CalSky has an alert facility and can send daily emails about supernovae, lunar occultations, spacecraft passes and comets. Once of the options if to receive alerts when a satellite or spacecraft crosses the Sun or Moon. July has offered two opportunities to use the crossing alerts to capture some interesting images.

The first came on 5th July when the site predicted a possible occultation of 0.8 magnitude Altair by the International Space Station at magnitude -3.4. Most of the day had been overcast and it was only at 10pm that I decided to go out and watch the event at 22:16:35. On impulse I grabbed a Canon camcorder, put it on a tripod and zoomed in on Altair. With no time to adjust the settings I was surprised that I could get an image of Altair from the twilight and then it was a matter of a few minutes to wait for the ISS and start recording.

The video shows that this was a close pass and not an occultation but I was impressed that video camera was able to capture the event so easily.

The second alert came on 19th July when CalSky predicted that the ISS would cross the disk of Sun. So far this year, I have set up my ETX125 with a solar filter to capture an ISS Sun crossing twice earlier in the year. On the first I was not accurate enough on my timing and did not get any images; on the second cloud rolled in at the last minute. But this time weather conditions were perfect, I was working from home and determined to get the timing right.  

The ETX was tracking the Sun 30 minutes before the event and I had my Canon 350 DSLR on a sports setting to capture multiple images as quickly as possible using a home-built shutter switch. On a quick test I found I could capture about 10 seconds worth of images before writing to the memory card became a problem. Ten seconds gave me about 3 frames per second and so I decided to start firing images 5 seconds before the predicted time. Although I could not see the ISS through the rapidly firing shutter, there were two frames that showed the ISS moving from 4 to 10 o’clock (if the Sun were a clock face).

This approach worked but the sports mode I used gave me no control over the shutter speed or ISO rating. The automatic settings gave an exposure of 1/125 seconds which produced some motion blur, as seen in this scaled up image.

The blurring should not have been a surprise because according to CalSky the angular velocity of the ISS was 56.7′/s and the whole event took place in 0.6 seconds. Next time, I will use a webcam or video camera to try and record the event.

Pointing a telescope or binoculars at the Sun can destroy your eyesight or a digital camera chip. I am very grateful to Society member Chris Thayer for the long term loan of the ETX solar filter which makes my telescope safe for solar viewing.

A sunspot was clearly visible close to the limb surrounded by a brighter region of H-alpha. At the same point on the limb there were a number of promenances very close together.

I tried to image the features using a Celestron 2x Barlow plus an Astro Engineering Imagemate 1.6x magnifier attached to a Canon DSLR. I took a series of exposures at 1/160 second but was unable to bring out the sunspot although the prominences were clear.

I’m not sure if the focus, the tuning of the filter or the exposure was the cause of the problem but the cloud thickened preventing further investigation.

The purchase of the PST was supported by Scopes n Skies but now we have the scope it would be nice to purchase some clear skies!

In the evening Astronomical twilight begins when the sun sinks below the horizon and finishes when the Sun is 18 degrees below the horizon. Likewise, in the morning, twilight begins when the sun is 18 degrees below the horizon and ends at sun rise. These times  are important to astronomers as the twilight sky is not generally dark enough to observe faint objects like Comet C/2009 R1 McNaught which has been present in the early morning Northern skies.  Here in the UK and North of latitude 50 degrees, astronomical twilight lasts all night during midsummer.

Not that  I want to wish the Summer months away! Sunday 27 June 2010 was a fantastic day for lazing around in the Sun, even if England’s departure from the World Cup was a bit of disappointment.

The weather was so nice that I was still sat outside after 10 pm, looking up at the sky and thinking there was little of interest to observe. Arcturus looked brighter and more red than normal, as seen against the light blue of the western sky. The Summer Triangle of Vega, Deneb and Altair had emerged from the twilight putting the limiting magnitude around 2.5 or possibly 3.

However, I was proved wrong about the lack of interesting objects. About 10:26 BST, a bright meteor streaked across the Southern sky leaving a glowing ionisation trail in its path. The radiant appeared to be just below Vega and the end was somewhere in Virgo, towards the horizon.

Although the Moon had not risen sufficiently to have an effect on the ambient light, the twilight made estimating the brightness of the meteor difficult. However, my best estimate is around magnitude -3 or -4 which puts this into the fireball category as used by the Society for Popular Astronomy (SPA).

 This is the time of year for the “June Boötids” an annual shower that occurs when the Earth crosses the orbit of Comet 7P/Pons-Winnecke. This is a short-period comet that orbits the Sun once every 6.37 years.  This is not one of the most spectacular showers with hourly rates of 1 or 2 meteors, although recent unexpected outbursts in 1998 and 2004 saw 50-100 over the course of one night. The SPA quotes the dates of the June Boötids as June 22 to Jul 2 with the peak occurring on the night of June 23 to 24. They also note that in 1998 a further possible maximum was observed on June 27. Other sources (like Wikipedia) quote the dates as June 26 to Jul 2 with the peak occurring on the night of June 27. However, all sources agree on the unpredictable nature of this shower and the fact that most June Boötids are slow moving meteors.

 The radiant and speed of the meteor I observed, suggest that it was a background meteor which did not originate from the June Boötids. I have submitted a report to the SPA and it will be interesting to see if my sighting is verified by other observer’s reports. I hope they can confirm that it truly was a fireball class meteor and whether it could have been a June Boötid.

The instructions were straightforward and the PST worked out of the box with very little adjustment needed to get a clear image of the Sun’s disk. The most frustrating part was the clouds which were slow moving with tantalising gaps which just allowed some time to observe and take some images. The PST has a clever built in alignment tool called the Sol Rangefinder that allows the telescope to be aimed at the Sun. After finding focus with the 12mm eyepiece that ships with the PST, out came the 2x Barlow to step up the magnification. It was easy to bring the Sun into focus as a sharp disk and with a small adjustment of the separate tuning ring on the PST barrel it was possible to see fine details such as sunspots and prominances. 

This picture was taken with a Canon 350 DSLR using a 1.25″ nosepiece and the lens from a Celestron 2x Barlow. It is quite easy to spot the prominances between 6 and 9 o’clock on the clock and these were useful for checking focus.

Using a Canon 350 EOS DSLR exposures of around 1/60 or 1/80 second at ISO800 were enough to capture the filaments but tended to over-expose the fine detail of the sunspots at 11 o’clock on the disk. Sunspots  appear as dark spots surrounded by lighter areas and were distinct on the visual image. There are artifacts in the image that I think result from thin cloud that gives the impression of surface details in the top right quadrant.

The two features mentioned above are expanded in the images below. The Sunspots are not so distinct but there is a lighter “S-shaped” structure attached to the darker spot.

It struck me that although these features look small in the eyepiece, they are planet-sized structures so I added a scale image of the Earth to give a sense of scale.

It takes some time to tune the eye into the features of the solar disk in H-Alpha, but for a first observing session I was well pleased with the experience and pleasantly surprised to capture these images so simply and easily.

Society member Eric Grieve opened up the dome to the afternoon sunshine and talked through the operation of the telescope with members and their guests.

The telescope was positioned to project the Sun safely onto a sheet of cupboard.

Considering the age of the optics, the image of the Sun was relatively clear but there were no sun spots to enjoy!

Despite the fact that the telescope is over 100 years old, the clockwork drive was still able to track the movement of the Sun across the afternoon sky.

Thanks to Adam Thomas for taking the photographs.

The sunset from Lightwater country park was not that spectacular, but the view from Curley Hill did yield a surprise view of Venus and the New Moon emerging from the sunset. 

In this picture Venus is top left and bottom right is the Moon at 1 day and 7 hours old and only 2% of full.

Some credits……

I need to thank my Wife, whose sharp eyes picked out the Moon in the first place, otherwise I would not have stopped so long.

and I want to thank Tony who was also on Curley Hill for the sunset and who was kind enough to lend me the use of his tripod and lens for this shot. Having just gone out to photograph the setting Sun, I was totally unprepared for any astrophotography, so it was lucky for me that we met!

 

Widefield Image of Aquarius – click to enlarge

 

Image taken at an observing evening FAS put on for Beaver Scouts at Garners Field Scout Camp Site, Tilford, Farnham, Surrey, 24 October at 21:34. 

Unguided 20 second exposure at ISO1600 using 18mm lens on a Canon EOS350 digital SLR.  Some post-processing to using the curves tool to adjust the colour levels and enhance the contrast in the sky

Looking South towards Hindhead and Haslemere, just after the Moon had set behind the hills.   At magnitude -2.1, Jupiter was the brightest object in the sky, just to the North of Capricorn.  But with the aid of Stellarium I found I had also captured Uranus at magnitude 5.9.  Neptune and the minor planet Juno, were in the same field of view, but at magnitude 7.8 the exposure wasn’t long enough to capture them on the image. 

Widefield Image of Aquarius (annotated) - click to enlarge

Stellarium screenshot of Aquarius – click to enlarge

 

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Stellarium Screenshot of Saggitarius Ophiuchus Lyra

 Image taken at an observing evening FAS put on for Beaver Scouts at Garners Field Scout Camp Site, Tilford, Farnham, Surrey, 24 October at 21:42

 Unguided 20 second exposure at ISO1600 using 18mm lens on a Canon EOS350 digital SLR.

Some post-processing to using the curves tool to adjust the colour levels and enhance the contrast in the sky

Looking West towards Alton.  To the left of the image Altair is clearly visible at magnitude 0.7 and to the right is Vega At magnitude zero (Magnitudes taken from Stellarium)

Stellarium Screenshot of Saggitarius Ophiuchus Lyra - click to enlarge

Image taken at an observing evening FAS put on for Beaver Scouts at Garners Field Scout Camp Site, Tilford, Farnham, Surrey.  24 October at 21:34

Widefield Image of Cassiopiea and Andromeda - click to enlarge

Unguided 20 second exposure at ISO1600 using 18mm lens on a Canon EOS350 digital SLR.  Some post-processing using the curves tool to adjust the colour levels and enhance the contrast in the sky.

The camera was pointing almost directly overhead at the Milky way through Cassiopeia.

The field of view is rich with deep sky objects but the limited exposure only captured the brightest objects.  Within this field of view are:

• The constellation Andromeda (And)
• The constellation Cassiopeia (Cas)
• Part of the constellation Cepheus (Cep)
• Part of the constellation Camelopardalis (Cam)
• Part of the constellation Lacerta (Lac)
• Part of the constellation Pegasus (Peg)
• Part of the constellation Perseus (Per)
• Part of the constellation Pisces (Psc)
• NGC 7822
• NGC 224 / Great Nebula in Andromeda / M 31
• NGC 598 / M 33 / Triangulum galaxy
• IC 1805
• IC 1848

M32 The Andromeda Galaxy, also known as Messier 31 (M31) or NGC 224 is a spiral galaxy approximately 2.5 million light-years from Earth. Seen in the constellation Andromeda, it is the nearest spiral galaxy to our own Milky Way. As it is visible as a faint smudge in a dark sky, it is one of the most distant objects visible to the naked eye. M31 is estimated to contain one trillion stars, more than twice the 200-400 billion in our own galaxy but due to the presence of dark matter n the Milky Way their masses are thought to be approximately equal.

Open clusters NGC 869 and NGC 884 are bright enough to be seen from a dark location without even binoculars. Although their discovery probably predates written history, but the Greek astronomer Hipparchus (190 to 120 BC) did catalog what we now call the “double cluster”. The clusters are more than 7000 light years from Earth, toward the constellation of Perseus and they are separated by a few hundred light years.

Widefield Image of Cassiopiea and Andromeda – annotated – click to enlarge

Stellarium Screenshot – click to enlarge

At the October FAS meeting, John Price showed some interesting videos regarding recent satellite and spacecraft missions involving the European Space Agency (ESA). One of the videos covered the Automatic Transfer Vehicle (ATV).   The ATV is an expendable, unmanned resupply spacecraft, designed to supply the International Space Station (ISS) with fuel, water, air and equipment. In addition, the ATVs can boost the station into a higher orbit and carry away waste to burn up with the vehicle during re-entry.

The first ATV, “Jules Verne”, was launched in March 2008 and ESA has already contracted suppliers to produce four more to be flown until 2015.

John’s video reminded me that I captured an image of the ATV and the ISS while the ATV was on it’s maiden flight and testing the docking maneuvers. Whilst I had imaged the ISS alone several times, this was the first time I captured two craft in the same image.

ISS and ATV – Click to expand

The above image was captured with a 20 second exposure at ISO400 taken with an 18mm lens on a Canon EOS350 digital SLR.

 H-II Transfer Vehicle (HTV)

 The H-II Transfer Vehicle (HTV) is an unmanned resupply spacecraft, similar to the ATV, designed to resupply the Kibo- Japanese Experiment Module (JEM) which is part of the International Space Station (ISS). The Japan Aerospace Exploration Agency (JAXA) has been working on the design since the early 1990s. The first mission, HTV-1, was originally intended to be launched in 2001 but finally lifted-off on September 10, 2009. I wanted to capture an image of the HTV and the ISS in the same field of view. Unfortunately the weather and timing of the orbits meant I had to settle for two separate shots while the HTV was playing catch up with the ISS.

ISS and H-II Transfer Vehicle (HTV) – click to enlarge

The image was captured with a 20 second exposure at ISO400 taken with an 18mm lens on a Canon EOS350 digital SLR.

ISS and STS119

In the Summer of 2008 I went out to watch the International Space Station (ISS) flyover and saw another object travelling about two seconds behind it. On checking http://www.heavens-above.com I realised that I had been watching the Space Shuttle catch up with the ISS in orbit. This was a surprise to me as I did not know that the shuttle could be seen with the naked eye. I set myself the target of capturing an image of the ISS and a shuttle in the same field of view. I had to wait until Shuttle mission 119 (STS119) which was launched in March 2009 to equip the International Space Station with new solar panels and equipment to allow for the crew to be expanded. I managed to get this image shortly after STS119 left the ISS as the two craft flew through Orion’s belt. Although they were almost a minute apart, this was the first time I caught two manned craft in the same image.

 The capture process was complicated by the fact I was taking a Scout Group through their Astronomy badge and I had 20 excited Scouts and leaders gathered around the camera. It also meant I had to take the shot from the Scout hut which did not afford a clear view of the sky.

ISS and STS119 – click to enlarge

The image was captured with a 20 second exposure at ISO400 taken with an 18mm lens on a Canon EOS350 digital SLR.