Vernal Equinox

The spring equinox will occur at 19:20HST today.

Sunrise over Georgia Strait
Sunrise over Georgia Strait

The equinox is defined as the time at which the Sun passes through the plane of the Earth’s equator. Until the fall equinox occurs on Sep 22nd, the Sun will be located in the northern hemisphere with a positive declination coordinate.

Today the length of the day and night will be very near equal, thus the term equinox. the Sun will rise and set nearly exactly due east and due west.

Today is considered the start of spring for most cultures in the northern hemisphere, or the start of fall for those in the southern hemisphere.

2019 Apsides and Seasons
Event Universal TimeHawaii Standard Time
Perihelion Jan 0305:20UTJan 0219:20HST
Spring Equinox Mar 2021:58UTMar 2011:58HST
Summer SolsticeJun 2115:54UTJun 2105:54HST
Aphelion Jul 0422:11UTJul 0412:11HST
Fall Equinox Sep 2307:50UTSep 2221:50HST
Winter SolsticeDec 2204:19UTDec 2118:19HST
Data from US Naval Observatory Data Services

Mercury at Inferior Conjunction

Today Mercury is passing through inferior conjunction, passing between the Sun and the Earth. This fast moving planet will reappear above the dawn in about a week, rising towards maximum elongation on April 11th.

This is the most favorable dawn apparition of the year, actually the best dawn or evening, with the planet reaching over 27° away from the Sun.

Mercury Events for 2019
ApparitionDate ElongationMagnitude
Evening Feb 2718.1°E -0.2
Morning Apr 1127.7°W +0.6
Evening Jun 2325.2°E +0.7
Morning Aug 919.0°W +0.3
Evening Oct 2024.6°E +0.1
Morning Nov 2820.1°W -0.3
Data from the Mercury Chaser’s Calculator by John Walker

New Moon at Kaʻohe

It was a very nice night, clear dark skies and bright stars.

Andrew and Maureen observing at Kaʻohe
Andrew and Maureen observing at Kaʻohe

A usual the club’s dark sky star party was held this month at Kaʻohe. After two months of poor weather I was ready for a good night out with a telescope. A few others were too, and joined the club out in the dark.

Arriving at the site there was a thin cloud deck overhead. With years of experience here I looked up and told Maureen that the clouds would be gone in an hour. It did not even take that long, the clouds dissolved right after sunset, leaving a clear skies before we were finished setting up.

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