Bug-Eyed Over The Milky Way

A time exposure of the southern Milky Way and the planet Saturn (upper right) Saturday night caught a firefly with a double-flash pattern. Credit: Bob King

Boy, it’s a buggy time of year. Standing under an incredible Milky Way, I tried to picture all the insects between us and the stars — wayward moths, fireflies shaking green lanterns, mosquitos out for blood, spiders riding silk parachutes and many others too small to alert the senses.

Our planet is so intensely alive. July nights make you even more certain that life, so incredibly infectious, is busy eating and procreating on a million alien planets.

The Milky Way around midnight in mid-July crosses the sky from northeast to southwest. The Northern Cross is near the top with Sagittarius at the bottom. The Great Rift splitting the band in two is opaque interstellar dust blocking starlight from behind. The green and pink colors are airglow; the yellow at the bottom is city light pollution, and the thin green streaks, firefly trails. Credit: Bob King

That’s probably how many planets hung overhead every single one invisible except the familiar faces Jupiter and Saturn. This is time of year you’re going to see more stars in the sky than any other season. Winter gets billed as best for stars. It is if we’re only talking the greatest number of bright stars, but if you go by total number, July’s got winter beat by a million miles.

In summer, we’re facing toward the center of the Milky Way Galaxy, where the stars are far more concentrated than in winter, when we look out toward the edge of the galaxy and into intergalactic space.

Stars concentrate in the Northern Cross (seen here on its side with Deneb, the brightest star, at left, and Albireo, the foot of the cross, at middle right), in a fist-and-a-half-wide oval of stars called the Cygnus Star Cloud. When we look in this direction, we see down our local spiral arm where it wraps around the center of the galaxy. Stars pile up along our line of sight that’s easily 8,000 light years long to create the oval. Credit: Bob King

The Milky Way begins humbly in the far northern sky Perseus and the W of Cassiopeia and flows south through the Northern Cross, where it puffs up to become the Cygnus Star Cloud, an oval concentration of stars right at the naked eye limit that begs to be observed in binoculars. South of here, the milky band splits down the middle and continues through Aquila the Eagle and down into the Teapot (Sagittarius).

When packing up the telescope at the end of Saturday night, I was surprised to see this moth perched atop one of my eyepieces. Credit: Bob King

All along the way, stars are gathered in great billows or in small knots of star clusters or clusters wrapped in gaseous clouds called nebulae. Many are visible in ordinary binoculars. I find wide-angle 10x50s best for Milky Way observing because they offer good light gathering power and resolution while still being easy enough to handhold.

The next couple weeks will be ideal for Milky Way observing with the moon out of the sky.

A final note about last night’s aurora. It really did make an appearance, but by the time it showed (very late), it had shrunk back north and was only visible as a glow extending about 10° above the northern horizon. Too bad. So many of us anticipated a much bigger display. Just goes to show you, we still don’t know the aurora well enough to predict its behavior with anything close to precision.

6 Responses

  1. Jeannette

    Bob, I was up and down all night looking for the aurora..no WI with a good North view.
    Did it materialize?
    A fan, Jeannette

    1. astrobob

      Hi Jeanette,
      Yes, it did but sadly didn’t amount to much. I saw nothing around 11:15 but at 12:30 a.m. there was a low, diffuse glow across the north. My camera recorded a single faint ray. It fired up again around 4 in dawn (I was asleep) but never went wild like it did during the afternoon hours.

  2. Hi Bob. I always enjoy your posts. Thanks for mentioning pleasant insects like fireflies & moths even when you are plagued by the less desirable sorts. We’ve got washed-out cloudy summer skies here in suburban Philadelphia. Albireo is a binary, correct? It was introduced to me as the Cub Scout Star because the pair contains one yellow & one blue star.

    1. astrobob

      Hi Jason,

      Thank you for your kind words. Sorry to hear about your skies – I can only imagine how bright it must be. Is there anywhere near Philadelphia that’s reasonably dark? Yes, Albireo is a binary but one with a very long period.

  3. Conrad Smith

    Bob,

    This is my first time writing a note…would like to say that I love your columns! Secondly, and I am sure you have this information somewhere else but I am not sure where to look, what equipment do you use for your photographs? They are great sky shots, and I have tried to take decent photos of the nighttime starfield, but mine just don’t turn out very well…Nikon D70 with standard lens here. Thanks!

    1. astrobob

      Hi Conrad,
      Thank you so much – I’m happy you enjoy the blog! I use a fairly high-end camera, a Canon 5D Mark II and a fast lens (f/2.8) when shooting at night. In the photos that show the billows of the Milky Way, I’ll put the camera on a motorized mount to take time exposures to avoid star trails. For aurora I shoot either at ISO 800 or 1600. For wide-angle, night sky Milky Way photos (no motorized mount), I use ISO 1600. I carefully focus on a magnified view of the stars using the camera’s live view feature.

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