mr magellan Posted June 7, 2004 Posted June 7, 2004 Hello all i noticed to day on my garmin gpsmap 60c that on my sun and moon page that i have the proper date and time and my location enabled i have the sunrise time and sunset time and and moonset time but no moonrise time what gives thanks Quote
Neo_Geo Posted June 7, 2004 Posted June 7, 2004 (edited) Your GPS is working perfectly! That means that the moon did not and will not rise on June 6th. Moonrise and moonset is roughly every 24 and 3/4 hours. On June 5th it rose at 11:44 PM. It will not rise again June 7th at 12:28 AM. Edited June 7, 2004 by Neo_Geo Quote
stevesisti Posted June 7, 2004 Posted June 7, 2004 Hello all i noticed to day on my garmin gpsmap 60c that on my sun and moon page that i have the proper date and time and my location enabled i have the sunrise time and sunset time and and moonset time but no moonrise time what gives thanks There are certain days when the moonrise doesn't happen exactly within a 24 hr period, and actually happens a short time into the "next day", so the Moonrise field for that day will be blank. I believe the same can happen with the moonset also. Moonrise and moonset tables show these oddities also, so I believe your unit is behaving corectly. Today happens to be one of those days, as you can see from the naval observatory table below. The moonrises are on the preceeding and the following morning U.S. Naval Observatory Astronomical Applications Department Sun and Moon Data for One Day The following information is provided for Piermont, Rockland County, New York (longitude W73.9, latitude N41.0): Sunday 6 June 2004 Eastern Daylight Time SUN Begin civil twilight 4:51 a.m. Sunrise 5:24 a.m. Sun transit 12:54 p.m. Sunset 8:25 p.m. End civil twilight 8:59 p.m. MOON Moonrise 11:40 p.m. on preceding day Moon transit 4:12 a.m. Moonset 8:49 a.m. Moonrise 12:23 a.m. on following day You can double check yourself here, http://aa.usno.navy.mil/data/docs/RS_OneDay.html Quote
mr magellan Posted June 7, 2004 Author Posted June 7, 2004 (edited) Thanks for your help guys cheers Larry Edited June 7, 2004 by mr magellan Quote
stevesisti Posted June 7, 2004 Posted June 7, 2004 (edited) Your GPS is working perfectly! That means that the moon did not and will not rise on June 6th. Moonrise and moonset is roughly every 24 and 3/4 hours. On June 5th it rose at 11:44 PM. It will not rise again June 7th at 12:28 AM. Actually moonrise and moonset is not "every 24 3/4 hours". On the 16th of this month (and many other days) they both happen in one day within 16 hrs of each other. See the chart below. I believe your 24 3/4 hour figure is the time it takes the earth to rotate to the point where the moon is again aligned with the earth. Since the moon traveled through it's orbit while the earth was rotating, the "extra" 3/4 hour is needed to "catch up" to where the moon moved to. This would explain the tidal time "ADVANCE" on a daily basis. U.S. Naval Observatory Astronomical Applications Department Sun and Moon Data for One Day The following information is provided for Piermont, Rockland County, New York (longitude W73.9, latitude N41.0): Wednesday 16 June 2004 Eastern Daylight Time SUN Begin civil twilight 4:49 a.m. Sunrise 5:23 a.m. Sun transit 12:56 p.m. Sunset 8:30 p.m. End civil twilight 9:04 p.m. MOON Moonset 6:53 p.m. on preceding day Moonrise 4:12 a.m. Moon transit 11:59 a.m. Moonset 7:54 p.m. Moonrise 4:50 a.m. on following day Edited June 7, 2004 by stevesisti Quote
+Stunod Posted June 7, 2004 Posted June 7, 2004 (edited) Your GPS is working perfectly! That means that the moon did not and will not rise on June 6th. Moonrise and moonset is roughly every 24 and 3/4 hours. On June 5th it rose at 11:44 PM. It will not rise again June 7th at 12:28 AM. Actually moonrise and moonset is not "every 24 3/4 hours". On the 16th of this month (and many other days) they both happen in one day within 16 hrs of each other. See the chart below. I believe your 24 3/4 hour figure is the time it takes the earth to rotate to the point where the moon is again aligned with the earth. Since the moon traveled through it's orbit while the earth was rotating, the "extra" 3/4 hour is needed to "catch up" to where the moon moved to. This would explain the tidal time "ADVANCE" on a daily basis. U.S. Naval Observatory Astronomical Applications Department Sun and Moon Data for One Day The following information is provided for Piermont, Rockland County, New York (longitude W73.9, latitude N41.0): Wednesday 16 June 2004 Eastern Daylight Time SUN Begin civil twilight 4:49 a.m. Sunrise 5:23 a.m. Sun transit 12:56 p.m. Sunset 8:30 p.m. End civil twilight 9:04 p.m. MOON Moonset 6:53 p.m. on preceding day Moonrise 4:12 a.m. Moon transit 11:59 a.m. Moonset 7:54 p.m. Moonrise 4:50 a.m. on following day I think they meant about 24 3/4 hours between moonrises OR moonsets, not between a moonrise AND a moonset. (ie 4:12 am to 4:50 am the following day) Edited June 7, 2004 by Stunod Quote
Neo_Geo Posted June 7, 2004 Posted June 7, 2004 (edited) I think they meant about 24 3/4 hours between moonrises OR moonsets, not between a moonrise AND a moonset. (ie 4:12 am to 4:50 am the following day) That's exactly what I meant - thank you. I was a little rushed when replying. And to further clarify, it all depends on what lattitude and what day of the year. Your mileage may vary! In my case, Washington, DC today, it's roughly 24 and 3/4 hours from moonrise Saturday night to moonrise Monday morning. Farther North, it might be closer to 25 hours. In Barrow, Alaska, the sun and moon ain't rising or setting at all - they're just circling around above the horizon. Actually, I'm not sure about the moon - I think it's probably circling around below the horizon this time of year. Edited June 7, 2004 by Neo_Geo Quote
+wxboss Posted June 7, 2004 Posted June 7, 2004 Hello all i noticed to day on my garmin gpsmap 60c that on my sun and moon page that i have the proper date and time and my location enabled i have the sunrise time and sunset time and and moonset time but no moonrise time what gives thanks The first time I bought a GPS and looked at the moon/sun page, I saw the same thing, and my thoughts were the same as yours. It didn't occur to me that this was the case until I started the 'looping' feature and realized what was going on. My initial thoughts were a defective unit also . Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.