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[Centaur]

Who will be the first to spot the August New Moon with naked eyes after sunset? The Dark Moon will be in geocentric longitudinal conjunction with the Sun on 2010 AUG 10 at 03:08 UT (09 at 22:08 CDT).

We’re well past the summer solstice when we entered the half-year period that is relatively poor for sighting really young Moons from north of the tropics. This month’s waxing crescent Moon’s latitude well south of the ecliptic increases the negative effect of the ecliptic’s sharp intersection with the dusk horizon at this time of year. North Americans will likely find it impossible to find the one-day-old Moon on August 10 or even the two-day-old Moon on August 11. Even Diana’s Bow (three-day-old Moon) may be rather hard to spot on August 12. When the Moon’s apparent disk becomes more than 20% illuminated on August 13 most observers finally should have some success. It will be interesting to see who accepts and succeeds with the tough challenge this month.

I’ve created three graphics previewing the western sky after sunset on August 11, 12 &13. They all should well serve most North American observers. They can be seen by clicking: www.curtrenz.com/astronomical then going to the Moon page.

Photos and descriptions of the August New Moon would be welcome additions to this thread. Please include the date, time, time zone and location. Good Luck!

Below is a photo I took from Arlington Heights, Illinois after sunset on 2007 SEP 13 of a 2.5-day-old Moon under circumstances similarly difficult to this month.

[Paulie pchris00]

I always accept the challenge, Curt! My biggest obstacle so far this year has been clouds.

[Paulie pchris00]

After checking out your graphics, I think the 12th looks achievable, and the 13th looks really cool, like a diamond of planets and the Moon. That will be interesting to see, though it's been hard to spot Mars and Saturn naked eye lately.

I didn't realize how far below the ecliptic the Moon has been, although I kind of noticed it when it was near Jupiter last week. They rose more side by side than the diagonal along the ec liptic that I expected.

[Paulie pchris00]

I did catch the two day old last month.

astronomer.proboards.com/index.cgi?board=Lunar&action=display&thread=2778

pchris00pnc.blogspot.com/2010/07/movie-under-stars-in-valparaiso.html

[Centaur]

Aug 9, 2010 12:37:20 GMT -6 Paulie pchris00 said:

I didn't realize how far below the ecliptic the Moon has been, although I kind of noticed it when it was near Jupiter last week. They rose more side by side than the diagonal along the ec liptic that I expected.

Thanks for accepting the challenge, Paulie. Good Luck! Yours was a fine report in July. I too watched the Moon and Jupiter rising nearly simultaneously on July 31 while they were fairly widely separated, although I did expect it. Actually, the Moon was well north of the ecliptic at the time. It crosses the ecliptic twice every 27.21 days at the nodes for the 5° intersection between the ecliptic and the Moon’s orbital plane. Those nodes precess through 360° of the ecliptic every 18.6 years. Eclipses take place near the nodes. The Moon was at the descending (heading south) node on August 7. It will achieve maximum geocentric southern ecliptical latitude of 5.2° on August 13. Then on August 20 it will be at the ascending node heading north.

The Moon’s southern ecliptical latitude is one of two problems this year for early spotting of the New Moon during the months surrounding the autumnal equinox. (As a side note, I prefer the traditional definition of the New Moon being the first crescent Moon spotted after its conjunction with the Sun, rather than the more modern concept of it only being the moment of conjunction.) The other problem, one that occurs every year for spotting young Moon’s during the months surrounding the autumnal equinox, is the sharp slant of the ecliptic against the horizon at sunset. It veers toward the south where the Sun will be heading during the following months.

The Moon stays fairly close to the ecliptic, but as noted earlier it can stray more than 5° north or south of it. This year both processes are working against us. The flip side is that we're able to observe especially young Moons during the late winter and early spring.

Check out my Moon webpage for a graphic demonstraing the 2010 positional variations in all twelve Diana's Bows (three-day-old Moons about 10% illuminated).

[Paulie pchris00]

I'm not great at working out where the ecliptic is unless I have three or more planetary bodies close together, and then I just guess that it's the median. It's something I will try to pay better attention to.

[Paulie pchris00]

Hillary and I spotted it last night, with Venus, Mars, and Saturn. I don't have time to post the entire story and pictures at the moment, but I will do so as soon as I can.

Here is a picture of the Moon Wednesday night as it went behind the treeline, taken with my camera held to a 25mm eyepiece on my 6" Dob.

Attachments:

[Paulie pchris00]

The picture above isn't the one I wanted. This is the Moon sinking behind the tree.

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[Chicago Astronomer - Astro Joe]

Excellent captures Paulie.

I missed these past two days of crescents.

A polarizer filter would help in bringing out the contrast.

[Paulie pchris00]

Sorry, I wanted to repost the story here, but I'm WAY short on time, so I'm being lazy and posting the link to my blog instead.

pchris00pnc.blogspot.com/2010/08/august-2010-new-moon-spotting.html