What a February!

Since I last posted the rest of February 2017 has happened… there’s not a whole lot more to say than that.

Last month wasn’t quite as bad as last June, but it came perilously close for a while. It’s been cloudy and wet most of the time, but I’ve managed to grab a handful of brief sessions with my smaller scopes.

The fact that the Moon is lovely and high at this time of year has been helpful, though many of the best opportunities have been around New Moon ironically. I say that because there’s a theory that it’s only ever clear when the Moon is in the sky. Admittedly it’s a theory of Deep-Sky observers, but we couldn’t complain about that too much this February.

Still the skies weren’t Deep-Sky clear: the Transparency has been poor due to the high levels of humidity. I believe that the unseasonable warmth is a problem since the moisture hasn’t been forced out of the local atmosphere by sustained freezing temperatures. I’ve often been out observing at midnight at temperatures around 10ºC this winter, and that isn’t normal from a long term historical perspective.

The beautiful twinkling stars are a really bad sign for the observational astronomer. They’re symptomatic of poor Seeing and I suspect the polar Jet stream has been a frequent visitor overhead. When this happens everything is blurred like you’re viewing it at the bottom of a swimming pool. So seeing small features on the Moon or planets is out, and so is splitting tighter double stars.

So I’ve spent February as a bit of an astronomical tourist, just visiting the brighter Messier and NGC objects, the Moon and even Venus as the conditions allowed a half hour of clearish sky. No time for notes or sketches, I’ve considered myself lucky to get the telescope set up before the clouds reappeared.

That’s been OK, though rarely as relaxing as a quick tourist session should be, but it’s also frustrating when my Herschel 400 project has stall, the remaining binocular Messiers are a no-go, and my Variable stars are nearly a month overdue.

Let’s hope for kinder weather in the coming Spring before British Summer Time (BST) arrives and the Solar season is upon us.

Binocular Messiers

You may remember way back in 2014 I wrote about Charles Messier and his list of comet-like objects. I also mentioned that I’d started tracking them down with binoculars, and that was a while ago, so what’s happened since?

I’m still working to my usual leisurely pace, but I’ve collected good observations of 60 of them now. This year would be a great time to finish this project since it’s the 200th anniversary of Charles’ death. The BAA are encouraging observers to complete a Messier Marathon, or at least view all the objects this year. Perhaps I will.

I’m basing my work on the Astronomical League’s Binocular Messiers Program that rate 102 of the 110 to be observable with binoculars. I’ve set the additional challenge to observe as many as possible from my north-west facing back garden. This is one reason why it’s taking so long to complete the project: some objects have a very short window of opportunity. That said, I seem to have managed a couple they don’t think I should be able to see, but I stand by my observations ;-), and having observed 58 from their list have 44 left to go.

Unfortunately most of those are pretty low in the sky from the UK. For example, I snagged M41 in Canis Major a few nights ago as it briefly appeared from behind the row of houses before falling into the trees, and all whilst standing on top of a wall peering through the undergrowth. On the other hand I couldn’t have done that with a telescope! I’m very glad that M41 is big and bright or the Industrial Estate light pollution would have rendered it invisible.

Image Credit: M41 by Digitized Sky Survey (DSS)
Image Credit: M41 taken from the Digitized Sky Survey (DSS) using Aladin Sky Atlas.

The upcoming galaxies of Virgo and Coma Berenices may cause some problems. I’ve observed all the brighter ones and have the trickiest to collect on a night of really good transparency. I’ll have another go at M108 and M109 in Ursa Major on that night too.

Then I’m down to the horizon huggers of Scorpio and Sagittarius below 25° altitude. I can’t think of anywhere around my house that they’re possible. Not the street outside, our front bedroom window, they’d probably be difficult from the roof. So I’ll have to start being mobile to mop the rest up, and perhaps that’s the time for a marathon?

The Scale of Space

On Monday night I took part in one of my Society’s outreach events for local Cub Scouts. These are a challenge. The Cubs meet around 18:00 and go home to bed before most astronomers would be getting started. It’s a very small window for clear skies in the cloudy and damp UK climate.

We aim for around the first quarter Moon since it’s there in the very early evening, it can take light cloud and the kids love to look at the Moon. I’d observed it on each of the previous three nights, which is not a common occurrence in these parts, but on Monday it wasn’t just cloudy, it was pouring with rain.

So what do you do with a 25 Cubs Scouts on a rainy evening in February? Our normal fallback plan involves Stellarium and a talk about the constellations and planets, but it’s a good idea to get the natives moving occasionally or they get restless!

As the Secretary of the Society I’m kinda expected to take a lead in things. So after a quick sky tour of the constellations and how to find the pole star I decided to try something new to me, and I hoped the Cubs: modelling the solar system.

Collectively we marked out the location of each of the major planets in turn on the hall floor – with sticky labels that are easily removed – on a scale that placed Neptune 15 metres from the Sun. I would have liked to include the Kuiper Belt, but the hall wasn’t long enough, and a smaller scale would have seriously crushed the Cubs representing the inner planets!

These Rocky Inner Planets were all squeezed into the first metre with the Gas Giants in the next four and an awfully lot of space for the Ice Giants. I have to admit that I’ve never laid it all out like this before and the spacing was impressive.

The Sun, which Copernicus pointed out, is at the centre of it all and represents most of the mass in the Solar System. It’s about 109 times the diameter of the Earth, but what really fried a few noodles was the discovery that on this linear scale the Sun is only about 5mm in diameter, or the size of a modest peppercorn!

Sun in the palm of my hand
The Sun to scale in the palm of my hand

That makes the mighty Jupiter around 0.5mm in diameter. I couldn’t find a spice in my cupboard that was small enough for this, and the other planets will be virtually invisible, like fine dust.

It makes you appreciate why it takes so long to travel between the planets. Interplanetary exploration involves a lot of waiting.

My Variables Stars

As a follow up to the post on starting out observing variable stars I thought I’d talk about my journey.

I started variable star observing about four years ago with the naked eye and the 10-Star tutorial. I soon moved on to binocular variables, to which I’ve added a smattering of telescopic Mira variables now.

As you can see below, fuelled with enthusiasm soon clocked up 200, receiving a certificate from the AAVSO for my first 100, which was unexpected. Then the observation rate started to drop for various reasons including the appalling weather, British summer time (these two are often linked), and the pursuit of other astronomical interests. It stalled drastically after the first 600.

120 day binned cumulative variable star observations
My variable star observation count up to 19 January 2017.

Well at the end of 2016, I decided it was time to pick up the slack and at least push through the 1000 observations barrier, which I did on 5 October 2016. At the time I generated the chart for this post I was handful short of the 1100 observation mark, but another clear night has put me well over the top.

Choosing my variable stars

I’ve got a telescopic aperture limit of 6 inches and a relatively light polluted site so those exciting, but faint, cataclysmic variables are off the menu for me. Eclipsing binaries are fine, but the most valuable observations of these are CCD photometric these days: visual observers need not apply. Most of my efforts are aimed at Long Period Variables (LPVs) with a few other types thrown in for variety, and delta Cephei for nostalgia.

I choose variables to suit the magnitude range of my equipment and by constellation. The latter allows me to concentrate my effort in a smaller area of the sky: it’s an efficiency thing. I also have favourite constellations: it’s a personal thing, and possibly pragmatic too 😉

My back garden has a terrible horizon for an amateur astronomer. Houses block most of the lower 30 degrees of the sky to the south and east, there’s heavy light pollution to the west now from an industrial estate, but I’ve a much better northern horizon.

For that reason I tend to favour circumpolar constellations that are accessible all year round, providing an unbroken record of observations. I’m concentrating on Cassiopeia, Cepheus, Draco, Ursa Minor and Ursa Major.

There are currently 49 variable stars on my observing list of which I have to admit only 30 get regular attention at the moment, and all of those are in the constellations mentioned above.

Making observations

I use a combination of instruments depending on the brightness of the star and the sky conditions.

I can monitor variables with magnitude brighter than 5 with my naked eye (as long as I’ve got my glasses on!). A pair of 2.1x binoculars extends this to 7, but from around there down to magnitude 9 can be handled by a 10×50 binocular on a good night, and 15×70 binoculars for the fainter end on a night of poor transparency.

These can be pushed to magnitude 10, but around that I fall back on my first telescope: a Skywatcher 130P (130mm F5) newtonian. With the right eyepieces it provides good 1 and 2 degree field of view, which is plenty of room for the variable and comparison stars near the centre.

My final limit is about magnitude 12–13 depending mostly on altitude and transparency.

A good example is the recent CTA 102 quasar which reached around magnitude 11.5 and should have been possible. But by the time I had a clear sky – bad weather – CTA 102 was low in the western sky glow and had faded to magnitude 12.7. With the Moon right on its doorstep it proved just too faint for any of my telescopes. I suspected as much, but its not every day you get the chance to see something eight billion light years away with your own eyes, so I had to have a go! I found the field stars, but no quasar. I could have filed a “fainter than” observation, but it didn’t seem worth it when I was limited to 11.4.

I try to observe these rare opportunities – the Nova V339 Delphini and SN2014J in M82 spring to mind – as they’re not often within my range of magnitudes or a part of the sky I can see.

Making regular observations of selected stars really has its benefits though, quite apart from the fun of following their progress. Practice makes perfect and with the comparison stars fresh in my mind I can manage one observation every three minutes, which is quick by my meagre standards, and maintain this rate for a couple of hours.

I just noticed on the AAVSO website that I might get another award for the first 1000 observations. I also noticed that the next milestone is 5000!

Experiences of Remote Imaging

Way back in at the beginning of 2014 I wrote about remote imaging. I know, not very analogue, but my reasoning is that using robotic telescopes wouldn’t cost me valuable observing time under clear night skies.

In this post I want to talk about how this works in practice and whether astro-imaging and astro-photography are really the same thing. I learned a bit about which one interests me the most… Continue reading Experiences of Remote Imaging

Starting to Observe Variable Stars

If you’ve read the “about me” page you’ll know that I’m a fan of variable stars. Most of my astronomy colleagues think it’s a bit weird, but I love to test the ability of my eyes to judge brightness and follow the changes in the 30 stars on my regular programme. I now use my naked eye, binoculars and a telescope to observe variables, but I didn’t start that way… Continue reading Starting to Observe Variable Stars

The Veil Nebula in a small scope

I’ve become a little obsessed with observing this particular supernova remnant. I think it’s because it can show lots of nebulous goodness under less than perfect skies and with less aperture than some: it’s a realistic target.

That said, it’s not straightforward with a light polluted sky, but mid-summer is the best time to try with Cygnus right overhead, and that’s what I do every year.

I’ll admit to being a little late with this post, but I hope you’ll bear with me since this tale was certainly an observing highlight of 2016. Just imagine that it’s August and time to start my annual Veil Nebula hunt… Continue reading The Veil Nebula in a small scope

Observing in 2016

I guess it’s obvious that I wasn’t blogging much in 2016, but I have been writing for my local astronomy society newsletter which has obviously drained my creative well… that’s my excuse anyway.

I have be observing and probably more intensively than ever. Having posted a real article I thought I’d do a round up of my rough and ready observing statistics for 2016.

If you haven’t seen 2015’s and feel you need some context then “Observing Patterns” is the place to go.

How did 2016 stack up?

I keep a diary in which I note the weather conditions at night, whether I got out there, and if not what stopped me. Summarised here is the number of observable nights – remember my loose definition – and the number I actually observed.

My observing record for 2016

Not unlike the one from 2015. I averaged about 7 observing sessions per month last year too, and took advantage of 78% of opportunities presented.

The stand out month has to be June with one single session.

In my defence, the month of June isn’t ever dark here in the UK and the weather last year was miserable. As you can see there were only 5 nights available and they weren’t very good. In fact June 2016 was by far the worst astronomy month I’ve experience to date, so I at least have decided to cut me some slack 😉

So how was the Solar?

I think this chart tells the story very nicely.

My Solar observing record for 2016

I did a lot more Solar work in 2016 than in the previous year: 2016 had 67 sessions, whilst 2015 saw only 28. I also stretched the solar season a little too.

These are both white light, which increased, and hydrogen alpha observing sessions. I’m pretty happy with my solar progress last year and hope for more of the same. It’s been great fun.

Was 2016 what I expected?

For once I think things turned out much as I’d hoped… which can’t be said for many other aspects of 2016.

I’ve completed some solar sketching of both white light and hydrogen alpha features. I plan to carry on in much the same vein this year.

I concentrated on learning my lunar geography and geology over the last year, the result of which is that I’ve spotted some regions of particular interest for close study this year.

I revitalised my variable star observing towards the end of last year as I targeted 1000 submitted observations. I’m becoming even more stellar obsessed, so much more variable and double star action to come in 2017.

I’ve advanced my deep-sky observing skills whilst furthering my binocular census of the Messier objects, starting the Herschel 400 with small scopes and getting better observations of the Veil nebula using an even smaller scope (another story).

On a sad note, I soaked up the last of the planetary goodness for a while, observing Jupiter whenever it was visible. The gas giants are sinking way too low for me for the next few years. So despite recently observing the last of the major planets to escape me – Neptune – and last year spotting Titan in the C90, planetary observing isn’t likely to feature in 2017.

And of course, I expect to remain aperture challenged 😉

An Unexpected Moon

It was the 8th January 2017. The morning had been lovely with sunshine in place of the predicted fog! It didn’t last. As the afternoon wore on the clouds gathered and by nightfall not only covered the sky but had delivered a persistent drizzle.

So I didn’t expect much when I stuck my head out of the back door at around 22:20 UT. The first thing that struck me was how warm (6°C) it felt despite being dressed in a T-shirt and lightweight fleece pullover. Then I noticed how damp it felt: our local humidity was nearing 100% it seems.

Not expecting much I looked up to the south west and I noticed something bright. The Moon was punching through the rapidly moving clouds well enough to be quite observable!

The Moon at 10.7 days into its lunation
The Moon at 10.7 days into its lunation in Virtual Moon Atlas
Continue reading An Unexpected Moon

Observing Patterns

I’m alive, well and still observing… I’m just not writing about it much.

We’re halfway through the observing season and the weather in the UK hasn’t been helpful. I’ve still managed to clock some hours under the night sky, and I’m finding it useful to keep a record.

Keeping track of observing data.

In February last year I decided to start keeping track of my observing activities and the weather that sometimes kept me from doing so. At the end of the year I added up the totals and here they are.

Chart of my astronomical observing record for 2015

I should mention that my definition of clear is pretty generous. If there’s a half hour spell between the clouds, that’s a clear night; if it’s cloudy enough to make the constellations hard to see, but the Moon is about, it’s clear.

On the other hand, there will be times when it’s been clear but I haven’t noticed it. I have to admit that I don’t constantly watch the weather outside for a chance, and I do sleep too.

So caveat aside, what does this tell me?

Firstly it tells me that I took 77% of the opportunities to observe that the weather chose to present me.

It was a good start to the year, in fact so good that it enabled me to work out that other activities enforce a practical observing limit somewhere in the mid-teens. I’ve not been too far from that at times, which I’m satisfied with, and considering my other obligations and a couple of prolonged bouts of illness it’s been a good year overall.

Summertime blues

Unfortunately, the observing cliff in the middle of the year was partially due to the aforementioned illnesses, but more particularly two issues of orbital mechanics.

The first is that it doesn’t get properly dark until nearly midnight around the summer solstice, and only stays that way for a couple of hours. It never reaches astronomical darkness at that time of year, so some objects are very tricky for the analogue observer without GoTo as signposts can be few and far between. There are many of my deep-sky friends that completely close down for the summer: kind of inverse hibernation.

That said the skies weren’t bad. I experienced some lovely transparency and managed to find the Veil and North American Nebulae for the first time with a little help from my new Astronomik UHC filter. Little did I know that I’d come to miss those skies.

And then the solar system picks on me in particular because I do almost all of my observing from home, I don’t own a car, and I don’t like driving much anyway.

Having found joy in lunar observing early last year I discovered that the Moon never strays high enough in the summer to be visible over the top of the houses from my garden. The planets are rather low in the ecliptic at the moment too, and intend to stay that way for a few years! I couldn’t see Saturn from my garden at all… which was upsetting. I wasn’t pleased, but the Universe didn’t seem to care about that much, so I’ve had to make different plans. It did reduce the options to fill observing time in those bright summer evenings though.

My ST-80 on a photo-tripod provides a grab-and-go facility, but it’s not ideal for either planetary nor lunar observing. In an attempt to remedy this problem I’ve resorted to retail therapy and bought a Celestron C90 in the hope that greater mobility will help in 2016. I like this scope already: it’s compact and as easy to mount as the ST-80.

So what did I do instead? I found that the Sun puts in more of an appearance as the Moon plays hard to get, which is shown in by the number of solar sessions below.

Chart of my solar observing sessions in 2015

These seasons pick up the slack nicely and mean I don’t have to wait for it to get dark. I intend to do more white light and hydrogen alpha observing, and sketching, in 2016. Oh, and more nebulae too. They’re addictive.

Autumn!

Don’t worry, the dark nights are on their way I thought. Frankly what constituted a clear night in autumn (fall) 2015 had to be very broadminded.

We’ve had unusually warm and wet weather from the south-west which has produced the night time temperatures of summer, which never seem to happen in summer! It’s also brought lots of cloud.

What’s worse is that the moisture in the air has made even cloudless nights appear milky: washing out most deep-sky objects and many constellations. I was pleased to see the return of the Moon this winter, since the poor transparency has frequency made it the only game in town.

On occasion the Seeing has been a compensation: there have been really good spells. This has been perfect for observing lunar and double stars with a small refractor, which I do as much as possible.

Observing in 2016

Winter has yet to arrive at the time of writing, but the next few weeks look hopeful: forecast is for it to get cold and clear. I hope they’re right.

Tracking my observing through the last year’s varying conditions has caused me to consider my choice of equipment more carefully, and perhaps more importantly, diversify my observing goals. I’ve been asking myself, what gets me out there?

It’s one of those times that I’m glad I don’t own a big scope. My small scopes, with their rapid cooling time, can be in action in a few minutes without the need for an observatory. Perfect for the conditions I’ve been experiencing. I’ve decided to stick with them, so the 10–14 inch dobsonian mounted scope is shelved for the moment, since many of my autumn sessions have been a sequence of half hours between rain showers. It’s an interesting challenge to see what you can do with limited aperture.

I expect 2016 to contain much more lunar and solar sketching, the former for the winter and the latter in the summer. Double and variable star observing remains unchanged because I love it. The biggest change is that in addition to open clusters I’ve become obsessed with planetary nebulae. They’re an interesting test of your observing skills and many are accessible to small scopes from light polluted locations.