Make Way for the King of Spring

During March, we begin the slow farewell to the familiar constellations of winter. Taurus the bull, Orion the hunter, and Canis Major the big dog are still visible this month, but every evening they set just a little earlier. By May, they will be lost in the glow of sunset.

Meanwhile, spring constellations are coming into view. One of the most famous of these is Leo the lion. The head of Leo looks a bit like the hook of a coat hanger or a backwards question mark. The bright dot at the bottom of the question mark is a star called Regulus that marks the regal heart of this king of the celestial jungle.

Just to the east of Regulus is the planet Saturn, which appears pale yellow to the unaided eye. Your average binoculars will show an oval dot instead of a round dot like the other planets. Saturn's beautiful rings will show up nicely in a good small telescope.

Just above Leo is Ursa Major the great bear. Most people are more familiar with the part of Ursa Major called the Big Dipper. Ursa Major is one of the 88 official constellations recognized by astronomers around the world. By contrast, the Big Dipper is just an unofficial asterism, a popular pattern of stars. Whatever you call it, it's especially easy to find this month, high in the sky in the early evening.

Now that you have found the Big Dipper, you can use it to find the North Star. Draw an imaginary line through the two stars on the outside of the bowl of the Big Dipper, out of the bowl until you reach a star of similar brightness.

Unfortunately, many people think the North Star is the brightest star in the night sky, but it really only ranks 47th on the list of bright stars. Its official name is Polaris, and that’s no accident.

Imagine drawing a line from the south pole of the Earth through the center, to the north pole. That’s the Earth’s axis, the imaginary line that the planet rotates around. Now imagine extending that imaginary line out from the north pole all the way into space. The line runs almost exactly into Polaris. Now draw a line from Polaris straight down to the horizon, and you’ve found the direction north.

Take the time to watch the stars over several hours as the Earth rotates. All the stars appear to circle around Polaris, while Polaris itself stays in the same spot in the sky all night. There’s nothing else really special about Polaris. It’s just a big cosmic coincidence that it happens to be right in line with the Earth’s axis.

Mars, near Gemini the twins, continues to fade after its close approach to the Earth in December. As Mars and Earth get further apart, the planet looks fainter to our eyes. If you look at Mars in a small telescope, you won't see much if any detail. It will look like just a pale pink dot, but notice that it still looks round, unlike the pinpoint dots of the stars - or the oval of Saturn.

Spring Equinox

This year, March 20 marks the date of the spring equinox for everyone living in the Northern Hemisphere. On this date, the length of day and night are nearly the same. From this date until the summer solstice in June, there will be more hours of daylight than night.

In the Southern Hemisphere, the situation is reversed. March 20 is the first day of fall, and the days will get progressively shorter until the first day of winter, in June.

It's often said that the only time you can balance a raw egg on end is on the spring and autumn equinoxes. This is absolutely not true! It takes a little skill and lots of patience to balance an egg on end, but it really can be done any day of the year.

Spring Launch

The new Sudekum Planetarium and Sky and Space Wing open this summer. To get ready for the launch of this world-class experience, the Science Center is offering a day of preflight training for future “Nashtronauts” on Saturday, March 22, from 10:00 AM to 5:00 PM.

Nashtronauts of all ages can participate in a variety of fun and educational astronaut training activities. This will also be your first chance to register for the new online training program that takes visitors on a mission from the Science Center to the planets and beyond!

Spring a Star Party

Join us and the Barnard Seyfert Astronomical Society at the Ridgefield site at Edwin Warner Park for a FREE public star party, from 8-10 PM, Saturday, April 12. If the weather’s clear, telescopes will be set up for everyone to get a good look at the Moon, Mars, Saturn, and plenty of springtime constellations.

If the skies are cloudy or worse, the event will be cancelled. Please consult the Sudekum Planetarium web site or call Astroline at (615) 401-5102 before traveling to the observing site.

The next star party after this is scheduled for May 3 at the Visitor’s Center at Longhunter State Park.