Summer Solstice

The summer solstice will occur at 05:54HST today.

Sunset among the puʻu of Mauna Kea
Sunset light and fog in among the puʻu on the south flank of Mauna Kea

The Sun has reached the most northerly declination it will achieve this year. After today the Sun begins to move south in our skies.

Today will be the longest day of the year for those of us located in the northern hemisphere.

Today is considered the start of summer for most cultures in the northern hemisphere, or the start of winter 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

Waimea Lāhainā Noon Reminder

Today at 12:19HST will be Lāhainā Noon in Waimea on the Big Island, the moment when shadows disappear.

The exact date and time varies significantly across the islands and from year to year. The table below shows the time of Lāhainā Noon for various cities in 2019.

Lahiana Noon for May 2019
CityLong.Lat.DateTimeElevation
Naalehu 155°35’W19°03’NMay1512:19HST89.9
Hilo 155°05’W19°42’NMay1812:17HST89.9
Kona 155°59’W19°39’NMay1812:20HST89.9
Waimea 155°40’W20°01’NMay2012:19HST89.9
Hawi 155°50’W20°14’NMay2112:20HST90.0
Hana 156°00’W20°46’NMay2312:21HST89.9
Kihei 156°27’W20°45’NMay2312:23HST89.9
Kahalui 156°28’W20°53’NMay2412:23HST89.9
Lahaina 156°40’W20°53’NMay2412:23HST89.9
Lanai City156°55’W20°50’NMay2412:24HST89.9
Kaunakakai157°01’W21°05’NMay2512:25HST89.9
Honolulu 157°49’W21°18’NMay2612:28HST89.9
Kaneohe 157°48’W21°25’NMay2712:28HST89.9
Waialua 158°08’W21°34’NMay2812:30HST89.9
Lihue 159°22’W21°58’NMay3112:35HST90.0
Data from US Naval Observatory Data Services

Hilo & Kona Lāhainā Noon Reminder

Today will be Lāhainā Noon in Hilo and Kailua-Kona, the moment when shadows disappear.

The event will occur at 12:17HST in Hilo, and three minutes later further west in Kailua-Kona at 12:20HST.

The exact date and time varies significantly across the islands and from year to year. The table below shows the time of Lāhainā Noon for various cities in 2019.

Lahiana Noon for May 2019
CityLong.Lat.DateTimeElevation
Naalehu 155°35’W19°03’NMay1512:19HST89.9
Hilo 155°05’W19°42’NMay1812:17HST89.9
Kona 155°59’W19°39’NMay1812:20HST89.9
Waimea 155°40’W20°01’NMay2012:19HST89.9
Hawi 155°50’W20°14’NMay2112:20HST90.0
Hana 156°00’W20°46’NMay2312:21HST89.9
Kihei 156°27’W20°45’NMay2312:23HST89.9
Kahalui 156°28’W20°53’NMay2412:23HST89.9
Lahaina 156°40’W20°53’NMay2412:23HST89.9
Lanai City156°55’W20°50’NMay2412:24HST89.9
Kaunakakai157°01’W21°05’NMay2512:25HST89.9
Honolulu 157°49’W21°18’NMay2612:28HST89.9
Kaneohe 157°48’W21°25’NMay2712:28HST89.9
Waialua 158°08’W21°34’NMay2812:30HST89.9
Lihue 159°22’W21°58’NMay3112:35HST90.0
Data from US Naval Observatory Data Services

Lāhainā Noon

Lāhainā Noon is that moment when the Sun is directly overhead. At the moment of Lāhainā Noon shadows disappear.

As the islands lie south of the Tropic of Cancer there is a day when the Sun will pass directly overhead as the summer solstice approaches, generally in late May. There is a second noon as the Sun’s position moves south again in July.

The term Lāhainā Noon is unique to the islands, being adopted by the Bishop Museum in the 1990’s to describe this event. The Hawaiian term lā hainā translates roughly as cruel Sun.

The exact date and time varies significantly across the islands and from year to year. The table below shows the time of Lāhainā Noon for various cities in 2019.

Lahiana Noon for May 2019
CityLong.Lat.DateTimeElevation
Naalehu 155°35’W19°03’NMay1512:19HST89.9
Hilo 155°05’W19°42’NMay1812:17HST89.9
Kona 155°59’W19°39’NMay1812:20HST89.9
Waimea 155°40’W20°01’NMay2012:19HST89.9
Hawi 155°50’W20°14’NMay2112:20HST90.0
Hana 156°00’W20°46’NMay2312:21HST89.9
Kihei 156°27’W20°45’NMay2312:23HST89.9
Kahalui 156°28’W20°53’NMay2412:23HST89.9
Lahaina 156°40’W20°53’NMay2412:23HST89.9
Lanai City156°55’W20°50’NMay2412:24HST89.9
Kaunakakai157°01’W21°05’NMay2512:25HST89.9
Honolulu 157°49’W21°18’NMay2612:28HST89.9
Kaneohe 157°48’W21°25’NMay2712:28HST89.9
Waialua 158°08’W21°34’NMay2812:30HST89.9
Lihue 159°22’W21°58’NMay3112:35HST90.0
Data from US Naval Observatory Data Services

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

Perihelion

Earth’s perihelion will occur at 19:20HST today.

Sunrise over Georgia Strait
Sunrise over Georgia Strait

Perihelion occurs when the Earth reaches its closest distance to the Sun for the year.

It may seem odd to some the perihelion occurs in the middle of winter. One must recall that the distance from the Sun is not the cause of our seasons, that is the effects of axial tilt.

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

Winter Solstice

Winter solstice occurs today at 16:28HST. Today the Sun will occupy the most southerly position in the sky of the year. The term solstice comes from the Latin terms Sol (the Sun) and sistere (to stand still). On this day the Sun seems to stand still as it stops moving southwards each day and begins move to the north. This is the first day of winter as marked by many cultures in the northern hemisphere. Alternately, this is the first day of summer for those folks in the southern hemisphere.

2017 Solstices and Equinoxes
  UT HST
Perihelion Jan 4 14:18UT Jan 4 04:18HST
Vernal Equinox Mar 20 10:29UT Mar 20 00:29HST
Summer Solstice Jun 21 04:24UT Jun 20 18:24HST
Apehelion Jul 3 20:11UT Jul 3 10:11HST
Autumnal Equinox Sep 22 20:02UT Sep 22 10:02HST
Winter Solstice Dec 21 16:28UT Dec 21 06:28HST
Source: USNO data Services

 

Autumnal Equinox

Fall equinox occurs today at 10:02HST. Today there will be little difference between the length of the night compared to number of daylight hours. This is the first day of fall as marked by many cultures in the northern hemisphere.

2017 Solstices and Equinoxes
  UT HST
Perihelion Jan 4 14:18UT Jan 4 04:18HST
Vernal Equinox Mar 20 10:29UT Mar 20 00:29HST
Summer Solstice Jun 21 04:24UT Jun 20 18:24HST
Apehelion Jul 3 20:11UT Jul 3 10:11HST
Autumnal Equinox Sep 22 20:02UT Sep 22 10:02HST
Winter Solstice Dec 21 16:28UT Dec 21 06:28HST
Source: USNO data Services

 

Apehelion

Today the Earth is furthest from the Sun, a point called apehelion. We will be about 152,096,000km (94,508,000miles) from the Sun. Compare this to the 147,099,000km (91,403,000miles) we were at perihelion on January 4th, a difference of about 4,996,000km (3,104,000miles) occurring throughout one orbit.

It may seem odd that we are actually at the furthest for the middle of northern summer, you just have to remember that proximity to the Sun is not the cause of the seasons. The seasons are caused by the axial tilt of the Earth, creating short and long days throughout the year, with a resulting change in the angle and intensity of the sunlight.

2017 Solstices and Equinoxes
  UT HST
Perihelion Jan 4 14:18UT Jan 4 04:18HST
Vernal Equinox Mar 20 10:29UT Mar 20 00:29HST
Summer Solstice Jun 21 04:24UT Jun 20 18:24HST
Apehelion Jul 3 20:11UT Jul 3 10:11HST
Autumnal Equinox Sep 22 20:02UT Sep 22 10:02HST
Winter Solstice Dec 21 16:28UT Dec 21 06:28HST
Source: USNO data Services

 

Summer Solstice

Summer solstice occurs today at 18:24HST. Today the Sun will occupy the most northerly position in the sky of the year. The term solstice comes from the latin terms Sol (the Sun) and sistere (to stand still). On this day the Sun seems to stand still as it stops moving northwards each day and begins move to the south. This is the first day of summer as marked by many cultures in the northern hemisphere. Alternately this is the first day of winter for those living south of the equator.

This year many calendars will mark September 21st as the summer solstice, and so it is for much of the world. Here in Hawaiʻi the solstice actually occurs on the 20th when considering the time zone differences.

2017 Solstices and Equinoxes
  UT HST
Perihelion Jan 4 14:18UT Jan 4 04:18HST
Vernal Equinox Mar 20 10:29UT Mar 20 00:29HST
Summer Solstice Jun 21 04:24UT Jun 20 18:24HST
Apehelion Jul 3 20:11UT Jul 3 10:11HST
Autumnal Equinox Sep 22 20:02UT Sep 22 10:02HST
Winter Solstice Dec 21 16:28UT Dec 21 06:28HST
Source: USNO data Services