Southern Stars

Southern Stars

I'm beginning a new chapter in my variable star work,  Since taking an astronomy course at GTCC in 1997 I've been making visual observations of variable stars for the AAVSO.  I haven't done many, but a few every year usually get added to my records.

This year I'm learning how to take images of the variable stars and calculating magnitude using computer software.  In addition, I will be looking at stars in the southern sky, stars unavailable to observers this far north of the equator.

My first target is to calibrate exposure time.  I've taken an 80 second exposure of the variable star u tuc.  It's found in the constellation Tucana (the Toucan). There are apparently many unknowns about this particular star, including it's distance from Earth and the period of variability.

Art and Astronomy

Art and Astronomy

A couple weeks ago a special group from Winston Salem came to visit Cline Observatory and look thru our telescope. They were young artists seeking inspiration.

Wednesday evening these young artists presented their work at the Southeastern Center for Contemporary Art in Winston Salem. It was exciting to see them excited about astronomy and present their thoughts and feelings and impressions thru their media. (I wish I understood art more.)

Located on the Jamestown campus of GTCC, Cline Observatory is open to the public, free of charge every clear Friday night. This week we are scheduled from 7 to 9 with a high probability of clouds or rain.

cloudy lunar eclipse

I was disappointed the sky was so cloudy Tuesday morning. I checked at 1:15 AM, and again at 3:00, and the Moon was not visible thru the clouds.

Tim, a buddy who lives about 45 minutes north of us, had more fortune. He snapped these images of the last lunar eclipse of the year. Our next lunar eclipse is scheduled for December 10, 2011. It will be only partially visible at moonset from the east coast.

Sharing the Moon

Greensboro has a nice new park downtown, and the site has become a magnet for folks and events. I took my 6 inch Celestron telescope to the park today for a couple of hours.

I was in the shadow of tall buildings for most of the hours I spent there. The Moon peeked above a building around 4 o'clock and other park patrons took turns looking thru the telescope. The Moon is currently just past 1st Quarter, and we could see the rugged southern area as well as the large mare on the western limb.

I got the usual questions about the size of the Moon and its distance from Earth, the relative distances to the Sun and the Stars, and so on. One guest was very knowledgeable and professed that he had done a good amount of research to support his belief that the world "as we know it" will end December 21, 2012.

I mentioned the 100% track record of such predictions being wrong, and he talked about the Federal Reserve Board and fascism. The Haitian earthquake, the increasing number of sunspots, and the Book of Revelations were all too much for him to dismiss, so he seemed firmly grounded in the "true believer" community.

The Tempest in the sky

Yesterday Barbara and I went to see a performance of the stage-play "The Tempest" by William Shakespeare. Barbara had encouraged her philosophy students to see this production of the NC Shakespeare Festival due to the connection with "Ship in a Bottle" from the Star Trek: Next Generation TV series. I just went along for the fun.

Then the names of some of the characters reminded me of astronomy:

Ariel, the air spirit and a major force in the story, is also the name of one of the smaller moons of Uranus. The solar system body is covered with impact craters and long rift valleys, Damaged not too unlike the character on stage.

Miranda is the name of Prospero's daughter in the play, a young woman easy to fall asleep and not very experienced when it comes to men. Miranda is also the name of another small moon of Uranus, the surface of which looks like a jumble of different features not carefully reconstructed.

Ceres and Juno are sprites in the Shakespeare comedy. They are also two of the four largest bodies in the main asteroid belt.

Isn't it wonderful that astronomy is almost everywhere?

Observing the Moon

Last night was International Observe the Moon night, and in celebration, I observed the Moon!

It was a grand evening with a guest list of about 50 folks, including movers and shakers of Greensboro (a former mayor was there!)

We looked at the waxing gibbous and talked about distance and American flags and a variety of other related and unrelated topics.

We took a peek at Albireo and spoke of color, temperature and mass.

Finally the giant of planets, Jupiter, rose above the trees and we spied the 4 Galilean moons.

Hope you got to look at the Moon last night. We saw 5.

If you missed it, tonight is not too late.

Three Planets plus at the Observatory

Last Friday the clouds played hide-and-seek, but the folks at Cline Observatory had some nice views of a globular cluster, the Bay of Rainbows on the Moon, and planets.

Venus was the first "star" to be found by a guest, a game we sometimes play. Venus is so bright and so high in the early evening sky, it is easily the evening star.

Mars was a rusty spot more difficult to discern. The clouds were not kind to us here.

Saturn's ring is slowly increasing it's tilt from our perspective. It was just last year that Saturn experienced "zero degrees inclination." We are now beginning to see more and more of the "northern" side of the rings as Saturn's north pole tilts toward us.

Senses

I grew up learning that we humans possessed five senses. Can you quickly name them?

touch

taste

smell

sound

sight

What is a sense? My handy dictionary says, among others,

"a specialized animal function or mechanism (as sight, hearing, smell, taste, or touch) basically involving a stimulus and a sense organ."

I just finished What If the Earth Had Two Moons? by Neil Comins, and he posits an interesting wrinkle to our understanding of senses. Comins writes that two other senses are usually left off the list taught to children, and they are "heat and gravity."

We can put our hand near a fire and feel the heat, but are we using the same sense organs (nerves) we use for touch? Does that make "feeling heat" a part of the sense of touch?

And what sense organs do we use for gravity? To sense when we are falling, do we use another sense organ other than our eyes (seeing the environment pass by) and nerves (feeling the wind, friction and impact)?

What do you think? Seven senses? Or five?

Lost in Space

This past Friday evening, Dr. Steve Danford (UUC-G) addressed the Greensboro Astronomy Club regarding the future of America's space program. Steve's always a good presenter, and he can even make sense out of the chaos we call NASA.

He shared a graphic from Dr. Harry Shipman (University of Deleware) that puts the major issues before us and guides us to logical conclusion.

If I read this correctly, if we find that some things are best made in space ("space industrialization") AND we find celestial resources to live independently of Earth ("Extraterrestrial Resources to Support Humans") we will see, sooner or later, full human settlement of outer space, with a thriving space station or two and some colonies on the Moon, Mars, and other locales.

If, on the extreme other hand, we find neither things to make in outer space, nor resources on which to live, we will have a future with robotic explorers and telescopes.

What do you think? Does this approach make sense?

Beauty of Saturn

One of the most popular sights at the Observatory is the sixth planet from the Sun, Saturn. Friday I had the opportunity to have dinner with a member of the Cassini Mission investigating this beautiful planet and her moons.

Dr. Anne Verbiscer from the University of Virginia shared this wonderful image taken by the space probe in September of 2006. This is the ringed planet back-lit by the Sun. Detected from this work were two new faint rings

You can see more by going to the Cassini Home Page at http://www.ciclops/org/index/php

Planets at the Observatory

Friday night at Cline Observatory can be a very fun evening. That's when we host a free public observing session, and the guests can view some really nice celestial objects.

This first Friday of April Angela and I opened the Observatory a little early to pick up Mercury and Venus in the western sky. Later in the session we spotted both Mars near our zenith and Saturn in the east. Four planets in one session is something to write home about.

We also got to see the Orion Nebula, binary stars (Sirius and Castor) and some clusters; a couple globular clusters and the Beehive Cluster. The guests were so into the observing we stayed open about an hour later than usual.

About 55 guests came to Friday's observing session. Tom and Steve set up a telescope out on the nearby pad to relieve congestion under the dome.

Do you believe in scientific evidence?

The importance of the meanings of words, and understanding of the shades of meanings of words is a theme in my reading lately. What is “science”? What do scientists mean by “knowledge”? What are good “models”? How do “theories” help us understand the physical world around us? (174)

One word I think is an important word for scientists to keep in mind is “belief.” I recently read a paper on science education, and the authors use the word in their introduction, and then hint at it later in the chapter. How do our students “come to understand …‘why we believe’ scientific evidence.”

Should scientists and science teachers use the word “belief”? Is there a better, more accurate word to use that can help avoid misunderstandings?

I tend to use the words “belief” and “believe” in spiritual and religious contexts. These words seem to me to be about an opinion, leading to a conclusion that may not have convincing supporting evidence. Of course, an extreme skeptic may never find enough convincing evidence, but a healthy skepticism can be addressed, I believe, with satisfactory observations and reasoning to reach conclusion.

I may not be able to share enough evidence to convince a skeptic of the existence (or non-existence) of God, but the evidence supporting a geocentric model of our solar system appears conclusive.

Does use of the word “belief” in a science context make understanding science more difficult? When the authors write “why we believe scientific evidence” are we shortchanging the scientific basis of our models and maybe even doing religious beliefs a disservice? I think so.

So what can we do? What should we do?

Even though they are only words, and different shades of meaning can be compounded by context, I think we can use a more accurate word than “belief” and I encourage my astronomy students to consider using this other word in scientific context.

I “think” the Earth is spherical. Biologists “think” evolution best describes the changes seen over time. Geologists “think” plate tectonics have been shaping the surface of our Earth.

I try to use the word “think” in my classroom and in scientific discussions. Sure, I backslide and use the “b” word every now and then, but when I use “think” in class, I think my students understand the important difference in meaning.

#

The beginning of Spring

The image above is rainy Roger Dean Stadium, Jupiter, Florida, March 12, 2010.


Astronomically, Spring usually begins around March 21.

The Earth is tilted on its axis, relative to the plane of its orbit around the Sun. Sometimes our northern hemisphere is tilted toward the Sun (that's our summer) and sometimes we're leaning away from the Sun (our winter.)

In between, we find Spring and Fall.

So around March 21, the Sun reaches the celestial equator on it's slow slide higher in the sky. That's the official beginning of Spring, the Vernal Equinox.

But this week I got to attend my first Spring Training games of the baseball season. While we focused on the Cardinals and Mets, we got to see other teams, too.

Monday: Mets 11, Marlins 2
Tuesday: Astros 8, Mets 4
Wednesday: Nationals 4, Cards 6
Friday: Red Sox v. Cards Rainout

The image at the top is rainy Roger Dean Stadium, Jupiter, Florida, March 12, 2010.

("Sometimes you win, sometimes you lose, sometimes it rains. Think about that for a while." Ebby Calvin "Nuke" LaLoosh in the movie "Bull Durham")

So for me and Barbara, experiencing game-time temperatures in the 70's, our Spring began this week.

Friendly Stargazing

A couple nights ago I gathered with some friends in the country and put my new little telescope thru it's paces. I've got a Celestron NexStar 5 inch telescope with wonderful go-to capabilities. We had a great time and saw many beautiful celestial objects.

The go-to is so decadent. I use to have to know where I wanted to look in the sky as well as what I wanted to look at. Now, with go-to, I only need to know what I want to observe. A friend with binoculars was tenacious about find the same objects. Of course she used my 'scope as a clue, but she sometimes had to really search the sky. Is that a skill that will be lost with go-to-capability? Will it matter?

My scope also tells a little information about the selected celestial objects. At the beginning of the evening I would read and paraphrase what the computer said for my friends standing around. Would you tell them that you're reading from the computer or let them continue to think think you're that knowledgeable? When does it become deception?

We had a great time with a near-first-quarter moon, M42, Mars and Saturn, lots of questions, lots of friends plus much more.

Some of my favorite questions at this star party:
1. Do I believe in aliens?
2. Can stars change over time?
3. Why did NASA secretly crash a probe onto the far side of the Moon to look for water?

Making a Comet in Class

Thursday in astronomy class we made a "comet" using dry ice, water, sand, cola and glass cleaner.

Unbeknownst to me one of my students made a video of the experience and put it on YouTube at

http://www.youtube.com/watch?v=1veYdeDxdJE

If I'd known, I would have had the photographer closer with his camera and microphone.

Is Experience the best teacher?

I've heard it said that "Experience is the best teacher" but maybe not. Maybe there's a better way to learn science. A classmate called for the adoption of a sexy new catchphrase for this different approach to teaching known as Scientific Inquiry. I agree, we ought to consider a ”cool slogan” that can be used to encompass the philosophy of Inquiry. Let’s look for a slogan that reflects the mystery of science but is broad enough to include the many facets of Scientific Inquiry.

Among other failures, it appears that we are not encouraging students to address their preconceptions nor are we nurturing the habit of thinking about thinking. My astronomy students just finished the “Reason for the Seasons” lab in which they first gave voice to their preconceptions, used measurements and reasoning to analyze the observations, and then revisited possible misconceptions.

Surprisingly, a significant number of my students accurately measured the apparent size of the Sun, organized the data, drew a graphic representation of the Earth’s orbit and still insisted that the Earth is closer to the Sun in the summer. We’ll need a slogan that embraces this reluctance to see the obvious.

Some of my students also wanted to know if their written descriptions of the observations were “right or wrong.” It appears that even in a university introductory astronomy course, we need to consider the pacing of student development of ideas about scientific knowledge. Let’s look for a slogan that reflects this experimental nature of science that’s so difficult for students to comprehend.

In TV shows such as CSI and MythBusters we see forensic experts and scientists solve mysteries using their qualitative understanding of nature. But not all of us are trying to solve mysteries. Many are just trying to survive day-to-day. Do members of the public really need a “qualitative understanding” of every concept? Maybe just knowing the right answers, the facts, the “quantitative relation” of scientific concepts, is enough for some people. Let’s find a slogan that embodies the mystery while acknowledging the mundane.

Students tend to think the purpose of controlled science experiments is to look for evidence that is consistent with their prior beliefs. While I’m not sure that’s a universally bad thing to do, we don’t really need to look far to find that same weakness in the practicing scientific community. Practicing scientists are also human too, and have all the strengths and weaknesses of that condition. We need a slogan that encapsulates this human tendency to see what we want to see.

Scientific Inquiry helps learners develop skills in collecting and analyzing evidence. It also encourages learners to address preconceptions. In addition, Scientific Inquiry guides the learners in think about thinking. A catchy slogan we might want to consider should probably address this multifaceted nature of Scientific Inquiry.

There are many ways to design a science course. Some teachers will need time and encouragement to learn more about Scientific Inquiry and think about science using this different approach.

Many children and adults assume that things are the way they appear and “science is about questioning the obvious.” Maybe we can get our slogan from a modern day version of a 19th century CSI. For Scientific Inquiry’s slogan I propose this phrase from the 2009 film “Sherlock Holmes” with Robert Downy Jr.:

“There’s nothing more elusive than an obvious fact.”

How do we know the Earth’s axis is tilted 23.5 degrees?

This is a question one of my astronomy students asked last week. That’s a perfectly good question, and I want to answer it using a different style than the one I’m use to.

Imagine you have observed that on one particular day the sun at its highest point in the sky (local noon) is actually low above the southern horizon. Some days later, you notice that the noon-sun is higher, 23.5 degrees higher in the sky than it was for your first observation. Again, days pass and you notice at noon that the sun is even higher than before, another 23.5 degrees higher!

What is making this happen? Why is the sun changing its position in our sky?

Some ideas might be mystical: maybe angels and demons are fighting over the sun, holding their own celestial rugby match.

Some ideas might be more material: maybe the Earth is wildly wobbling on its axis.

A radical idea may be that the Earth is tilted: maybe our rotational axis is not exactly perpendicular to the orbital plane of the earth around the sun.

Is there a test we can conduct to see if the Earth may be wildly wobbling on its axis? Since we’re studying celestial objects oft times we must wait for the universe to do the testing for us and we just observe. Over time we notice that the changes in the position of the sun in our sky happen slowly and consistently.

Around December 21, the noon-sun is the lowest that it’s going to get. Just 3 months later, around March 21, the noon-sun position is 23.5 degrees higher than it was in December. Another 3 months (June 21) and the noon-sun is another 23.5 degrees higher. Again, another 3 months and the noon-sun has returned to it’s mid-position. And then it repeats, over and over.

Researching astronomical records you find the same pattern described far into recorded history. Would these observations rule-out the hypothesis that the Earth is wildly wobbling? The regularity of year after year, century after century, would seem to tell us the movement is not wild.

You start noticing other aspects of the sky, both during the days and the nights. You may notice that the star called Polaris stays pretty much in the same spot of the sky, night after night, year after year. If you travel to the North Pole you may find that on June 21, the noon-sun stays 23.5 degrees above the horizon all day. Another 3 months later and the noon-Sun barely brightens the horizon. Then the North Pole sky is dark for 6 months, but eventually, on March 21, the sun begins to reappear.

Would those observations lead the discerning observer to the conclusion that the Earth’s axis is tilted 23.5 degrees? We didn’t disprove the angelic rugby match!

I’m reading Scientific Inquiry and Nature of Science, edited by L. B. Flick and N. G. Lederman, and I’m exploring this way of thinking about astronomy.

School Has Begun

The new semester at High Point University has begun, and I'm returning to teach a couple introductory courses in astronomy. I enjoy teaching there, and it affords me the opportunity to continue spreading the good news about astronomy.

On the first day of class I have the students pair off and interview one another. One question they consider is what they want to learn about astronomy during our time together.

Most of my students are second semester non-science-major freshmen. Some take the class just to earn a lab credit or a science credit. Very few have any background experience in astronomy.

Here's the breakdown of responses in my Tuesday class:
want to learn about stars: 6 responses
want to learn constellations: 4 responses
want to learn about planets: 2 responses
want to learn about the universe: 1 response
want to learn about black holes: 1 response
want to learn about astrology: 1 response
want to learn about 2012 and the end of the world: 1 response

Several responses were very general interest in science or astronomy, and some did not address this question at all.

The request to learn about 2012 actually spurred one other student into a recount of her research and her conclusion that the whole "end of the world" hype is just "stupid."

The planet formerly known as Red

Mostly I think Mars takes on a butterscotch hue, a touch of orangish rust floating on a background of ebony satin.

The fourth rock from the Sun has been rising earlier and earlier, making it a wonderful sight early at night.T here is was, rising in the East a couple nights ago them setting in the West when I went out early to get the paper the next morning.

Will humans ever get to Mars? Will I live long enough to see it happen?

There are so many obstacles to human presence on Mars. From political and economic here at home, to a lethal environment in the deep reaches of interplanetary space, we humans have quite a challenge facing us.

I rather hoped and believed we would have permanent outposts on the Moon by 2001, just the way Stanley Kubrick presented it back in the 60's. We haven't done too bad, though.

Our robotic explorers have visited many corners of our solar system and peered into far distances of the universe. We are receiving great pictures and wonderful clues from Mars from the rovers Spirit and Opportunity.

But the human presence is missing and that saddens me.

Preparing for Christmas Night Observing

Barbara warned me that guests to the observatory tonight may ask about the Christmas star. How do I plan to respond?

My first inclination was to attempt to debunk myths, but after reflection, that tactic seemed pointless.

From some quick research I learn that many Biblical scholars place the time of Jesus' birth in late 3 B.C.E., specifically between September 10th and September 25th. Some say the Magi were politicians from Persia, some say they were astrologers. If the Wise Men were believers in the influence of the relative positions of the planets on the celestial sphere, the star of Christmas may have been lees a sight in the sky and more a sign in their charts.

Modern planetarium software allows astronomers to "see" the sky years into the future and years into the past. During September of 3 B.C.E. then in February and again in May of 2 B.C.E. the King of the planets, Jupiter, moved past the bright star Regulus three times. Superior planets go thru retrograde motion because of the geometry of Earth's inner orbit and their outer orbits. After being hidden in the sunlight, Jupiter moved past Regulus, slowed, reversed direction and moved past Regulus again, then finally slowed, stopped and continued in its original direction among the background stars.

Blue-white Regulus is associated with royalty, and to have the King of planets wander past Regulus three times in less than a year could certainly be a noteworthy sight. Regulus is the brightest star in the constellation Leo, an important star group for the tribe of Judah in Israel.

On Christmas night 2009 Regulus will rise late in the evening. Jupiter will set early.

And now it has begun to rain. Forecasts call for the rain to continue thru the night.

Maybe next Christmas we can share the stories.