The following data has been provided by
Royston Deanof
The Astronomy Resource Centre
MAIN ROAD, HAWKWELL, HOCKLEY, ESSEX, SS5 4JH
01702-206244
Hawkwell is on the B1013
Please ring at the beginning of the month if you would like a further newsletter.
OBSERVATIONAL
SESSIONS are held here on clear evenings, pre-booked.
Free of charge. Use our telescopes.
The Astronomy Learning Centre is a cross between an evening class and a club and is intended especially for anyone who is just starting on the subject and would like to know more. Meetings are very informal and friendly.
Venue is
at Fitzwimarc School, Hockley Road, Rayleigh, 7.30 to 9 p.m.
Meetings once
or twice a month on a Monday evening.
. Next are on 13th
and 27th March and 10th April.
Call for details.
A star map is at the bottom of this page
ASTRONOMY
APRIL 2006
The Partial Eclipse of the Sun which took place on the 29th March was a great success and continued our run of observing all events concerning the Sun since the near Total Eclipse (from here) of 1999. The whole week was windy, cold and mainly cloudy but the Wednesday morning was a mixture of good clear spots between broken cloud and a much lighter wind. Using an adapted Tal-1 reflector there was a clean projected image of the Moon’s passage across the lower part of the Sun’s disc. A couple of sunspot groups could be made out above the obscured area although quite faint and difficult to see on the projection. The next Partial Eclipse will be on 1st August 2008 with a cover of 22 percent.
The Eclipse took place between 10.45a.m. and 12.22p.m.
NOTE: Never look at the Sun directly as you may damage your eyes. Special glasses or filters made specifically for observing the Sun with the correct CE mark can be obtained from dealers. If unsure – don’t do it.
Venus continues to be in the morning sky for most of the year and rises a good hour before the Sun during April. The brightest of all the planets at just over minus 4 magnitudes so can be seen in strong twilight or even full daylight. However for the next few weeks especially it remains low in the east/southeast so a good horizon is needed to spot this bright point. Telescopically Venus is about half phase and quite small.
Mars is now moving well to the west due to the changing seasons but is resisting by continuing to move slowly against the background stars eastwards. From its position close to the Pleiades back in February it lies between Taurus and Gemini during early April continuing well into the twins by the end of the month. Its brilliance of last year has now faded to around or just below that of the brightest stars. Best to find Mars mid to late evening before it sinks too low in the west. Very small in telescopes.
Jupiter is slowly trying to get into our evening skies and should be visible very low in the east late evening well below Bootes. By the end of the month rising time will have increased to around sunset so will be visible as darkness falls. Unfortunately planets which appear during the Spring/Summer period have a fairly low track so although Jupiter will be the brightest starlike point around at minus 2 magnitudes it will have a track much lower than that of Saturn. Again a good east/south horizon would be an advantage. Telescopically Jupiter is one of the best planets to observe, despite its great distance from us, due to its large size. At least a couple of dark cloud belts should be seen crossing the disc together with its four largest moons. These moons, Io, Europa, Ganymede and Callisto are virtually small planet size in their own right but we can only see them as faint dots in line with the planet’s equator. Their positions relative to each other and Jupiter itself can change within short periods and some may not be visible at all as they can be hidden by the planet.
Saturn is still the best placed this month remaining close to the star cluster Praecepe, M44, at the centre of Cancer. At around magnitude 0 it is still slightly brighter than the brightest stars in the area. Telescopically it is still giving excellent views of the ring system and its largest moon Titan which appears as a starlike point.
A lot of interest was shown in the Moon last month due to the two eclipses but as it is the nearest celestial body to us we can see features on its surface very well even with small telescopes or binoculars. The best observing time is from the crescent stage up to a day or so before Full Moon. During the First Quarter phase for instance the sunlight is at a low angle and casts shadows in and around the craters and mountainous regions especially along the Terminator, the rough line between the light and dark side. The Moon’s surface is a very rugged place and with low Sun angles giving good contrast fine detail is easy to make out. Many of the larger craters have at least one central peak whose shadow can sometimes be seen stretching across the crater floor. Around Full observation is difficult as the sunlight is falling directly into the nooks and crannies of the craters giving the landscape a brilliant glare, filters can help but the contrast is lost.
We have a Meteor Shower later in the month.
The Lyrid shower begins to throw meteors at us on the 19th and continues until the 25th, a short period with not usually great numbers but the peak should be due in the afternoon of the 22nd which does present a slight problem. I would therefore be inclined to observe on the evenings of 21st/22nd and 22nd/23rd. Some years we have encountered larger numbers of meteors which have given very good displays, the trouble is there is no way of telling when these will be so we have to just keep on looking.
The International Space Station (ISS) can be seen late evening or early morning and is easily seen with the naked eye as it passes over together with the Space Shuttle at certain times.
NASA only give out a few predictions at a time so if you have access to the Internet, try NASA website:
http://www.spaceflight.nasa.gov/realdata/sightings/ then click on skywatch, or call me for timings over the phone.
MOON First Quarter 5th Full Moon 13th Last Quarter 21st New Moon 27th
