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Astro Bob: 52 minutes of extra sunshine and counting

If you've noticed the evenings getting brighter you're not imagining things.

Sunrise sun pillar sundog subsun Feb 2_2018 BS.jpg
Minute by the minute, the sun rises earlier and sets later this month. Have you noticed the difference in the amount of daylight yet? It's most pronounced in the evening. (Bob King)

Monday, I finished skiing a local trail when the last peach-colored rays of sunlight lit up the bare treetops. I looked at my phone. Wait a minute — 5 o'clock? That's more than a half-hour earlier than the sun set on December 21st, the first day of winter. Checking the tables, I discovered that as of Jan. 26 my corner of the world has gained 40 minutes of evening and 12 minutes of morning daylight for a grand total of 52 radiant minutes.

Tomorrow, that number ticks up to 55. Our headlong rush into daylight almost makes me giddy. Besides extending the time available for outdoor activities and making driving less of a chore, the steady erosion of night goes deeper. It's a story with a circular narrative, one that ends as it began with the characters transformed in the process.

Sun high low solstice winter summer Anno.jpg
The sun's changing elevation, which increases daylight length from the winter to the summer solstice, is a reflection of Earth's tipped axis. If instead of 23.5° the axis were tipped 0°, the sun's elevation would remain constant across the year. (Stellarium)

The slow succession of one season to the next as told by the changing elevation of the sun in the sky forms the basis of our story. In January, the sun moves steadily north, which in the northern hemisphere means upward, toward the top of the sky. The higher the sun climbs, the longer it spends in the sky, and the greater the amount of daylight we experience All this comes at a price, of course. Nights get shorter. That's no trouble now given how much time is still devoted to darkness. But it does become an issue in the summer when we have to wait late into the night to finally see the stars.

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I enjoy the rhythm of the light. The pace is slow and subtle at first but then becomes increasingly obvious. Change feels good. We sense that things are moving. Within that lies possibility. What better way to inspire hope than an extra minute or two of daylight here and there?

Jupiter and Saturn SOHO Jan 26.jpg
Jupiter and Saturn shine very close to the sun on Jan. 26 — Jupiter to the east (still in the evening sky) and Saturn to the west in the morning sky. Horizontal lines through the planets are caused by "blooming" that results when the a bright, point-like celestial object oversaturates the camera's sensor chip. Cosmic rays, which are high-speed subatomic particles shot into space by the sun and other sources, leaves short, bright trails during the exposure. (SOHO photo by ESA / NASA)

Nature is replete with rhythms. Earth spins, planets revolve, variable stars pulsate, and the moon waxes and wanes. I wrote recently about how you can continue to follow the planets in broad daylight by taking advantage of the orbiting Solar and Heliospheric Observatory (SOHO). Using a special device called a coronagraph to artificially eclipse the sun, SOHO can picture stars, planets, asteroids and comets right up to the edge of the solar disk.

SOHO LASCO C3 coronagraph Worachte Boonplod.jpg
This diagram plots the paths of celestial objects that will cross the LASCO C2 coronagraph's field of view. Each line or arc represents the path of a single object. Outer planets and stars always move from left to right across the view, while the inner planets Mercury and Venus can travel in both directions — left to right when passing between the Earth and sun and right to left when orbiting on the opposite side of the sun from the Earth. Some objects pass through the narrower field of view of the C2 coronagraph. (Worachate Boonplod)

Today we'll expand on that with a calendar-diagram displaying all sorts of fun events throughout the year. The big blue circle is the LASCO C3 coronagraph's field of view which spans 15°, wide enough to take in Mercury, Venus, Jupiter and Saturn in the same picture. The small white square is the narrower field of view of a second coronagraph on board the observatory called LASCO C3.

Each line represents the path of an object with an arrow to indicate its direction of motion. Objects labeled 323P, 342P and C/2020 S3 are comets. Below you'll find a list of upcoming events. Bookmark the SOHO images site , and when you feel like a little "daytime-gazing," click on either the blue LASCO C3 or red LASCO C2 photo for a high-resolution view.

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SOHO comet Dec 15 2011.jpg
A bright comet crosses the view of SOHO's C2 coronagraph back in December 2011. (ESA / NASA)

A number of amateur astronomers routinely monitor SOHO images to find new comets in the sun's vicinity that are otherwise invisible in daylight from the ground. More than 4,000 have been discovered this way! To participate and potentially spot a new comet, check out The Official Guide to SOHO Comet Hunting . If you regularly monitor the photos you'll also be among the first to catch sight of coronal mass ejections, massive outbursts of solar plasma launched into space that can spark spectacular auroras.

Passes through the LASCO C3 coronagraph:

Jan 15-Feb 1: Saturn magnitude +0.6, moving left to right
Jan 19-Feb 8: Jupiter mag. -1.9, left to right
Feb 4-12: Mercury mag. +5, left to right
Feb 22-Apr 25: Venus mag. -4, right to left
Mar 2-19: Neptune mag +8.9, left to right
Mar 30-Apr 15: asteroid Ceres mag +9, left to right
Apr 11-Apr 25: Mercury mag -2, right to left
Apr 22-May 9: Uranus mag +5.9, left to right
Jun 5-16: Mercury mag +5, left to right
Jul 25-Aug 9: Mercury mag -2, right to left
Sep 14-Nov 1: Mars mag +1.7, left to right
Oct 6-13: Mercury mag +5, left to right
Oct 18-20: 342P/SOHO mag +7, left to right to left
Nov 11-Dec 14: Vesta mag +7.5, left to right
Nov 15-Dec 13: Mercury mag -1, right to left

"Astro" Bob King is a freelance writer for the Duluth News Tribune. Read more of his work at duluthnewstribune.com/astrobob .

"Astro" Bob King is a freelance writer and retired photographer for the Duluth News Tribune. You can reach him at nightsky55@gmail.com.
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