Occultation of Saturn by crescent Moon - 16 AprilFirst reports by SPA members |
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Occultation Animations from Worth Hill: David Strange of Dorset has sent us these animated GIF files of the occultation. His observations were made using an Astrovid Camera and a 50cm Newtonian Reflector at the Worth Hill Observatory. The first animation shows the shallow angle at which Saturn disappeared behind the dark limb as seen from Dorset. The second animation shows the planet's spectacular reappearance from behind the bright limb, some 26 minutes later. The third photo is a still image. You can see more of David's excellent work by visiting his website: http://www.dstrange.freeserve.co.uk
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Read all about it! Paul Sutherland managed to set up quickly with a small 40mm scope
on a photographic tripod in the car park of the News International
plant at Wapping, East London. "It was an unsatisfactory way of
doing things, especially with giant lorries revving up nearby
ready to deliver millions of newspapers across the country. I
didn't get accurate timings and in my eagerness to get pictures,
I did not actually see the planet disappear but these shots seem
to capture the immersion. Saturn and the crescent Moon together
were certainly a stunning sight to the unaided eye in the run-up
to the event. In retrospect, I wish I'd just sat and watched the
spectacle, or perhaps taken a few wider angle shots with a conventional
camera and telephoto lens. I missed the reappearance as I had
to get back to work!"
Occultation viewed from South Ockendon: Here's a report from David Jellyman, a first time observer of occultations, who clearly enjoyed himself watching this one! David says: "I observed using my LX90 with a 12.5 mm EP for the disappearance and a 26mm EP for the re-emergence. My timings are indicated below (in UT):
| Disappearance of Titan | 20:53:03 |
| 1st ring touches Moon | 20:59:03 |
| Planet 1st touch | 20:59:28 |
| Planet gone | 21:00:23 |
| Ring gone | 21:00:50 |
| Re-emergence | I missed first appearance (due to looking at incorrect part of moon) |
| Full planet visible | 21:26:43 |
| Full ring visible | 21:27:03 |
The night was quite clear but there was a lot of light pollution.
I was unable to see Titan after the occultation. My location is
South Ockendon in Essex just north of the Thames and quite close
to the meridian. (about 5-6 miles east).
I am a relative beginner and this is the first such occurrence
I have been able to observe. I found it to be quite a fascinating
event. I must now try to get down to the maths to try to work
out exactly what all these timings can tell me."
Well done David - an excellent effort !
Success at Skipton öwell almost! From Skipton, North Yorkshire, a story of success but with an unfortunate twist. Tony Ireland sends this report: "Yippee - what a show ! Saw ingress and egress of Saturn but was too excited to take accurate timings. However I can say that as far as I was concerned it took 61 seconds for Saturn to disappear at around 9.53pm BST. I missed seeing the exact moment of reappearance, as I was fiddling with my video camera, but I did spot most of the reappearance despite some threatening cloud. The resultant video using my Canon M30 does show Saturn at the edge though it disappears well before the sighted viewing in my ETX90. The reappearance is not so clear on video as the focusing was slightly out. At no time is it worth taking a print. And at no time did I spot Titan. I started with my OM1 attached to the ETX and got 2 photos on 1600ASA film at 1/30th of a second. Then the fun began. I thought I had a 36 film but it was a 24 roll. In trying to wind on the film split so I am left with a film on the wrong roller in the camera something I didn't appreciate until I opened the camera so I have probably lost both Moon/Saturn photos! I tried my back up OM40 but the battery was flat! And I didn't have a fast film to put in it anyway and of course no replacement batteries! Never mind, to watch the occultation was a great thrill after all the previous disappointments."
 Robin's image of the Moon closing in on Saturn, above, and a sequence of the planet disappearing from view, below. |
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Great shots from Ickenham: SPA Vice-President Robin Scagell recorded some fine images from Ickenham, Middlesex, despite having to battle to avoid a second occultation - of the spectacle behind a neighbour's house. He used a Nikon Coolpix 880 digital camera through his 21cm f8 reflector. He says: "I only just got it -- the thing was just about to go behind the house and I had to drag the telescope across the lawn twice to get it!"
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The planet about to be occulted by the dark limb. (Click on image to view full size). |
The following ring ansa just about to disappear. (Click to view full size). |
The planet and rings just after reappearance. (Click to view) |
Excellent shots from Essex: Again, Dave Smith, an accomplished asto-photographer from Essex
and the Castle Point Astronomy Club, has taken some terrific views
of the occultation showing the position of the planet in relation
to the Moon from his location. Here are three of them, all showing
the full 4-day old crescent Moon. Dave's equipment consisted of
his 80mm refractor and CP880 digicam. You can see more of his
excellent work by visiting Dave's web-site:
http://www.graviton.demon.co.uk
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Click on the image to view Peter Grego's video of the occultation |
Video from Rednal: Peter Grego, in the West Midlands, recorded a video of the occultation
through a 127mm Maksutov telescope at around 21h 35mUT. Click
on the image above to view it.
 John Fletcher's image shows Saturn's satellites and Earthshine. Click to view full size. |
 Click to view an enlargement of the close-up of Saturn plus satellites. |
Super satellite shots: John Fletcher, of Gloucester, attached a CCD camera to his Meade
LX200 telescope to record not just Saturn but also four satellites
during the event. He writes: "I imaged the complete sequence of
events with the occultation of Saturn by the Moon until it was
behind it completely. The last to vanish was the 10.5 magnitude
satellite Dione. Titan was the first to be occulted. I have 23
25-second exposures of the event. The fact that the dark Earthshine
side was in the CCD frame and not the illuminated side enabled
me to increase the exposure times enough to get the satellites."
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Images from Wales: These excellent images were taken by Brian Woosnam, of Llandrillo,
with a CCD camera. Click on the images to view full size.
Occultation Web Page helps out in Manchester: This interesting piece was sent in to me by Martin Maccragg.
"I knew nothing about the occultation (it was not mentioned in
the Daily Telegraph "The Sky at Night") but, walking home last
night, I noticed this object, which I thought was probably Saturn,
about half a degree from the Moon.
I realised there could be an occultation so I got out my telescope
(an 8?" Dobsonian) and there she(?) was; what I consider to be
the most beautiful planet in the Solar System (apart from Earth)!
A quick search on the web found your site with about half an hour
to go!
The sky was beginning to cloud over but I managed (just) to
see the disappearance. It was too overcast to see Saturn re-appear."
It seems that weather-wise, Manchester was getting up to its old
tricks again, but I'm
glad the information on our web-pages were of help!
And from Wales: Further west, at Caernarfon in Gwynedd, at the very end of the North Wales coast, I was sent a time for the disappearance of the planet behind the earth-lit night hemisphere of the moon. It was sent by Clive Morris who timed the disappearance from his location as 20h 57m UT.
Good Work at Woking: I want to congratulate Joseph Pearson of Woking in Surrey who despite being a new amateur astronomer, has sent me this fine report:
"I am a new member and new to astronomy and as this was my first
ever occultation, I set up my 114 mm reflector well in advance.
My timings from Woking, Surrey are:
| First contact between moon and Saturn | 20:59:50 |
| Disappearance of ring | 21:02:24 |
| Reappearance of ring (some doubt here I think) | 21:24:56 |
| Full emergence of rings | 21:26:15 |
Hope these figures are of some use."
Yes they are, Joseph ! övery well done! I hope you will try to
have a go at some of the fainter objects next.
Retford Report: Michael Clarke, Variable Star Section Director, came down to Earth (for once!) to show an appreciative audience the occultation. He observed from his home in Retford, Nottinghamshire, and this is what Mike had to say:
"The evening of the 16th was all set for a perfect night of observing.
The air was steady and warm, with not one breath of wind. This
was in complete contrast to the early morning of the 23rd February,
when the last lunar occultation of Jupiter took place.
That Jupiter occultation was a learning curve for a CCTV camera
I had just converted for astronomical work. Mistakes from that
event had been learned, and I had my equipment up and running
a good hour before Saturn's disappearance.
My 6 inch F/8 reflecting telescope was tracking perfectly.
The TV monitor was adjusted correctly, and the CCTV images were
very good. For this event I had an audience watching the TV monitor,
and all were impressed with the images. For good measure, I also
had a 70mm F/13 refracting telescope set up for visual observing.
The sight of Saturn and the Moon with 'Earthshine' was simply
wonderful.
My Russian made, Red Army wristwatch had been synchronised,
and it was working with split second accuracy. Ten minutes to
go, and the sky is still clear! Unfortunately, my CCTV camera
was not sensitive enough to record Saturn's moon Titan, so I made
a visual observation with the refractor.
Two minutes to go, and disaster struck. A large rapidly moving
bank of cloud rolled in from the west and covered the Moon! DAMN
!!!, so close and yet beaten at the last minute!
The Moon remained covered for the whole of the disappearance.
Ah well! Such is life! However, we were not giving up! We still
had a chance with the reappearance. With a couple of minutes to
go, the cloud was starting to break up. Success! We had an image
on the screen. Would it last?. Cloud was rolling over the face
of the Moon. Then at 21h 26m 40s UT, a shout goes up: 'There
it is!' The edge of the rings had appeared! We just managed to
see the globe of Saturn reappear, then the screen went
blank, due to cloud. The sky cleared a couple of minutes after
reappearance, and there on the screen was a lovely image of the
Moon and Saturn.
So we had a little bit of success, and the camera proved to
be a great way of sharing
one of nature's free shows with others."
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Highlights from Leeds: My old pal Ray Emery of Leeds sent me a wonderful series of shots
he made of the occultation as seen from Rothwell, to the south
of Leeds. The emergence sequence is from his video, but the others
are taken with his small digital camera afocally through a Helios
150mm f5 refractor. Ray comments that "This was undoubtedly the most beautiful occultation
I have ever seen. I don't expect to see a better one. The earthshine,
plus the position of Saturn against the Moon, made the whole thing
gorgeous. My video went on the blink at immersion, but since there
was no Moon visible against the planet on my view anyway, this
wasn't such a big deal. Exquisite to watch, though öwe had three
scopes going in my back garden! Cloud made the event iffy, but
spared us in the end."
A hit with Titan in Hartlepool: Thanks to Eddie Horsley for the only timing so far I have received of the disappearance of the mag. +8.3 satellite Titan, some 5 minutes prior to the start of the planets occultation. It's a great shame that he wasn't able to get a similar photo-shot of the event as he did early last November. This is what Eddie reports:
"I managed to get an excellent view of the occultation of Saturn, but its reappearance was covered in cloud as seen from my home town of Hartlepool. To me this was a much better glimpse of the event than the one in Nov. 2001. I used my 254mm Dobsonian mounted reflector at f/5.8 , using a magnificationr of X 233, and got fantastic views. I was too busy taking digital photos to get any precise timings (which I then unfortunately deleted as I tried to connect the camera to the PC).The one exact time I did manage was the occultation of the moon Titan, which took place at 20h 43m 45s UT. Watching the moon eat away at the disc give a truly 3-D feeling to the universe in which we play just a tiny part."
Reading timing: Another member, Rob Butler, who lives just to the east of Reading, was impressed by the sight of Saturn disappearing behind the Moon and has this to say about the event:
"Not a terribly scientific report, but after a series of being
clouded out on eclipses, occultations, northern lights, Leonids
etc I finally managed to see something! I'm afraid I don't do
a lot of observing nowadays ötoo old öbut this was a wonderful
sight.
I set a clock to a time signal but I think the cold or damp
got to it so reappearance times were too suspect. However, with
a 10cm reflector I got 9:00:39 UT for the first disappearance
of the Outer Ring and 9:02:10 UT for the disappearance of the
planet as a whole. It seemed as if I could see a faint glow for
a while along the Earthlit edge after the disappearance using
averted vision. My location was Long: 0º 55.25 west and Lat: 51º
25.48 north."
From Long Eaton, Nottingham: A meticulous record of the occultation was sent in by Alan Heath from Nottingham. His report was accompanied as ever by another of his excellent sketches. And I really do appreciate the effort that goes into this type of recording. In these days of CCD and other sophisticated imaging techniques, there is still a place for a sketchbook and pencil. Now, Alan's record of Tuesday night, 2002 April 16: The predicted time of this event was 21h 00.2m for disappearance at Greenwich and 20h 46.6m at Edinburgh. Local predictions were kindly provided by Jon Harper of SPA as: 20h 55m 39s for disappearance and 21h 26m 11s for reappearance.
Conditions: The sky was clear for this event, although there was some broken cloud in the north-east. I could not see the Moon from the observatory, as it was low. I had to use therefore the Celestar-8 in the garden using a magnification of X200.
Photographs: The C-90 Spotterscope was used which is 500mm at f /5.6 and Fuji 200 film was used. The exposure time was 1 second. (We hope eventually, to see Alan's photographs when they are developed.)
Disappearance: 20h 55m 09s Contact with dark limb. The dark
limb was earth-lit.
20h 55m 28 Moon limb reached preceding limb of Saturn.
20h 55m 46s Planet and ring system completely gone,
Reappearance: 21h 27m 00s Planet in full view but rings just in contact with the Moon's bright limb.
Seeing: Rather unsteady throughout; on the Antoniadi Scale of
seeing conditions : 4
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Click to image to enlarge. |
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Saturn shot from Sussex: Terry Pullen from Sussex at Lat: N51.07, Long: W0.323, sent me this wonderful shot of Saturn which accompanies his report: "You asked me to let you know how I got on,. This is a bit after the event, but .... I did manage to catch some images both avi on my web cam and some conventional 35mm through the scope [UK Orion OMC-140 Mak Cass 150mm F14] of the occultation of April 16th. The latter have yet to be processed but I attach a small JPEG of Saturn a minute or so after emerging from behind the Moon. I took 3 or 4 x 15 sec duration avi videos before first contact and after reappearance. The latter were better because of the illuminated limb of the moon but the former turned out to be a problem in that in adjusting gain/exposure/gamma etc. for the web cam I could see Saturn on the laptop screen but not the dark limb of the Moon. Consequently I nearly missed first contact! "
And the moral is! Keith Johnson of Cleveland and Darlington AS sent me this smashing
shot of the post-event appearance of Saturn near to the southern
horn of the waxing crescent. As he explains, he was not so lucky
with the actual occultation.
He tells me: "Here is the result from my image capture. May I
say, before anything else, that I was wanting to capture the event
from my garden (like the Jupiter occultation shots earlier this
year) and do pre-trail runs using all the scopes etc, so as to
minimise the chances of anything going wrong!
On the 16th. however, some astro. associates of mine decided that
we would go to Hamserley Forest in County Durham, and, using a
laptop from a friend of mine, capture the event from there using
an 80mm Vixen F11. ( I took my 120mm refractor up just in case).
We arrived with only 10 mins. to spare. We set up the 'scopes
and camera and then found that the Vixen with the camera wouldn't
focus! By the time I set my scope and camera up, the planet had
gone behind the Moon! So, this is the result of what turned out
to be a nightmare!
If I had stuck with MY idea I would have captured the whole event
from start to finish. So the moral of this story is: if you want
it doing right do it yourself!"
To which I would add that before any occultation work you should
always give yourself plenty of time to make sure that everything
is ready and operational.
Never mind Keith, you DID get this exceptionally good and clear
shot of Saturn close to the moon!
- Jon Harper
- Email: occultation@popastro.com
- Address in Popular Astronomy
- Occultation Section home page
- Email: occultation@popastro.com
Maintained by Email: Last modified 24 August 2002