Tuesday, May 14, 2013

Two Scorpions in 10 hours

I recently had some time in the desert to watch scorpions. The first was expected: Scorpius, a favorite constellation of the summer sky. This time of year, Scorpius rises in a upright position. By midnight, you can see all but part of its tail.

The next morning I was blessed with the visitor that inspired this constellation:

Scorpion with size 12 shoe

This is the first scorpion I've ever seen. Online searches for "California Dune Scorpion" reveal a lot of photos showing a very similar creature.

A close up of my visitor whom I believe to be Smeringurus Mesaensis,
the California Dune Scorpion

Scorpion enthusiasts report this as a very fast moving scorpion, that is, quick to scurry away. They also describe it as a bit passive, more likely to hide than sting. This one was in no hurry. Instead, it kept a slow and steady march toward my car. I suspect that it took refuge under my vehicle and felt exposed when I pulled out of my campsite. It appeared to be trying to return to the vehicle's shade. I was able to get my photos and persuade it to choose a different direction, so that I could leave without worrying about driving over it.

Scorpius reinterpreted thanks to my campsite visitor


Tuesday, May 7, 2013

Dark Horse of Midnight

Last weekend's star gazing at Palomar Observatory Campground had probably the darkest sky I've ever seen at this location. The reason? We were expecting a storm to move in on Sunday, and during Saturday night, the clouds covered the nearby cities for a few hours before covering the mountain top.

At 1:00 pm, looking south at the Milky Way, you could detect dustlanes that look like a horse standing above the back of Scorpius.  I've never seen this before.  Double-click the photos below to enlarge the image, if necessary. The horse is diagrammed in the third image along with Scorpius. 

A wide field, portrait view.

A crop of the above photo.

The horse drawn (pun intended)


Omega Centauri

From our position in the solar system, Omega Centauri is the brightest of the globular clusters, which are dense packs of gravitationally bound stars forming clusters that are billions of years old. Some theories suggest that globular clusters are remnants of galaxies that have been eaten by our own.

Omega Centauri is best seen from the Southern Hemisphere, but in May, obervers at low lattitudes of the Northern Hemisphere get a glimpse of it skirting the southern horizon. The following photos show Omega Centauri in a gap of trees on my southern horizon.

Omega Centauri emerging from one tree and going behind the next.
(80 seconds, F4, 400 ISO, 70 mm focal length)

After adjusting the camera (during which Omega Centauri moved noticably) I resumed tracking of the object through the gap in the trees. (120 second, F4, 400 ISO, 70mm focal length)

Last best exposure before I lost it in the trees. (120 second, F4, 400 ISO, 70mm focal length)

These photos were taken at 10:43, 10:53, and 10:56 PM, when Omega Centauri was due south. I highly recommend that anyone with a low southern horizon look for this object now with binoculars or a small telescope. In general, any object appears two hours earlier the following month, so this weekend, Omega Centauri, it should be due south at approximately 10:30 pm.

Find Omega Centauri's general region by using corvus (right in the image below) as a pointer. Depending on the clearance of your horizon, you may also see scorpius in an upright position (left).

The dotted line shows the path of Omega Centauri. Scorpius on the left and Corvus on the right can be used to find the general location.


Saturday, May 4, 2013

I contributed a cartoon to a recent post on Skeptical Science (Forks in the Road: Last Exit to Two Degrees):

The Road to Six Degrees

The illustration reflects a common view among climatologists that the longer society waits to cut greenhouse gas emissions, the harder it will be to avoid a warmer planet. The turns in this metaphor are last chances. Every year, humanity is committing itself to an ever warmer world.

I think we've missed the two degree turn, but that's a debatable question. It's a genuine topic of scientific debate as opposed to the false controversy perpetuated by some conservative media, politicians, business interests, and most important, the conservative media's loyal followers. While the false controversy asks "is the planet warming?" "is it natural?", climatologists are debating how much Earth will warm and how that will play out on a world of 9+ billion people who are highly dependent on our climate.

For perspective, the average temperature difference between the last global ice age and now is 6 degrees C. Humanity is on the road to 6 degrees C, but in the warmer direction, a level that has not been seen in over a million years, perhaps many more. Worse, the rate of global change may have no precedent in geological history, but this too, is a valid scientific debate.

I'm ready to jump out of the car.


Thursday, May 2, 2013

Too Busy to Read my Own Blog

Too busy to read my own blog is the best way to describe me in Spring when most of our local schools have their star parties and other astronomy-related events begin (e.g., Explore the Stars).

My astronomy club (TVA) has been sponsoring the astronomy clubs at two middle schools in Murrieta, as well as trying to get these schools to setup their 16-inch telescopes in observatories. The former task is simpler than the later, being done my fellow member Paul Kreitz and me. The second project is driven mainly my our club president Mark Baker, and involves more bureaucracy since new construction is involved.

Each year I try to develop a new show for these schools, and each year I dabble in more complex subjects. This year, however, I got back to basics. Since I didn't have time to develop a new topic, I just refined a few favorites and re-learned that for the most part, middle school students and their families don't need to see intellectual growth from me, but rather, would like a simple subject that they can sink their teeth into. These factors lead me to revisit constellations.

Never underestimate how much people enjoy knowing what constellations are passing overhead, especially if these constellations are well known and include animals and zodiac signs. These most common of constellations are routine to amateur astronomers, but a joy to the general public. Below are some constellations of the Spring sky (in early evening) that I've been sharing at this year's star parties:

Look low, low in the West:
Here's orion and Taurus, which are low in the western horizon and must be viewed just after sunset.

Here is how I see Taurus. I diverge from the standard portrayal of Taurus, which draws impossibly long and U-shaped horns, a feature I find to be cruel.

And here is Orion, the aggressor the hunter. I didn't draw the shield of Orion because I, in my own interpretation, consider the shield area to be in disputed territory between Orion and Taurus.

Ok. Here's the shield, in agreement of standard sky maps that have sided with Orion:

But, everytime I look at Taurus and try to trace the figure, I get this:

The shield, to me, is more convincing as the haunches of Taurus. Though this is how I see Taurus, please note that I've borrowed a piece of Orion, and my interpretation is in conflict with star maps. Use or post on the internet at your own risk.

Here's a wider field of Orion and Taurus taken from backyard. That's my chimney you see.


Orion, the Aggressor:

And Orion's faithful hunting dog (Canis Major), safely guarding the rear, like most family dogs I know would:

Now Look Overhead, slightly to the south.

Another animal shape sits high in the Spring sky and is often considered the centerpiece of spring for its abundance of galaxies.

It's Leo, the Lion:

Leo is most easily found by it's sickle shape, a reverse question mark:

 Here are the main brightstars of the lion:

And here is the lion in it's Sphinx-like pose:

I see a lion in profile; official star maps may differ

And Now Look East.

The dominant constellation in the east is the Big Dipper, which is readily recognized by most people.

That was the easy part. But Ursa Major means "Big Bear", so where is the bear?

On a clear night, if you can ignore the stars of the handle and the bowl, the remaining stars make a remarkable bear shape:

But what about the tail? Forget the tail. Some Native American legends refer to the handle stars as hunters chasing the bear. They chase the bear around and around the north pole. It can go on for centuries till someone redraws the constellation.

The dipper does offer a useful metaphor:

In Spring, the dipper is tilted upword as shown in these photos and rotates into an upside-down position. What happens to water in an upside-down dipper? This represents the spring rains that are typical of most of the northern hemisphere (but not the Southwestern United States, where I live):

Those of you enjoying the Midwest's unusual May snowfall can pretend the water drops are snowflakes.

Of course, the big dipper is not complete without it's north star guidance system:

Though Polaris, circled in thie above image, is the north star, it is off of true north by a little bit. I think my circle's center point is a little closer to true north. 

Out of fairness, a look at the big dipper should include a look at the little dipper, or Ursa Minor, the Little Bear:

Which really doesn't look much like a bear, or a dipper.

Actually, it looks as much like a bear as any other random area of sky on a dark night.

In the really dark nights, the bright stars of constellations get overwhelmed by the abundance of fainter stars. This can be confusing and liberating. Confusing in that it's a little harder to find the familiar constellations; liberating, in that you have more dots to connect to follow anything you see in your imagination.