IC 1396 – The Amazing Sky

December 20, 2014December 20, 2014

A Cosmic Christmas Wreath

A cosmic Christmas wreath glows in the sky, adorned by a celestial garnet.

This nebula, known as IC 1396, shines in the constellation of Cepheus the king, now high overhead on early winter evenings in the northern hemisphere. It’s a bubble of gas blown by new stars amid the interstellar wreath.

At top, shining like a Christmas light on the wreath, is an orange star. This is Mu Cephei, also known as the Garnet Star. It’s a red supergiant, roughly 1,500 times bigger than our Sun. If it replaced our Sun at the centre of our solar system it would engulf all the planets out to and including Jupiter.

Be happy Mu sits 1,000 light years away!

Happy holidays! And happy solstice. Winter arrives in the northern hemisphere at 6:03 p.m. EST on Sunday, December 21. That’s the shortest day and longest night of the year, for all those north of the equator.

September 30, 2013

King and Queen of the Sky

Cassiopeia and Cepheus reign over the autumn sky amid the Milky Way.

This is a photo from last night’s shoot, taken on a very clear autumn night with the Milky Way prominent across the sky. I shot sets of constellation images, among them this one framing Queen Cassiopeia and King Cepheus.

Cassiopeia is the well-known “W” pattern at lower left. Cepheus is harder to pick out – he’s a crooked square at right, topped by a tall triangle, like a child’s drawing of a house.

The Milky Way runs across the frame, peppered with red nebulas, from IC 1396 at far right in the bottom of Cepheus, to the NGC 7822 complex at centre, and the IC 1805 complex at far left. Lots of smaller nebulas dot the scene. At far left is the Double Cluster, two adjacent clumps of stars in the outer Perseus Arm of the Milky Way. Most of the deep-sky objects in this frame lie thousands of light years away in the next spiral arm out from the one we live in, or in the space between the two arms.

Most of the bright stars here are young blue stars. But a couple of exceptions stand out: yellow Shedar (or Alpha Cassiopeiae, the bottommost star in the W and an orange giant), and red Mu Cephei, at far right bordering the round IC 1396 nebula. That star is also known as Herschel’s Garnet Star. It is a red supergiant star 1400 times larger than our Sun and one of the most luminous stars in the catalog.

September 25, 2012September 25, 2012

Star Birth Site

In contrast to last Saturday’s post, Star Death Site, this is a place where stars are born.

This magenta cloud is where dozens of new stars are forming. One centre of star formation is the finger at right jutting into the hollowed out core of the nebula. Ultra-violet radiation from nearby hot stars is eroding away this dark finger of dust and gas, causing its rim to glow. This is a feature similar to the famous “Pillars of Creation” depicting in Hubble Space Telescope views of another nebula, the Eagle Nebula. However, this giant wreath of hydrogen 3000 light years away has no name, just the catalog number IC 1396. It’s in Cepheus, high in the northern autumn sky.

An added attraction of the scene is the orange star at top, Herschel’s Garnet Star, a.k.a. mu Cephei. This red supergiant is one of the largest stars known. If it replaced our Sun the Garnet Star would engulf all the planets out to Jupiter. Including its profuse radiation emitted in the infrared, the Garnet Star outshines the Sun by 350,000 times. It is squandering its energy so quickly this supergiant is destined to explode as a supernova, perhaps leaving behind a remnant like the Veil Nebula I described in that earlier blog from a few days ago.

These deep space wonders are all part of the great cycle of stardust that fuels the Galaxy.

August 25, 2012

The Subtle Shades of Cepheus

The Milky Way in Cepheus presents a palette of colours revealed in long exposures.

This binocular-sized field contains the large magenta nebula IC 1396, a site of star formation. On its northern (upper) edge shines the orange star Mu Cephei, otherwise known as Herschel’s Garnet Star, for its very red appearance in the eyepiece. It is a bloated red supergiant, one of the largest stars known. A few other stars in the field are younger blue giants. Faint wisps of red hydrogen fill the field (the faint crescent at right is Sharpless 129, left of centre is Sharpless 132, at top left is NGC 7380). Diagonally along the Milky Way lie dark, yellow-tinted dust clouds. The darkest patch at centre is the Barnard 169/170/171 complex. These contrast with the dust-free blue starfields of the Milky Way at left.

This is a stack of five 5-minute exposures with the 135mm telephoto and Canon 5D MkII camera, which has been filter modified to record the faint red nebulas better than a stock camera.