Paul Derrick's Stargazer



2001 Stargazer Columns

 Copyright by Paul Derrick.  Permission is granted for free electronic distribution as long as this paragraph 
 is included.  For permission to publish in any other form, please contact the author at

Dec. 22, 2001: Johannes Kepler: Thinking Outside the Box
Dec. 08, 2001: Saturnalia
Nov. 24, 2001: Are You an Ophiuchus?
Nov. 10, 2001: Here Come the Leonid Meteors
Oct. 27, 2001: Mercury and Venus in the Morning Sky
Oct. 13, 2001: Halley's Comet and the Orionid Meteor Shower
Sep. 29, 2001: The Ecliptic at Different Altitudes
Sep. 15, 2001: The Moon This Fortnight
Sep. 01, 2001: Venus and the Beehive Cluster
Aug. 18, 2001: Seeing the Southern Lights
Aug. 04, 2001: A Class, a Meteor Shower and a Star Party
Jul. 21, 2001: The Summer Sky
Jul. 07, 2001: Morning Planetary Show
Jun. 23, 2001: Mars in Retrograde Motion
Jun. 09, 2001: Southern Hemisphere Stargazing Is Different in Many Ways
May 26, 2001: Here Comes Mars
May 12, 2001: First Views of the Southern Sky
Apr. 28, 2001: Stargazing in New Zealand
Apr. 14, 2001: A New Central Texas Observatory
Mar. 31, 2001: Seeing the Southern Sky
Mar. 17, 2001: Saying Goodbye to Venus
Mar. 03, 2001: Pleiades
Feb. 17, 2001: The Winter Sky
Feb. 03, 2001: Transparency and Seeing
Jan. 20, 2001: The Moon Visits 4 Planets
Jan. 06, 2001: The Night Sky in 2001

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December 22, 2001, 2001

Johannes Kepler: Thinking Outside the Box

Scientific and theological thought for well over a millennium was -- using the currently vogue "thinking outside the box" metaphor -- solidly locked within a box constructed by Ptolemy of Alexandria about A.D. 140. In his book, The Almagest, a compilation of astronomical knowledge of the time, Ptolemy placed the Earth at the center of everything.

Early Christian theologians embraced and framed their understandings of God and humanity around this view. They even added the idea that the Earth-centered cosmos is perfect, an idea which came to be incorporated into scientific thinking.

It was from within this scientific and theological thought box that four men -- Nicholas Copernicus (1473-1543), Tycho Brahe (1546-1601), Galileo Galilei (1564-1642) and Johannes Kepler (1571-1630) -- radically changed how we view the world and our place in it. Mostly working independently of each other, they removed us and our planet from the center of the cosmos.

Copernicus began with his Sun-centered theory. But ironically, while he and the others played key roles in moving us to a more accurate view of our cosmos, even they had difficulties breaking out of the prevailing thought box.

Copernicus' Sun-centered theory had a serious deficiency which worked against its acceptance. Buying into the theological box, he assumed that because the cosmos is perfect, the orbits of the planets must be perfect circles. Because of this assumption, his predictions of planetary motion were no more accurate than those based on Ptolemy's Earth-centered theory.

Even the great mind of Galileo couldn't completely escape the prevailing thought box. While his telescopic investigations produced evidence strongly supportive of Copernicus' theory, he also remained locked tightly in the perfect-circle box.

Tycho Brahe was one of astronomy's greatest pre-telescope observers. His keen observations and meticulous records of the movements of Mars played a crucial role in the Copernican revolution, yet he could never break out of the old Earth- centered idea box and died clinging to that view.

Johannes Kepler embraced the Sun-centered theory at an early age. But for years he tried to make Copernicus' theory, with perfectly circular orbits, fit Tycho's observations, but to no avail. In a classic case of thinking outside the box, he got an insight: perhaps orbits are not circular but elliptical. Eureka! Finally, theory and observation were reconciled and our understanding of our cosmos took a quantum leap.

Dec. 27 is the 430th anniversary of Kepler's birth.

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December 8, 2001


This is the time of year when three world religions observe holidays: Islam's Ramadan, Judaism's Hanukkah and Christianity's Christmas.

Before the creation of these holidays, Romans celebrated the Feast of Saturnalia honoring one of their major gods, Saturn. An offspring of Gaea (mother earth) and Uranus (father sky), Saturn is the father of Jupiter (king of the gods), Neptune (god of the seas) and Pluto (god of the underworld).

Since Saturn was regarded as the Roman god of agricultural abundance, Saturnalia was originally a thanksgiving celebration. In time it lost its agricultural significance and became a popular 7-day holiday period of merriment marked by feasting, visiting and gift-giving from December 17-23.

According to Dr. Daniel Harmon, University of Washington professor of classics, during Saturnalia "schools and businesses closed, no criminals could be punished, armies could not start wars, and slaves and masters became temporary equals." Most rules of public conduct were suspended and overindulgence was the order of the day. Dr. Harmon and others point to Saturnalia's likely influences on modern Christmas celebrations.

With Saturnalia less than two weeks away, it seems fitting that the planet Saturn is prominent in our evening sky this year. Currently rising just before sunset, the ringed planet is seen in the constellation Taurus the Bull. Throughout most of December, it will be about 4 degrees to the left of Taurus' brightest star, Aldebaran, the red eye of the bull.

To find Saturn, look due east around 8 p.m. for the brightest star-like object 36 degrees above the horizon, above the rising Orion. Saturn is slightly brighter than Aldebaran and appears creamy-colored compared to the star's reddish tint. Don't confuse Saturn with the bright star Capella 30 degrees to Saturn's left or with brilliant Jupiter rising in the same area around 7 p.m. (The width of your fist held at arm's length is 10 degrees; the width of your index finger is 1 degree.)

When you spot Saturn, be sure and say: "Happy Saturnalia."

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November 24, 2001

Are You an Ophiuchus?

How many times have you been asked, "What's your sign?" You know, of course, the inquirer means your astrological sign. Although scientific research has demonstrated astrology's lack of credibility, this pseudoscience has a substantial following.

Most newspapers carry daily horoscopes, yet few provide daily astronomical information beyond times of the rising and setting of the Sun and Moon. And most bookstores seem to stock far more astrological than astronomical titles.

In astrology, your sign derives from the constellation the Sun was "in" when you were born. Since this supposedly has significance in shaping your personality and fate, it should be important to have correct information about your actual sign. Yet the dates used in horoscopes are so far off from reality that most people were not born under the sign they are led to believe.

Using my August 27 birthdate as an example, those of us born between August 23 and September 22 are supposed to have been born under the sign of Virgo. Yet the Sun was actually in Leo from August 10 to September 16, thus my sign should be Leo.

So what accounts for these date discrepancies? As Earth makes its annual journey around the Sun, the Sun appears to "move through" the background constellations -- the 12 signs of the astrological zodiac. (One wonders why the Sun was used since we can never see the constellation it's in due to sunlight.)

Astrological signs were affixed long ago and are based on locations of the Sun at that time. However the Earth undergoes a 26,000-year wobble, called precession, which gradually shifts its orientation to the stars, and the Sun's path against them.

This shift has not only changed the dates the Sun enters and leaves constellations, but has changed the constellations through which the Sun passes. It now moves through 13 constellations, the additional one being Ophiuchus, the Serpent Bearer.

According to astrology, the Sun is in Scorpius from Oct. 24 to Nov. 22, and then in Sagittarius Nov. 23 through Dec. 21. In fact, the Sun is in Scorpius only briefly (Nov. 23-28) after which it moves, not into Sagittarius, but Ophiuchus where it stays until Dec. 17. So if your birthdate is between Nov. 29 and Dec. 17, you can have some fun with friends who ask about your sign. Tell them you're an Ophiuchus, and let them try to find that in their horoscopes.

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November 10, 2001

Here Come the Leonid Meteors

Once again, the experts say this could be a banner year for the annual Leonid meteor shower which peaks next weekend. Several factors give hope for an unusually good display.

More good news: part of the shower is predicted to peak when North America is well positioned to see it. The Leonids derive from debris left by comet Tempel-Tuttle which visits the inner solar system every 33 years. As Earth passes through the comet's orbital path, pieces of debris burn up at altitudes of 40-70 miles up in our atmosphere, producing meteors. Tempel-Tuttle last came by in February 1998, depositing a fresh supply of debris in its wake. Thus the past few Novembers have seen a significant increase in activity from the usually modest Leonids.

One bit of bad news -- and it's minor -- is that the best show is likely to come when most of us are normally fast asleep. Meteor forecasters expect Earth to pass through a rich stream of debris between 4-5 a.m. (Waco time) the morning of Nov. 18.

While some astronomical predictions, like lunar and solar eclipses, are extremely accurate, meteor prognostication is inexact as best. There's the possibility that the shower will fail to produce the anticipated abundant display. And since time predictions are educated "guesstimates," the serious observer should be on watch all night, starting around midnight when Leo, the constellation from which the meteors seem to emanate, rises in the east.

If staying up all night isn't your cup of tea, you might consider doing what I'll probably do -- go to bed a little earlier than usual, get up and view from about 3-6 a.m., then go back to bed for another couple of hours of sleep before church.

There could be increased meteor activity a night or two before and after Nov. 18, so if you're out, keep an eye skyward. And you'll see more meteors under darker skies, so if you can do your meteor watching from beyond urban light pollution.

According to Guy Ottewell's 2001 Astronomical Calendar, "Leonids approach Earth virtually head-on, are extremely swift, often bright, and 50-70% leave persistent trains." By 4 a.m., Leo will be high in the southeast. But since meteors will likely be seen in all parts of the sky, just bundle up, lie back and keep looking upward. A thermos of coffee might also be nice.

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October 27, 2001

Mercury and Venus in the Morning Sky

The upcoming fortnight provides excellent opportunities for early risers to see the elusive planet Mercury. Being nearest the Sun, Mercury never appears far from our star, being visible only near the western horizon shortly after sunset or the eastern horizon before sunrise. While it shines brightly -- brighter than most stars -- it's still a challenge to find since it's always low and seen when the sky is not fully dark.

Monday morning Mercury is at greatest elongation west of the rising Sun, that is, at its maximum distance from the Sun as seen from Earth during this apparition. But the best news is it will have a "guide star" to help you find it. The blazing Venus, currently the "morning star," will be within one degree of Mercury from now until Nov. 7. (The width of your index finger held at arm's length is about one degree.)

Look for them 30-45 minutes before sunrise low in the east, with Mercury left of and slightly lower than Venus. The sooner you look during the next two weeks the better as both are gradually sinking into the Sun.

* * * * * * *

Next week's full Moon might create some confusion. Does it fall on Oct. 31 or Nov. 1, and is it the Hunter's Moon or a Blue Moon? The answer is "all of the above," depending on where you live.

The Moon is full the exact moment it and the Sun are on opposite sides of Earth. Most calendars show this full Moon falling on Thursday, Nov. 1, yet in the Central Time Zone and points west it will be Wednesday, Oct. 31.

This apparent discrepancy arises from the fact that the moment of fullness comes Wednesday at 11:42 p.m. in our time zone but after midnight in the Eastern Time Zone where it will already be Thursday. (To avoid confusion, astronomers usually use Universal Time, formerly known as Greenwich Mean Time, rather than local time. So officially the full Moon occurs Nov. 1 at 5:42 UT.)

Being the first full Moon after the Harvest Moon, this is the Hunter's Moon. But as our second full Moon this month, it is also called a Blue Moon here and further west. For the Eastern Time Zone and further east, however, two full Moons will occur next month, making the Nov. 30 full Moon their Blue Moon.

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October 13, 2001

Halley's Comet and the Orionid Meteor Shower

Perhaps you saw the famous Halley's Comet when it last passed in 1986. For me, seeing it was a thrill as I had awaited its return more than 30 years, having first heard about it in 1954.

Comets, described by astronomer Fred L. Whipple in 1951 as "dirty snowballs," are huge (several miles wide) chunks of solar system debris which orbit the Sun. Most spent their entire lives far beyond the farthest planets in a realm called the Oort Cloud. At this distance they are virtually undetectable and certainly not visible from Earth. A few, however, leave the Oort Cloud, wander into the inner solar system and become observable.

When we see comets, we don't actually see their solid dirty snowball nucleus--it's much too small. Even the Hubble Space Telescope can't see mountain-sized objects millions of miles away. What we see is a comet's huge coma and tail consisting of material "melted" off the nucleus when it gets close enough to feel the Sun's heat. This material--mostly dust-size particles, water vapor and gasses--becomes visible by reflecting sunlight, similar to what we see when we view a cloud or smoke in our sky.

Unlike planets which orbit the Sun in nearly circular orbits, comets orbit in highly elliptical paths. Halley's Comet, with a 76-year orbital period, travels as far from the Sun as Neptune and as near as Venus.

As a comet travels along it leaves a trail of ejected and melted debris strewn along its way. By chance, the paths of some comets cross the path of Earth as it orbits the Sun. When Earth crosses a comet's path, it passes through it's debris. As these tiny pieces of cometary material enter Earth's atmosphere, they burn up producing what we see as meteors (also called "shooting stars" and "falling stars").

Every May and October, as we pass through the orbital path of Halley's Comet, we see brief increases in meteor activity called meteor showers. The May shower is called the Eta Aquarid shower while the one in October is the Orionid meteor shower. (The names derive, not from the parent comet, but from the constellation out of which the meteors seem to come.)

If you missed seeing Halley's Comet in 1986, and don't want to wait until its next visit in 2061 to see it, don't fret. You can at least see pieces of it during the Orionid meteor shower which peaks next weekend. Oct. 20 and 21, begin watching an hour or so before midnight, after the Moon sets. The longer you stay up the better as meteors are most abundant between midnight and dawn. No special equipment is needed. Just lay back facing eastward and look for remnants of Halley's Comet streaking across the sky.

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September 29, 2001

The Ecliptic at Different Altitudes

Last summer the Stargazer got an email from Ted Symank with a question about the ecliptic and its altitude (height) above the horizon. He wrote, "After I took a science class at Baylor, I could look up into the night sky and see the plane of the ecliptic...when Jupiter, Saturn and Venus would roll by. But now with Mars in the sky its...path seems low. Am I seeing things?"

The ecliptic, referred to by Ted, is the path of the Sun, Moon and planets through our sky as they seem to circle the Earth. (Of course, thanks to Copernicus, Galileo and others, we know the Earth and other planets really circle the Sun; only the Moon circles the Earth.) More precisely, the ecliptic is the apparent path of the Sun. The planets travel fairly closely along this path because they all orbit the Sun on about the same plane, and the Moon likewise orbits Earth on this plane.

Ted's observation is astute as the ecliptic does indeed appear at different altitudes. At times the planets arc higher above the horizon than at other times, as do the Sun and Moon. Last winter, when Jupiter and Saturn were prominent in the evening, they reached some 80 degrees above the horizon. However by summer when Mars was prominent in the evening, it reached an altitude of only 32 degrees. Yet they all follow essentially the same path along the ecliptic.

Perhaps like most folks, you've never noticed this difference. But you've likely observed that the summer Sun gets higher than the winter Sun.

The ecliptic's altitude varies with both the season and the time of day (or night). This difference comes from the fact that the Earth's axis is tilted 23 1/2 degrees from the plane of its orbit. (That tilt, by the way, is also responsible for our seasons, but that's another column.)

During the summer, with our hemisphere tilted toward the Sun, the ecliptic (and Sun) appears higher during the day. From Waco's latitude, the noontime Sun climbs 82 degrees above our horizon the first day of summer. During summer nights, however, the ecliptic dips much lower with the planets and Moon rising no more than 30 to 40 degrees in altitude. The situation is reversed during the winter when our hemisphere is tilted away from the Sun. On the first day of winter, the noontime Sun reaches only 35 degrees above our horizon whereas at night the planets and Moon can climb to more than 80 degrees.

At the beginning of fall and spring, the ecliptic's altitude is the same at noon and at midnight, with the noontime Sun reaching 59 degrees above the horizon. But in the fall, the ecliptic is low in the early evening and high in the early morning, and the opposite in the spring. Now, just a few days into fall, the noontime Sun reaches nearly 60 degrees above the horizon, Mars is seen low in the south soon after sunset, and Jupiter and Saturn are high at dawn.

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September 15, 2001

The Moon This Fortnight

During this upcoming fortnight, the Moon will be the night sky object of note -- starting today. If you're out before dawn this morning, look for a thin crescent Moon near Venus and Leo's Regulus low in the east.

After the Moon is new Monday, it will then move into the evening sky. Tuesday evening soon after sunset, a tiny crescent Moon will be just to the right of the planet Mercury and Virgo's brightest star, Spica, low in the west. Seeing this will require an unobstructed view of the western horizon, and binoculars will help. About 8 p.m., as twilight settles over the sky, pan 5 degrees above the horizon, just south (left) of due west. (The width of your fist held at arm's length is about 10 degrees; the field of view of most 7x50 binoculars is around 6 to 8 degrees.)

The next evening the Moon will be easier to see as it will be slightly larger and higher above the horizon. It will then be a little above the planet and star which will still be just above the horizon and will still need binoculars to see. Mercury and Spica will be less than 1 degree apart Thursday.

The evening of Sept. 22, a larger crescent Moon will be above Scorpius' brightest star, Antares. Two evening later, on Sept. 24, it will reach 1st quarter as it passes above Mars.

As those who live (or have lived) near coastal areas are aware, twice each day Earth's oceans, seas, gulfs, bays and other open waters experience high and low tides. This effect is produced by the Moon's gravitational attraction on Earth's surface water as our planet makes its daily rotation. (Closed bodies of water like lakes and ponds do not experience tides.)

Tomorrow the Moon is at perigee, the point in its elliptical orbit when it comes nearest to Earth each month. Tidal activity is more pronounced around perigee as the force of gravity between two objects is greater the nearer the objects are to each other.

This month, perigee happens to occur one day before Monday's new Moon, thus coastal areas can expect even higher-than-average high tides. The Moon is new when it passes between the Sun and Earth, producing an alignment of the three bodies. With the Sun and Moon aligned on the same side of Earth, their gravity pulls in the same direction with combined force. Thus Earth's open waters will be pulled even more than usual. But surprisingly, although the Sun is vastly larger and more massive, our little Moon has a far greater effect on tides as it is 400 times closer.

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September 1, 2001

Venus and the Beehive Cluster

Tomorrow morning, shortly before the break of dawn, the brilliant "morning star," Venus, will pass near the Beehive star cluster. Finding the Beehive can be challenging, so the proximity of Venus will be helpful. The optimum viewing time will be 5:30 - 5:45 a.m. -- just before dawn breaks and with the full Moon setting in the west.

The brightest object in the area, Venus will be nearly 15 degrees above the eastern horizon. (The width of your fist held at arm's length is about 10 degrees.) The much fainter Beehive will be one and one-half degrees to the upper left of Venus -- a little more than the width of your index finger held at arm's length.

The Beehive star cluster is located in the constellation of Cancer, the Crab. Under dark skies, naked-eye views show the Beehive as a soft cloudy patch of light about the size of the full Moon. Binoculars, however, show it for what it really is -- a lovely cluster of many individual stars. At a distance of 515 light years, it is one our nearer neighboring star clusters.

The Beehive (also known as Praesepe, the Manger, NGC 2632 and M44) has been known since antiquity. Until the invention of the telescope, it was believed to be a nebula of cosmic clouds. A pair of binoculars, however, reveals dozens of individual stars, and telescopes show over 200 stars. In cosmic terms, the Beehive is young. Its stars are believed to be only 400 million years old, compared with our Sun, for example, which formed 5 billion years ago.

Venus has been the "morning star" since spring and will remain in the morning sky throughout most of the rest of 2001. Shining at a brightness of magnitude -4.3, Venus is brighter than any star or other planet, and is outshone only by the Moon and Sun.

While you're out, be sure to look for Jupiter and Saturn. Jupiter is nearly 30 degrees above Venus in the constellation Gemini. It is the second brightest object in the area at magnitude -2.1. Saturn is 25 degrees above Jupiter in the constellation Taurus, just 6 degrees to the lower left of the bright star, Aldebaran, and the Hyades star cluster. Currently shining at magnitude 0.7, Saturn's brightness is virtually equal to Aldebaran's magnitude of 0.9. (Notice that the magnitude scale, a measure of the brightness of night-sky objects, is reversed -- the lower the number, the brighter the object.)

Finally, to the right of Jupiter and Saturn is the great giant of the winter sky, Orion. He's still sleepily lying on his side, but beginning to awaken for his 2001-2002 season.

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August 18, 2001

Seeing the Southern Lights

During our spring visit to New Zealand, we were treated to a sight rarely seen from Texas -- the aurora, those beautiful, eerie-looking sheets of colored light in the night sky. In the southern hemisphere they are the aurora australis ("southern lights"), like our aurora borealis ("northern lights"). Whether north or south, they are an awesome sight.

Late one night, after an afternoon excursion to a remote light house followed by a late dinner, we were returning to our hostel some distance away. As we drove across the highest point of a small mountain range -- an elevation of some 1,000 meters and far from any major city lights -- I prevailed upon my wife and traveling companions to stop for some brief stargazing.

To our amazement and delight, we saw much more than the beautiful southern sky as a huge area was ablaze in brilliant red. The colorful glow extended from the horizon to high in the sky, and spanned nearly a fourth of the way around the horizon. Many brighter stars were clearly visible through the aurora. We saw no other colors -- such as the greens reported by some -- however we did see ghostly whitish streamers streaking upward.

Upon returning to our hostel an hour later, the aurora was still visible but not as brilliant. Either it was starting to fade, or was being diminished by the lights of the small town of Motueka. Of all the incredible sights I saw on our wonderful New Zealand trip, none exceeded this unexpected delight.

Auroras are usually seen only from far-southern (and far- northern) latitudes, near the Earth's magnetic poles. The beautiful sheets of often different colored lights are produced when charged particles from the Sun energize molecules a hundred or more miles up in our atmosphere, causing them to glow. While auroral displays are common in Earth's polar regions, they are rarer in the middle latitudes of New Zealand, and Texas.

Upon returning home, I read that while we were seeing the southern lights from New Zealand, west Texans were seeing the northern lights from the Ft. Davis area. For decades scientists have been aware of an 11 year cycle of sunspot activity which produces huge magnetic storms. During these periods auroras are more likely to be seen at lower-than-usual latitudes.

Having lived my entire life in Texas, this was only the second time I had seen the aurora. In March 1989 -- during the last 11-year solar cycle peak -- the northern lights were briefly visible from Waco. By good fortune, I was working outside and caught the surprising display. Perhaps you did too.

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August 4, 2001

A Class, a Meteor Shower and a Star Party

Today's column tells of three upcoming "audience participation" events you may want to put on your calendar: a class, a meteor shower and a star party.

Stars and Constellations Class. The Stargazer's five-session Stars and Constellations of Summer class will be held 8:45 - 10 p.m. August 6, 7, 8, 9 and 13. The class, for novice stargazers, requires no prior knowledge or equipment. The first session, held indoors, covers stargazing basics. The four "under-the-stars" sessions are at Camp Fire's Camp Val Verde, a few miles west of Waco. The course helps students learn the summer's major constellations and bright stars using sky stories -- some from antiquity, some Stargazer originals. The fee is $25 per person with discounts for families; all ages are welcome. (Some free scholarships are available.) Clouded out sessions are made up at later dates. For information or to register, call or email the Stargazer (see number/address below).

Perseid Meteor Shower. Once again, it's time for the Perseid Meteor Shower, usually one of the best showers each year. Although this year's display will be partly washed out by a bright Moon, it should still it will worth a look. The best viewing will likely come the late evenings of Aug. 11 and 12 until the Moon rises an hour or so after midnight. Perseus, the constellation from which the meteors seem to emanate, rises in the northeast around midnight. No special equipment is needed for viewing meteors -- just lay back and look up in a generally eastward direction, preferably away from city lights.

Lake Whitney Star Party. There will be a free, public star party Saturday, August 18, at Lake Whitney State Park. Afternoon events include telescope making and testing demonstrations and video programs. At 8:30 p.m., I will present a slide program, "The Sky Down Under" on my recent visit to New Zealand, followed by Ed Flaspoehler's "Summer Objects," a slide program highlighting constellations and other objects visible in the summer evening sky. After dark there will be an outdoor guided tour of the night sky and telescope viewing. All events are free except for the park's nominal entrance fee. For more information, contact the event organizer, Thomas Williamson at

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July 21, 2001

The Summer Sky

Many stargazers regard the evening sky of summer as their favorite of the year. In part it has to do with the season itself as temperatures after sunset generally become pleasant, unlike chilly winter nights which often require cumbersome bundling. A downside is that summer's late sunsets and early sunrises make for shorter and less convenient view times.

While each season has beauties of its own, the summer's array is hard to top. Our home galaxy, the magnificent Milky Way, stretches from the southern to northern horizon, tilting to the east and dividing the sky into two unequal parts. Although the Milky Way is visible virtually all year, the sections displayed in the summer -- when viewed from dark skies -- are the richest seen from the northern hemisphere.

The galaxy's center, and brightest appearing part, is seen toward the south running through Scorpius and Sagittarius. One of the few constellations to resemble its namesake, Scorpius actually looks like a scorpion. Sagittarius, the archer, located to the left (east) of Scorpius, looks more like a teapot than a centaur (half man, half horse) with a bow and arrow. This area is also currently hosting the bright reddish planet Mars.

Further along the Milky Way and high in the east are three bright stars forming the Milky Way Triangle (also known as the Summer Triangle). The brightest and highest, Vega, is the brightest star in the small constellation Lyra, the musical lyre. Vega lies just beyond the western edge of the Milky Way.

Thirty-four degrees to Vega's lower right is Altair in Aquila, the eagle. (The width of your fist at arm's length is 10 degrees.) Altair is across the Milky Way from Vega, on the eastern edge.

Twenty-four degrees to Vega's lower left is Deneb in Cygnus, the swan. The swan appears to be flying from north to south along and within the Milky Way. Deneb is the swan's tail star. Cygnus is informally known as the Northern Cross with Deneb at the cross' top.

The Milky Way disappears into the northern horizon after running through Cepheus, the king, and Cassiopeia, the queen.

If you live in a light-polluted town, travel a few miles and treat yourself to some dark-sky views of the summer sky. And take your kids, or your neighbor's kids -- you won't be sorry.

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July 7, 2001

Morning Planetary Show

Mars has been putting on quite a show these past few weeks. Being at its closest to Earth in several years, it appears brighter and larger than usual, outshining everything except the Moon. But it's a one-man planetary show as there are no other planets in the evening sky.

If you're a regular up-and-out-before-dawn early bird, perhaps you already know why. The rest of the naked-eye planetary cast is putting on a remarkable show in the morning sky. Looking low in the east northeast about 45 minutes before sunrise, one can see Venus, Saturn, Jupiter and Mercury grouped in one area.

But simply seeing them is just part of their show. The real entertainment will come in watching them over the next week as they are paired off like two dancing couples.

Venus, by far the brightest of the four, is now 5 degrees above Saturn. (The width of your fist held at arm's length is 10 degrees.) Saturn is 4 degrees to the upper left of Taurus' bright reddish star, Aldebaran. Over the next week, Venus will dive down between the nearly equally-bright Saturn and Aldebaran, passing within 1 degree (2 moon-widths) of Saturn on July 15. Nearer the horizon, the elusive Mercury is now 4 degrees to the upper right of the brighter Jupiter. The fast moving Mercury will pass within 2 degrees of Jupiter Friday.

Even the Moon gets into the show when a crescent Moon passes the Venus-Saturn duo July 17, and the Jupiter-Mercury pair July 19. As if trying to steal the planets' limelight, the Moon occults (passes in front of) Venus the afternoon of July 17 but binoculars or a telescope will be needed to see that show.

After next week, Mercury leaves Jupiter and sinks into the Sun while Venus, after passing by Saturn, heads toward Jupiter for an early August rendezvous.

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June 23, 2001

Mars in Retrograde Motion

Hopefully you've been watching Mars, the brightest star-like object in the evening sky. Have you noticed that it now seems to be moving backward in the sky from night to night?

In the course of a night, the stars, Moon and planets appear to move east-to-west across the sky, like the Sun during the day. This apparent movement has nothing to do with their actual motion, but is caused by the Earth's west-to-east rotation.

But the planets do move as they travel around the Sun, and their movement can be seen against the background stars. The movement of the more distant planets like Jupiter and Saturn is slower and usually noted over weeks or months. The movement of the planets nearer the Sun like Mars is faster and can be observed from night to night.

All the planets orbit the Sun in the same direction, and as viewed from Earth move west to east against the background stars -- at least, most of the time. But there are times when they seem to reverse direction and move backward, or east to west. After a while, they then again reverse direction and resume their west to east movement, called direct motion.

This apparent reversal, called retrograde motion, baffled early astronomers who thought the planets actually had periodic backward motions. It is now understood that this is an optical illusion. Being nearer the Sun Earth travels around the Sun faster than the outer planets. When it passes between the Sun and one of these more slowly moving planets, the passed planet seems to temporarily reverse course and move backward.

The diagram, showing lines of sight between Earth and Mars at 7 different times, can help visualize this. In late February (time 1), Mars was approaching Scorpius' brightest star, Antares, from the west. It passed near Antares in early March (time 2). By early May, Mars was near the nebulous star cluster called M8. May 11 (time 3), it began its retrograde motion, heading back toward Antares. June 13 (time 4), Mars reached opposition where Earth and Mars are aligned with the Sun. By July 19 (time 5), Mars will be back near Antares, but before reaching the star will resume direct, west-to-east motion. Early September (time 6), it will be back near M8, and by mid September (time 7), well east of M8 on its eastward journey.

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June 9, 2001

Southern Hemisphere Stargazing Is Different in Many Ways

As reported in previous columns, I recently traveled to New Zealand, deep in the southern hemisphere. I knew viewing the night sky from below the equator would be different, but it was even stranger than I had anticipated.

Parts of the night sky can be seen only from the southern hemisphere, so I knew I would see regions I'd never seen. Still actually viewing them for the first time made me feel like an alien on a planet in a different part of the galaxy. While the TYPES of objects I saw were familiar -- stars, constellations, clusters, nebulae, distant galaxies, even the Milky Way -- the specific objects themselves were quite unfamiliar.

This unearthly feeling was also elicited by New Zealand's birds, trees and flowers. Many were new and exotic, like specimens from a different planet.

But it wasn't just new things that made stargazing different. The sky is topsy-turvy "down under." Even familiar constellations were hard to recognize when seen up-side-down and backward from what I'm used to. It was eerie and disorienting to see Orion the Hunter with his sword "hanging" upward from his belt, and to find Taurus the Bull to Orion's lower left where Orion's big dog, Canis Major, is supposed to be.

Seeing familiar constellations in "wrong" places adds to the disorientation. In the U.S., for example, we see Scorpius the Scorpion fairly low in the south in the summer, not high overhead (and up-side-down and backward).

There are 21 especially bright stars called 1st-magnitude stars. At any one time, we usually see no more than 8 to 10. In New Zealand, 13 to 15 of these bright stars are visible virtually every night -- more than we can ever see at one time from Texas.

The Sun, Moon and planets move across our sky along a path called the ecliptic. This path doesn't go straight overhead but tilts. From the our hemisphere, it tilts to the south, so as the Sun moves east-to-west across our daytime sky, it appears to move left-to-right. In the southern hemisphere, the ecliptic tilts north, making the Sun seem to move "backwards," or right-to-left. When using the Sun to judge the approximate time of day -- like mid-morning, early afternoon, late afternoon -- I frequently found myself confused by the backward-moving Sun being in the "wrong" place.

The Moon, planets and stars also seem to move backward across the night sky, creating a similar nighttime confusion.

Seeing that there is no "south star" comparable to our North Star, I wondered if New Zealand Boy and Girl Scouts have trouble finding their way in the woods. And the south magnetic pole is considerably off from the true south pole, making the use of a compass complicated.

Just when I thought I was getting the hang of the southern sky thing, the full Moon threw me for one final loop. It's also up-side-down, making the old "man in the Moon" unrecognizable.

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May 26, 2001

Here Comes Mars

If you've recently been outside in the late evening, maybe you've noticed a very bright object in the east. That's our neighboring planet, Mars. Over the next few weeks as Earth and Mars pass relatively close to one another, the Red Planet will dominate our evening sky, outshining everything but the Moon.

Tonight Mars rises shortly after 10 p.m. It will rise earlier each night, and by mid-June will come up around 8:30 p.m.

Earth makes one trip around the Sun every 365 1/4 days in what we call a year. Mars, being farther from the Sun, has a longer journey and takes nearly 2 Earth-years. The result is that every 2-plus years Earth passes Mars, bringing the two planets into alignment with the Sun (called opposition) and closer to one another than usual. This presents a great time for observing Mars as it appears bigger and brighter.

But even all oppositions aren't the same. Both Earth's and Mars' orbits are elliptical rather than circular, so sometime they are nearer the Sun, and sometime further away. Thus the distance between them at opposition can vary from as much as 64 million miles to as few as 34 million. Next month we will pass within 41 million miles -- the closest we've been since 1988.

Mars reaches opposition June 13, and the two planets will be closest June 21. But it's not too early to start observing now. To naked eyes and in smaller binoculars, Mars looks like a bright reddish star-like point of light. Small telescopes and even higher-power (10x or greater) binoculars can show it as a tiny sphere. Moderate to larger telescopes begin to reveal some of the planet's features. You might see a small whitish polar cap at the top or bottom edge, and darker surface areas may be visible on the planet's face.

Some advanced observing tips for telescopic observers: orange and yellow filters accentuate surface features while blue filters show clouds and atmospheric features. For more information, see Daniel M. Troiani's article in the May 2001 issue of *Sky & Telescope* (pg. 102ff).

Mars will remain in our evening sky until next spring. After June, however, it will become gradually more distant, and will appear increasingly smaller and less bright. So enjoy it while you can as it won't be this bright again until 2003.

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May 12, 2001

First Views of the Southern Sky

In the last column, I told of our recent visit to New Zealand and how I discovered a surprisingly beautiful country with remarkably friendly people. I also confessed that my real interest in the visit was the country's location in the southern hemisphere where I could see the southern sky for the first time.

The night sky is such that far-northern parts are visible only from the northern hemisphere and far-southern parts only from the southern. For example, New Zealanders never see our familiar Big and Little Dippers or the North Star. Having never traveled further south than Texas' Rio Grande Valley, there are parts of the night sky I'd only read about and longed to see. So I looked forward to this trip with great anticipation.

After a 12-hour nonstop flight, we arrived in Auckland just before dawn. My first view of the southern sky from the light- polluted airport merely whetted my appetite. High over head I could just make out Scorpius and Mars. Dawn was beginning to lighten up the sky and I was completely disoriented, so I recognized nothing else. We then flew on to Christchurch.

To my dismay, the first night was cloudy. The next night, however, following dinner at the home of some nice "Kiwis" (as New Zealanders call themselves in reference to the kiwi bird found only in NZ), I excused myself and went out to check the sky which had been cloudy all day. To my amazement, it was crystal clear. Even from within Christchurch, I immediately saw Orion -- but up-side-down from what I'm used to seeing. Turning around, I got my first view of the Southern Cross and the bright stars, Alpha and Beta Centauri. Over the next half hour, we (having been joined by my wife and friends) could make out the southern Milky Way and some other inhabitants of the southern sky. I was thrilled but even more anxious to view from truly dark skies.

That opportunity came two nights later at Lake Tekapo located in the mountains 100 miles from any urban area. The view was stunning -- skies as dark as west Texas. A host of naked-eye and binocular objects virtually jumped out at us, including the remarkable Large and Small Magellanic Clouds, two companion galaxies to the Milky Way which are never visible from the U.S. (My wife, Jane, was actually the first to spot the Large Magellanic Cloud.)

I was in absolute awe. With each new object, I'd find myself saying to Jane, or mumbling to myself when no one was around, "I can't believe I'm actually seeing ____." The blank was filled in by one beautiful southern jewel after another.

If I'd seen nothing more during our visit, I'd still have felt a deep sense of fulfillment from that one night. But I saw even more -- like the spectacular southern lights -- which I'll relate in future columns.

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April 28, 2001

Stargazing in New Zealand

As previously promised, here's the first report on my recent journey to New Zealand. Being rather ignorant about the country, other than its being located in the southern hemisphere, my real interest was in seeing the night sky from New Zealand rather than seeing the country itself. And while seeing the southern night sky was an absolute thrill, I must first say a little about the country. Two words summarize, but oversimplify, its essence: beautiful and friendly.

New Zealand is situated a thousand miles southeast of Australia. The only more southerly land masses are Antarctica, far-southern South America, and a few small islands. It consists mainly of two long, slender islands extending nearly 1,000 miles end-to-end, and totaling just over half the area of Texas. The Dutch explorer Abel Tasman, in 1642, named the land Niuew Zeeland, after the Netherlands province of Zeeland.

It is a highly varied land consisting of coasts, beaches, sounds, mountains, lakes, rivers, waterfalls, forests, and even glaciers. Being located where two tectonic plates meet, it also has earthquakes and volcanoes -- most, but not all, extinct. Earth has many beautiful places, but it's hard to imagine such varied and pervasive beauty existing in one relatively small area. After touring for 4 weeks, I found myself suffering from beauty-overload, and thinking: ho-hum, just another waterfall.

New Zealand is sparsely populated with 70 percent of its 3.8 million people living in 5 major cities. The native Maoris (of Polynesian origin) settled a thousand years ago; Europeans (mostly English) began settling in the 1800s. Today, the Maoris represent less than 20 percent of the population, yet their culture (language, art, names of rivers, lakes, towns and the like) is a visible part of the fabric of New Zealand society, like native American culture is in Oklahoma and Arizona. English is the primary language, but Maori is also still in use.

Texans brag about being friendly, and mostly, we are. But the friendliness of New Zealanders made even this native Texan marvel. Their's isn't just nodding, waving or saying "hello" -- it's a proactive friendliness. With few exceptions, everyone we met went out of his or her way to be genuinely welcoming, helpful and eagerly conversational. For example, if you stand on the corner looking at a map for more than a few seconds, you can expect someone to stop and ask if they can help you, and then likely engage you in a conversation. We experienced this, not just at tourist sites, but virtually everywhere -- grocery stores, medical centers, gasoline stations, schools and universities.

Next time: my first views of the southern night sky.

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April 14, 2001

A New Central Texas Observatory

Imagine a youngster coming home from school with an image of the Andromeda galaxy. No big deal? How about if the child took the image using a 24-inch telescope -- and did it from her or his school classroom? Now imagine another student, working on a science fair project, analyzing the composition of a distant star using data he or she obtained with a spectrometer attached to that same telescope.

That's just a sample of what can come to pass thanks to the dream of members of the Central Texas Astronomical Society and some generous central Texans.

Last year, Charles and Dorothy Turner donated 5 acres of beautiful hill-country land between Clifton and Gatesville for the establishment of an astronomical research station. Then last month, Paul J. Meyer presented CTAS with $375,000 to build an observatory on that land -- equipped with a remote-controlled 24-inch research-grade telescope. These gifts, along with other donations of cash, services and goods, and hours of volunteer labor by CTAS members, are turning the dream into a reality.

According to CTAS president John McAnally, the dream was born of frustration as much as anything -- a classic case of turning lemons into lemonade. For several years, CTAS held its monthly star parties at Mother Neff State Park, and would still be there had it not been for a guard light installed in a residential yard adjoining the park. To the members' dismay, one light destroyed the location as a dark-site viewing field.

McAnally and former CTAS president Michael Robinson, while making an astronomy presentation in Clifton, happened to mention the society's plight. In the audience was Stan Gary, owner of Three-Mountain Retreat near Clifton, who invited CTAS to meet at his facility. The skies in this area proved to be as dark as any in this part of the state. Then along came Clifton rancher Charles Turner with the land gift, and the rest is history.

While the observatory will be the centerpiece of the research station, plans also include an education and visitor center, amphitheater, large viewing field and nature trails. These will be phased in as fund-raising progresses.

CTAS expects to make a decision on a telescope soon, and delivery of a research-grade telescope (which is custom made) takes 8-12 months. So within 1-2 years, kids (and adults) can be using the Paul J. Meyer Observatory at the Charles and Dorothy Turner Research Station. Stay tuned.

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March 31, 2001

Seeing the Southern Sky

As you read this, I expect to be enjoying an astronomical venture of my life time -- a trip to New Zealand. If you don't know where that is, don't feel bad. I had to look it up when friends invited us to make the trip with them. It is east of Australia, about one-fourth of the way around the Earth from Central Texas and just across the International Date Line.

Of most importance for stargazing, however, New Zealand's southern latitude. It is as far into the southern hemisphere as the upper half of the U.S. is into the northern hemisphere. Thus, weather permitting, I'll be able to see constellations, stars and other cosmic objects that are never visible from the U.S. and other midnorthern latitudes.

For example, our Milky Way galaxy has two smaller companion galaxies, the Large and Small Magellanic Clouds, which we in the northern hemisphere tend to forget about since we never see them. It's said that the LMC appears nearly as large as one's fist held at arm's length -- the width of 20 full Moons side by side.

There are also five 1st-magnitude stars never seen from our midnorthern latitudes. Two of these, Alpha and Beta Crucis, are in the Southern Cross, a tiny constellation with two other intriguing-sounding objects: the Jewel Box and the Coal Sack. I can't wait to see them.

Two other of these bright stars are Alpha Centauri, our nearest neighboring star system, and it's mate, Beta Centauri. The fifth is a star called Achernar which means "end of the river." The river refers to the constellation Eridanus which starts near Orion, where it is visible from our latitudes, but then runs deep into the southern sky out of our view.

Viewing the heavens from the southern hemisphere doesn't mean seeing an all new sky. Many constellations familiar to northern stargazers can also be seen from "down under," such as Orion, Scorpius, Sagittarius, Canis Major, Leo and Gemini. What will be different, however, is that these familiar constellations will appear upside-down -- as if being viewed while standing on your head from here. And, of course, their locations in the sky will be different. For example, it will likely feel strange seeing Scorpius high overhead rather than skimming along the southern horizon.

There's one final non-astronomical question I hope to get answered once and for all: In the southern hemisphere, does water going down a drain really spiral in the opposite direction from in the northern hemisphere?

I'll report on my experiences in a future column.

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March 17, 2001

Saying Goodbye to Venus

For the past several months, Venus has been the brilliant "evening star" blazing in the west. After becoming prominent in the evening sky last fall, Venus reached maximum height above the Sun in January and greatest brightness in February. She is now rapidly retreating into the Sun and will be gone in about a week -- so enjoy her while you can, soon after sunset low in the west.

This is a great time to view Venus through a telescope, or even binoculars held very steadily. Venus goes through phases like the Moon and now looks like a tiny crescent Moon.

On March 29 Venus passes between the Earth and the Sun in what is called inferior conjunction. Although she will be at her nearest to us at 26 million miles, she won't be visible. Even if the Sun's glare didn't interfere, Venus could still not be seen since we will be facing her unilluminated (dark) side. (It is for this same reason we can't see the Moon at new Moon.) After passing between Earth and Sun, Venus moves into the morning sky and becomes the "morning star" for the rest of the year.

As recently as a few decades ago, it was thought my many that conditions on Venus might resemble a garden of Eden. It was speculated (especially by science fiction writers) that Venus harbored life -- maybe even intelligent human-like beings.

Russian space probes in the 1970s emphatically ended such notions. Data and photos returned revealed an unbelievably harsh planet with conditions utterly incompatible with life as we know it, and certainly with human life. The surface temperature of Venus is 900 degrees, far hotter than kitchen ovens and hot enough to melt lead. Venus' atmospheric pressure, 90 times that of Earth's at sea-level, would crush organic beings.

And if the temperature and air pressure aren't enough to discourage life, the atmosphere's composition would. The predominance of carbon dioxide, while OK for plants, would not support Earth-like animal life which needs oxygen. But even more disagreeable to both plants and animals, Venus' extreme heat precludes the presence of surface water. The planet's only water is found high in the atmosphere as water vapor, and even that combines with sulfur dioxide to form clouds of sulfuric acid.

Thus, with scorching temperatures, crushing air pressure and an atmosphere lacking oxygen but rich with sulfuric acid vapor, Venus is anything but a tropical paradise. She's a beauty best beheld at a distance.

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March 3, 2001


Of all the jewels in the night sky, surely none is better- known than the Pleiades star cluster. Because of its celestial location, it is visible from virtually all the inhabited world.

Thus, it's not surprising that many cultures have ascribed these stars special meanings. Known as the Seven Sisters in our culture, others have seen the Pleiades as Seven Doves, Seven Virgins, Seven Little Nanny Goats, a Herd of Camels, a Hen with Chickens, Six Stars, a Wagon, Little Eyes, Seven Sages, and even a Great Spirit Grandfather.

Believing the Pleiades to be at the center of the universe, several ancient cultures from different parts of the world regarded them as the "seat of immortality." According to *Burnham's Celestial Handbook*, a Polynesian legend held that the Pleiades "was once a single bright star, broken into six during a battle of the gods."

The Pleiades have even served as an agricultural calendar. The 8th century poet Hesiod wrote: "When...the Pleiad stars arise / Before the Sun above the dawning skies, / 'Tis time to reap; and when they sink below / The morning-illuminated west, 'tis time to sow..."

The Pleiades have also inspired more recent poets. Emily Dickenson wrote: "I had a star in heaven; / One Pleiad was its name, / And when I was not heeding / It wandered from the same. / And though the skies are crowded, / And all the night ashine, / I do not care about it, / Since none of them are mine." And Lord Tennyson: "Many a night I saw the Pleiads, rising thro' the mellow shade, / Glitter like a swarm of fire-flies tangled in a silver braid."

To most, a naked-eye view of the Pleiades reveals 6 or 7 stars shaped like a tiny dipper, often leading to the mistaken idea that the Pleiades is the Little Dipper. Indeed, R.H. Allen in his 1899 classic *Star Names: Their Lore and Meaning* states: "As the group outline is not unlike that of the (Big) Dipper in Ursa Major, many think that they much more deserve the name the Little Dipper than do the seven stars in Ursa Minor."

Located in Taurus the Bull, the Pleiades is now seen mid way up in the west at 9 p.m. The nearby planets, Jupiter and Saturn, passing through Taurus this year, help make the Pleiades easier to find. A "young" 50 million-year-old cluster of several hundred newly formed stars, it is younger than Earth's dinosaurs. And while it appears larger and brighter than most star clusters, its apparent size and brightness are due to its proximity to us -- it's a neighbor at a "mere" 400 light years away.

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Feb. 17, 2001

The Winter Sky

It's time for our annual tour of the magnificent winter sky which displays some well-known constellations and bright stars. The most prominent feature of the season is the Great Winter Arc, a curved string of bright stars spanning nearly 90 degrees.

The Great Winter Arc begins at Canis Major's Sirius, the night sky's brightest star. When facing south around 9 p.m., you'll find Sirius half way between the horizon and the zenith (straight overhead). Remembering that your fist held at arm's length is about 10 degrees wide, look for Canis Minor's Procyon 26 degrees above and slightly left of Sirius. Then go another 23 degrees to the Gemini Twins, Pollux and Castor which are separated by 5 degrees. The arc ends 30 degrees further at Auriga's Capella.

Within the Great Arc are the constellations Orion and Taurus. Orion features two bright stars, Betelgeuse and Rigel as well as its distinctive three belt stars. Taurus, with the bright reddish star Aldebaran (the fiery "eye of the bull"), is also home to the famous Pleiades star cluster (also known as the Seven Sisters).

This year, Taurus is also hosting two of the brightest planets, Jupiter and Saturn. Hopefully the weather will clear so we can enjoy one of the most dazzling areas of the night sky.

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Feb. 3, 2001

Transparency and Seeing

When peering into the sky on a beautiful clear night, it seems there's nothing between us and the heavens. Perhaps you've said, "I could almost reach up and touch those stars." Sometimes we forget we're looking up from the bottom of a vast ocean of air.

We are reminded when clouds, haze or pollution make seeing stars difficult or impossible. This kind of visual interference determines what astronomers call the sky's degree of "transparency." Just as impurities can affect water clarity, they can affect how well we can see through the air.

There is yet another, but less obvious, way air interferes with stargazing. It acts as a lens that bends light rays, much like the lens in a telescope. But unlike a telescope, air scatters light rays in different directions rather than focusing them into one sharp image. This effect, which astronomers call "seeing," also causes stars to twinkle.

Seeing (and twinkling) varies from night to night, hour to hour, even minute to minute with changes in atmospheric turbulence. While twinkling stars have romantic and poetic appeal, they are not welcome to the stargazer -- the less twinkling, the better the seeing. Poor seeing is more of a problem for telescopic than naked-eye or binocular viewing. When a telescope magnifies an object, it also magnifies distortions from the air. If seeing is good, images are sharp and steady, but when poor, images look unsteady and out of focus.

Seeing and transparency have different effects, depending upon what is being observed. For inherently faint and fuzzy objects (like nebulae and galaxies), good transparency is more important than good seeing. The clearer (and, of course, darker) the sky, the better. When observing objects where sharp resolution is important (like planets, star clusters, and double stars), then seeing is more important. In fact, seeing can actually be better when there is a slight layer of haze to stabilize the air.

Excellent seeing and transparency (and the absence of light pollution) are the major advantages of space-based telescopes. There are many ground-based scopes larger than the Hubble Space Telescope, but the HST yields vastly superior images because it views the heavens from above our "ocean of air." (It should be noted that recent--and truly amazing--advances in computer technology are making it possible for ground-based scopes to compensate for and "filter out" some distortions in seeing.)

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Jan. 20, 2001

The Moon Visits 4 Planets

This fortnight sees the Moon visit four planets: Mercury, Venus, Saturn and Jupiter. It also provides a great opportunity to watch the Moon grow from invisibility to first quarter (and beyond).

The Moon is new at 7:08 a.m. Wednesday, the moment at which it passes between the Earth and the Sun in its monthly orbit around Earth. During new Moon the Sun illuminates the side facing away from us, thus the Moon seems invisible although it's in the sky all day with the Sun.

By Thursday evening, the Moon will be slightly east of the Sun and will set a few minutes after sunset. On that evening, it makes the first of its planetary passes as it visits Mercury. This will be the most difficult event to see as both will be very near the horizon soon after sunset. An ever-so-tiny crescent Moon will be to Mercury's lower left. (See below for spotting Mercury.)

Two days later, a slightly larger crescent Moon will be 7 degrees to the left of Venus, the beautiful "evening star." Since they are farther from the Sun, they will be easy to see up to an hour or two after dark. (Remember that your fist held at arm's length is about 10 degrees.)

By Feb. 1, the Moon will have grown to first quarter and will be situated 5 degrees from Saturn high in the evening sky. The next night, Feb. 2, it will be slightly larger and a mere 3 degrees from Jupiter, the brightest star-like object in the area. Although the glare of the Moon will interfere somewhat, this should be a very pretty grouping, centered around Jupiter. In addition to the nearby Moon, Saturn is 7 degrees and the Pleiades star cluster but 5 degrees from Jupiter. The entire group will fit inside a circle smaller than your fist held at arm's length.

After passing these four planets, the Moon will continue to grow (wax) until it become full on Feb. 8. It will also continue its eastward march across the night sky, appearing about 13 degrees further east than it was the same time the previous night. By full Moon, it will have reached the eastern horizon, and rise as the Sun is setting in the west.

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Jan. 6, 2001

The Night Sky in 2001

Welcome to the real 21st century and new millennium. It may have felt like they began last year, but as we've been told (many times by now), they really began January 1, 2001.

And for those of us who remember, didn't 2001 seem like the distant future when we watched *2001: A Space Odyssey* in 1968? Yet, here we are, now living in that "distant future." Perhaps you share my disappointment that we're not yet the space-farers of Arthur C. Clarke's and Stanley Kubrick's vision. But hopefully you share my gratitude that we still have the same big, beautiful night sky to enjoy.

So what does 2001 hold for stargazing? In addition to the perennial night sky wonders, the year promises some interesting, even if not spectacular, sights.

Venus, the "evening star" through March, will become the "morning star" from April through late fall. Jupiter and Saturn, in the evening sky until spring, move to the morning sky in the summer, then return to the evening in the fall.

The real planetary "star" of 2001 will be Mars. Now rising after midnight, it moves into the evening sky in early spring. In early summer it reaches opposition and comes closest to Earth. It will shine as bright as Jupiter, but with a fiery orange color. Then as we move further away, Mars will gradually fade to its more typical brightness -- that of a bright star -- and remain in the evening sky throughout the rest of 2001.

There will be some good conjunctions when planets or the Moon pass near each other or near a bright star. The show stopper will be an August early morning Venus-Jupiter pairing.

The year will see a peak in sunspot activity. While you won't actually see sunspots (unless you have proper viewing equipment), there will be a chance of seeing the aurora borealis (northern lights) from southern U.S. latitudes -- so be alert.

Unfortunately, 2001 won't give the U.S. any good solar or lunar eclipses, nor are any dramatic comets due to return. But there's always a chance for surprises, like 1996's Comet Hyakutake -- so keep your fingers crossed.

While 2001 may not quite be a space-odyssey year, it can still be a fun year for looking skyward.

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