SkyCenter StarGazing

Our final night in Tucson was special because it was something we had wanted to do for a very long time. We attended a stargazing session on the top of Mt. Lemmon, a 9,157-foot mountain that looms over Tucson and is home to the University of Arizona’s Mt. Lemmon SkyCenter, which is part of the Steward Observatory.

Telescopes

For $65.00 per person, we spent about five hours at the observatory learning about the heavens and looking through the 32-inch Schulman telescope.

Schulman telescope

The program comes with LOTS of instructions …

You must bring warm clothes -- they really STRESS this. From their emails, you would assume that it is subarctic and, I suppose, wind could make it pretty miserable. My guess is that folks visiting or from Arizona just don't get that, even though it is close to 90 degrees in town, a jacket, gloves and hat are necessary at the top. I came prepared, with snow pants, crampons, massive mittens and all, but I didn't need most of it. It was a balmy 43 degrees with light wind.

Along the road

They make it clear that you must be ON TIME or the bus from the parking lot to the observatory will leave you behind. It's a 60-90 minute drive up a winding road (with some pretty views), so extra time is a good idea. The drive was event-free, so we had to wait a while for the bus. Rob, our presenter, was personable and informative. A physicist rather than an astronomer, he does the presentations more as a hobby than as a job. 

He also drives the bus. In the daytime, it means contending with winding roads. At night, it means driving those roads with no lights so as not to disrupt the telescopes!

The event provides a light dinner, binoculars treated with a coating to use with night skies and lots of chances to look at the heavens.

Orientation lecture

We started by going to the dome that encloses the telescope for an orientation.

It was still light when we started

The research arm of the Department of Astronomy at the University of Arizona, the Steward Observatory was established in 1916 and the first telescope and building were formally dedicated in 1923. It now operates, or is a partner in, telescopes at five mountaintop locations in Arizona, one in New Mexico and one in Chile.

The observatory is one of the things the University is known for

The Steward Observatory has operated astronomical facilities on Mt. Lemmon and nearby Mt. Bigelow since 1970. Major projects have included the survey of the Moon for Apollo lunar landings and the ongoing search for near-Earth asteroids.

The Steward Observatory Field station hosts a total of nine research and educational telescopes at the Mt. Lemmon summit and at Mt. Bigelow, ranging from 24 to 61 inches.  One of the telescopes belongs to the Korea Astronomy and Space Science Institute (KASI) and is operated remotely from South Korea.

It suddenly moved while we were there

In 2008, Adam Block and the University of Arizona College of Science launched the Mt. Lemmon SkyCenter to present educational activities including public evening observing programs, summer programs, workshops, camps, remote observing and special educational events. Our event was part of that program.

Impressive

During the daylight orientation, we actually saw a star (Sirius) through the telescope in full daylight. That was cool. And, we saw – on the computer screen so that we didn’t blow out our eyeballs – the telescope's view of the Sun.

A star in the daytime

We headed back to the education center for some lecture, Q&A and dinner. Then, back out to observe sunset from the mountaintop. 

Sunset

We marveled at our blue shadows, which we learned were caused by "Rayleigh scattering." which happens because shorter (blue) wavelengths of light scatter more effectively by the molecules in the air than longer (redder) wavelengths. On Mars, where the sky is a bit more pink, shadows would be pink as well.

Blue shadows

After the sun went down, we started our telescope observations.

Although some were very difficult for me to see with my funky eyesight and trifocals, it was very impressive. Throughout the evening we saw (although not nearly as clearly as these illustrations and usually in shades of gray or pastels rather than in brilliant colors):

Almach: The 3rd brightest star system in the Andromeda constellation. When viewed through the telescopes at the SkyCenter, it appears to be a bright yellow star (Almach A) next to a dimmer blue star (Almach B). Almach A is approximately 1,500 times brighter than our Sun.

It was later discovered that the dimmer greenish-blue star is in fact a triple star system. 

What appears as a single star to the naked eye is a quadruple star system, approximately 350 light-years from Earth.

Crab Nebula: A remnant of a supergiant star that exploded 7,300 years ago. 

It has complex interwoven tendrils of gas and dust -- the ever-expanding and interacting remains of the rapidly rotating (30 times per second) pulsar at its center. 

The stellar explosion that produced the nebula contained all of the elements heavier than hydrogen and helium. 

These heavy elements are formed by stars and it is only through their deaths that the elements are scattered throughout our galaxy to perhaps coalesce into planets and people. to us, it looked like a cloud or smudge.

Eskimo Nebula: A bipolar double-shell planetary nebula discovered in 1787. Seeming to show a "face" surrounded by a circular fur hood, the Eskimo Nebula is in the constellation Gemini and is 2,900 light-years away. 

Hubble Telescope images  show gas clouds, ripples, shells, knots, filaments and cometary heads that are so complex they are not fully understood. 

This looked like a smudge with a bright star in the middle.

The Pleiades: A striking open star cluster that formed 75 to 150 million years ago. It is among the nearest star clusters to Earth and is visible in the evening during the late fall and winter. 

Most people can see six or seven stars with the unaided eye. Binoculars reveal a cluster of young stars, which actually contains over 1,000 confirmed members.

The Pleiades also carry the name "Seven Sisters" for the seven daughters of the titan Atlas and the sea-nymph Pleione. Their Japanese name is "Subaru," which was taken to brand the car of same name (notice the stars on its logo).

The Great Andromeda Galaxy: A classic spiral galaxy very similar to our own. 

At only 2.5 million light-years away, it is our closest neighbor galaxy. I had no idea you could actually see a galaxy, but there it was in the telescope eyepiece. And some people can even see this one (as a tiny smudge) with their naked eyes. Although a smudge, it really did look like a galaxy. A galaxy!

Binary Star: Two stars that are physically close and gravitationally bound to each other with distinctly different colored stars. The brighter amber/yellow star is actually a binary itself, while its blue/green companion seems to be solitary. 

It's not even known if the two major stars are gravitationally related to each other; if they are, a complete orbit would take over 100,000 years.

The Orion Nebula (the coolest thing of all): Glowing gas surrounding hot young stars at the edge of an immense interstellar molecular cloud 1,500 light-years away. It is also known as M42.

Scott was disappointed because you can’t see colors, just shades of black and gray. These photos are black-and-white images with the colors accurately reapplied in a process similar to PhotoShop.

But to see a nebula with your own eyes is amazing. It actually looked just like a black-and-white version of this.

Thor's Helmet: An emission nebula in the constellation Canis Major. The nebula is approximately 15,000 light-years away and is very faint. I could not make it out, no matter how much I tried to focus the eyepiece or squint. 

So, I just had to take Rob's word that is was there. He said that he could see it.

Jupiter and two of its Moons: he gas-giant planet, fifth out from the Sun, is the largest in our solar system. 

Jupiter was turned (or, more accurately, we were turned) so that we couldn’t see the iconic Great Red Spot "storm," but the stripes across the planet's surface were very clear. 

Unlike this image, the Moons were very prominent, looking like sparkling stars right on the edge of the planet. But, Jupiter looked exactly like this (color and all)

Uranus: The seventh planet from the Sun, Uranus is 15 times the mass of the Earth, orbits at 20 times the Earth's distance from the Sun and takes 84 years to orbit the Sun. Unlike all other planets in our system, Uranus' axis of rotation is nearly perpendicular to its orbit. 

Of course, it looked like a bluish star, not like this.

M37: A cluster of as many as 500 stars. At a distance of between 3,600 and 4,700 light-years, its 150 stars brighter than 12.5 magnitude include a dozen red giants. 

These types of clusters can be seen with the naked eye, with a great deal of detail available through binoculars. 

But, the telescope really reveals the unfathomable number of stars

Honestly, it is hard to remember seeing all of these (and some I couldn’t make out), but the most impressive were the Orion Nebula, Jupiter and the star clusters.

It was a long night. Ninety minutes down the mountain in the dark could be daunting for non-mountain folks, but it is a nice road and it was a dry night. We were a bit surprised at how much light Tucson produces, despite being a dark-sky-friendly city. Rob said that the light pollution had increased in recent years, but still doesn’t negatively affect the observatory. 

We had hoped to take some true dark sky photos, but it was too light for that.

Night sky

Not bad, but not as dramatic as we were hoping for.

Trip date: February 22-29, 2016