Cumberland-Times Sky Columns
April 2005

April 3 - The Lives of the Stars
April 10 - Astronomy Day
April 17 - Sky Guide Review
April 24 - FSU's Digital Portable Planetariu,

April 3 - The Lives of the Stars

Each week, pop magazines report on the love lives of celebrities, who is feuding/alienated with who, which star athlete is about to change teams for a sweeter deal, etc. What about the lives of the stars we see at night? The ancients regarded the stars as eternal, shining unchanged century after century.

This is almost correct. The reality is that stars are huge nuclear reactors with vast reserves of fuel that shine for millions or billions of years. How can we be sure that stars can shine that long?

We know the distances of the nearer stars by the motion of the Earth about the sun. (This causes a slight annual wiggle in their positions known as parallax. The parallax is very tiny, seen only by highly precise image measurements.) Star distances are in light years, the distance that light travels in one year, about 6 trillion miles. (A trillion is a million times a million.) Sirius, the night's brightest star now seen low in the southwest as it gets dark is 9 light years away, the nearest night star visible to the eye from this area.

From knowing the star distances and their brightness, we can compute the power of a star in watts. (Just as we gauge our light bulbs in watts.) Our sun's power is 4 followed by 26 zeroes watts! (This is 400 trillion trillion watts.)

We also know the masses (total amount of matter) of stars by their movement about other stars (in binary star systems). The brighter night stars have masses several times that of our sun.

By using Einstein's famed equation, E(energy) = M(mass)*C2 (C is the speed of light which is 300 million meters/second). Using this equation, we find that our sun consumes 4 million metric tons of matter every second. But our sun's mass is 2,000 trillion trillion metric tons! If the sun consumes only one tenth of its mass, then it can shine for about 10 billion years! Other stars have larger amounts of power and thus run down faster, say a few hundred million years! Thus the stars are ALMOST eternal, unlike our lives, our supply of coal, etc.

April 10 - Astronomy Day

Every mid spring, the Astronomical League (of Astronomy Clubs) selects a Saturday when the evening moon is about half full (called the first quarter phase). Then in many places across the U.S., Astronomy clubs set up telescopes for public viewing of the moon, planets, stars, etc. This Saturday, April 16th is the 2005 Astronomy Day.

The Cumberland Astronmy Club will have a new president following elections at our May meeting at the LaVale Public Library. The President-Elect is Steve Vincent of Grantsville, who has been a very active club member for several years. The Vice President will be decided at our May 15th meeting by a vote of the club members present. Continuing as our Secretary-Treasurer and League Representative will be Stephen Luzader of Frostburg, who has held that post for three years. (Previously Luzader was the treasurer and league representative.) Both Vincent and Luzader have been instrumental putting on a series of very popular star parties (public telescope observing sessions) at the Frostburg Recreational Complex that started in 2003.

Other active members of our local astronomy club include: Gus Johnson of Deep Creek Lake, a modest but very knowledgable amateur astronomer. Gus works at Garrett County State Parks where he gives frequent sky talks. Andy McCleary from Augusta is the club's traveler, who has seen astronomical sites around the world in Europe, South America and Asia. Another active member is Jay Williams of Bedford who recently travelled to Alaska to see the northern lights (didn't see them but saw a great fireball). Non travelers include this author, the outgoing Club President. Also from Grantsville are Jack and Pat Orner. Jack is one of the handiest club members, having built a mirror mount for binoculars.

Any one who sky gazes is in a sense a time traveler, for when you look at the stars, you are seeing most of them before you were born! Star lifetimes are typically millions or billions of years, so they are likely there as we see them. And when you view planets through a telescope, you are getting a view as if you have travelled millions of miles into space.

April 17 - Sky Guide Review

For the next few months, I will be reviewing beginner's astronomy books that are in in the Allegany County Library system. In that way, you can check out the book or request it if it's at another branch. These books may also be available in the Mineral County Library system or in Garrett County libraries. I will also mention some similar books that I have seen in local book stores. The reason why I will be adding this feature to my Cumberland Sky column is to promote reading both among our school students as well as their parents and other adults. Often the beginner's astronomy books for young people often are best books for interested adults who would like to become acquainted with the sky.

The National Geographic's "My first pocket guide to the Constellations" is a delightful starter book for younger readers. (A constellation is usually a recognized pattern of stars that covers a certain area of the night sky. Orion is a constellation.) One of the strengths of this pocket guide is that it only focuses on star groups, not providing an introduction to the key features of astronomy. When you are beginning a new field, you need to focus on one key area and become somewhat familiar with it. Then you can move onto another area, etc.

After a few pages of tips about star gazing, this book has evening star charts for each season, showing separate views looking North and looking South. In April you would look at the spring seaonal charts, which just show you the key star groups. You can write the group names down. The rest of the book is an alphabetical compilation of 2 pages per bright star group (29 altogether). There is a brief account of the constellation's origin, how to find it and how it appears to the eye, through binoculars and special objects for a telescope. Alongside the major map of each group are hand diagrams, giving you an idea of how big the constellation appears.

Comparable softcover books stocked in local book stores include "Peterson's First Guide to Astronomy" and the Golden Nature Guide, "Stars". These two books and the pocket guide are all under $10. But these last two books offer much more coverage of astronomy and may be harder to absorb than the pocket guide.

April 24th - FSU's Digital Portable Planetarium

Early this year, Frostburg State University purchased a portable digital planetarium projector and accompanying 19 foot wide inflatible dome. The digital projector (Alpha) is made by Digitalis Educational Solutions in Bremerton, Washington. Alpha uses a high quality fish eye lens to project a high resolution computer image onto the inside of the dome. Alpha shows all the bright and medium stars seen from your backyard (just like Starlab and our Projector at Frostburg State).

The planets and moon's positions are shown more accurately than either Starlab or our Tawes Hall projector. After selecting a planet, the moon or some interesting gas cloud, star cluster or galaxy, the Alpha projector can zoom towards that object, as if we could travel almost instantaneously through space. For instance, we can zoom at Saturn, revealing its rings and its giant moon Titan, in motion around it. The gas cloud below Orion's belt can be seen as a huge star forming region. Other interesting sights include the Ring Nebula, a smoke ring surrounding a burned out star. If we zoom onto M104, we see a spiral galaxy with its dusty central plane splitting it in two.

Besides the zoom features and stars, the Alpha projects a realistic day sky where the sun and planets nearby are shown. In this way, the sun's westward motion across the day sky can be shown dramatically. When the sun goes down, the stars begin to appear. All the constellations can be shown either as stick figures connecting the stars or with superimposed mythological artwork. The sun's path among the stars is shown as a red line. The compass directions along the horizon are marked with large glowing letters.

The University supported the purchase of Alpha and the 6 meter dome so it could bring the stars, planets and galaxies to camps and community centers so many more could get acquainted with the sky. This month, I took Alpha and the 6 meter dome to four schools. I would like to continue to tour with Alpha and its dome. Since Alpha and dome take about 45 minutes to set up and an equal amount of time to stow away, a total audience of 40 is required.(The 40 minimum could be the total attendance of 2 separate showings.) The presentation described above would last typically 30 minutes. The Alpha programs would be live, allowing audience questions and comments. There is no fee for an Alpha visit, aside from a modest allowance for car mileage. Call me at (301) 687-4270 and press 4 to leave your request for Alpha. I'll get back to you in a few days.