Tag: Sun

Earth at Perihelion

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

It may seem odd that we are actually at the closest for the middle of northern winter, 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.

2016 Solstices and Equinoxes
  UT HST
Perihelion Jan 2 22:49UT Jan 2 12:49HST
Vernal Equinox Mar 20 04:30UT Mar 19 18:30HST
Summer Solstice Jun 20 22:34UT Jun 20 12:34HST
Apehelion Jul 4 16:24UT Jul 4 06:24HST
Autumnal Equinox Sep 22 14:21UT Sep 22 04:21HST
Winter Solstice Dec 21 10:44UT Dec 21 00:44HST
 
Source: USNO data Services

 

Winter Solstice

Winter solstice occurs today at 18:48HST. 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.

2015 Solstices and Equinoxes
  UT HST
Perihelion Jan 4 08:59UT Jan 3 22:59HST
Vernal Equinox Mar 20 22:45UT Mar 20 12:45HST
Summer Solstice Jun 21 16:38UT Jun 21 06:38HST
Apehelion Jul 6 12:59UT Jul 6 02:59HST
Autumnal Equinox Sep 23 08:20UT Sep 22 22:20HST
Winter Solstice Dec 22 04:48UT Dec 21 18:48HST
 
Source: NASA Sky Calendar

 

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 3rd, 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.

2014 Solstices and Equinoxes
  UT HST
Perihelion Jan 4 05:59UT Jan 3 19:59HST
Vernal Equinox Mar 20 16:57UT Mar 20 06:57HST
Summer Solstice Jun 21 10:52UT Jun 21 00:52HST
Apehelion Jul 6 02:59UT Jul 5 16:59HST
Autumnal Equinox Sep 23 02:30UT Sep 22 16:30HST
Winter Solstice Dec 21 23:03UT Dec 21 13:03HST
 
Source: NASA Sky Calendar

 

Earth at Perihelion

Today the Earth is closest to the Sun, a point called perihelion. We will be about 147,099,000km (91,403,000miles) from the Sun. Compare this to the 152,096,000km (94,508,000miles) we will be at aphelion on July 6th, a difference of about 4,996,000km (3,104,000miles) occurs throughout one orbit.

It may seem odd that we are actually at the closest for the middle of northern winter, 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.

2015 Solstices and Equinoxes
  UT HST
Perihelion Jan 4 08:59UT Jan 3 22:59HST
Vernal Equinox Mar 20 22:45UT Mar 20 12:45HST
Summer Solstice Jun 21 16:38UT Jun 21 06:38HST
Apehelion Jul 6 12:59UT Jul 6 02:59HST
Autumnal Equinox Sep 23 08:20UT Sep 22 22:20HST
Winter Solstice Dec 22 04:48UT Dec 21 18:48HST
 
Source: NASA Sky Calendar

 

Winter Solstice

Winter solstice occurs today at 13:03HST. 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.

2014 Solstices and Equinoxes
  UT HST
Perihelion Jan 4 05:59UT Jan 3 19:59HST
Vernal Equinox Mar 20 16:57UT Mar 20 06:57HST
Summer Solstice Jun 21 10:52UT Jun 21 00:52HST
Apehelion Jul 3 22:59UT Jul 3 12:59HST
Autumnal Equinox Sep 23 02:30UT Sep 22 16:30HST
Winter Solstice Dec 21 23:03UT Dec 21 13:03HST
 
Source: NASA Sky Calendar

 

An Enormous Sunspot Complex

Sunspot complex AR2192 is the largest I have seen in a long time. Easily visible without a telescope, simply using appropriate eye protection. It is quite large, more than ten times the diameter of the Earth. There are reports of it being noticed at sunset.

I photographed the sunspot during lunch fron Waimea, setting up a little telescope next to my vehicle in the Keck parking lot. The photo was taken using a TV-76mm telescope, the EOS-M camera and a Baader solar film filter, the same setup I viewed the Venus transit with.

Of course there was a partial solar eclipse today, visible across western North America. Photos of this enormous sunspot and the eclipse are now being posted across the web. Unfortunately this eclipse was not visible from Hawai’i. If you have not taken a look, I urge you to step outside with your solar viewing glasses and take a quick look. You do have solar viewing glasses handy… Right?

Sunspot AR2192
Sunspot complex AR2192 on 23 October, 2014, Canon EOS-M and TV-76mm telescope

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 be at perihelion on January 3rd, 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.

2014 Solstices and Equinoxes
  UT HST
Perihelion Jan 4 05:59UT Jan 3 19:59HST
Vernal Equinox Mar 20 16:57UT Mar 20 06:57HST
Summer Solstice Jun 21 10:52UT Jun 21 00:52HST
Apehelion Jul 3 22:59UT Jul 3 12:59HST
Autumnal Equinox Sep 23 02:30UT Sep 22 16:30HST
Winter Solstice Dec 21 23:03UT Dec 21 13:03HST
 
Source: NASA Sky Calendar