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Sky Report, December 2020 - January 2021

12/18/2020

Evening Sky

Jupiter (magnitude -2.0) and Saturn (0.6) become visible in the southwest evening twilight. The two planets currently appear about one moon-width apart and continue to inch closer together until December 21. That evening, Jupiter and Saturn appear just 0.1° apart, meaning the two planets can be seen in the same telescopic field of view at low power. Both planets currently set just after 7:00pm, but by mid-January they will set about 45 minutes after sunset.

Mars (-0.7) becomes visible high in the southeastern sky as darkness falls. The red planet currently sets in the west just before 2:30am and becomes dimmer over the next month. By mid-January, Mars shines at magnitude 0.1 and sets in the west-northwest around 1:30am. The moon appears about 6° below Mars the evening of December 23. Then on the night of January 20, the first quarter moon appears just below Mars, with distant Uranus (5.8) directly between them and closer to Mars.

Mercury (-0.9) returns to the evening sky in mid-January, setting in the southwest about an hour after sunset. The innermost planet sets later each evening but rapidly dims until reaching magnitude 1.1 by the end of the month. The week of January 17, especially later that week, should provide the best viewing.

Morning Sky

Venus (-4.0) currently rises in the east-southeast around 6:00am, and about a half hour later by mid-January.

Meteor Showers

The Ursids meteor shower is active from December 17 to 26, peaking the night of December 21-22. Normally a lower volume shower, this year the Earth passes near several past debris trails of comet 8P/Tuttle, the source of the Ursids. The debris trail left in the year 829 is predicted to produce the most favorable peak between 10:00-10:30pm on December 21. Unfortunately, west coast observers will need to deal with the first quarter moon. To view the Ursids, look to the northern sky, about half way between the horizon and zenith.

Moon Phases

First (12/21), full (12/29), last (1/6), new (1/13), first (1/20), full (1/28)

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How to choose a telescope for astronomy

12/16/2020

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(Thanks to FoG founding member Mark Thorson for most of the following.)

New to astronomy? Thinking about your first telescope or a gift for a budding astronomer?

Here are a few tips to help you out, and links to helpful articles.

Find a good sky as best you can.

Sky conditions are more important than the equipment you use for observing. Even expensive sophisticated telescopes do not overcome poor sky conditions.

City lights are one challenge but so are clouds and humidity, temperature changes (rising heat from your driveway, for example), city smog, forest fire smoke, and so on.
If you're not looking at the moon, choose nights close to a new moon so the full moon doesn't wash out the rest of the sky. If you do want to look at the moon, choose nights with a half- or crescent moon, when you'll have more contrast to see details.

Use binoculars. They will help you focus on the kinds of objects you like to watch, and this will help you choose the right telescope later.

Most binoculars are easy to carry around and to focus. That means you're more likely to use them - and to enjoy exploring the sky. (Here are some binocular recommendations).

Look at the moon and its craters, look at the other planets, maybe try looking for constellations or galaxies or star clusters in the Milky Way.

Never look at the sun through binoculars (or telescopes), but you can focus the sun's image onto a sheet of paper. It's a pretty neat way to see sunspots or an eclipse.

Caution! Solar observing requires special equipment and experienced supervision.

Never allow unsupervised operation when the sun is above the horizon.
Accidentally pointing the telescope at the sun (even if cloudy) and peeking through the eyepiece could cause permanent blindness in seconds!

Try someone else's telescope. Ask your local astronomy club for opportunities to look through their different types of telescopes. Ask members about their telescopes, what they like or dislike about them, and what they'd choose today.

When we return to public events, after the pandemic, watch our calendar for our sidewalk astronomy or other viewing events. The public is always welcome!

Starting to narrow things down? Here are a few more tips.

Focus on a telescope that is easy to operate. Easy to use means you're more likely to use it.
Don't "save money" by buying a department store or toy store telescope. It's just frustrating. You'll be much happier sticking to binoculars or by checking out the article below.
High magnification (say greater than 100x power) does not usually improve quality of images.
An equatorial mount helps track objects in the sky as the earth turns - but avoid these to start. They are more expensive, heavier, and difficult to use.
Similarly, GoTo electronically-operated telescopes sound good: dial in what you want to see, and the computer points the telescope at the correct object. But set up can be very finicky. Don't pay money to be frustrated!
Instead, get a (Newtonian) reflector telescope with a Dobsonian mount.These are much easier to move and more intuitive to use.
Reflector telescopes are a better first choice than refractor telescopes because you get more telescope light gathering aperture per dollar spent.