Session 39 – Beautiful Bank Holiday

Monday 7th May 2018 – 22:12-22:28

The Bank Holiday had had amazing weather, with cloudless skies the entire weekend.  Before it ended, I opted to have a quick observing session, to take advantage of the beautiful weather.  Unfortunately it was a school night, so it had to be brief!

Jupiter is rising earlier and earlier each day, and so the king of the planets was the obvious first target.  Give how bright it is in the south eastern sky at the moment, no alignment was required.  If you look towards the south east at around 22:00 onwards, you can’t miss it!  All four Galilean moons and the equatorial cloud belts were visible, and it was very bright through the telescope.  Tomorrow marks the time for this year when Jupiter reaches opposition – ie it is nearest Earth and is brightest, so tonight was one of the best opportunities to observe it!

I wanted some variety tonight, so continued with some deep sky objects, after first aligning on Arcturus and Spica.  Now that I’m more familiar with the night sky, I have decided to choose my own alignment stars, which is a good improvement.

After the alignment, I slewed to M5, a globular cluster.  It appeared pretty bright, and gave a great view of what a globular cluster looks like.  Definitely worth a look if you’ve not seen it!

Moving onto open clusters, the centre of the Beehive Cluster – M44 was next.  This is a large open cluster, that is significantly larger than the field of view of my telescope, so although it is impossible to see it in its entirety simultaneously, the centre gives a wonderful and enjoyable view.

With the night drawing in, the session ended after M44, but although it was short, it was still very enjoyable with three stunning objects seen!


Session 38 – Venus and Jupiter

Friday 4th May 2018 – 21:00-22:53

The weather today was amazing, and this evening’s sky was crystal clear.  I headed out before it got dark to have a quick look at Venus.  I pointed the telescope straight at it, which was lucky, as it was just disappearing behind the house.  I enjoyed the sight, all 30 seconds of it!

Next I aligned on Arcturus and Pollux, before taking a quick look at the other half of Gemini, the double star Castor.  Both stars were bright and the separation was clear.  After this, I spent some time just sitting on the chair, looking at the sky with just my eyes.  It was a refreshing and enjoyable sight, especially with the light summer breeze.

That sky continued to darken, and I decided to spend some time observing a few globular clusters.  It has been quite a while since I’ve dedicated some time to looking at these objects, and there were several to observe, so it made a good change.  Overall, I saw M3, M5 and M53 (the latter two are two new Messier objects I can now tick off my Messier list).  They were all faint and diffuse, as globular clusters often appear, with M53 being the faintest.

I moved the tripod, realigned on Arcturus and Capella, and slewed to Jupiter, which was just rising in the East.  The cloud belts were highly visible, with the two deep red ones (the Northern and Southern Equatorial Belts) very obvious.


Jupiter, with the two red cloud belts visible

Having seen the cloud belts clearer than I’d ever seen them before, the next objective was to find the Great Red Spot.  It was supposed to be transiting the planet around this time, and after a while, I was able to see it.

Imaging the spot proved significantly more challenging, but I have managed to get a picture of it.  It took a lot of processing afterwards, and the result isn’t perfect, but you are able to just about make out the GRS at the bottom centre of Jupiter in this following picture.


The Great Red Spot can be seen along the bottom red cloud belt.  Three Galilean moons are also visible in this image (L-R: Europa, Io, Callisto)

Having spent a long time looking at Jupiter, and the planet is currently residing in Libra, I decided to observe three of Libra’s main stars.  Zubenelgenubi was the first, and is a double star.  Zubeneschamali came next, and it had a white/yellow hue.  The third and final star was Zubenelhakrabi, which has two gas giant planets orbiting it.

Having had a successful couple of hours, I ended the session.

Session 37 – Filtered Full Moon

Monday 30th April 2018 – 22:30-22:48

The weather today had been appalling, but mercifully there was a break in the clouds tonight, revealing a beautiful full moon, very close to Jupiter.  As my moon filter had arrived, the current full moon seemed to be the perfect time to test it out!

I set up outside, and didn’t do an alignment.  Both the moon and Jupiter are very easy naked eye objects, and as such, I could easily slew to them myself manually.

I started off by looking at the moon without the filter, and as expected, it was very bright.  Attaching the filter made a big difference, and the moon was comfortable to view.  Additionally, it seemed to bring out the definition of the craters along the (very slight) terminator rather nicely.  I repeated the exercise with the 9.7mm eyepiece, and the effect worked well with that as well.  I spent a while looking at the moon, and in particular found some interesting craters along the edge (which turned out to be La Pérouse and Ansgarius).

Having spent a good while exploring and admiring the moon, I decided to spend a few minutes looking at Jupiter.  All four Galilean moons were visible, and cloud belts on the planet were very easy to spot tonight.  Unfortunately the Great Red Spot was not visible, but hopefully soon I’ll be able to see it!

Sadly, the clouds came in at this point, and so I had to go inside, but overall a highly successful session, especially with the test of the new moon filter against the full moon!

Observatory Upgrade 2 – Moon Filter

The second upgrade has arrived, and it is the moon filter I have said several times I needed to get.  It reduced the amount of light that passes into the eyepiece, evenly across the visible spectrum.  The idea is that it reduces the brightness of the full moon, which can be painful on the eye when observing it through a telescope, as it is pretty bright!


The filter in its box

One thing it’s worth noting is that the filter screws in to the bottom of the eyepiece (ie the end that goes into the telescope, not the end you look through).  If you haven’t used a filter before (like me), it is not necessarily intuitive!


The filter attached to the eyepiece

Session 36 – Kemble’s Cascade

Wednesday 25th April 2018 – 22:04-23:10

I’d recently come across an interesting sounding asterism known as Kemble’s Cascade and decided that it warranted some telescope time. It is a chain of stars, situated in the far northern constellation of Camelopardalis – the Giraffe. This constellation is quite faint and does not have many objects of interest, so it was a pleasant surprise to find something within it that intrigued me. Located at one end of the cascade lies NGC 1502 – a small open cluster, which makes locating it much easier.

Unfortunately for me, my observing site has a tree to the north, and as such this part of the sky is always difficult to observe. I opted to set up the telescope on the front patio by the house, which I seldom do. After aligning on Arcturus and Regulus, I slewed to the cascade, and discovered it was now behind the house! The telescope batteries had not been changed for quite some time, and it was running dangerously low on power. As such I decided to take the telescope back inside, replace the batteries, and set up once more in the usual spot, hoping that the tree would not be in the way.

Luckily for me, the tree did not impede my observation, and I found the open cluster (NGC 1502) at one end of the asterism (after realigning, this time on Arcturus and Spica). The cluster itself was quite compact and small, and had two bright stars that looked a little like eyes. It was very nice, and a good signpost for Kemble’s Cascade.

The cascade itself is quite large, so to observe it all I had to slew the telescope. However it was nice to see, and well worth the challenging set up (although it wouldn’t fit in the eyepiece all at once, so a focal reducer and/or imaging it as a mosaic would make it more spectacular).


NGC 1502 and Kemble’s Cascade (outlined in grey) – screenshot from Starry Night Pro

Once I had spent some time observing this, the next target was Jupiter, which was just rising.

I had a good view of the planet, and all four of the Galilean moons were visible.  I found it quite difficult to get it in focus with the 9.7mm eyepiece, but it looked good after a while.  There were cloud belts visible, although I couldn’t see the Great Red Spot (but that may have been because it was on the side of the planet facing away from Earth).

One issue with the Great Red Spot is that it drifts around the planet and is not in a fixed position.  As such its position as simulated in Starry Night is almost certainly incorrect.  Fortunately this has been thought of by the developers, and its position can easily be changed by altering a number in a text file.  Since this observing session, I have found a website that tracks the GRS’ longitude, and it appears to drift fairly predictably, making regular updates to the position in Starry Night fairly straightforward (and therefore enabling me to predict when I ought to be able to see it)!  There is also a good website that tells you when the GRS should be transiting the face of Jupiter.

After I’d spent some time observing Jupiter, I decided to have a look at the moon before heading indoors.  The wind was starting to pick up at this point, and I didn’t want to risk the telescope blowing over.  The moon was very bright, even though it is still waxing.  I have now finally ordered a moon filter, so the brightness of the moon will be less of a problem in the future!

I saw a couple of interesting looking craters along the terminator, which I later identified as Hainzel and Mee.  I also saw Clavius.  I took a few photos with my phone through the eyepiece, and although the quality isn’t great, you can clearly see Clavius, and the other two craters too.


Clavius is visible towards the bottom left of the image, while Hainzel and Mee are located about halfway up along the terminator

Having had a long and successful session (in spite of the issues at the beginning), I went inside and ended the session.

Observatory Logo

Every good observatory needs a logo, and this one is no exception.  As such, I have designed a logo for the West Addiscombe Observatory, and going forward, it’ll feature on the site!

I’ve taken the three initials of the observatory (WAO) and found stars that spell out those shapes.  Respectively, these are the constellation of Cassiopeia, the Jewel Box Cluster (alas invisible from the northern hemisphere) and the constellation of Auriga.  The colours of the stars in the initials reflect the spectral types of the stars that make up the shapes.  The font I have chosen is a digital version of the Johnston font that is so familiar to all Londoners – the “tube”/TfL font.  Given that the observatory is in London, this font fits perfectly.

So, here’s the logo in all its glory!: