Minimal Astronomy

When we imagine early astronomy from ancient times to the medieval we assume that lacking optical devices they would see only pinpoints of light fixed in their place all eternity. Sure they would have noticed that the Sun and Moon moved across that backdrop, and these stars would make interesting patterns, but that’s about all the naked eye could show you, after all we wouldn’t see much more today.

Then I realised that until relatively recently the skies were really dark. Consequently the night sky would have been far more dramatic and dynamic to the ancient eye than it is to our own. Modern skies are so bright that it’s easy to fail to notice there’s anything up there at all, and most don’t even bother to look.

The Sun and Moon are bright enough to be seen in the most light polluted sky, but the planets all the way out to Saturn are bright enough to be easily visible to your eyes, and although their true nature might not have been known they were named and their strange paths commented upon: these were not normal stars!

The rugged bright band of the Milky Way moves across the sky with the seasons being right overhead in the late summer and autumn at mid-northern latitudes. In the dark it casts a shadow so I’m told and is a mosaic of dense starlight and dark dust clouds.

They certainly noticed that the patterns of stars that give rise to the constellations also move throughout the year and gave many of them names. The fact they managed to pick these stars out of the dazzling background shows that they were really observing. Several stars were singled out as having special significance in connection with seasons.

To cap it all some of the “unchanging stars” were seen to vary in brightness, such as Algol (beta Persei), and new stars would very occasionally appear in a dazzling flash that would become known as Novae or Supernovae, such as that which created the Crab Nebula.

Comets would have been more noticeable and invested with the power of victory or doom. I can only imagine how spectacular the regular meteor showers would have appeared.

I would love to experience those skies, but I really don’t like to travel and few places in the World remain where you can see what the ancients might have. All the same much of what I’ve mentioned is available in a diluted version to modern unaided eyes (well perhaps with glasses).

I’d urge you to try really observing the Moon and see what you notice; have a go at making brightness estimates for variable stars like Algol; try splitting some wide double stars and see what’s the closest you can manage; and examine the large scale structure of the Milky Way. You don’t need any equipment to be an amateur astronomer.

Observing in 2017

I think it’s fair to say that I was more active on the blogging front in 2017. Unfortunately I appear to have fallen off the wagon again, so I’ll try to get things rolling with my traditional summary of the last year. I’ve a few more ideas after that so who knows?

The results for 2017

Going back over the diary for 2017 shows about a third of the nights to be observable based on my loose definition.

My Observing Record for 2017
Chart of the monthly figures for the nights I decided were suitable for observing and those I actually went out there.

I feel that the duration of those “clear” skies opportunities have declined, especially in the autumn, a point born out by notes in the diary. There’s no doubt that the quality of my home skies have been in decline for some time due to atmospheric moisture and the rising light pollution from the nearby industrial estates.

Many of those months make great use of the fact that the Moon is quite observable in even relatively cloudy conditions, and the light pollution doesn’t matter one bit. In fact I normally observe the Moon with a bright white light to illuminate my atlas and journal.

I have indeed started lunar sketching in the last year… but not well enough to share yet. At the close of the year I’m down to the final ten sights in the Lunar 100, and some of those will need just the right libration.

The Herschel 400 (H400) list is actually the Herschel 281 for me since I’m limited to objects above the celestial equator. It’s gone reasonably well since I started it last year with 92 objects observed despite the poor deep-sky conditions.

I have pretty much run out of Binocular Messiers to observe from my garden and started on the low altitude Summer Messiers. I’m about a third of the way through this project and progress has been very slow.

Variable star observations topped 1300 at the end of the year and I did receive my certificate from the AAVSO for my first 1000. I was aiming for 1500 in 2018, but that’s going to have to be revised… I hope.

What about Solar?

I’ve been just as active as in 2016 but with a lot more sketching in both Hα and white light using the Herschel wedge… and cheap binoviewers which are excellent for white light in my Starwave achromat.

Solar Observing Record 2017
Chart of my solar observing activity in 2017.

OK, not quite as many sessions as a packed 2016, but I felt that the quality of the work I was doing was much higher. Most sessions had a sketch and detailed notes.

My plans for 2018

To be frank it’s not started well. Lots of poor weather and a prolonged illness have made it impossible for me to get any scope time for the last month.

Unfortunately I’ve now observed many of the fun objects in the H400 and there are a lot of galaxies remaining. I’ll admit that I’m not a big fan of galaxies. This is partly being limited to 150mm of aperture, which I may able to do something about, but also the poor quality of my sky: any haze and glare makes galaxies invisible.

I’ve kicked off a couple of new programmes focused on objects visible from my home site to make up for a galaxy infested H400.

  • The resurrected and revised version of the Astronomical League basic open clusters programme containing 88 clusters.
  • A programme to observe 56 bright planetary nebulae.

I have another that may prove to be insane from my garden: 34 objects from the Sharpless HII Regions catalogue. They’re the ones that Stewart Sharpless gave a ‘3’ for Bright, though I suspect that to be a relative term. We’ll see how that goes, I may have for travel far afield to complete it, or leave the Country.

I want to finish off the Binocular Messiers but I need to find a better horizon. I have a few ideas that are considerably more local than those for the Sharpless project and at least binoculars are nothing if not portable. The majority of the outstanding Messiers are spring and summer objects, so I’ll need to get started soon.

Lunar observing is guaranteed to continue. The final few Lunar 100 sights may be a question of waiting for the right opportunity, but I’ve identified a few features of special interest to pursue, research and perhaps even sketch well in the process.

I’d like to try and observe Venus a again this year, but the apparition isn’t very favourable, just better than for all the others. I caught a brief glimpse in binoculars last night at only 5º above the horizon: no chance of getting a scope on it. The planets are mostly hopeless this year I’m afraid.

We march towards solar minimum in the next couple of years, and despite some fireworks last year the beginning of this one hasn’t been promising. The Sun is very quiet. Is this the right time to start learning how to do sun spot counts? I hope for better by the summer.

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.

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.

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 😉

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.