Spring arrives tomorrow! West Seattle equinox-sunset event

(March 2011 WSB photo)
It happens four times a year and it wouldn’t be the same without NASA Solar System Ambassador Alice Enevoldsen … an equinox/solstice sunset watch. The spring equinox is late tomorrow night, so Alice is inviting everyone to watch tomorrow’s sunset at Solstice Park (uphill from the tennis courts at Fauntleroy/Webster; here’s a map):

It’s time for the 12th seasonal sunset watch (We’re at 3 years of these, folks)!!

When: March 19, 2011 at 7:05 pm (so come at 6:45 pm)

Actual sunset is supposed to be at 7:22, but at the summer solstice we noticed that the Sun set about 10 minutes earlier than the USNO says it does, so I’ve moved the time of our sunset watch up so we don’t miss it. I added another 5 minutes for the tall trees of Lincoln Park blocking our view. In Autumn the timing seemed to line up correctly – what will it do this time?

Where: Solstice Park – all the way up the hill from the tennis courts (or, if you’re not in Seattle, wherever you have a view of the western horizon!)

Who: Everyone welcome, as usual.

Come watch the spring equinox sunset at Solstice Park in West Seattle on Monday the 19th. We’ll see if the sunset lines up with the placed marker (it did for summer, but we weren’t sure in autumn or winter). I’ll be there even if it is cloudy because sometimes the Sun peeks through just as it begins to set, but if it is driving rain or sleet I’m staying home with some hot tea!

If you’re interested – here’s the timing of various celestial events from Seattle, courtesy of the U.S. Naval Observatory Astronomical Applications Department:

Sun and Moon Data for One Day

The following information is provided for Seattle, King County, Washington (longitude W122.3, latitude N47.6):

Monday 19 March 2012 Pacific Daylight Time

SUN
Begin civil twilight 6:42 a.m.
Sunrise 7:13 a.m.
Sun transit 1:17 p.m.
Sunset 7:22 p.m.
End civil twilight 7:52 p.m.

MOON
Moonset 3:40 p.m. on preceding day
Moonrise 5:38 a.m.
Moon transit 11:08 a.m.
Moonset 4:47 p.m.
Moonrise 6:02 a.m. on following day

Phase of the Moon on 19 March: waning crescent with 8% of the Moon’s visible disk illuminated.

New Moon on 22 March 2012 at 7:38 a.m. Pacific Daylight Time.

This event is my part of the NASA’s Solar System Ambassador program, and thanks to West Seattle Blog for publicizing the last few!

Everyone is welcome, see you there!
~Alice!

1 Reply to "Spring arrives tomorrow! West Seattle equinox-sunset event"

  • BlairJ March 19, 2012 (11:41 am)

    “…at the summer solstice we noticed that the Sun set about 10 minutes earlier than the USNO says it does…” The USNO sunset time is calculated for a smooth globe, without mountains or valleys. So the time that the sun goes down behind the mountains is a few minutes earlier than the time it would set below the theoretical “horizon” of a smooth globe (and the opposite for sunrise).

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