Winter sure didn’t sneak up on us this year. Astronomically, winter officially begins on Sunday Dec. 21 at 7:04 am EST, which is nice, because the beginning of winter is the beginning of the end. From Sunday on, the days will get longer, and West Michigan usually begins to see a bit more clear sky.

When it does clear up, the winter sky is always a wonder.

Astronomers have mapped the sky onto coordinate systems to help locate things. The simplest useful coordinate system is the altitude and azimuth system. Everyone has their own altitude and azimuth coordinate system. The center of your coordinate system is the point directly over your head, called the zenith. The altitude of the zenith is 90 degrees.

The altitude of the horizon is 0 degrees. Anything between the horizon and the zenith has an altitude between 0 and 90 degrees. Halfway is 45 degrees.

Azimuth is the compass direction you need to face in order to see something in the sky most conveniently. Around the horizon, north is 0 degrees, east is 90 degrees, south is 180 degrees and west is 270 degrees.

Your sky is divided into an east half and a west half by an imaginary line that runs from the north point on the horizon, overhead through your zenith, to the south point on the horizon. This line is called the meridian. The meridian is useful because as celestial objects rise and set, they reach their greatest altitude, and thus are easiest to see, when they cross the meridian.

When the clouds take a break from casting gloom over West Michigan, look along the meridian to the south a couple of hours after sunset for some of the brightest, most conspicuous stars and constellations.

Canis Major and the brightest star in the sky Sirius are low in the southeast, Orion, with bright blue Rigel and glowing red Betelgeuse, is at an altitude of about 45 degrees on the meridian, and Taurus the Bull, with the star Aldeberan marking his glowing red eye, are higher and to the west. Also look for the Pleiades, the tight cluster of stars, sometimes called the seven sisters, riding on Taurus’ back.

Closer to home, look for Jupiter and Venus low in the west and southwest. Jupiter at an azimuth of about 200 degrees and an altitude of about 30 degrees; venus at an azimuth of about 250 degrees and at an altitude of about 20 degrees. Both planets are very bright.

Also, early in January, you may catch a glimpse of fleet-footed Mercury. The closest planet to the sun is best situated for viewing on Jan. 4 2009 when it is at it greatest eastern elongation. Look for Mercury then at an altitude of about 10 degrees above the west-southwest horizon as soon after sunset as the stars begin to shine.

In the morning, you may see Saturn drifting between Leo and Virgo across the meridian at an altitude of about 50 degrees. But don’t look for Saturn’s rings these days (you would need a telescope anyways); Saturn’s thin ring system is oriented just about edge-on toward earth. Saturn’s rings won’t be visible again for about a year.

Happy holidays, and enjoy the snow. It won’t be long until we see more of the sun and sky.

This column originally appeared in the Grand Haven Tribune on 19 December 2008.

Six o’clock in the morning really isn’t all that early. Even if you’re not an early riser. You might want to consider doing something out of the ordinary one morning in the next couple of weeks: get up by 6 am and have a look at the sky.

The morning sky this time of year is just beautiful. And because we haven’t flipped out clocks back to standard time yet, the sky is dark and the stars are bright until even after 6 am.

The stars and constellations rise four minutes earlier each day compared to the day before. Because of this, the morning sky offers a sneak preview of this winter’s evening sky.

One reason you might take advantage of this week’s sneak peak, even if it means getting up and out in your backyard a bit earlier than you normally would, is that its warm now. If you wait until winter to see these sights, you’ll have to stand out in the snow and cold.

Another reason you might want to have a look is that now at dawn some of the northern hemisphere’s most impressive sights are arrayed high in the sky.

So, get up and outside to a dark place around 6 am. If you have a pair of binoculars, bring them with you and…

Stand in the place where you live, now face north…

Look to your right (to the east) to see the Big Dipper balancing on its handle. Let the top two stars in the Dipper’s bowl point you to the left to the North Star so that you’ve got your bearings.

Now face west…

High in the sky and to your right look for Cassiopeia — the giant W in the sky. Low on the horizon in front of you, if you’ve got a good view to the west, is the giant square of Pegasus balancing on one of its corners.

With your trusty binoculars, or even with your naked eyes if it is good and dark out, scan slowly the sky about halfway between Cassiopeia and the topmost star in Pegasus until you find the Andromeda Galaxy, looking like an oblong cotton ball in the dark sky. At a distance of 2.5 million light years, the Andromeda Galaxy is the most distant object you can see with your naked eye.

To the south, and low and to your left is Sirius, the brightest star in the sky. Straight in front of you is mighty Orion, and above him is Taurus the Bull, his face looking like a V with bright red Aldebaran marking his right eye. Continuing along a line from Orion through Taurus you’ll spy the Pleiades, a tight knot of stars that looks like a tiny little dipper.

For a final treat with your binoculars, scan the sky around Orion’s sword looking for the famous Orion Nebula, a glowing cloud of gas and dust. Then aim your binoculars at the Pleiades and let your gaze drift along a ling back to Cassiopeia. All throughout this region, stretching along the Milky Way, you’ll spy stars and star clusters, probably more than you’ve ever seen before.

While you take this all in, in words offered by the band R.E.M: “You’re feet are going to be on the ground; your head is there to move you around.” And as you make your way back inside to take on your day, “Think about the place where you live and wonder why you haven’t before.”

This column originally appeared in the Grand Haven Tribune on 10 October 2008.

Some say that autumn is the best time of year in West Michigan. If so, then the good times officially roll on Monday, Sept. 22 at 11:44 AM EDT. At this instant the sun will cross the celestial equator — earth’s equator projected out onto the sky — heading from north to south, marking the astronomical beginning of autumn.

Astronomers call Monday the autumnal equinox. Equinox means roughly “equal night”, which isn’t quite the case on Monday. The sun will rise on Monday at 7:34 AM and set at 7:41, making the day about seven minutes longer than the night. It isn’t until Thurs., Sept. 25 that the sun sets exactly twelve hours after it rises. On Monday, the day is a bit longer than the night because the sun is a disk, and sun rise and set are measured from the very top part of the sun. Anyway, it’s just a matter of minutes.

But on the equinox one thing is true: the sun rises due east and sets due west for every observer on earth. For us in West Michigan, where most of the roads are laid out east-west and north-south like the rulings on a sheet of graph paper, the equinox sun rise and set can be blinding on the commute to and from work. Take an extra pair of sunglasses with you in the car.

More and more darkness gives us more and more time to wonder at the night sky. One nice thing to look for right now, shortly after sunset, is a cluster of planets in the west over the lake. Venus, Mars and Mercury are presently clustered in a relatively tight little bundle that sets in the west just thirty minutes or so after the sun. Venus stands out easily because she is so wonderfully bright, but to see her companions you might want to bring along a pair of binoculars.

If you can’t get out to see the trio of planets next week, you’ll still have opportunities to see Venus. As fall wears on, goddess of love will slide higher and higher above the horizon in the west after sunset, growing brighter and brighter with each passing day.

Jupiter continues to hold his place in the sky in the constellation Sagittarius above the horizon in the south. But as the days go by, he’ll slip more and more to the west at sunset, to be out of view by early winter.

At dawn we can look forward to seeing more and more of mighty Saturn. Right now, the ringed marvel rises just about a sunrise, but as the days grow shorter, he will rise earlier and earlier. By early December, Saturn will be high above the horizon in the southeast before sunrise.

Saturn’s rings are normally an ideal target for testing out your goto telescope, but this year and into next, the relatively razor-thin rings are oriented edge-on to earth, so we cannot get a good view of them.

Mercury will make a brief appearance in the east before sunrise in late October. Catch him if you can.

All the while, Orion and his cohorts — Taurus the bull, Gemini the twins, and Orion’s hunting dog Canis Major — are rising earlier and earlier to take the familiar places high in the cold sky by the beginning of winter.

Winter will be officially upon us on Dec. 21 at 7:04 EST. And while the weather will after that grow steadily colder and snowier, the nights will actually begin to grow shorter as we make our way back around to the spring rains and warm summer nights.

Its official: summer began at 7:59 pm Friday, June 20. And summer is a great time for stargazing. Here are a few things to watch for.

For the next few weeks you can catch the latest sunsets of the year. The time of sunset drifts steadily later from winter to summer until just after the summer solstice when the late-ward drift halts and the days begin to get shorter again. The latest sunset of the year here in the Tri-cities area is 9:28 EDT.

Not so popular are the earliest sunrises of the year, which also take place around the summer solstice. The sun rises tomorrow at 6:05 am, giving us a total of almost fifteen-and-a-half hours of daylight.

Presently at dusk, the planets Saturn and Mars lie low in the west in the constellation Leo. Saturn and Mars will drift further westward as summer progresses, and will be out of the picture by mid September.

Mercury will make a brief appearance with Mars and Saturn in the western sky just after sunset during the first week of September. But the best opportunity to see Mercury is in the mornings around July 1 when the planet reaches what’s called greatest western elongation. At greatest western elongation, Mercury is about 22 degrees west of the sun. That’s right, west, which is why we will see it rise in the east in the early morning hours before sunrise.

Jupiter will dominate the sky this summer. Presently, Jupiter is low in the east after sunset, but as the season wears on, will rise earlier and earlier to be higher in the sky at dusk. Jupiter will be opposite the sun in the sky and high overhead at midnight by early July.

You can look forward to bright full moons on July 18, Aug. 16, and Sept. 15. And the darkest nights of the summer, the nights on which the moon is new, will be July 3, Aug. 1 and 30, and Sept. 29. The moon will be new twice in August, but there is no special name for this circumstance, as there is for the second full moon in a calendar month — a blue moon. Maybe you can make up a name for the moon on Aug. 30 this year.

The dark, new-moon nights of summer, are perfect for drinking in the Milky Way. Our view of the Milky Way is best on dark summer nights. The center of our galaxy and the brightest portion of the Milky Way lie towards the constellation Sagittarius. Look for Sagittarius low in the south late at night in August. Jupiter will be there too. If you look from a dark spot, you will see Jupiter, Sagittarius and the Milky Way stretching high overhead.

The solar system’s best fireworks display — the Perseid meteor shower — is always in mid August. This summer, the Perseids will peak on the evening of Aug. 12. Of course a dark sky is best for viewing shooting stars, so to get the best of the show, you’ll have to stay up late. The moon will set well after midnight. But what a night to pull an all-nighter: watch the bright, waxing gibbous moon set over the lake and then lay back to see the Milky Way and some bright shooting stars.

Summer ends with the beginning of autumn on Sept. 22.

Spring arrives with a full moon late next week. The sun passes the vernal equinox — a point in the sky in the constellation Pisces — at precisely 1:48 am EDT on Thursday, Mar. 20, marking the official beginning of spring.

Look for the sun to rise due east on Thursday morning (and for the next few days), making your morning drive to work on Lake Michigan Ave. and other West MI East-running roads a challenge if it’s not cloudy. Then look for a bright full moon to rise in the west at sunset. March’s full moon, which is technically on Friday, is called the Worm Moon, hinting that the ground will soon thaw for the worms to begin their spring work preparing the soil for planting.

Over the next three months, until summer begins on June 20, sunrise in West MI will drift from 7:47 am to 6:05 am, sunset will slide from 7:58 pm to 9:28 pm, and the duration of daylight will lengthen from just about 12 hours to nearly 15-and-a-half hours. Thanks to the new daylight saving time rules, we are under daylight time the entire season.

The date of Easter is tied in a complicated way to the spring full moon. This year, because the moon is full so soon after spring begins, Easter is celebrated much sooner than average. Easter Sunday is Mar. 23.

In the sky shortly after sunset, Winter’s ruling constellation Orion will slowly settle to the western horizon as spring segways to summer. As Orion falls away at dusk over the season, look for Saturn high in the southeast sky in the constellation Leo. And look for Mars in the constellation Gemini nearby to the west of Saturn. Watch Mars steadily drift closer to Saturn as the refreshing spring days go by, passing through the constellation Cancer in May and reaching Leo with Saturn in late June and early July.

Watch also for Mercury to become visible above the western horizon just after sunset beginning in late April. For a period of a few days around May 14, when it reaches greatest elongation, Mercury will be best positioned for viewing after sunset in the west in the constellation Taurus.

In May, the moon can guide you on a tour past the early evening’s visible planets. On May 6, the moon, then a very thin crescent, will slip past Mercury. By May 9-10, the moon will have grown to nearly first-quarter — what looks like a half moon — and will glide past Mars, and a day or so later will sail past Saturn.

If your a morning person, look for Jupiter before sunrise low in southeast in the constellation Sagittarius. Watch over the season as Jupiter climbs higher and higher above the southern horizon.

But don’t look for Venus this spring; she will be lost near the sun until sometime this summer.

Other targets of opportunity this spring include two meteor showers: the Lyrids on Apr. 22 and the Eta Aquarids, which are debris from Halley’s Comet, on May 5.

Closer to here and now you might enjoy watching for the ISS and Space Shuttle to fly overhead. The spacecraft should make several high and bright visible passes over West MI on the mornings of Mar. 17-20. Details about these West-MI viewing opportunities:

• On May 17, look for the spacecraft to rise above the horizon in the northwest at 6:57 am, fly to about 45 degrees above the hoizon in the north northeast by 6:59 am, and settle back to the horizon in the east southeast at 7:02 am.
• On May 18, they should rise in the west northwest at 7:19 am, reach an altitude of about 60 degrees above the southwest horizon by 7:22 am, and sink into the southeast horizon by 7:25 am.
• On May 19, they should brighten into view as they move into sunlight high above, about 40 degrees above the horizon in the north at 6:09 am, and climb to about 45 degrees above horizon in the north northeast by 6:10 before sinking below the horizon in the east southeast at 6:12 am.
• And finally, on May 20, which might be the best viewing opportunity, the shuttle and ISS should pop into view at 6:31 am about 40 degrees above the west-northwest horizon, sail high overhead in the southwest by 6:32 am, then settle into the south-eastern horizon at 6:35 am.

These predictions are spcific to Grand Haven, and may change as the shuttle and ISS orbits change slightly. I will try to update these predictions if they do change; visit heavens-above.com for detailed viewing forecasts for any location.

Look for a new post on or about 22 March 2008.