cmpbsdb@gitpyr.UUCP (Don Barry) (12/28/85)
Here are January's currently known bright comets. Predictions are
every fourth day for first even hour after comet-rise. Motion
is generally slow, so these are sufficient to chart its movement
in an atlas to find the objects with binoculars or telescopically.
Brightnesses are only rough estimates and the actual brightness
may vary considerably.
Bonne Chance,
Don Barry
N.B. Predictions are for Atlanta, but RA and DEC are valid everywhere,
and AZ/EL are approximately valid if you use your local time and
are in the U.S.
COMET EPHEMERIS FOR ATLANTA
FROM 06:28 PM EST, WEDNESDAY, 01 JANUARY, 1986 UNTIL 06:53 AM EST
TIME(EST) AZ EL RANGE LHA RA/1950 D/1950 HDG MAG
07:00:00 PM 237.4 35.4 01.18 02:53.8 22:12.4 -02D49 248 +04.6
HALLEY'S COMET D/D=0.55
07:00:00 PM 262.8 27.4 01.84 04:12.7 20:53.6 +09D15 221 +10.3
COMET THIELE (1985M) D/D=0.10
04:00:00 AM 079.7 01.6 01.10 17:42.5 16:25.4 +09D31 229 +06.8
HARTLEY-GOOD D/D=0.64
COMET EPHEMERIS FOR ATLANTA
FROM 06:31 PM EST, SUNDAY, 05 JANUARY, 1986 UNTIL 06:54 AM EST
TIME(EST) AZ EL RANGE LHA RA/1950 D/1950 HDG MAG
07:00:00 PM 265.0 23.7 01.92 04:29.8 20:52.3 +08D52 221 +10.4
COMET THIELE (1985M) D/D=0.08
07:00:00 PM 241.7 30.3 01.25 03:18.4 22:03.6 -03D42 248 +04.3
HALLEY'S COMET D/D=0.50
04:00:00 AM 084.3 05.6 01.08 18:06.0 16:17.6 +07D54 228 +07.0
HARTLEY-GOOD D/D=0.67
COMET EPHEMERIS FOR ATLANTA
FROM 06:34 PM EST, THURSDAY, 09 JANUARY, 1986 UNTIL 06:54 AM EST
TIME(EST) AZ EL RANGE LHA RA/1950 D/1950 HDG MAG
07:00:00 PM 245.5 25.4 01.32 03:42.1 21:55.6 -04D29 248 +04.0
HALLEY'S COMET D/D=0.48
07:00:00 PM 267.2 20.1 02.00 04:46.6 20:51.3 +08D34 223 +10.6
COMET THIELE (1985M) D/D=0.06
04:00:00 AM 089.0 09.5 01.06 18:29.5 16:09.9 +06D11 228 +07.3
HARTLEY-GOOD D/D=0.70
COMET EPHEMERIS FOR ATLANTA
FROM 06:37 PM EST, MONDAY, 13 JANUARY, 1986 UNTIL 06:54 AM EST
TIME(EST) AZ EL RANGE LHA RA/1950 D/1950 HDG MAG
07:00:00 PM 248.9 20.4 01.39 04:05.3 21:48.2 -05D14 247 +03.7
HALLEY'S COMET D/D=0.47
07:00:00 PM 269.3 16.5 02.07 05:03.2 20:50.4 +08D20 226 +10.7
COMET THIELE (1985M) D/D=0.05
03:00:00 AM 085.5 00.9 01.03 17:53.0 16:02.0 +04D22 228 +07.6
HARTLEY-GOOD D/D=0.75
COMET EPHEMERIS FOR ATLANTA
FROM 06:41 PM EST, FRIDAY, 17 JANUARY, 1986 UNTIL 06:53 AM EST
TIME(EST) AZ EL RANGE LHA RA/1950 D/1950 HDG MAG
07:00:00 PM 251.9 15.5 01.44 04:28.2 21:41.1 -05D57 247 +03.4
HALLEY'S COMET D/D=0.47
07:00:00 PM 271.4 12.9 02.13 05:19.7 20:49.7 +08D09 233 +10.9
COMET THIELE (1985M) D/D=0.04
03:00:00 AM 090.4 04.9 01.00 18:17.2 15:53.5 +02D26 229 +07.8
HARTLEY-GOOD D/D=0.80
COMET EPHEMERIS FOR ATLANTA
FROM 06:44 PM EST, TUESDAY, 21 JANUARY, 1986 UNTIL 06:52 AM EST
TIME(EST) AZ EL RANGE LHA RA/1950 D/1950 HDG MAG
07:00:00 PM 254.8 10.5 01.49 04:50.9 21:34.1 -06D40 246 +03.1
HALLEY'S COMET D/D=0.48
07:00:00 PM 273.5 09.5 02.19 05:36.1 20:49.1 +08D01 244 +11.0
COMET THIELE (1985M) D/D=0.03
03:00:00 AM 095.6 08.9 00.97 18:42.0 15:44.4 +00D24 231 +08.1
HARTLEY-GOOD D/D=0.87
COMET EPHEMERIS FOR ATLANTA
FROM 06:48 PM EST, SATURDAY, 25 JANUARY, 1986 UNTIL 06:51 AM EST
TIME(EST) AZ EL RANGE LHA RA/1950 D/1950 HDG MAG
07:00:00 PM 257.5 05.5 01.53 05:13.7 21:27.1 -07D25 244 +02.8
HALLEY'S COMET D/D=0.49
07:00:00 PM 275.7 06.0 02.24 05:52.3 20:48.6 +07D55 260 +11.1
COMET THIELE (1985M) D/D=0.02
02:00:00 AM 092.6 00.5 00.94 18:07.5 15:34.5 -01D43 232 +08.3
HARTLEY-GOOD D/D=0.95
COMET EPHEMERIS FOR ATLANTA
FROM 06:51 PM EST, WEDNESDAY, 29 JANUARY, 1986 UNTIL 06:49 AM EST
TIME(EST) AZ EL RANGE LHA RA/1950 D/1950 HDG MAG
07:00:00 PM 260.1 00.4 01.55 05:36.6 21:20.0 -08D12 243 +02.5
HALLEY'S COMET D/D=0.50
07:00:00 PM 277.9 02.6 02.28 06:08.6 20:48.1 +07D52 278 +11.3
COMET THIELE (1985M) D/D=0.02
02:00:00 AM 098.2 04.9 00.91 18:34.4 15:23.4 -03D58 234 +08.5
HARTLEY-GOOD D/D=1.04
--
Don Barry (Chemistry Dept) CSnet: cmpbsdb%gitpyr.GTNET@gatech.CSNET
Georgia Institute of Technology BITNET: CMPBSDB @ GITVM1
Atlanta, GA 30332 ARPA: cmpbsdb%gitpyr.GTNET%gatech.CSNET@csnet-relay.ARPA
UUCP: ...!{akgua,allegra,amd,hplabs,ihnp4,seismo,ut-ngp}!gatech!gitpyr!cmpbsdbjwg@teddy.UUCP (12/30/85)
> COMET EPHEMERIS FOR ATLANTA > FROM 06:28 PM EST, WEDNESDAY, 01 JANUARY, 1986 UNTIL 06:53 AM EST > > TIME(EST) AZ EL RANGE LHA RA/1950 D/1950 HDG MAG > 07:00:00 PM 237.4 35.4 01.18 02:53.8 22:12.4 -02D49 248 +04.6 > HALLEY'S COMET D/D=0.55 > 07:00:00 PM 262.8 27.4 01.84 04:12.7 20:53.6 +09D15 221 +10.3 > COMET THIELE (1985M) D/D=0.10 > 04:00:00 AM 079.7 01.6 01.10 17:42.5 16:25.4 +09D31 229 +06.8 > HARTLEY-GOOD D/D=0.64 > Could someone explain where to look in the sky to find these coordinates. Thanks. -- Jim Galbiati, GenRad Inc, Production Test Division Mail Stop 6, 300 Baker Ave, Concord, Mass. 01742 {decvax,linus,wjh12,mit-eddie,cbosgd,masscomp}!genrad!panda!jwg (617) 369-4400 x2459
wyatt@cfa.UUCP (Bill Wyatt) (12/31/85)
> > COMET EPHEMERIS FOR ATLANTA > > FROM 06:28 PM EST, WEDNESDAY, 01 JANUARY, 1986 UNTIL 06:53 AM EST > > > > TIME(EST) AZ EL RANGE LHA RA/1950 D/1950 HDG MAG > > 07:00:00 PM 237.4 35.4 01.18 02:53.8 22:12.4 -02D49 248 +04.6 > > HALLEY'S COMET D/D=0.55 ..... > > Could someone explain where to look in the sky to find these coordinates. > Thanks. > -- > Jim Galbiati, GenRad Inc, Production Test Division Since AZ (azimuth) and EL (elevation or altitude) are given, these are the easiest to use. Zero degrees azimuth is due north, increasing to the east (= 90). Since 270 degrees is due west, 237.4 degrees is WSW more or less. Elevation is just that: the angle above the horizon at the given azimuth, in this case 35 degrees. As the earth rotates, these coordinates will change rather quickly, so they are valid only at the given time and place (see discussion of RA and Dec, below). BTW, astronomers used to (something like longer than 30 years ago, I think) measure azimuth from the south, not the north. Right ascension and declination (the RA/1950 and D/1950 in the line above) refer to a coordinate on the celestial sphere and are analogous to longitude and latitude. The zero point of declination is the celestial equator, and is measured in + and - degrees, just as for latitude. For RA, the zero point is the `first point of Aries', and is measured in hours of time (1 hour = 15 degrees) and is measured increasing to the east, so that stars passing overhead later in the night have a greater RA that those that passed overhead earlier. (Except that 24 hours wraps around to 0 hours again). At one time the zero point was in Aries. Now it's in Pices, heading for, and nearly into Aquarius, hence `Age of Aquarius'. For stars, RA and dec do not change, to first approximation. The RA and dec coordinate system is apparently tilted relative to the Az/Alt system for any observer not at the north pole, so the Az/Alt coordinates change quickly as a star rises. Precession of the earth's pole (a 17,000 year cycle) does alter the coordinate system, however, so all coordinates are given as they were in 1950.0, also known as the epoch. Some observatories are now converting to 2000.0 coordinates, and everybody plans to sometime. Solar system objects, such as comets, are so nearby as to have an appreciable angular speed relative to the earth, so their RA and Dec change also, albeit more slowly than Az/Alt. For this reason, the RA and Dec given above are also only good for the time stated. For a quick sky reference, the westernmost star in Cassiopea is near 0 hours, so a line between it and the pole star can be extended to define the zero point. The Great Square of Pegasus (which Halley was near for a while) is close to one hour or 15 degrees on a side, and the two easternmost stars are also near 0 hours (thus extending the line). Last, the top star in Orion's belt is on the celestial equator. Remember that the lines of RA converge to the north pole, just like longitude, and so are curved relative to declination. -- Bill UUCP: {harvard,genrad,allegra,ihnp4}!wjh12!cfa!wyatt Wyatt ARPA: wyatt%cfa.UUCP@harvard.ARPA