautiful pictures you take !