liss@psyche.DEC (Frederick R. Liss 237-3649) (05/21/85)
I finally got a chance to compare the output of the Comet Halley ephemeras program distributed by Mr. Dibbell, to published figures in Sky & Telescope magazine. Even though there is a slight difference in RA and declination, the agreement is close enough for the amateur astronomer. I tend to trust the values for magnitude supplied by the program since the S&T values vary widely from month to month and are sometimes followed by a (?). Regards, Fred --- Frederick R. Liss UUCP ...decvax!decwrl!dec-rhea!dec-psyche!liss Digital Equipment Corp. ARPA liss%psyche.DEC@decwrl.ARPA 333 South St. Shrewsbury MA, 01545 Mail Stop SHR-4/D21 [LONG TABLE FOLLOWS] FROM PROGRAM FROM SKY AND TELESCOPE ------------------------------ Data For Comet Halley DATE: M/D/Y = 4/25/1985 Days to perihelion: -291 Coordinates: RA: 4 HRS 56 MIN 4 59.0 DEC: 15 DEG 55 MIN 15 58 Distances: Comet To Sun: 4.174 AU Comet To Earth: 4.91 AU Predicted Mag.: 15.3 18 ------------------------------ Data For Comet Halley DATE: M/D/Y = 5/5/1985 Days to perihelion: -281 Coordinates: RA: 5 HRS 0 MIN 5 02.8 DEC: 16 DEG 20 MIN 16 23 Distances: Comet To Sun: 4.071 AU Comet To Earth: 4.91 AU Predicted Mag.: 15.2 18 ------------------------------ Data For Comet Halley DATE: M/D/Y = 5/15/1985 Days to perihelion: -271 Coordinates: RA: 5 HRS 5 MIN 5 07.3 DEC: 16 DEG 43 MIN 16 46 Distances: Comet To Sun: 3.966 AU Comet To Earth: 4.89 AU Predicted Mag.: 15 18 ------------------------------ Data For Comet Halley DATE: M/D/Y = 5/25/1985 Days to perihelion: -261 Coordinates: RA: 5 HRS 10 MIN 5 12.4 DEC: 17 DEG 6 MIN 17 09 Distances: Comet To Sun: 3.86 AU Comet To Earth: 4.84 AU Predicted Mag.: 14.9 18 ------------------------------ Data For Comet Halley DATE: M/D/Y = 6/4/1985 Days to perihelion: -251 Coordinates: RA: 5 HRS 16 MIN 5 18.0 DEC: 17 DEG 27 MIN 17 29 Distances: Comet To Sun: 3.753 AU Comet To Earth: 4.77 AU Predicted Mag.: 14.7 18 ------------------------------ Data For Comet Halley DATE: M/D/Y = 6/14/1985 Days to perihelion: -241 Coordinates: RA: 5 HRS 22 MIN 5 24.1 DEC: 17 DEG 46 MIN 17 48 Distances: Comet To Sun: 3.644 AU Comet To Earth: 4.67 AU Predicted Mag.: 14.5 16? ------------------------------ Data For Comet Halley DATE: M/D/Y = 6/24/1985 Days to perihelion: -231 Coordinates: RA: 5 HRS 28 MIN 5 30.4 DEC: 18 DEG 3 MIN 18 05 Distances: Comet To Sun: 3.534 AU Comet To Earth: 4.54 AU Predicted Mag.: 14.3 16? ------------------------------ Data For Comet Halley DATE: M/D/Y = 7/4/1985 Days to perihelion: -221 Coordinates: RA: 5 HRS 35 MIN 5 37.0 DEC: 18 DEG 18 MIN 18 20 Distances: Comet To Sun: 3.422 AU Comet To Earth: 4.38 AU Predicted Mag.: 14.1 16? Posted: Tue 21-May-1985 13:27 To: RHEA::DECWRL::"net.astro"