The Scruffy Astronomer

I've shown astroterrestrial photos before, photos with a subject on the ground with a night sky background. Here's a stunning example. It's Uluru (obviously) from the viewing area with the South Eastern sky behind it. The photo was taken by Prasun Agrawal a little while back, and I was knocked out by its quality. I love the hook shape of the Rho Ophiuchi cloud complex near Antares. But there's more to the image than than this. You can easily see details in the rock, such as Kantju Gorge on the mid-left, that interesting line of circular features in the centre of the rock, and bushes in the foreground. It's an unusually high level of quality. How did Prasun do it? It's a composite: a common way of producing this type of image. Single images are more challenging as you need to focus separately on foreground and background. With a composite, you take a single foreground image and combine this with a "stacked" image of the sky. The stac...

Just take a look at this photo of M16 - the Eagle nebula. The Pillars of Creation are right in the centre of the image, and to the left there's the Stellar Spire. Note the horseshoe shaped structure at the top of the nebula - I'll get back to that. John uses a saxon 127mm FCD100 triplet refractor. This is one of the big ones. For an imaging array, John uses the popular ZWO ASI1600MM-Pro monochrome camera and shoots through narrowband filters. All his exposures are four minutes long. John has presented his image in the so-called "Hubble Palette", where images taken though the Sulphur filter are shown as red, those taken though the Hydrogen alpha filter are shown as green and those taken through the Oxygen filter are shows as blue. As a contrast, here's one of my own photos of M16. It's taken with similar equipment, an ASI1600MM-Pro, a slightly smaller 107mm triplet refractor and narrowband filters, which are presented using the Hu...

The Tianhe-1 is the first part of the new Chinese space station. If you like, it's an orbiting foundation, but more accurately, it's called a "core module". At 16.6 metres in length and 22.6 tonnes, it's big already, but it'll grow as the Chinese Space Agency adds modules. It's got several docking ports to allow expansion as well as providing parking space for service vehicles. It was launched on 29 April on top of a Long March 5B heavy-lift rocket. The launch went well and the upper stage of the Long March rocket reached the planned orbit. After dropping the payload, it was probably meant to restart and slow down. This way it would fall back to Earth not far from the launch point. This didn't happen, and the 21 tonne rocket remained in orbit, rising to over 240km, and then dipping to about 150km every 90 minutes. The rocket was also tumbling, indicating it wasn't under control. With each dip in altitude, the rocket brushed the upper atmosp...

Peter Kinchington sent me this dramatic image of the Carina Nebula in narrowband a while back. He took it using an ED80 refractor from his place in Mooroolbark (not far from the shop). For those of you who are used to seeing Carina as pink, this is a false colour image, using the "Hubble Palette". Peter has used a monochrome camera (in this case, a QHY163M) which captures the light produced by ionised Hydrogen, Oxygen and Sulphur in the nebula. Visible light is made up of a whole spectrum of wavelengths from different sources. A good number of these sources are ones we don't want. For example, normal DSLR photos pick up extraneous light from terrestrial light pollution from street lights and your own house. It'd be nice to be able to get rid of this light. On the other hand, you really do want the light from (say) ionised Hydrogen, because this makes up the bulk of gas in most nebulas. Using the correct filter, you can. Ionised Hydrogen shines in a highly-specif...

This mind-bending image was taken by @Vincent TC (https://www.facebook.com/VincentTC1971) in the Netherlands a couple of weeks back. I was in two minds about how to present the photo - it was tempting to put it upside down! (Look at the bottom,,,) Vincent was out birding with his camera in bad weather (actually, because of the bad weather!). He got some shots of a Sea-Eagle and a Spoonbill (both different to the species we get here in Australia, of course), but this goose (I think it's a Greylag) landing in very strong wind caused a bit of a stir on Facebook. Consider the following. A bird is flying and suddenly decides to land, effectively dropping vertically to the ground. This might be due to very strong wind, or if there are raptors (or shooters) around. The bird can’t simply dive to the ground, as this would mean it would gain a large amount of speed. Pulling out of a dive like this before hitting the ground would place huge strain on the bird’s wings. The bi...

Bolides, or fireballs, are brightly burning meteors that have entered the Earth's atmosphere. Most small meteors burn up inside the atmosphere, and occasionally they bounce off the upper atmosphere before moving away from the Earth again. These provide spectacular but harmless light shows. Sometimes, however, they cause havoc on the ground. The Chelyabinsk Event in February 2013 was an explosion caused by a meteor about 20m across entering the atmosphere. The explosion released about the same energy as the Hiroshima bomb. Damage was widespread, and several fragments were recovered. Recovered fragments of meteorites are of significant interest to scientists, of course. But how do you find them? The International Meteor Organisation records meteors and bolides reported by citizen scientists. These include visual records, mostly from all-sky cameras, and the occasional sound recording. Scientists can use these to estimate the meteor's trajectory when it entere...

I came across this photo a week or two back on the ASV's astrophotography Facebook page. Sam (the photographer) had posted it because of the nice placement of the meteor, and was very modest about the rest of the shot. I was less focused on the meteor and more on the rest. After all, it's the South Celestial Pole, which isn't really photographed much. Why is it that the polar area isn't commonly photographed? To be honest, I'm really not sure, but two reasons come to mind. First, lots of people think it's a bit of a dead zone. And they've got a bit of a point. You can see straight away that the big area between The Emu (that's the Milky Way through the Cross and Carina) and the two Magellanic Clouds is pretty empty. The second reason is a bit technical. "Plate solvers", those clever computer programs that read stars and compare them to a database to determine where the telescope is pointing, have a bit more trouble in the polar area. T...

I was talking about wide-field images with a customer last year. Mal showed me a photo he'd taken while back "up north". He'd used a now-elderly Canon M3 mirrorless with a Samyang 2.8mm fisheye. Mal told me that when he took this photo, he was in an area so dark that he hadn't noticed he was underneath a powerline until he previewed the photos on the back of the camera. You can see the lines go through the Small Magellanic Cloud. We both agreed that we enjoyed working in the dark. The bluish colour on the horizon is a car on a main road. That power pole provides a subject for the centre foreground. Without it, these photos get boring - just fields of stars. The shot was less than 30 seconds at f/2.8. He'd set the ISO very high. The camera has a clever noise reduction system, which takes three "light frames" and one "dark". Noise measured in the dark frame is subtracted from the lights, which are then stacked, further reducing ...

I was chatting to someone a few days ago, and the subject of old photos came up. I have very few: this one is from the late 1970s. At school, we had a 4" Unitron refractor on an equatorial mount. We could take photos of the Moon, but deep sky objects were beyond us. Apart from the cost, taking single, long exposures was supremely difficult. The longer the exposure, of course, the better the photo, but how do you keep the telescope on the target? To guide the telescope, a second scope was mounted on the main scope. This one had more magnification, and an eyepiece with a crosshair. The operator would peer through the eyepiece for the entire time, staring unblinking at a star. The operator would compensate for drift with the mount's slow-motion controls, but these were the only movements they could risk. If the operator lost the guide star, the photo would be ruined. Because of the long exposures, a wasted photo would cost of a lot of time. It was a terrible j...

Fake video! Actually, not. But it was remarkable enough for some people to think it was a fake. We've featured one of Kelvin Hennessy's remarkable photos before . One of his favourite themes is an oversized moonrise with a terrestrial subject (often the Byron Bay Lighthouse) in the foreground. I think my personal favourite is the lighthouse with the Andromeda Galaxy rising behind. To achieve this effect, he gets a lot of distance between himself and the foreground. Because the foreground subject is very small and the whole shot is magnified by the telescope, the background Moon appears very large. In October, Kelvin made a new video, and published it on a couple of social media platforms. I've attached a few frames here, but the full video is well worth a watch. The reaction to the video was probably not what Kelvin was expecting, with accusations that it had been faked. One commenter said that the background Moon and foreground (lighthouse...

It's planet season! Jupiter is blazing away in the evening, pretty much unmissable high in the East just after dinner, and Saturn isn't far behind it. If you're up much later you'll see Mars approaching opposition. I had a good look the other night using a saxon 909AZ3 and Mars is about the same apparent size as Saturn without its rings. My mate Paul just got this shot of Neptune, which is difficult, but a beautiful blue. There are plenty of bright clusters like 47 Tuc, and dimmer objects like the Helix Nebula. or the Sculptor Galaxy. Far into the North, the Ring Nebula will challenge you. Here’s the  list of springtime objects. It spans 12 to 20 hours in RA, and is biased to the southern objects. Because we're locked down in Melbourne, it won't be easy for you to see the dimmer objects. The list is ordered by the time targets pass the meridian – that is, their highest point of the night. The Omega Nebula is past the zenith before 7pm, so go for that one first. ...

This is what you can do with a small star tracking device. Steve from Tassie recently got himself a Sky-Watcher Star Adventurer, which is like a small equatorial mount designed to carry a camera and normal lens. Steve used his Lumix G9, a micro four-thirds camera with a 200mm f/2.8 lens. This gave him the equivalent of 400mm focal length for a full frame. Using ISO 1250, he took 12 30 second exposures, which he stacked using Affinity. Final touches he did in Apple photos. As to the photo, it’s one of my favourite areas in the sky, the end of the Rho Ophiuchi dust trail. There’s so much there. Just for fun, I've put an annotated version of the photo at the bottom. The bright yellow star is Antares, the eye of the Scorpion. Above and to the left is the globular cluster M4, but between them is the smaller cluster NGC 6144. Continuing anti-clockwise, Alniyat is next, and then the smaller star HIP 80079 to the left of the shot. Below this is (for me, at least) the star of the show, Rho ...

We're getting towards the best time for viewing planets. Jupiter and Saturn are both above that critical 30° angle for good viewing before midnight. Pretty soon they'll be high in the sky at an hour that will have you asleep soon after midnight. And later in the year they'll be joined by Mars. Opposition - the point when the Earth and Mars are closest, and the planet is highest at midnight - is in late October. People are beginning to take great photos already, and you don't need hugely expensive equipment to do it. It's fantastic what you come across when you subscribe to different Facebook groups. I was browsing through one of my favourites the other day, "Budget Astrophotography", when I found these.   Adam lives in Tucson, Arizona, and took these using a manual 8" Dobsonian scope, and an iPhone 6 clamped to a 9mm eyepiece using a Celestron NeXYZ phone adapter. Each one is a single exposure - there's no stacking. I contacted Adam to find how...

People often ask me why the magnification on terrestrial telescopes is lower than on astronomical telescopes. It's because the atmosphere does horrible things to light rays. Have you ever tried looking at something on the ground with a high-magnification telescope, especially on a warm afternoon in summer? You're unlikely to see much at all. Here's a photograph of an aeroplane taking off. It was taken by my mate Paul, and I've shown some of his images before. Notice the trees in the background under the wing on the right? They're pretty clear. However, the trees that should be visible to the left through the jet engine exhaust are very blurred. Air isn't a smooth, consistent medium. It has warm and cold pockets, which act as lenses and distort light passing through. These move around chaotically, and the effect is what we call heat haze. When you magnify the image it becomes quite obvious, with the image moving about. The more magnification, the more obvious it ...

What's this mess? I took this disaster of a photo while looking (in vain) for a passing asteroid. A few days ago, it was a clear night in Melbourne. I took the opportunity to go out into the back yard and do some photography - as you do. What I was after was the Statue of Liberty nebula. ( I eventually posted it alongside a more concrete Statue of Liberty .) However, I'd heard about a close pass of an asteroid that was coming up, and thought I might be able to get a photo. The asteroid's name was (52768) 1998 OR2. Clearly a family name. From what I can gather, it's an egg shape, roughly 2km by 5km. That's big, and if it collided with the Earth it'd cause a heap of problems, but it wasn't coming closer than 16 times the distance of the Moon. It's also not a giant: the Chicxulub asteroid was up to 80km across. But it's large enough to be spotted with an 8-inch telescope. Mine is only a little more than half that, but I thought I'd have a stab in th...

My mate Mal has always been a photographer, right from when I met him at primary school in 1974. This wasn't taken then, though, I think it would have been about 1978, and I think he was mucking around with some high-contrast film. I might look casual, but I must have been teetering on a ladder! The dome is my secondary school's observatory (yes, I went to Scotch College, don't judge me). I was in the Astronomy club from the very first year I was there.  I spent so much time in the observatory with a handful of mates - several of which I'm still friends with. It was, I guess, a bit of an escape from the harsh environment that was secondary school in the 1970s. We had observation nights every term or so, and the scope in the dome was a 4" Unitron on a clockwork driven equatorial mount. We also had a 6" Newtonian reflector on an equatorial mount which was itself on a mobile pier, as well as a Brass Monster - a refractor on a wooden tripod. I was never a huge fan...

Here's a photo from a friend, Pete, who lives in Germany. It's a story of collaboration between different objects. Peter got into astrophotography in 2014, and has steadily developed has talents and equipment ever since. Like most of us, he started with a DSLR, but now uses a dedicated astrophotographic sensor. He also has two triplet refractors that he uses from a fixed pier. The first collaboration is the object itself. Clearly, there are two separate structures here. The red nebula is Sh2-129, or the Flying Bat. The blue nebula is the very recently (2011) discovered Ou4, or the Squid.  Apparently, both occupy the same area in space - one is not behind the other. The only sad part is that you can't see any of this from Australia. The Squid Nebula gets its shape from jets from the triple star system in its middle. The blue shock-waves are rich in ionised Oxygen, which is very dim. It's no surprise that the Squid was only discovered in 2011. In contrast, the Bat is very...

Have a look at this shot of the Carina Nebula. It was taken by our mate Shaun. Shaun has been a photographer for ages, and has a pretty large collection of equipment to prove it. He's mostly been into wildlife and air show photos, but a long-time fascination with things astronomical led him to start his journey into astrophotography last year. Like me, Shaun uses an NEQ6 equatorial mount. Unlike me though, this was his first-ever mount. Clearly Shaun is not one of the faint-hearted. For a telescope, he started with a Sky-Watcher Star Travel 120 doublet refractor (which is the same as a saxon 1206) coupled with a DSLR. It wasn't long before he realised that he wanted to dive into the deep end with narrowband images. He tells me that these can show the wonders that exist in the universe - well beyond what our eyes can see. For the technically minded, the image was taken using a saxon 80mm FCD100 triplet refractor, coupled with a ZWO ASI1600GT. This is a relatively new camera from...

Paul is one of my oldest friends. I was at school with him back in the 1970s. Paul is the lean-in type who has never done anything in a half measure, and is now an accomplished wildlife photographer. Like me, Paul has an interest in astronomy, and has always been fascinated with the idea of photographing the Horsehead Nebula. In order to do this, he got himself a telescope. Showing that lean-in personality again, it's a Celestron 1100 EdgeHD Scmidt-Cassegrain, mounted on a CGEM-II equatorial mount. This is a big scope, and big scopes have complications, as we found. The camera he used is a Nikon D810a, which is specifically for astrophotography, having the built-in IR filter modified to allow longer wavelengths to the sensor. This is important for the Horsehead as it's in a region rich in hydrogen, which emits light at this wavelength. Last week, I went with Paul and his wife Ruth (also a photographer) to the ASV's dark sky site. This was the scope's first...

Our recent competition for wide field astrophotography was won by Clint Conn, and I’ve attached his photo here. Stunning. I’ve taken a few in my time, but never this good. To take a photo like this, you can use a simple tripod and a camera. But you can’t expose for longer than about 30 seconds (depending on your focal length) before you start to get star trails. These can look nice, but if you don’t want them, it’s awful. You have to stop the stars’ apparent motion. A gigantic equatorial mount under your camera would do the job, but that's bulky and expensive. What's worse, your camera would look a bit ridiculous on top of a thumping great machine. You need a simpler and less expensive gadget that tracks the stars. There are several types out there, such as the Sky-Watcher Star Adventurer, or the Vixen Polarie.     You align them to the South Celestial Pole, and once they’re set up, they enable you to take photos of the sky using a camera and a normal lens. To ...