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Ever seen the Zodiacal Light ?

September 29, 2011 Leave a comment

No, me neither until this morning. I was reading Bob Kings excellent Astro Bob astronomical blog http://astrobob.areavoices.com/ and the entry for yesterday happened to discuss the autumn phenomena called the Zodiacal Light http://astrobob.areavoices.com/2011/09/28/comet-honda-visits-the-ghost-of-comets-past/  This faint, low,  roughly triangular glow of light, best seen in the east just before morning twilight, represents the reflected light from cosmic dust which has gathered on the ecliptic plane. The ecliptic plane is slightly tilted upward at this time of year which makes it more visible, particularly when the moon is absent. This interplanetary dust lies in a lens shaped band centered around the sun and extending out beyond Earth’s orbit. The dust is commonly thought to derive from the trail of comets passing through the solar system. I had a look this morning and there was certainly a very faint and high glow extending up at least 45 degrees into the sky when looking east around 6-6.30 am. I didn’t have the DSLR with me at the time but later on I thought I would have a look at the fisheye weather cams for the GRAS telescope in New Mexico and sure enough a faint triangular glow in the east was clearly discernible. Take a look at the image below and if you can see a faint wedge of light shooting up above the pole at the bottom of the image toward the Milky Way – that is the Zodiacal Light !

Categories: Comets, General

A Return to the Hobby

Well, its pouring with rain and blowing a gale outside so this seemed the right time to start up a diary of my recent return to amateur astronomy after 25 years. Why so long away from the subject ? Well astronomy was never completely ignored over that time and I always kept up with the latest events via astronomy magazines, the news and the internet. I even occasionally made observations with the naked eye or a pair of 10×50 binoculars (I will never forget the joys of seeing Comet Hale Bopp above the house we rented in Montgomery over the Winter of 1996/7, the total solar eclipse of August 1999, the many lunar eclipses and numerous meteors). But somehow the common pressures of life and financial circumstances never permitted me to pursue the hobby in any depth and most of all I lacked a decent telescope!

Where did the interest start? Well of course I saw the first lunar landing on the moon in 1969 on our small black and white TV, but strangely that never seemed to trigger much interest at the time in going outside and observing, perhaps because I was only 5 years old! Much later, it must have been 1977 or 1978, I will never forget the night I was out in the back garden of my parents house near Ponterwyd in mid Wales. Looking north I saw a huge fireball streak across the sky and disappear out over the Irish Sea. It was so large it even produced an audible sonic shock wave as it entered our upper atmosphere. I wasn’t sure what I had seen and wanted to let people know about it so I joined the Society for Popular Astronomy (SPA) and reported it to the Meteor Section. Next month a newsletter came through and my fireball was reported under my own name. I was so excited that I had actually contributed something that I was hooked.

I last used a telescope back in 1982. I had a very basic Tasco 4″ reflector with a few poor quality eyepieces (I am sure some of the lenses were plastic!) , a few filters and a wobbly wooden tripod supporting a manually driven equatorial mount. As lowly as this equipment may have been between 1980 and 1983 that telescope let me see many superb objects including the Moon, Saturn’s rings and Jupiter’s great red spot with a few of the moons of both these planets, Venus, Mars and numerous stars and star clusters. I developed a particular interest in the Sun, perhaps because it changes every day and there is always something new to see on its surface or circumference. I joined the SPA’s Solar Section and by projecting its image onto an old cine projection screen I recorded the changing sunspots and surrounding features, sent the records in and even occasionally got mentioned in the sections newsletter.

I distinctly remember one momentous day which may have ended my observations for good. I had been projecting the sun in the normal way via an eyepiece protected by a glass sun filter screwed into it. I had looked up at the projection screen and was returning to the telescope when I heard a very brief glassy ‘chink’. Looking at the eyepiece sunlight was pouring out of the lens. The solar filter had cracked with the intensity of the focussed sun’s heat!! If I had returned to the eyepiece seconds earlier I might have been totally blinded in the right eye. Of course now it is common knowledge that these cheap glass eyepiece filters are dangerous and should never be used, but back in 1981/2 this was not widely recognised and there were few warnings for the unwary amateur.

After I left home for university the Tasco telescope was sold and developing a career in one of my other main interests, archaeology, took over. In July 2007 I took the plunge and bought some good quality astronomy kit that will last the rest of my lifetime and set off on a new voyage of discovery.

Categories: General