It was 98 years ago today...

Happy Tunguska event day.

File Under: Tunguska.

And then there were three...

It seems that accidental observations of Jovian events is something I'm prone to at the moment. Just a couple of weeks ago I "accidentally" observed a shadow transit and then, last night, I managed to "accidentally" observe the start of a transit by Europa.

Makes me wonder what I could get done if I was organised and prepared... ;-)

File Under: Jupiter, Transit, Europa.

Solar Checking

A couple of days back I got round to acting on my search for data that can be used to see how well I'm doing with my sunspot counts.

The Solar Influences Data Analysis Center (part of the Royal Observatory of Belgium) have a sunspot data download page with all sorts of handy things available. I've now set up a system that lets me grab daily sunspot data for any given month, as it becomes available. I've also modified the code that displays my counts on my site so that the SIDC data is displayed side-by-side with my counts so I can compare the numbers.

You can see an example of this in the figures for May. There are differences, in some cases rather large differences (I expected this), but I was also heartened to see that the general trend in my counts seems to follow the "official" numbers.

File Under: Sun, Sunspots, Solar Observing, Solar Influences Data Analysis Center, Royal Observatory of Belgium.

Solar Weather Browser

Despite working with rather lowly equipment I've found myself getting more and more fascinated with solar observing — just the simple act of doing a sunspot count as often as I can has me rather enthralled.

This evening I was looking around the net for a source of sunspot numbers held in a sensible format¹ with a view to writing a small tool that would auto-compare my counts with the "official" ones to see how well I was doing. During that search I stumbled on The Solar Weather Browser.

SWB is available for Windows, MacOS and various types of Unix (including GNU/Linux, of course) and it seems to be an amazing bit of software. Think of it as the solar equivalent of the Virtual Moon Atlas.

If anyone out there is interested in following what's going on on the Sun and they want a tool that lets them view it in all sorts of ways (with the ability to travel back in time too) then they they should give SWB a serious look.

File Under: Sun, Sunspots, Solar Observing, Astronomy Software, Solar Weather Browser.

---

¹ I'm still looking. I've got one or two candidates but a source that publishes an RSS feed or some other form in XML would be really handy.

Luna goes LPOD

Luna, the magazine of the Lunar Section of the Society for Popular Astronomy is today's entry over on LPOD.

File Under: Luna, Moon, Society for Popular Astronomy.

Solar graphs

I've just uploaded a new addition to my astronomy site: a page of solar graphs. The graphs are updated each time I record a new solar count.

At the moment I'm not really sure that they're that useful or have a sensible purpose. I guess, if nothing else, over a long period of time, I'll be able to see for myself how solar minimum turns into solar maximum.

File Under: Sun, Solar Observing, Sunspots, Graphs.

A first and a century

I finally had my 100^th observing session last night, and it was quite a treat too.

Early in the evening the skies were looking pretty clear (just some thin cloud and haze around, the Moon had a bit of a halo) but still very bright. However, I noticed that Jupiter was placed such that I'd be able to see it from my back garden (it's mostly been out of view for me this apparition because it never rises about my house and it's very difficult to observe from the front of the house). Given that not a lot else was going to be visible at a reasonable hour I decided to get the 905 out and have a look at Jupiter.

At first the image was pretty awful but, as the 'scope cooled, things improved. I could see three Jovian moons, two some distance either side of the planet and one quite close. As I watched and waited for steadier moments I kept noticing a very clear, dark and well defined spot near the north pole of the planet. Given that I was unsure if I was seeing things I swapped eyes, rotated the eyepiece, shifted the 'scope around a bit — anything to eliminate some artifact from something. The image of a dark spot persisted.

I then came into the office and fired up Starry Night Enthusiast 4.5 and zoomed in on Jupiter and, sure enough, there it was: the dark spot I was seeing was the shadow of Ganymede! Not just my first ever sight of a shadow transit but a totally accidental find too.

I first noted it in my log at 21:58UT (I estimate it was just over ½ way through the transit — I've not checked the times anywhere yet) and last caught sight of it at around 22:15 (when I finished making a rough sketch of what I was seeing so I could check things later on). After that some cloud got in the way and by the time it had cleared (around 22:50UT) I couldn't make the shadow out any more.

It was a really enjoyable experience. Not only had I seen a transit, I'd "discovered" it by accident — that sort of made it all the more special.

Edit: I've now published the observing session notes.

File Under: Jupiter, Shadow Transit, Ganymede.

Turning 100

Last Friday evening I had a bit of a fiddle with the code behind my online log system and ended up adding a facility that generates some simple statistics about the logs.

As of today's solar observing session I've had 99 observing sessions. One more to go and I'll have made it to 100 sessions. Just like when I filled by first log book, I know that it's somewhat arbitrary as a measure of progress, but it still feels like some sort of milestone. It's also interesting to note that over ½ of those sessions have involved the Solarscope — that confirms that I've made more solar observing sessions than anything else. That's not really surprising given that it's much easier to find a clear moment during the day than it is during the night.

File Under: Astronomy, Observing Logs, Milestones.

Grumpy old man

I seem to be having another one of those annoying times in regard to astronomy. The weather has been pretty awful for the last few weeks (during the night anyway) but the last two nights have been nice and clear. The only problem with this is that I'm just starting to throw off some sort of illness (one of those nondescript "bug" things that come around from time to time) and I've also got a stinking cold that developed towards the end of the first illness.

Also, to top it off, the swollen eyelid I developed back in March came back in the last few days. I went to see the doctor today and it seems like it's a Cyst on my eyelid (although nowhere near as bad as the one illustrating that article) and that it'll probably be a permanent thing. It seems the options are that I just put up with it swelling up from time to time (and treat it with a hot compress in the hope that it might make it go away) or I have some minor surgery to remove it. To just make it more fun it's in my main observing eye.

Okay, that's all the really Grumpy Old Man stuff out of the way. I feel much better for that. ;)

On a more positive note last month was my best month so far for solar observing (spotting breaks in the cloud during the day is so much easier isn't it?) and I've been really enjoying it. At some point I think I'll need to get into it a bit more, improve my methods of counting and cataloguing active areas and spots and try and write more descriptive reports.

I'm also quite taken by the idea of this solar observing binocular that Scopes'n'Skies have added to their site. On the surface they seem quite good for the price.

File Under: Moaning, Grumpy, Solar Observing.