Celebrating a (Solar) New Year

On January 1st, much of the world will be celebrating the new year, but this Friday might be a more appropriate day to celebrate (at least from an astronomical viewpoint).

This Friday (22 December 2018) marks the Winter Solstice, the date on which the calendar changes seasons from Fall to Winter here in Mid-Michigan (and the rest of the Northern Hemisphere).  Winter will officially begin at 5:23 PM EST.

The word solstice comes from two Latin root words sol (sun) and sistere (to stand still).  On the solstice, the path of the sun appears to stand still! 

Assume that you were to awaken every morning before dawn and mark the location that the sun rises on the eastern horizon.  You would notice that the sun does not in fact arise from the same place every day.  Instead it wanders north and south along the horizon, moving north during the Winter and Spring and back south again during the Summer and Fall.  On the Summer Solstice (June 21st) and Winter Solstice (December 21st), the sun ceases to move further along the horizon, appearing to "stand still" before reversing its course the next day.

You have probably already noticed in addition to the location of the rising sun, the length of day and night vary throughout the year.  As the sun progresses south, the day shortens and the night lengthens.  The Winter Solstice marks the shortest day (and longest night) of the year in the Northern Hemisphere.  Here in Mid-Michigan we will mark the date with approximately 8 hours 57 minutes of daylight.  As the sunrise moves back north along the horizon our days will slowly get longer until on the Summer Solstice we will experience nearly 15 hours 25 minutes of daylight.

Why does the sun move and the length of day vary?

It all has to do with a tilt in the Earth's axis.  The Earth rotates on its axis approximately once every 24 hours - giving us the length of our day.  It also revolves around the sun approximately once every 365 days - the length of our year.  If the Earth's axis was perpendicular the plane on which it revolves around the sun, our days would be the same length throughout the year (approximately 12 hours), but the axis is not perpendicular to this plane.  Instead the Earth's axis tilts 23.5 degrees from the vertical.

The points on the globe that the axis revolves around are referred to as the North and South Poles.  The axis is always pointed toward the same location in the sky.  The North Pole points toward the "North Star" - Polaris.  As the earth revolves around the sun, sometimes the North Pole is closer to the sun, sometimes the South Pole is closer to the sun.  When the North Pole is at its closest, we experience Summer in Mid-Michigan and the Southern Hemisphere experiences Winter.  When the North Pole is at its furthest, we experience Winter and the Southern Hemisphere experiences Summer.

On two days of the year, the Earth's axis is perpendicular to the plane of its revolution.  On those two days we do experience equal periods of day and night because the sun rises due east and sets due west.  During the rest of the year our hours of daylight vary depending on where the axis is pointed.  During our summer months, the tilt in the axis means that the northern hemisphere is closer to the sun and receives more hours of sunlight.  During the winter months, the reverse is true.  On the Winter Solstice, the North Pole is tilted at its furthest angle from the sun resulting in the shortest day (and longest night) of the year for those of us in the Northern Hemisphere.

Why did I say that the Winter Solstice would be a better day to celebrate the new year?

Tracking the position of the rising sun was among the first astronomical observations.  Many ancient monuments seem to have been constructed as solar observatories, aligned with the locations of sunrise and sunset on the longest and shortest day of the year.  To early agricultural societies especially, tracking the seasons accurately could mean the difference between a bountiful harvest and failure of a year's crops.  The day that the sun "stood still" in its southward journey and then began to return north, bringing more hours of daylight and eventually warmer weather seems such an obvious point to mark the beginning of a new year!

Join me on a hike to celebrate the Solstice!

To celebrate the Winter Solstice, I am leading a nighttime hike at the Chippewa Watershed Conservancy's Sylvan Solace Preserve.  This hike will begin at 7:00PM.  Sylvan Solace Preserve is located on Pickard Road, between Gilmore Road and Littlefield Road, approximately 8 miles west of downtown Mt. Pleasant.

We are doing a nighttime hike because another celestial event lines up with the solstice this year - a full moon.  (Technically the full moon will be on December 22nd, but it will be more than 97% illuminated on the night of the 21st.)  We are expecting light snowfall early in the day - this should brighten up the woods.  Hopefully the moon will peek through the expected clouds and illuminate our hike.  The trails at Sylvan Solace are flat and well-defined making this a great first night hiking experience!  I hope to do the hike without any artificial lights.  Wear warm clothes and bring a headlamp or flashlight just to be safe.

The Days of Summer - Day Eighty through Day Eighty-six

Summer is nearly at an end.  This is my next-to-last installment of my Days of Summer photography project.  I began this project on the Summer Solstice (21 June 2018) with the idea that I would photograph something in nature every day until the Fall Equinox (22 September 2018) and share one image from each day of the summer.  If you've missed the previous seventy-nine photographs, you can start to get caught with the images that I shared last week.

Day 80 (08 September) - Golden

This image of the sun shining through a Boxelder (Acer negundo) was photographed at Forest Hill Nature Area.  This is one of my favorite photos of the summer.  In addition to the sun, I like the contrast of the light sky with the band of dark trees on the horizon, the goldenrods lit up by the setting sun and the shadows in the foreground.


Day 81 (09 September) - Eastern Hemlock

We spend so much time looking down, sometimes we need to remember to look up.  This photograph was taken during a hike at the Chippewa Watershed Conservancy's (CWC) Audubon Woods Preserve.  Audubon Woods is my favorite CWC nature preserve.  On September 9th, I led a group on an off-trail hike at the preserve.  One of the sites that I led the group to was this small grove of Eastern Hemlock (Tsuga canadensis) trees.  Most visitors to the preserves never leave the established trails and I wanted to show off some of my favorite sites in the woods including this grove.


Day 82 (10 September) - Milkweed Portrait

When I started this project I knew that it would be a challenge to take a good nature photo every day, especially once school started.  Fortunately there are many local parks and preserves that can be easily accessed within a few minutes distance from schools or the office.  On September 10th, I did my first school programs of the 2018-19 School Year.  This photo was taken in the field behind the Conservation District offices after completing my classroom presentations for the day.


Day 83 (11 September) - Ah-choo!

This picture was taken at Chipp-A-Waters Park in Mt. Pleasant.  This bumble bee (and a bunch of other insects) were eating pollen and nectar from Sneezeweed (Helenium autumnale) blossoms.  I took several pictures of this bee as it foraged, but this was my favorite.  I like how you can see the bee's long tongue as it sips nectar.  I have never found Sneezeweed growing wild in Mt. Pleasant.  These flowers were planted about a decade ago as part of restoration project.


Day 84 (12 September) - Fall Abstract

I photographed these poplar leaves at the Conservation District offices.  This trees has been changing color and dropping leaves for about a week.  I thought about cropping the right leaf out of the picture to make the picture more of an abstract image, but decided that I liked the contrast of color.


Day 85 (13 September) - Coral Mushrooms

Recent rains have caused fungi to fruit in every local woods.  This image of coral mushrooms was taken at the CWC's Sylvan Solace Preserve.  I think this is one of several species of Ramaria fungi - there are several yellow Ramaria species that can be difficult to tell apart.  I would have liked to have taken several more images of this mushroom, but the rains have also caused mosquito populations to explode!  I couldn't stop in one place for more than a few seconds.  I am generally pretty tolerant of mosquitos, but they are absolutely miserable right now.


Day 86 (14 September) - Bean Fields

The final image for the week was taken in southern Isabella County.  Mid-Michigan is farm country and soy beans are one of the major crops.  I really liked the color of the sky when I took this picture and wanted to find the simplest landscape that I could.  The row of trees blocked out more distant elements and let me focus on the field and sky without worrying about other distractions.  The color of the ripening bean fields, sky, and clouds remind me of an impressionist landscape painting.

I hope that you have been enjoying viewing this series of photographs as much as I have enjoyed capturing them.  I am into the final week of the project and I don't know what my next photographic journey will be.

The Days of Summer - Day Thirty-one through Day Thirty-seven

This is installment five of my Days of Summer photography project.  (Click here to view the photos from part four.)  The intent of this project is to get outdoors everyday to photograph something in nature and to pick a single image to represent each day of the summer from the Summer Solstice (21 June 2018) to the Fall Equinox (22 September 2018).  Five weeks into summer, this has been a very rewarding project.  It takes time, but I think I am producing some of my best photography ever.  I am definitely learning more about my camera and lenses.

Enjoy.

Day 31 (21 July 2018) - Raindrops on Rosinweed

This image a raindrops on a Rosinweed (Silphium integrifolium) was photographed at home in our native pollinator garden during a lull between rain showers.

Day 32 (22 July 2018) - Monarch on Purple Coneflower

This photograph was taken at Forest Hill Nature Area during a very windy afternoon.  At one point this Monarch Butterfly (Danaus plexippus) nearly blew off the top of this Purple Coneflower (Echinacea purperea).  Despite the wind, this was a great day for pollinator photography.  I was able to photograph five butterfly species, a couple moths, numerous bees, and several wasp species.  Picking a single image for the day was difficult, but I like the position of the butterfly facing into the wind and the grass blades blowing in from the left of the picture.

Day 33 (23 July 2018) -Early Fall Colors

This picture of Red-osier Dogwood (Cornus sericea) berries and leaves was also taken at Forest Hill Nature Area.  Many of the dogwood leaves were already changing color.  This is not necessarily a sign of fall, but a sign of stress such as too little rain.

Day 34 (24 July 2018) - Green Frog

This picture was taken at Chipp-A-Waters Park in Mt. Pleasant.  I heard several Green Frogs (Lithobates clamitans) calling from a small wetland area near the back of the park.  Most of the frogs dove into the pond when I approached but this one let me approach to about five or six feet.  This image has been cropped from a horizontal to a vertical image.

Day 35 - Yeah, Here Come the Rooster

This image and the next one were actually taken indoors.  I spent much of last week at the Isabella County Fair.  County fairs are an integral part of summer across much of the United States.  This rooster was one of the many animals entered in the fair by 4H members.

If you understand the title of this image, bonus points for you!  If you don't...

Day 36 (26 July 2018) - Charolais Steer

Another image from the Isabella County Fair.  Raising beef cattle is one of the most popular projects for 4H members in the area.  It quite something to watch a nine or ten year old kid weighing maybe 100 pounds walk a full grown steer around the arena and present it for judging.  I photographed the Charolais steer  in the beef cattle barn as it stared at me from its stall.

Day 37 (27 July 2018) - Stormcloud

The final picture of the week was photographed in southern Isabella County on my way home from work.  I watched this storm approached from the west and raced to try to intersect it in a place where I could get a good image.  Don't worry, I never went above the speed limit - the gravel road that I was traveling on would not allow for speeds much above 30 mph in most sections.  I like this picture because of the contrast between the dark water laden bottom of the cloud and the sun shining through the top.

The Days of Summer - Day Seventeen through Day Twenty-three

This part three of my Days of Summer photo project.  To learn more about the inspiration for this project and to see the photos from part one and part two click on the following links:

     The Days of Summer - Day One through Day Nine
     The Days of Summer - Day Ten through Day Sixteen

 Day 17 (07 July 2018) - Snowberry Clearwing Moth

We normally think of moths as nocturnal insects, but many are adapted to daytime living.  This includes a group of sphinx moths known as Clearwings.  In North America, there are four species in the genus Hemaris.  All fly by day.  They mimic the appearance of bumblebees and the feeding behavior of hummingbirds - thus they are often known as Bumblebee Moths or Hummingbird Moths.  This one is specifically known as the Snowberry Clearwing Moth (Hemaris diffinis) after a favorite larval host plant.  This photo was taken at Forest Hill Nature Area.  This probably not the best image from the day, but I cannot resist the subject.

Day 18 (08 July 2018) - Japanese Maple

This image of Japanese Maple leaves was taken in front of our house.  I like the silhouette of the red leaves against the blue sky and the details of the delicate veins in the central leaf.

Day 19 (09 July 2018) - Impression, Michigan Lily

If the previous photo was all about details.  This one is all about impressions.  This Michigan Lily (Lilium michiganense) was photographed at Mission Creek Woodland Park.  This photo reminds me of an Impressionist painting with only the blooms pistil and one or two stamen in sharp focus.  The rest of the flower is clearly visible but much softer.  It's all about the light!

The name given to this photo was inspired by the painting that Impressionism was named after:  Impression, soleil levant (Impression, sunrise) by Claude Monet.

Day 20 (10 July 2018) - Sunlight and Basswood

The photo for Day Twenty is also all about the light.  In this image sunlight filters down through the canopy, shedding light on American Basswood (Tilia americana) leaves.  The sun itself bursts through a gap in the upper right of the image. This image was taken in Mt. Pleasant at Mill Pond Park.

Day 21 (11 July 2018) - Waves of grass

I am constantly drawn to subjects that show pattern and texture.  Choosing a photo for July 11th was difficult.  I traveled north along US 127 to North Higgins Lake State Park for a late afternoon meeting.  Before my meeting I spent a little time exploring the park and came away with images of the lake, pine trees, lichens, etc.  Most of these images focused on pattern and texture.  In the end, I selected this image because of the suggested wavelike motion of the grasses.  I could have easily selected three or four other pictures from the day,

Day 22 (12 July 2018) - Blue Vervain

This photo of Blue Vervain (Verbena hastata) was taken along the Chippewa River at Chipp-A-Waters Park in Mt. Pleasant.  The individual flowers are small, but each plant can have hundreds of blooms over the course of several weeks in mid- to late-summer.  The sheer abundance of blooms makes this an important nectar source for native bees.  Although none appear in this picture, there were dozens buzzing around this colony of plants.

Day 23 (13 July 2018) - White Water Lily with native bee

My final picture of the week shows a native bee collecting pollen from a White Water Lily (Nymphaea odorata).  I took about two dozen of pictures of this exact flower at the beginning of a walk through Mill Pond Park this morning.  I came back near the end of my walk and there was a bee on the flower.  One picture and the bee was gone...

The Days of Summer - Day One through Day Nine

I've given myself a photo project.  I love nature photography, but sometimes everything else in life gets in the way and I don't take time to get outdoors and take pictures.  So this summer I decided to do something about it.  Starting with the first day of Summer (21 June) I am going to take at least one photo every day of the season and share it here.  I wish this was an original idea, but it's not.  One of my favorite nature photographers is Jim Brandenburg.  For one season (in this case Autumn), Brandenburg took only one photo per day.  A personal project to reignite his love of photography and to connect with his home ground, these photos were not originally meant to be published but they resulted in the book called Chased By The Light: A 90-Day Journey (1998).  Five years later he published a companion book titled Looking for Summer (2003).  For Looking Brandenburg did not take one photo per day as he did for Chased, but the goal was the same to connect with a place and a time. Both Chased and Looking are sitting in our living room right now - they are among the books I turn to for photographic inspiration. 

So I'm inspired... I sit typing these words on June 29th, the ninth day of summer and I have nine photographs to share.  I am not taking a single photo a day as per Chased By The Light, but I am picking a single image to represent each day.  Collectively, I hope these photos represent the season as I experience it.  Expect updates on a weekly basis from here out.

Day One (21 June 2018) - Summer Solstice

I started summer with a sunrise hike at the Chippewa Watershed Conservancy's Bundy Hill Preserve.  While I took over 200 photos that morning, this image of a pair of brightly lit broadleaf trees in a dark pine forest is my favorite.

Day Two (22 June 2018) - Mare's Tails

I am drawn to clouds - I photograph them over and over again.  A good cloud always merits a photograph.  This image of cirrus clouds was taken on the Saginaw Chippewa Reservation just east of Mt. Pleasant on my way home from work.  I noticed the clouds and pulled into a parking lot to get this image. Cirrus clouds are often referred to as Mare's Tails because of their resemblance to the curling hairs of a horse's tail.  The word cirrus actually means "a curl of hair" in Latin.

Day Three (23 June 2018) - Baby Birds

A Boston Fern on our front porch is currently home to a nest full of baby House Finches (Haemorhous mexicanus).  When I took this picture, the nestlings were several days old but had yet to open their eyes.

Day Four (24 June 2018) - Raindrops on Butterflyweed

Sunday June 24th found us leaving for a trip to Chicago for a graduation party, and then on to Wisconsin and Iowa for a mini-vacation. I photographed this Butterflyweed (Asclepias tuberosa) in our home pollinator garden while I was packing for the truck for our trip.  It had just started to rain and the flowers were covered with hundreds of tiny water droplets. 

Day Five (25 June 2018) - Wading Whooper

One of my favorite places is the International Crane Foundation in Baraboo, Wisconsin.  We originally visited there in July 2015.  When we decided to head back to Wisconsin this summer, ICF was at the top of our list of places to visit.  During our first trip the pair of Whooping Cranes (Grus americana) stayed toward the back of their exhibit space and we barely saw them.  That almost happened again this time, but we hung around the exhibit and the birds decided it was time to feed in the pond near the viewing area.  This is not the closest image that I took, but it is my favorite of the bird in action stalking something in the pond.

Day Six (26 June 2018) -  A Row of Mounds

Our next day found us in eastern Iowa at Effigy Mounds National Monument.  I am fascinated by Native American earthworks, especially mounds.  In 2016 we visited Great Serpent Mound in Ohio and Cahokia Mounds in Illinois.  Effigy Mounds was next on my list.  These mounds are attributed to the Hopewell Culture that existed in the area approximately 1500-2000 years ago.  Although the site is best know for its effigy mounds (earthen mounds in the shapes of animals or humans) I was equally impressed by the rows of conical mounds such as this group leading up the the area known as Fire Point.


Day Seven (27 June 2018) -  Bufflehead Drake

Shara firmly believes that if a city you are visiting has an aquarium it must be visited; I tend to agree.  That's how we ended up at the National Mississippi River Museum and Aquarium in Dubuque, Iowa. My favorite thing was the American Paddlefish feeding (daily at 10:30AM), but my favorite photo was this one of a Bufflehead (Bucephala albeola) drake at the Backwater Marsh exhibit. 


Day Eight (28 June 2018) - Moonrise

The photo for June 28th was taken back home in Michigan at the Forest Hill Nature Area.  After driving home from Iowa earlier in the day, I decided to go out to Forest Hill to watch the sun set and the full moon rise.  There were not enough clouds for a spectacular sunset, but just enough to prevent really clear photos of the moon.  Even so I really like this yellow moon in the inigo sky as barely rises above the black treeline.

Day Nine (29 June 2018) - Hope is a tree with seeds

Emily Dickinson famously wrote that '"Hope" is the thing with feathers-', but to me this tree represents hope.  It's a Green Ash (Fraxinus pennsylvanica).  Why does this tree give me hope?  Do you see all the dead trees in the background?  Those are also Green Ash trees.  They were killed by the Emerald Ash Borer, an invasive species that has obliterated ash populations in Michigan and across the Midwest.  Entire forests were wiped out in a few short years.

But...

The Emerald Ash Borer didn't get every tree.  Trees that were small when the Ash Borer arrived in an area were sometimes passed over as Ash Borer populations moved on to more promising feeding grounds.  These small trees are now reaching a size where they are capable of reproducing.  In a short walk at Mill Pond Park I discovered several 15 - 25 foot Green Ash trees.  The best part of the discovery; they all had seeds (hundreds of them)!  These seeds represent hope for the survival of the species as a viable component of our forests.

Vernal Equinox 2018

An early spring sunrise (2017)

Today at 12:15 PM EST, Winter officially ends and Spring begins in the Northern Hemisphere.  The day that this change occurs is known as the Vernal (Spring) Equinox.  The word equinox comes from the Latin words aequus (equal) and nox (night).  On the Equinox the sun strikes directly on the Equator resulting in approximately equal periods of day and night across the globe.

The Earth rotates around its axis approximately once every 24 hours.  However this axis is tilted at 23.5 degrees from the vertical.  The points on the globe that the axis revolves around are referred to as the North and South Poles.  The axis is always pointed toward the same location in the sky.  The North Pole points toward the "North Star" - Polaris.

At any given time, fifty percent of the earth is in sunlight (Day) and the other fifty percent is in darkness (Night).  However, because the Earth is tilted on its axis sunlight does not always strike the Earth at the same angle.  This means during different seasons different parts of the Earth will receive varying amounts of sunlight and darkness.
  
As the earth revolves around the sun, sometimes the North Pole is closer to the sun, sometimes the South Pole is closer to the sun.  When the North Pole is at its closest, the sun lights a larger portion of the Northern Hemisphere than it does the Southern Hemisphere.  When this happens, we experience Summer in Mid-Michigan and the Southern Hemisphere experiences Winter.  When the North Pole is at its furthest from the sun, we experience Winter and the Southern Hemisphere experiences Summer.  During our Northern Winter, the sun is striking a a larger portion of the Southern Hemisphere than it is the Northern Hemisphere.  On the Equinox, the poles are essentially perpendicular to the rays of the sun so locations in the northern and southern hemispheres should receive nearly equal hours of sunlight and darkness.

Spring flowers to get you in the mood for spring - Bloodroot (Sanguinaria canadensis)

Despite what most people think, the hours of daylight and night experiences on the Equinox are not perfectly equal.  Mt. Pleasant is located at 43 degrees 36 minutes north of the equator.  On the equinox, it experiences 12 hours 9 minutes worth of daylight.  A location located at 43 degrees 36 minutes south of the equator will receive approximately the same length of daylight. There is another lesser known event that occurred over the weekend - the Vernal Equilux.  Equilux means "equal light".  On Saturday March 17th, Mid-Michigan (and many other places in the Northern Hemisphere) received approximately 12 hours of daylight and 12 hours of darkness.

The hours of daylight that Mt. Pleasant receives each day will grow until it reaches 15 hours 24 minutes around the Summer Solstice.  Then our hours of sunlight will diminish until on the Winter Solstice we experience only 8 hours 57 minutes of daylight, before increasing again. 

Winter Solstice 2017

An early winter sunrise (2013)

Winter begins tomorrow (21 December 2017) at 11:28AM.

The moment this change of seasons occurs is known as the Winter Solstice.  The word Solstice comes from the Latin words sol (sun) and sistere (to stand still).  Tomorrow the sun will have reached its lowest position in the southern Sky, giving us our shortest day of the year.  On the Summer Solstice, Mid-Michigan received approximately 15 hours and 26 minutes of sunlight.  Tomorrow Mid-Michigan will see only 8 hours and 56 minutes of sunlight, but from now until the Summer Solstice each day will grow longer.

The Earth rotates around its axis approximately once every 24 hours.  However this axis is tilted at 23.5 degrees from the vertical.  The points on the globe that the axis revolves around are referred to as the North and South Poles.  The axis is always pointed toward the same location in the sky.  The North Pole points toward the "North Star" - Polaris.

As the earth revolves around the sun, sometimes the North Pole is closer to the sun, sometimes the South Pole is closer to the sun.  When the North Pole is at its closest, we experience Summer in Mid-Michigan and the Southern Hemisphere experiences Winter.  When the North Pole is at its furthest, we experience Winter and the Southern Hemisphere experiences Summer. 

If you were to arise at dawn every day of the year and record at which point on the horizon the sun rises from you would be able to track the progression from the Summer solstice (in which the sun rises furthest North) to the Winter Solstice (in which the sun rises furthest South) and back again.  Tracking the position of the rising sun was one of the earliest astronomical observations.  Many ancient monuments were constructed to act as solar observatories, recording the longest and shortest days of the year. 

Happy Summer Solstice 2017!

Wheat ripening on the Summer Solstice

If you were to arise at dawn every day of the year and record the point on the horizon where the sun rises you would be able to track the progression from the Summer Solstice (in which the sun rises furthest North) to the Winter Solstice (in which the sun rises furthest South) and back again.  Tracking the position of the rising sun was one of the earliest astronomical observations.  Many ancient monuments were constructed to act as solar observatories, recording the longest and shortest days of the year.  These observations were used to plan planting dates for various agricultural crops.

Today the sun reached its northernmost point on the horizon.  Officially, at 12:24 AM EST Spring ended and Summer began in the Northern Hemisphere.  This moment of change is known as the Summer Solstice.  At the same time, the Southern Hemisphere was experiencing its Winter Solstice as their Fall ended and Winter began. The word Solstice comes from the Latin words sol (sun) and sistere (to stand still).  Today the sun has reached its highest position in the northern Sky, giving us our longest day of the year.  With the sunrise at 5:58 AM and sunset at 9:24 PM, mid-Michigan will experience approximately 15 hours 26 minutes of daylight today.  By comparison, Christchurch, New Zealand (which is approximately the same latitude south of the equator as Mid-Michigan is north of the equator), will have only 8 hours 56 minutes of sunlight today.
 

Field Corn (Zea mays) requires long summer days to grow and ripen

Why does the length of daylight vary?  The Earth rotates around its axis approximately once every 24 hours.  However this axis is tilted at 23.5 degrees from the vertical.  The points on the globe that the axis revolves around are referred to as the North and South Poles.  The axis is always pointed toward the same location in the sky.  The North Pole points toward the "North Star" - Polaris.

At any given time, fifty percent of the earth is in sunlight (Day) and the other fifty percent is in darkness (Night).  However, because the Earth is tilted on its axis sunlight does not always strike the Earth at the same angle.  This means that during different seasons different parts of the Earth will receive varying amounts of sunlight and darkness.
 
As the earth revolves around the sun, sometimes the North Pole is closer to the sun, sometimes the South Pole is closer to the sun.  When the North Pole is at its closest, the sun lights a larger portion of the Northern Hemisphere than it does the Southern Hemisphere.  When this happens, we experience Summer in Mid-Michigan and the Southern Hemisphere experiences Winter.  During our Northern Summer, not only does the sun light more of the Northern Hemisphere, but the sun also lights every Northern Hemisphere location for a higher percentage of the day than a comparable Southern Hemisphere location. 

When the North Pole is at its furthest from the sun, we experience Winter and the Southern Hemisphere experiences Summer.  During our Northern Winter, the sun is striking a a larger portion of the Southern Hemisphere than it is the Northern Hemisphere, and consequently the sun lights every Southern Hemisphere location for a higher percentage of the day than a comparable Northern Hemisphere location.  On two days of the year, the Spring and Fall Equinoxes, the sun lights the Northern and Southern Hemispheres equally and the length of day for will be the same for both.

Vernal Equinox 2017

The Skunk Cabbage knows that Spring has arrived.

Today at 6:28 AM EST, Winter officially ended and Spring began in the Northern Hemisphere.  The day that this change occurs is known as the Vernal (Spring) Equinox.  The word equinox comes from the Latin words aequus (equal) and nox (night).  On the Equinox the sun strikes directly on the Equator resulting in approximately equal periods of day and night across the globe.

The Earth rotates around its axis approximately once every 24 hours.  However this axis is tilted at 23.5 degrees from the vertical.  The points on the globe that the axis revolves around are referred to as the North and South Poles.  The axis is always pointed toward the same location in the sky.  The North Pole points toward the "North Star" - Polaris.

At any given time, fifty percent of the earth is in sunlight (Day) and the other fifty percent is in darkness (Night).  However, because the Earth is tilted on its axis sunlight does not always strike the Earth at the same angle.  This means during different seasons different parts of the Earth will receive varying amounts of sunlight and darkness.

 
As the earth revolves around the sun, sometimes the North Pole is closer to the sun, sometimes the South Pole is closer to the sun.  When the North Pole is at its closest, the sun lights a larger portion of the Northern Hemisphere than it does the Southern Hemisphere.  When this happens, we experience Summer in Mid-Michigan and the Southern Hemisphere experiences Winter.  When the North Pole is at its furthest from the sun, we experience Winter and the Southern Hemisphere experiences Summer.  During our Northern Winter, the sun is striking a a larger portion of the Southern Hemisphere than it is the Northern Hemisphere.

On the Equinox, the poles are essentially perpendicular to the rays of the sun so locations in the northern and southern hemispheres receive equal hours of sunlight and darkness.  Mt. Pleasant is located at 43 degrees 36 minutes north of the equator.  On the equinox, it experiences 12 hours 9 minutes worth of daylight.  A location located at 43 degrees 36 minutes south of the equator will receive approximately the same length of daylight.  The hours of daylight that Mt. Pleasant Experiences will grow until it reaches 15 hours 24 minutes around the Summer Solstice.  Then our hours of sunlight will diminish until on the Winter Solstice we experience only 8 hours 57 minutes of daylight, before increasing again.

Sunset (05 January 2017)

Last night's sunset was quite dramatic.  Shara snapped a few photos with my camera while we were driving home from work.  Here is my favorite one of the bunch.

Sunset - 05 January 2017 (photo by Shara LeValley)

To learn why we see the colors that we do at sunset (and sunrise) please check out this post on Roy G. Biv and the wavelengths of light. 

Morning in the woods

This week I am attending the Michigan Department of Natural Resources Academy of Natural Resources at the Ralph A. MacMullan (RAM) Conference Center at North Higgins Lake State Park.  I am going through the process to earn an Environmental Education Certificate.  Actually, I am one of twelve people in the pilot cohort for this certification program. 

So just a photo for today.  This picture was taken this morning at the RAM Center.

Ode' imin Giizis and the Summer Solstice

Today, at 6:34 PM EST,  Spring ends and Summer begins in the Northern Hemisphere.  The moment this happens is known as the Summer Solstice.  The word Solstice comes from the Latin words sol (sun) and sistere (to stand still).  Today the sun has reached its highest position in the northern Sky, giving us our longest day of the year. 

The Earth rotates around its axis approximately once every 24 hours.  However this axis is tilted at 23.5 degrees from the vertical.  The points on the globe that the axis revolves around are referred to as the North and South Poles.  The axis is always pointed toward the same location in the sky.  The North Pole points toward the "North Star" - Polaris.

As the earth revolves around the sun, sometimes the North Pole is closer to the sun, sometimes the South Pole is closer to the sun.  When the North Pole is at its closest, we experience Summer in Mid-Michigan and the Southern Hemisphere experiences Winter.  When the North Pole is at its furthest, we experience Winter and the Southern Hemisphere experiences Summer. 

If you were to arise at dawn every day of the year and record at which point on the horizon the sun rises from you would be able to track the progression from the Summer solstice (in which the sun rises furthest North) to the Winter Solstice (in which the sun rises furthest South) and back again.  Tracking the postion of the rising sun was one of the earliest astronomical observations.  Many ancient monuments were constructed to act as solar observatories, recording the longest and shortest days of the year.


This year the solstice falls on the same date as the full moon.  This is a rare occurrence - the last such pairing occurred in 1948.  The full moon and solstice occurring within 24 hours of each other is less rare, but still uncommon.  The last time that happened was 1986.

You might hear people referring to this full moon as the "Strawberry Moon".  To Anishinaabe people in Michigan the Strawberry is known as ode' imin (heartberry) and the month of June is known as Ode' imin Giizis (Strawberry Moon).

In honor of the Solstice...

Sunburst and Lighthouse - A Photo from Northeast Michigan

Just a photograph for today. 

This picture of the Old Presque Isle Lighthouse was taken in 2009.  Old Presque Isle Light is located in Presque Isle Township in Presque Isle County.  Presque Isle County is located along the northern Lake Huron shoreline of Michigan's Lower Peninsula.  This light was originally constructed in 1840.  It was replaced in 1870 by the New Presque Isle Lighthouse. 

The words presque isle originally come from the French language and translate to "almost an island".  They are used to describe a peninsula that is connected to the mainland by a very narrow neck of land and is therefore "almost an island".  Presque Isle is one of many French place names in Michigan.  For approximately 150 years, Michigan was part of New France (Nouvelle-France).  Although Michigan was lightly settled by the French, it very important for control of the Great Lakes fur trade and fur trading posts/forts were established at strategic locations such as Detroit, Sault Sainte Marie, and the Straits of Mackinac.  Although the French ceded control of Michigan (and the rest of Nouvelle-France) to Great Britain in the 1760s, many of the place names have passed down to us today.

To learn more about these lighthouses visit the Presque Isle Township Museum Society website.

Old Presque Isle Lighthouse (July 2009)

 

Vernal Equinox 2016

Early Spring iris blooms in my garden (16 March 2016)

Yesterday at 12:30 AM (EST), Spring officially began for the Northern Hemisphere.  The date of the switch from Winter to Spring is known as the Vernal (Spring) Equinox.  On this date, the sun crosses over the celestial equator and begins to strike more directly on the Northern Hemisphere than the Southern Hemisphere.

If you were to rise each morning and observe the location of the sunrise from the exact same spot, you would find that the sunrise takes place in a slightly different location from one day to the next.  On the first day of Winter the sun would appear to rise far south of due east.

As winter progresses, the sun's position moves northward along the horizon a little bit each morning.  It will continue to move northward until the first day of Summer.  At that point each sunrise will move south along the horizon until the first day of Winter arrives again.  On the first day of Spring, the sun rises midway between these northern (Summer) and southern (Winter) maximums - the sun also rises at the midpoint on the first day of Fall (Autumnal Equinox).  Sunsets follow a similar pattern in the western sky. 

This shifting of the sunrise (and sunset) is due to the fact that the earth's axis is not directly perpendicular to the plane of its orbit.  If the earth's axis were perpendicular to the plane of its orbit, the sun would rise and set in the same location each day.  Instead the earth's axis is tilted approximately 23.5 degrees from the vertical - this is why globes are tilted.  For part of the year the Northern Hemisphere is tilted toward the sun (Spring and Summer) and for part of the year the Northern Hemisphere is tilted away from the sun (Fall and Winter).  Conversely, while the Northern Hemisphere is experiencing Summer the Southern Hemisphere is experiencing Winter; while the Northern Hemisphere is experiencing Winter the Southern Hemisphere is experiencing Summer.

Not only are the locations of the sunrise and sunset shifting, but the amount of daylight and darkness is also shifting.  On days when the position of the sun moves further north the amount of daylight grows slightly longer.  On days when the sunrise shifts southward the amount of daylight decreases slightly.

There are only two dates on which neither the Northern nor Southern Hemisphere is tilted more toward the sun.  On the equinoxes, both the poles line up with the direction of the earth's orbit and both hemispheres receive approximately equal amounts of daylight and darkness.

We are expecting snow later this week, but it officially Spring.  Get out there and enjoy it!

Who is Roy G. Biv and how does he control the color of the sunrise?

Red sun over Gratiot County

Have you ever wondered why the sun looks red or orange when it is near the horizon?  This morning on my drive to work I stopped to photograph the reddish-sun just a few degrees over the horizon.



The sun looks like this because of the properties of light.  The visible light spectrum (the light we can see) that comes from the sun is divided into seven colors red, orange, yellow, green, blue, indigo, and violet - ROYGBIV.  In order to remember the colors of the visible spectrum, just remember the acronym Roy G. Biv.

The colors that make up Roy's name are made of different wavelengths of light.  Red light has the longest wavelengths and violet has the shortest; the colors in-between have wavelengths in-between.

When light from the sun enters our atmosphere it is refracted (bent) and scattered by particles found in the atmosphere.  When the sun is overhead it has very little atmosphere to travel through so little of the light is scattered.  However when the sun is at a low angle such as near sunrise or sunset the light has to travel through more of the atmosphere before it reaches a viewer.  When it takes this longer path there is more opportunity for the light to be bent and scattered.

Colors that have the shortest wavelengths (indigo and violet) are scattered the most.  Colors that have the longest wavelengths (red and orange) are scattered the least, causing the sun to appear red or orange at sunrise and sunset.

Roy G. Biv watches the sunrise

To learn more about Roy G. Biv and the visible spectrum of light check out this post about rainbows from September 2014.