Seven Sisters – The Amazing Sky

April 9, 2015

Heads Up! – Planets Pair with Clusters

Look west and south this weekend to see the two brightest planets each pairing with a bright cluster of stars.

This weekend, Venus and Jupiter each pair with a prominent open star cluster.

In the west, look for brilliant Venus, an evening “star” this spring, shining near the Pleiades, or Seven Sisters star cluster. Some know it as Messier 45.

Both Venus and the Pleiades are in Taurus the bull, whose main stars lie to the left of the Venus-Pleiades pairing. Farther to the left still, look for the distinctive stars of Orion the hunter, whose trio of Belt stars give him away.

As this close up shows, binoculars will nicely frame Venus and the Pleiades at once.

Venus continues to climb higher this spring while the Pleiades and the other stars of the winter sky, including Orion and Taurus, sink lower and lower. The next few nights are the best for catching Venus as it passes the Pleiades.

High in the south as it gets dark shines the other bright planet in our sky – Jupiter.

It, too pairs with a star cluster. Jupiter now shines a binocular field to the east (left) of the Beehive Cluster, also known as Messier 44. Jupiter and M44 lie in Cancer the crab, a faint constellation nestled between Leo to the east and Gemini to the west.

Jupiter has been retrograding closer to the Beehive all winter and early spring. But this weekend Jupiter sits as close to the cluster as it is going to get. For the rest of spring and summer Jupiter will move east away from the Beehive.

Look west and south as it gets dark this weekend, for the pair of planet-cluster pairings!

Clear skies and happy stargazing.

January 18, 2015

Lovejoy Passes the Pleiades

Tonight Comet Lovejoy paired with the Pleiades star cluster.

Sunday, January 18 was the night to catch the ever-photogenic Comet Lovejoy at its best and closest to the Seven Sisters, the Pleiades. Its long blue ion tail stretched back past the Pleiades.

I thought the tail would be passing right over the star cluster, but not so. At least not when I was shooting it at about 7:30 pm MST.

Still, the combination made a fine pairing of cosmic blue objects for the camera. The top image is with a 135mm telephoto.

This wide-angle image, with a 24mm lens, takes in many of the northern winter constellations, from Orion at bottom, to Auriga at top, with Taurus in the middle. Notice the dark tendrils of the Taurus Dark Clouds.

At right, beside the Pleiades, is the green and blue comet, with its tail reaching back past the Pleiades.

I shot both images from the dark skies of City of Rocks State Park, New Mexico, which has proven to be one of the finest places on the planet for watching Lovejoy!

November 19, 2014

The Seven Sisters in a Silver Braid

“Many a night I saw the Pleiads, rising thro’ the mellow shade,

Glitter like a swarm of fireflies tangled in a silver braid.”

– Alfred, Lord Tennyson

These are the famous Seven Sisters, the Pleiades, caught two nights ago in New Mexico skies. This bright star cluster stands out easily to the unaided eye in the winter sky, shining in the shoulder of Taurus.

What the eye does not see is the “silver braid” – the dim dust that surrounds the Pleiades. The stars light the dust, causing it to shine blue near the stars. Farther out, the dust is much dimmer and glows with pale tints of cyan and red.

The dust clouds were once thought to be what was leftover from the formation of the stars, now estimated to have occurred about 100 million years ago. However, current theory suggests that the natal dust of the Pleiads would have long since dispersed.

Instead, the silvery braids of dust that surround the Seven Sisters are just nearby dust clouds in Taurus that the stars are passing through, and illuminating with their hot blue light.

The Pleiades, as familiar as they are – they have been mentioned in ancient texts and myths dating back thousand of years – remain a source of scientific controversy. Astronomers argue over their distance, with different methods providing different results. But the best recent measurement puts them 440 light years away.

Technical notes: This is a stack of 10 x 12 minute exposures at ISO 400 with the Canon 5D MkII camera and 92mm TMB refractor at f/4.4. I shot the images November 16 from near Silver City, New Mexico.