Mercury, Moon, and Mirages


Rising and Distorted Supermoon on New Year's Day

Happy New Year to all!  

New Year’s Day proved to be a busy one for sky sights from home in southern Alberta.

Clear skies and warming temperatures allowed me to capture a trio of sights on January 1: Mercury in the morning, a unique mirage called the Fata Morgana in the afternoon, and the rising Full Moon in the evening.

On January 1 elusive Mercury was at its greatest elongation away from the Sun in the morning sky. This placed it as high as it can get above the horizon, though that’s not high at all at the best of times.

Mercury in the Morning on New Year's Day
Mercury at dawn in the southeast sky.

I captured Mercury before dawn as a bright star in the colourful twilight, using a telephoto lens to frame the scene more closely.

At this time the temperature outside was still about -24° C, as a cold snap that had plunged the prairies into frigid air for the last week still held its grip.

But by the afternoon, warmer air was drifting in from the west, in a Chinook flow from the Rockies.

As evidence of the change, the air exhibited a form of mirage called the Fata Morgana, named after the sorceress Morgan le Fay of Arthurian legend. The illusion of castles in the air was thought to be a spell cast by her to lure sailors to their doom.

Fata Morgana Mirage on the Prairies
A Fata Morgana mirage on the Prairies

The mirage produced the illusion of bodies of water in the distance, plus distorted, elongated forms of wind turbines and farm buildings on the horizon. The cause is the refraction of light by layers of warm air aloft, above cold air near the ground.

By evening the mirage effect was still in place, producing a wonderful moonrise with the Full Moon writhing and rippling as it rose through the temperature inversion.

As the lead image at top shows, at moments the top of the disk had a green rim (almost a distinct green flash), while the bottom was tinted red.

Here’s a short time-lapse video of the scene, shot through a small telescope. The lead image above and below is a composite of four of the frames from this movie.

Rising and Distorted Supermoon on New Year's Day
A composite of 4 exposures of the rising Full Moon on New Year’s Day, 2018, rising from left to right over a snowy prairie horizon in southern Alberta. This is a composite of 4 out of 500 images shot for a time-lapse sequence, layered in Photoshop. All were with a 66mm f/7 William Optics apo refractor and Canon 60Da camera firing 1/25th second exposures every 1 second.

This was also the largest and closest Full Moon of the year, what has become popularly called a “supermoon,” but more correctly called a perigean Full Moon.

A lunar cycle from now, at the next Full Moon, the Moon undergoes a total eclipse in the dawn hours of January 31 for western North America. This will be another misnamed Moon, a “blue Moon,” the label for the second Full Moon in a calendar month.

And some will also be calling it a “supermoon,” as it also occurs close to perigee – the closest point of the Moon to Earth in its monthly orbit – but not as close a perigee as it was at on January 1.

So it will be less than super, but it will nevertheless be spectacular as the Full “blue” Moon turns red as it travels through Earth’s shadow.

— Alan, January 2, 2018 / © 2018 Alan Dyer / amazingsky.com

 

Evening Stars Over the Red Deer River


Evening Stars Over Red Deer River

Mercury and Venus shine as “evening stars” over the Red Deer River in southern Alberta.

What a fine night this was for nightscape shooting. Mercury and Venus are both now about as high as they will get for the year in the evening sky from my western Canadian latitude.

Venus is easy to spot as the brilliant object in the west. But Mercury is more elusive. You can see it here low in the twilight glow and much dimmer than Venus.

The photo illustrates how far each of the two inner planets swings away from the Sun in our skies, and why Mercury has its reputation for being difficult to sight. Also, it appears at its best for only a couple of weeks at a time. By mid-May it will be gone.

Venus, however, continues to dominate our western sky for the next two months.

I shot the main photo from the deck of a rickety wooden bridge over the Red Deer River near Dorothy, Alberta, just off Highway 10 east of Drumheller in the Badlands.

The image is a high-dynamic-range “HDR” stack of five exposures.

Venus over the Atlas Coal Mine

Shortly after taking the lead photo, I drove west to the Atlas Coal Mine to shoot it by the light of the now high and nearly Full Moon. Mercury can still be seen low and to the right of the historic tipple building. Venus shines above it.

This is a single 25-second exposure at ISO 800.

The Atlas Coal Mine is now a National Historic Site and is the last standing from what was once a booming coal mining centre in the Red Deer River Valley.

Now, mostly dinosaur fossils are unearthed here.

– Alan, May 3, 2015 / © 2015 Alan Dyer / www.amazingsky.com

Mercury Rising Over Calgary


Mercury is elusive but here it is, showing up as a speck over the skyline of Calgary, as it begins its best evening appearance of the year, rising a little higher into the twilight sky each night for the next few evenings.

To find it, follow the line down from the Moon and then bright Jupiter and Venus at upper left and continue that line to the lower right. Just to the right of the tallest building (the new Bow tower) and just above the rooftops there’s a tiny dot of light. That’s the inner planet Mercury. It’ll get higher in the first week of March but not by much. Mercury is bright. It’s just not very high and is easy to miss.

But with Mercury coming into view, and with Venus and Jupiter so prominent now in the evening, and Mars now bright in the east after sunset – look for a red star – we have a nice array of 4 naked eye planets across the sky at once. Saturn comes up later after midnight now. So you can see 5 naked eye planets in one night.

It’s a great evening sky show now in early March.

– Alan, March 1, 2012 / © 2012 Alan Dyer