Symbolic Forest

It’s been quiet around here lately, partly because I’ve been trying to hide from the various summer heatwaves, and partly because I’ve been beavering away at something else in the background. I’ve set up a YouTube channel, and have posted my first proper video, the start of a Lego build. It’s only small, and I’m still learning, but one thing I’ve already learned is that coming up with the idea, shooting all the footage, writing the narration, recording it, editing the whole thing together…well, it’s a lot more work than just writing a blog post.

It makes me think, actually: years and years and years ago, Radio Scotland had a documentary about blogging, and included posts from me, read by an actor. I wonder if the actor who played me found it as much effort.

Incidentally, after the previous post on the Perseids, I did go outside for a while each night last weekend, lie down on the grass, and watch for meteors. There were a few, each night, streaking across the sky; and lying on my back looking up seemed to be the best, most comfortable way to get a full view of as much of the sky as I could. The grass is much nicer for lying on, at this time of year, than it will be for the big meteor showers of winter.

Keyword noise: videos, crafting, Lego, astronomy, Perseids, meteors, meteor shower.

Just as it was this time last year, it’s Astronomy News time because we’re coming into the season of the best and biggest meteor shower of the year, the Perseids, which reach their peak next weekend. This year the peak coincides roughly with the full moon, which is in the early hours of Friday morning, but hopefully the brightest meteors will still stand out—or you can always wait a few days into the following week, because the like most meteor showers you can still see plenty of meteors in the few days either side of the Perseids’ peak. Get a chair you can lean back in, sit outside on a clear night, and watch the sky until you see them flash across it.

Incidentally, Saturn is also the largest it gets in the sky at the moment, as we’re the closest that we will be to it this year. I might be tempted, if there’s a clear sky, to get the telescope out and have a look, to see how well I can spot its rings. Of course, annoyingly, it will also be close in the sky to the full moon next weekend just because that’s how the geometry of the solar system works. The moon is full when it’s directly opposite the sun from us. The outer planets are closest to us when we’re directly between them and the sun—which is the same thing. At least the moon moves relatively quickly in the sky, day to day, so even one day after the full moon it should be far enough away from Saturn to not be too much of a problem. I’ll just have to hope the skies are clear.

Keyword noise: astronomy, meteors, meteor shower, Perseids.

Time for me to point out another of those regular events on the astronomical calendar. We’re just coming into the season of the Lyrids meteor shower, which should peak a week on Sunday in the early hours of the morning. So, if you fancy going meteor-spotting, next weekend is your best chance to do it until August. The phase of the moon makes it not too promising this year, but meteor-spotting is one of the easiest and simplest forms of astronomy there is, so if you fancy it and don’t mind being up in the middle of the night, go out and give it a try. The Royal Observatory Greenwich has some advice, but essentially, all you need to do it sit in a dark spot outside, look up at the sky, and relax.

Keyword noise: astronomy, meteor shower, meteors, Lyrids.

If you’re into astronomy—or if you were reading this blog this time last year—you might remember that the first week in January is home to one of the big annual meteor showers, the Quadrantids. I still keep meaning to write a blog post about Quadrans Muralis and other forgotten constellations, and I’m sure I will do at some point. Anyway, as I was saying, last night was the Quadrantids’ peak night.

I went outside at 7 or so for an evening walk, and the sky was beautifully clear, with what felt like it would be excellent seeing. Unfortunately, it was also bloody freezing, with a strong wind blowing, and I was exhausted from my first day back at my desk after the long Christmas break. So, an early night, and no Quadrantids for me.

About half two I woke from bad dreams, and considered getting dressed, dragging a garden chair out and going outside. I could hear the wind blowing gustily, though, and howling around the gutters. Moreover, I’d already worked out that the radiant, here, would be in the direction of the worst street-lights in any case. “Maybe not tonight,” I thought, and turned over and tried to get back to sleep.

There will still potentially be meteors to see tonight, of course, and if the seeing is good again I’ll at least consider taking myself outside. I might have to dig out my warmest clothes and put them to one side first, though.

Keyword noise: astronomy, meteors, meteor shower, Quadrantids.

Back in August I talked about how Jupiter and Saturn were nicely visible in the sky, but not until well after The Children were in bed. Last night, though, we had a rare family conjunction of myself and The Children being in the same place, on a night when it was dark well before their bedtime, with a largely clear sky. So, the telescope came out.

This was the first time The Children had been able to use the telescope this autumn, the first time since a few abortive attempts just after moving house in February. I was impressed, to be honest, how over nine months they have grown that bit more mature to be able to use the telescope a bit better. Last winter, it was difficult to get them to stand still long enough to look through a telescope properly, difficult to get them to look through the eyepiece without grabbing onto it and swinging it out of position, and difficult to get them to wait patiently whilst I aimed and focused it. Now, though, they managed to do that with a few different things. FIrst we looked at Saturn, its rings angled and nicely visible; then at Jupiter and the four Galilean Moons. I couldn’t really see any cloud bands on Jupiter this time, unlike in August, but nevertheless the children were pretty excited.

There was a fair amount of patchy cloud; some constellations were visible but nothing exciting enough to hold The Children’s interest. In any case, it was almost bedtime. I left the telescope set up, though, and after a few hours the clouds had largely cleared and we went outside again. Orion was just rising; we looked at the nebula, and at Betelguese, and the Pleiades. The night sky, still just as it was last winter.

Keyword noise: astronomy, planets, Jupiter, Saturn, Orion, Orion Nebula, Betelguese, Pleiades, The Children.

An upcoming astronomy event: in a couple of weeks time, on October 16^th, it’s International Observe The Moon Night. The idea being, everyone gets together around the world and, well, looks at the moon.

You might expect an event like this to happen on the full moon. It’s not, however: the moon will be waxing gibbous, a couple of days after passing First Quarter. In many ways this makes it a more interesting sight, as there will be a day/night terminator visible. That is: the line between the bright sunlit part and the dark night-time part. If you get a telescope or binoculars and look at the terminator, you can see the low-angled sunlight picking up ridges and hills, and casting deep shadows into the craters. Because the moon has essentially no atmosphere, the picture you see will be wonderfully crisp and sharp, the ridge of every crater picked out perfectly.

The Moon might be the nearest heavenly body, most of the time, but there’s still an awful lot we don’t know about it. Moreover, it’s fascinating just to go outside and look at. On International Observe The Moon Night you can go and join an established event, or you can put your hand up to host one yourself. Or, if you don’t like either of those options, just go outside and look at it yourself. It will—clouds permitting—be beautiful.

Keyword noise: astronomy, moon, The Moon.

We’re getting to the time of year now when it’s properly dark before a reasonable bedtime; as opposed to a couple of months ago, when it is still twilight in the deepest part of the night, which around here happens at about quarter past one in summer. August, by comparison, is the time of year when I can go outside at 10pm and see if the sky is clear enough to do a small bit of stargazing before bed. It’s too late to wake up The Child Who Likes Space, who nominally owns the telescope, but nevertheless, I rationalise, I can always tell him about it in the morning.

A while ago, I noticed that according to timeanddate.com’s planet apparent size calculator, Jupiter would have a relatively large disc right now. Right now, in fact, it’s receding from us, but it’s still a relatively chunky 49 arcseconds wide. Still a dot to the naked eye—the Moon is about 36 times bigger in apparent diameter if my rough mental calculations are correct—but big for a sky object, and with the best chance we would have of seeing features on it. Over the past few weeks I’ve noticed that Jupiter and Saturn together, although relatively low in the sky, are very definitely the brightest things in the south-eastern sky when I go to bed. So last night, as the sky was almost clear, I decided to get the telescope out.

Last spring I found it rather hard to get the telescope set up in the new garden, due to the street light that shines directly into it over the garden wall. Back then, though, the garden was a rocky, rubble-strewn wasteland, which didn’t help. Now it’s grassed, and at the moment I can tuck the camping table and the telescope into a relatively shady distant corner; from which both planets were shining bright in the sky. It was as easy as any astronomy I could think of: set up the telescope, point the finder on Jupiter, and as soon as I had focused, I had the planet and the four Galilean moons right in the centre of the eyepiece. All four of the moons were on the same side of the planet last night, Io just visible almost touching the planetary disc, the other three clear and sharp and separate spread out to the east of the planet. Jupiter itself was a fairly uniform cream colour, with a thin, darker, more reddish band visible near its equator. It seemed so sharp and clear, much more clear and bright than a photograph.

After Jupiter, I trained the spotter on Saturn, much smaller in the sky. At first it just seemed to be an oval blob, but I’d knocked the focus off slightly. Tweaking it showed the planet, orange in colour, and its rings. We don’t have anywhere near enough magnification to show the ring divisions, and the rings and the planet seemed to have a fully uniform colour. It’s strange to think that when Stegosaurs were alive and tramping the planet, Saturn probably didn’t have any rings at all. I couldn’t make out any of the planet’s moons, but I know they are much fainter than those of Jupiter, my eyes probably hadn’t had time to fully adapt to the dark, and I didn’t know where to be looking in any case. I wonder how different the history of science would have been, if Jupiter didn’t have four clear bright moons for Galileo to spot easily with his early telescopes.

Incidentally, due to geometry, it’s impossible for the planets orbiting outside Earth to have phases like the Moon does: their discs will always appear from our standpoint to be fully illuminated. This coming winter Venus will be the largest planet in the sky—it peaks at just under 63 arcseconds on January 8^th—and it will be interesting to see if around then more than a thin crescent is visible. Assuming the skies are clear, of course.

Keyword noise: astronomy, planets, Jupiter, Saturn, moons, Galilean Moons, Io, Venus.

You might remember, if you’ve read back as far as last March or April, that I’d been trying some astrophotography but hadn’t got very far. I still haven’t got very far, largely because it’s summer, and we are only just out of the part of the year where it never gets properly dark at all here.

The other day, though, regular reader MdeC was grumbling on their social media that their attempt to take a gorgeous photo of the Milky Way—far better than anything I’ve produced—had been ruined by a meteor. And it reminded me: we’re just coming into one of the key meteor-spotting seasons of the year. August is the month of the Perseid meteor shower, one of the busiest and brightest showers in the calendar. The fact there are lots of meteors in the sky in August has been known since ancient times; in the 19th century the astronomer Schiaparelli calculated they were created by the trail of dust left behind by Comet Swift-Tuttle in its orbit. Their peak will be next week, on Thursday night and Friday morning, but they are spread quite broadly, and any clear night over the next couple of weeks gives you a good chance of seeing some.

So, if there’s a clear night, I’ll be taking a deckchair outside, lying back and looking up at the sky. There’s no point really setting up the telescope or getting binoculars out: they move too fast and can be anywhere in the sky. Just relax, find a dark place if you can, let your eyes adapt, and watch them flash across the sky.

Keyword noise: astronomy, meteors, meteor shower, Perseids.

A couple of weeks ago now, I mentioned that I’d been outside and pointed the camera up at the sky to see what happened. It’s about time, I thought yesterday, that I tried to actually see if I could make the photos that resulted useful in some way.

This is all down to a friend of mine, Anonymous Astrophotographer, who I won’t embarrass by naming, but who manages to go out regularly with a camera and a tripod and even without a telescope produce beautiful pictures of the Milky Way and various other astronomical phenomena. I asked them what their secret was. “Nothing really,” they claimed, but gave me a bit of advice on what sort of software to try a bit of image-stacking and so on.

I thought, you see, that given that The Child Who Likes Animals Space’s telescope doesn’t have an equatorial mount, it would be pointless to try to attach a camera to it. You can, after all, visibly see everything moving if you use the highest-magnification eyepiece we’ve got at present. Equally, surely it would be pointless just to point my SLR up into the sky? Apparently, not, Astrophotographer said. The trick is to take lots of shots with relatively short exposure and stack those together in software. The exposure should be short enough that things don’t get smeared out across the sky as the Earth spins—anything over 20 seconds is probably too long there—and the number of shots should in theory even out random noise in the sensor, stray birds, and so on.

As a first attempt, I thought, there’s no point trying to get sight of anything particularly special or impressive, so I pointed the camera to a random fairly dull patch of sky and see what happened. You can click to see a larger version.

This is an arbitrary area in the constellation of Draco. In the middle you have Aldhibah, or ζ Draconis, with Athebyne (η Draconis) over on the right and the triangle of Alakahan, Aldhiba and Dziban over on the left. The faintest stars you can see in this image are about mag. 7.5, maybe a little fainter, which is a bit fainter than you could see with the naked eye even in perfect conditions. This image has been adjusted slightly to lower the noise; in the original you could just about persuade yourself you could see mag. 8 objects, but they were barely distinguishable from noise. The Cat’s Eye Nebula (NGC 6543) and the Lost In Space Galaxy (NGC 6503) are both theoretically in the picture, in the lower left, but they’re not visible; the former can just about be spotted as a faint pale patch very different in shade to the noise around it on the original images, if you know exactly where to look.

Here’s the handle of The Plough, with the stars Mizar and Alcor together in the middle. This one really doesn’t look much at a small size, but if you click through you can see how well the camera captured the different colours and different shades of starlight. Again, the darkest things visible here are about mag. 7.5. The Pinwheel Galaxy is right in the middle of the lower centre, but at mag. 8 or so doesn’t come out of the noise at all.

What do I need to do to make things better? Well, for one thing, the seeing wasn’t actually very good on the night I tried this. As I said in the previous post I had to give up fairly quickly due to cloud. What I hadn’t realised, until I saw the photos, was that faint clouds, lit up by moonlight, were already rolling in well before it became obvious to the naked eye. Trying some photography again on a clearer night would definitely be a start. Secondly, my SLR is pretty old now, dating to the early 2000s. The sensor is, compared to a more modern one, fairly noisy at low light levels. I’m not going to rush out and buy a new camera tomorrow, but I do suspect that if I did, the attempts above would get quite a bit better.

Keyword noise: astronomy, photography, astrophotography, Draco, Ursa Major, Aldhibah, Athebyne, Mizar, Alcor.

Those of you who read yesterday’s post about the Lyrid meteor shower may well be waiting on the edges of your seats for further information as to how the night went.

The short version is that I don’t think I saw any meteors. I went out after it was dark, sat in a chair, relaxed, and watched the sky. The sky was nice and clear; initially, at least. The Moon was rather bright, though, and before long high clouds started to roll in from the north-east. The moon lit the clouds up beautifully, but for anything else it was hopeless. I went in after half an hour, without a single meteor being spotted.

Still, I had also taken my camera out with me, as a bit of an experiment. I set it up on the tripod, plugged in the remote release, chose what seemed to be a good exposure and sat there clicking away. I don’t expect the results will be outstanding, not for a first quick attempt, but we’ll see what comes out of it. It might take a bit of experimentation in post-processing; I’ll keep you updated.

Keyword noise: astronomy, meteors, meteor shower, Lyrids.