YOU CAN DO ASTRONOMY
The Future’s in the Stars
Doing astronomy isn’t limited to professional observers and big telescopes. Hundreds of thousands of amateur astronomers around the world also watch the sky. Some simply go outside, look up, and enjoy the view. Others set up telescopes and do astrophotography, and a few even contribute to scientific research. It’s easy to get started—you just step outside on a clear, dark night and look up. If you’re a novice stargazer, what you see will amaze you, and before long you’ll want to know more about the objects you observe.
What’s Up There
During the day, there’s usually only one star that’s visible: the Sun. The Moon also appears in daylight during part of the month. At night, you have the planets, the Moon during part of the month, the stars, and galaxies to explore. Star charts can help you find your way around the sky. These are maps that show what’s up in the sky in the month or season you’re observing. There are many sources of star charts online as well as in such magazines as Sky & Telescope and Astronomy.
People often think that they have to buy huge telescopes and cameras to “do” astronomy. That’s not so. Naked-eye observing is the best way to get started. This kind of astronomy is as easy as looking at the sky and learning your way around the stars. There are many good books for casual observers that help you explore the stars and constellations in more detail. One of the best and easiest to learn from is Find the Constellations by H. A. Rey. Originally written for children and their parents, it is a great beginner’s book. The Stars: A New Way to See Them, also by Rey, has more details and is written for older children and adults.
Equipment Fever
If you want to get some equipment, think about what you want to see. What you’re trying to do is make distant things look closer so you can see them better. The best way to start is with a pair of binoculars. They help magnify the view and are easy to use. Once you get to know the sky and have some favorite objects you want to study in more detail, then think about getting a telescope.
The type of telescope you buy will depend on which celestial objects you want to view. Before you plunk down hard-earned money on optics, look through other people’s telescopes. Ask them a lot of questions, and do your homework before you buy. There are good equipment-buying tutorials from Sky & Telescope and Astronomy magazines, so check those out, too.
What to Observe
The easiest things to observe in the sky are the planets, particularly Mercury, Venus, Mars, Jupiter, and Saturn. They’re visible to the naked eye, and they stand out because they’re usually brighter than the stars. If you want to try finding Uranus and Neptune, you’ll need a good backyard-type telescope. The next things to spot are double stars. After that, you can look for star clusters such as the Beehive in Cancer, or the Double Cluster in Perseus. If your skies are really dark, you should be able to make out the Milky Way, particularly in the summer and wintertime skies. Those are just a few of the many gorgeous sights that await you as you explore the skies!
Easy Targets to Observe
If you have binoculars or a small telescope, check out these sky sights:
- The Moon—you can see individual craters and other surface features
- Mars—through a small telescope, you can spot its dark and bright areas and its polar caps
- Jupiter—through binoculars you can look for its four brightest moons
- Saturn—look for its rings through binoculars and the bright moon Titan through a telescope
- The Andromeda Galaxy—near the W-shaped constellation Cassiopeia. It’s most visible from August through part of March; it is just barely visible to the naked eye
- The Orion Nebula—best viewed from November through mid-April, just below the three stars in Orion’s belt
- Alcor and Mizar—a double star in the bend of the handle of the Big Dipper
- Albireo—a beautiful double star in the constellation Cygnus, best visible at night July–November
Observing Mercury from Earth
It’s very easy to see five of the planets from Earth with the naked eye. They look like bright points of light against the backdrop of stars (Uranus and Neptune are too faint to see without a good telescope). Mercury is challenging because it orbits close to the Sun. However, there are certain times when observers can see it for a few days. Look for Mercury at sunset during a time called greatest eastern elongation, and at sunrise during greatest western elongation. Elongation is a term that refers to the points in Mercury’s orbit in the sky as seen from Earth when the planet is most distant from the Sun. The table here gives you the best time, date and position (in degrees from the horizon), and brightness of Mercury over the next few years. So, on October 9, 2013, for example, it will appear as a bright pinpoint of light in the western sky 25.3 degrees east of the Sun (which is setting). In November, it will appear in the morning sky on November 18, 19.5 degrees west of the Sun (so look for it before sunrise).
One note of caution: Make sure the Sun is not in the sky when you look for Mercury. You don’t want to injure your eyes by looking directly at the Sun.
Light Pollution: The Astronomer’s Bane
Every night people pollute the sky with unnecessary lights. This washes out the view of the sky and is called light pollution. It’s not just a threat to seeing the stars—it also causes health problems and costs money to keep unnecessary lights on where they’re not needed. Light pollution lets people living in urban areas see only the brightest stars and planets in the sky. In many large cities, people only see a few stars, and there are many who have never seen the Milky Way.
No one is advocating that we abolish the light bulb. There are ways to safely light our homes, streets, and landscapes and keep our view of the stars. People can help by turning off unnecessary lights around their homes. If lights are necessary, aim them directly where they are needed. And remember: The stars are everyone’s legacy.