Volume 24 Issue 2 July 2006 The second at lower left has a mid exposue time of 2006-04-27 at 22hr 42min 34sec UT. These being taken as 20 second exposures using a 25cm LX200 S.C. F5.5 at prime focus with a SX-MX916-usb CCD camera. The third at top right was timed at 2006-05-01 with a mid exposure of 21hr 34min 50sec UT. The equipment and exposure times being identical with the first two images. This the comet which broke up into several pieces as reported in the previous issue of Mercury. COMET P/SCHWASSMANN-WACHMANN (73P) he above images of comet P/ Schwassmann-Wachmann (73P) were Ttaken by John Fletcher from his observatory in Tuffley. The first, top left was timed at 2006-04-27 mid exposure time 22hr 39min 32 sec UT. Mercury, July 2006, Volume 24 Issue 2 Page 1 DATES FOR YOUR DIARY the morning sky. By Tony Ireland WEDNESDAY JULY 12th T An interesting line up of Jupiter’s Moons this evening. Ganymede is to the East. Nearer the planet Io and ell, we are back !! Our Skipton property was sold Europa are close whilst normally distant Callisto is mid June and, for the time being we are in Hilary’s W closest to Jupiter. A real traffic jam in line of sight ! flat, almost opposite Christ Church in the centre of Cheltenham, where the church clock does strike three – and all the other hours as well – but there is not much view of the sky at THURSDAY JULY 20th night, thanks to all the trees and bushes. Another opportunity to watch the eternal dance of Jupiter’s Moons. Tonight they are grouped three West, The new house near St. James’ Primary School in The Park one East .Io will be very close to Callisto with Europa is slowly coming along. Yours truly eyes the wide open further out, whilst Ganymede is out to the East. South to North Western sky at the back of this with anticipation, though the Boss has intimated that she requires the ‘observatory’ (!) to be invisible from the house SATURDAY JULY 22 nd B T !! I shall try to oblige. Maybe the BBC has the Tonight Mars will be very close to Regulus in line of odd Tardis hanging around a storeroom it is willing to sell sight. Mars will be at Mag 1.8, just about the dimmest it at a reasonable price …….. can get, whilst Regulus will be brighter at Mag 1.4 to the SSW of Mars. Closest approach will separate them by I hope to attend as many meetings as possible in the future 0.64 degrees at sunset. to renew old friendships and make new ones. Certainly I have been very impressed with all the activities going on THURSDAY JULY 27th T and the diversity of the talks. But we can do more. How For some this is the biggest event of the year !! Before about a Childrens’ Day to encourage youngsters to look at sunset The Moon, just 63.5 hours old, will occult Mars at the sky ? Can it be linked to our own celebrations of 18.52 , 30 degrees above the Western horizon. The planet reaching 25 years later this year ? Are we going to try and will reappear on the bright side of the Moon (!) at 19.44 publicise ourselves for this milestone ? Will there be a when it will be 22 degrees above the horizon. Obviously special dinner with a guest speaker ? Over to you this will be best seen in a large telescope. I hardly imaging …………. binoculars will suffice. Mars will be just 4” across. Meantime in this coming two months we have an occultation of Mars by the Moon and a Lunar eclipse to look AUGUST forward to. So read on and note your diaries accordingly…. TUESDAY AUGUST 1st T As usual events have been annotated with T, B and P to With only Jupiter worth watching in the evening sky you indicate if they are best observed through a telescope, will have to confine your telescopic viewing to its four binoculars or a it’s a photo opportunity. brightest Moons. Tonight they are arranged three East, one West with Io maybe invisible, Europa and JULY 9th to SEPTEMBER 9th Ganymede to the East and Callisto to the West. It’s goodbye to Saturn and Mars as they get closer the Sun, FRIDAY AUGUST 4th T though, whilst Saturn disappears behind the Sun on The Moon occults Star ZC 2383 Mag 2.9 PA 149 at 21..07 August 7th , it takes Mars until October 23rd before it dark side. The Star will emerge from the bright side PA finally does the same. The reason is that our speed vis a 233 at 22.00 BST. vis Mars is such that we maintain parity each ‘side ‘ of the Sun (imaging being in a car travelling in a circle one way Normally I avoid listing events in the morning sky but with a lamp post coming between you and Mars, which is this month I have to mention the line ups of Mercury, travelling in the same direction as you round the circle but Saturn and Venus before sunrise with the added on the other side, much further away from the lamp post. attraction of M44 still in the background. Trouble is that Your movement going to the right of the lamp post is you will need a clear North Eastern horizon, an alarm cancelled out by Mars travelling to the left. clock to wake you up at around 4.30 am (!), and a determination not to turn over and go back to sleep when Jupiter is still well placed for observation. it goes off ! The best week will be the week of August 20th to 27th . Uranus is at opposition on September 5th shining at Mag 5.7. Its tiny blue disc 3.7” across, smaller than Mars (!), will On Tuesday August 22nd wide field binoculars will be at RA 22 57 18 Dec - 7.33. Goto telescopes should be show you a view of Venus, the Moon, Saturn and able to put it in your vision. Good luck ! Mercury in a circle of 7.5 degrees.. from above the horizon. The Beehive Cluster will be higher above Venus. Late in August there is an interesting line up of planets in Mercury, July 2006, Volume 24 Issue 2 Page 2 SEPTEMBER Alan Alan W. Harris THURSDAY SEPTEMBER 7th B P Senior Research Scientist A Partial Eclipse of the Moon tonight. As the Moon Space Science Institute comes up just before just before 8 pm (BST) it will 4603 Orange Knoll Ave. Phone: 818-790-8291 already be in its maximum phase with just a tiny , less La Canada, CA 91011-3364 email: than 1/5th part of the Southern area in darkness. A [email protected] strange sight, worth a photo if you can find an interesting ………………….. horizon. By 20.37 it will be all over. You will need a clear John. very low Eastern horizon to make the best of this. I keep a list of ‘Damocloids’ (a term suggested by Akimasa Nakamura) here: DISCUSSION ON CUBEWANO OBJECT IN KUIPER BELT ftp://ftp.lowell.edu/pub/bas/damocloid th From John Fletcher (17 May) 2002 RP120, which I was pleased to discover one morning, is the latest addition to the group. Hi Roger. For anyone’s interest in the society. Here is a table of ‘Oort cloud asteroids’, or ‘Damocloid’ objects, first built by Akimasa Nakamura <Kuma Kogen, got my answers a few years back following my computed [email protected]>, and added to by me afterwards. Iarcs between 2001 and 2003 on object 2002 RP120. version: 10 Sep 2002 It is STILL listed as a Cubewano: Scattered Disc object: Kuiper belt object in various places. Below the letters I Name H a e i q P got back is today’s data from Guide8 and MPCorb.Dat (5335) Damocles 13.3 11.82 0.87 61.9 1.58 40.6 and below that of my observational times. I note it has a 1996 PW 14.0 323.0 0.99 29.8 2.54 5805 period of 416.24 years. 1997 MD10 16.0 26.96 0.94 59.1 1.54 140 1998 QJ1 16.7 11.44 0.82 23.4 2.11 38.7 At the time of my observations when it was just a bit 1998 WU24 15.0 15.18 0.91 42.6 1.41 59.1 fainter than 15v it was only 1.49-AU from home planet. (20461) 1999 LD31 13.8 24.42 0.90 160.2 2.38 121 * Surely this makes it a comet that perhaps has lost all its gas? * 1999 LE31 12.4 8.16 0.47 151.9 4.31 23.4 (15504) 1999 RG33 12.1 9.51 0.77 35.0 2.15 29.3 Reply from Alan Harris. 1999 TD10 8.8 101.4 0.88 6.0 12.30 1020 2002P120 1999 XS35 17.3 18.06 0.95 19.5 0.95 76.7 Epoch 2002 Sept. 3.0 TT = JDT 2452520.5 MPC 2000 AB229 14.0 52.05 0.96 68.7 2.29 401 M 359.90174 (2000.0) P Q 2000 DG8 12.8 10.75 0.79 129.3 2.19 32.5 n 0.00300896 Peri. 357.66149 +0.76206389 2000 HE46 14.6 21.99 0.89 158.4 2.35 108 +0.33793560 2001 QF6 14.8 7.99 0.72 25.4 2.24 22.6 a 47.5180356 Node 39.17519 +0.60736011 2002 CE10 12.9 8.58 0.78 144.5 1.88 25.1 -0.66873802 2002 RP120 12.4 47.52 0.95 119.0 2.47 328 e 0.9479416 Incl.