Solstice and Equinox

Always view the Sun safely!
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Christopher K.
Posts: 4333
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Solstice and Equinox

Post by Christopher K. » June 28th, 2013, 11:17 am

The solstice is a date (there are two) during which the Earth's axis is most tilted either toward or away from the Sun. During an equinox, the center of the Sun's disk crosses the equator. The actual day during which there is equal daylight and nighttime is actually a few days before and after the equinoxes.

Last Friday's APOD shows the Sun setting in Italy during last year's summer solstice.

More information:
"Sunrise and Sunset Times Near the Solstices": http://aa.usno.navy.mil/faq/docs/rs_solstices.php

Last Friday's APOD:
http://apod.nasa.gov/apod/ap130621.html

Christopher K.
Posts: 4333
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Solstice and Equinox

Post by Christopher K. » June 21st, 2014, 12:26 pm

It officially became summer at 5:51am CDT. This weekend is the halfway point of tough viewing times during which it is faint twilight for a majority of HRPO public hours.

NOAA has a brief but entertaining essay describing when summer begins as opposed to when we start to "feel" summer in the climate...
http://www.ncdc.noaa.gov/news/meteorolo ... cal-summer

Christopher K.
Posts: 4333
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Solstice and Equinox

Post by Christopher K. » December 2nd, 2015, 6:28 pm

The winter solstice this year is on the 21st. However, tonight (for Baton Rouge's latitude) saw the earliest sunset of the year! There might still be a last glimpse of reddish-orange in the southwest. Sadly, clouds are numerous.

Christopher K.
Posts: 4333
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Solstice and Equinox

Post by Christopher K. » December 23rd, 2015, 2:11 pm

Well, the winter solstice passed with not much indication of chilliness. In fact, between now and Monday night it is forecast to be no lower than nine degrees Centigrade.

Christopher K.
Posts: 4333
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Solstice and Equinox

Post by Christopher K. » March 18th, 2016, 3:43 pm

Vernal equinox is tomorrow at 11:30pm CDT--and the night after is forecast to be a degree or two above freezing! Yet it's also forecast to be clear, so take advantage and stay out as long as possible to view the heavens.

Christopher K.
Posts: 4333
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Solstice and Equinox

Post by Christopher K. » March 28th, 2016, 2:24 pm

I know we sometimes complain that the Sun seems to target south Louisiana like nobody's business, but how about not seeing the Sun for several months? Jesse Milton of NOAA calls the South Pole Station "the coldest, driest, flattest place you can imagine". Personnel there have just had their first week of not seeing the Sun for six months!

More information:
http://www.noaa.gov/last-light-sunset-south-pole

Christopher K.
Posts: 4333
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Solstice and Equinox

Post by Christopher K. » June 21st, 2016, 1:48 am

The first full day of summer! The solstice was yesterday at 5:34pm CDT.

For HRPO this means complete immersion in Stargazers Camp and ARRL Field Day right around the corner. For BRAS this means complete immersion in outreaches for the EBRPL Library.

Christopher K.
Posts: 4333
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Solstice and Equinox

Post by Christopher K. » March 19th, 2017, 8:03 pm

The spring equinox will occur at 5:29am CDT tomorrow (fall begins, of course, in the Southern Hemisphere). The spring season certainly heralds the start of many of the special events to celebrate the Highland Road Park Observatory's twentieth anniversary. NanoDays is on the 25th, followed by Tabetha Boyajian's presentation on Tabby's Star on 10 April, Brad Schaefer's annual Star of Bethlehem talk on Good Friday, and International Astronomy Day on 29 April.

Christopher K.
Posts: 4333
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Solstice and Equinox

Post by Christopher K. » May 24th, 2017, 10:58 am

The Sun sets at its latest at the beginning of summer. The ability for HRPO to bring dark sky viewing to the public at that time is exacerbated further by "Daylight Time". Therefore, starting this year there will be no Evening Sky Viewing on the Saturday and Friday flanking the first day of summer. So for 2017, HRPO will have no Evening Sky Viewing on Saturday 17 June and Saturday 23 June. Administrative hours for both days will be 12pm the 6pm.

Christopher K.
Posts: 4333
Joined: October 12th, 2009, 3:28 pm
Location: Baton Rouge, LA

Re: Solstice and Equinox

Post by Christopher K. » September 22nd, 2018, 6:37 pm

Tonight at 8:54pm CDT is the autumnal equinox. Technically, if the seasons are divided evenly throughout the Earth year, that would give each one 91.3 days of existence. The truth is probably a little more complex.

More information:
http://www.daviddarling.info/encycloped ... asons.html

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