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Spaced-Out Challenge: Taurus the Bull

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Taurus, from Bayer's Uranometria (1603)

Welcome again to the Spaced-Out Challenge. Whether you have a question about a scope, a new astronomical discovery you want to expand on, or just want to kick back and enjoy the cosmos above, come one come all on our weekly journey through space and time.
Our Winter Sky Guide continues with an animal fierce enough to keep Orion away from the Nymphs of Atlas & Pleione, Taurus the Bull. What Taurus lacks in quantity of objects it more than makes up for in beauty. Let me show you.

Finding Taurus and your way around the Bull
There are two popular depictions of Taurus from Greek myth: it's Zeus in disguise so he could travel to earth and woo women, or (and I'm more partial to this one) it is a guardian put up in the sky to protect the beautiful Pleiades from Orion's ravenous appetite. Cultures utterly alien to the Greeks worldwide see this intimidating constellation as a raging bull, as we discussed in last week's challenge, humans have viewed it as such since we started painting on cave walls.

Taurus is relatively easy to find in the sky, even from a light-polluted area, rising before Orion in the fall sky and dominating the night with the Great Hunter to his north and west:
View image
(too large to post here, see popout)

To highlight our targets in Taurus and to familiarize yourself with the constellation, here is a large popout giving you the lay of the land:

View image

Targets in Taurus

Aldebaran, the Bull's Eye

One of the brightest stars in the sky, it's striking red color is the result of the star's age. Aldeberan has moved off the main sequence of stars, it's hydrogen supply dwindling away, and as a result of pressure and heat forces, it has ballooned to about 44 times the size of our sun. Striking to the eye, beautifully framed against the more distant Hyades through a telescope, and it's fiery color glorious in a telescope, Aldebaran is one of the more memorable stars in the Winter Hexagon.

The Crab Supernova Remnant

On July 4, 1054 A.D., people around the world witnessed the sudden and spectacular appearance of bright new star in Taurus, just a degree from the southern horn star (zeta Tauri). It was so bright it shone during daylight hours for twenty-three straight days, and did not vanish from night-time naked-eye view until over 650 days later. We know such specifics because of it's impact on world cultures: the guest star was observed meticulously by Chinese and Arab astronomers, referenced by an 11th century Christian priest in Balkans, and even marked by the Anasazi in Chaco Canyon:

Chaco Canyon Petrograph originally painted by Dave in Texas

Considering the amount of energy involved in the catastrophic gravitational failure, it is a wonder anything remains of the star after it's Type 1A detonation.

Yet amateur observers, armed with a telescope of at least 3" aperture and an O-III filter, can see the end result as a faint, ghostly smudge just a degree away from Zeta Tauri. Owners of an XT8 or larger can actually see (in good conditions) the knotted shreds of the victim star within this smudgy cloud. Charles Messier recorded this remnant in the 18th century, including it in his famous list (it's object #1), though it has faded considerably in the 250 years since.

To find it, aim your telescope at Zeta with a low-power eyepiece, pop in an O-III filter behind your eyepiece, and gently roll around Zeta until it just barely pops out of view. With your eyes dark-adapted, you will notice a faint smudge of light. Crank up your power and take a peak.

Sketch from 3" instrument by Wes Stone

Sketch using a large dobsonian by Bernard Augier

For owners of even larger instruments, you may luck out in finding a faint "star" nestled within the nebulosity. While it appears to continuously shine, albeit faintly, you are actually looking at the zombie star within: the Crab pulsar. A millisecond pulsar spinning furiously, we have recently managed to image it blinking on and off:

Not bad for a neutron soup 12 miles across with a mass several times greater than the sun.

The Crystal Ball Nebula

Only gigantic stars can die in such a spectacular fashion, but even ordinary dwarfs like our sun can still leave a lasting impression as they pass on. Planetary nebulae, the final phase of the outer layers of a star like our sun, are these layers of gas expanding and dispersing away from the dying core, leaving an object that is planet-shaped and colored. One of the overlooked ones is in Taurus, near ψ Tauri. In the large map, find it and 41 and 44 Tauri north of the face and horns, and follow the map below:

The Crystal Ball is the middle of a row of 9th magnitude stars, and will appear haloed or smudged. But in a 4" scope or larger, add an O-III filter and crank up the magnification. The star will dim, but the faint nebulosity will pop into place in the shape earning it's name.

The Hyades and Hind's Variable Nebula

The "V" shape of stars around Aldebaran that form the bull's face are part of a large open cluster called the Hyades, visible to the naked eye (and spectacular from a dark site) and mentioned in Greek myth along with their more famous neighbors to the north, the Pleiades. While Aldebaran appears to be part of the open cluster, it is simply superimposed: at just 65 light years away, it is more than twice as close as the Hyades, which can still boast of its title of closest cluster to Earth.
A few degrees to the north of the Hyades is the variable star T Tauri, whose varying light illuminates a reflection nebula first discovered by astronomer John Russell Hind in 1852. If the night is clear and your instrument is large (at least 8" in aperture), give it a crack. It will appear as a faint wisp minutes from the star lighting it up.

The Crown Jewels of Taurus: The Pleiades

M45 by Antonio Fernandez-Sanchez

One of the few Messier objects that is bright enough to cut through the worst light pollution, The Pleiades, or Seven Sisters, are plainly visible as a smudge in city skies, resolving to a tight cluster in suburban skies, and are just stunning in a pair of binoculars or a small telescope. Owners of 3" refractors, rejoice: your view is more impressive than the owner of a large dobsonian.
A challenge when observing this wonder is to try to spot the faint nebulosity visible in photographs. The Merope nebula is the easiest to catch from a fairly dark location, and ads to the beauty of this open cluster.

For me, the Pleiades have no rival: they are the open cluster to observe. If tonight is clear, brave the cold and take your binoculars out and give them a good look. You'll quickly see why Orion had the hots for them.

***
The full Beginner's Buyer's Guide, our Comet Guide (featuring additional grab-and-go telescopes), and any other edition you're looking for can be found in the master index of all Spaced-Out Challenge threads here, but of course you can always inquire about binoculars, telescopes, and all the rest in the comments. As always, if you have astrophotography, product recommendations, or astronomy news you'd like to see on a future Spaced-Out Challenge, email me at theoneandonlyfinn (at) gmail.com, or tweet me @conartcritic.

Until then, clear skies and keep looking up!