A month for heavenly meetings

Wednesday, January 7, 2015

We have a busy month ahead of us, what with planet-to-planet and moon-planet meetings throughout the month even though it is cold outside, we will keep our binoculars and telescopes warm with all the use.

First off, tonight, Wednesday, Jan. 7, be outside about a half-hour after local sunset for a nice view to the west of the bright planet Venus and tiny Mercury.

Binoculars will be needed because the pair will be low on the western horizon still in the glow of sunset. They will be at their closest on Sunday, Jan. 11.

If you are not sure what time the sun sets in your area, point your favorite web browser to www.sunrisesunset.com indicate your state and town and get a month's worth of data.

Also available from them are civil, nautical, and astronomical twilight times; moon phases, moon rise and set times; and the approximation of your latitude and longitude.

Just be aware, that is a lot of information to print on a single calendar and it may spread across two or more pages. Get a preview of your calendar before you print, then use "ctrl+p" to print it out.

Although the time of sunrise has stayed the same since the first of the year, the time of sunset has gone from 1631 hours to 1636 hours giving us five more minutes of daylight.

It will be fun to follow Venus and Mercury each evening at the same time for the next week as they draw closer together until Jan. 14, when Mercury reaches its greatest elongation from the Sun then starts the journey back.

Later in the evening, about 2200 hours, go out and look just above the eastern horizon for a just-passed full moon and the planet Jupiter. They will be about 5 degrees apart. This is the first of many moon-planet meetings for the month.

Keep your binoculars and telescopes dusted off because next week, Jan. 14, the planets Mars and Neptune will be getting together. On that date they will be in the same binocular field of view.

Keep watching them each evening as Mars moves closer until Monday, Jan. 19, when they will be at their closest.

Now, here is an event that we file in the "Odd Strange and Curious" astronomy file. On Sunday, Jan. 4, the Sun and Earth were at their closest for the year. Now I know what the next question will be.

If they are so close, why is it so cold here.

There are a couple of answers for that question. First, remember the 23.5 degree tilt of Earth's axis. Right now Earth's northern hemisphere (where we live) is tilted away from direct sunlight so we don't get the full benefit of its warmth.

Second, Earth's orbit is not a circle, it is an ellipse and what's more, the Sun is not even at the center of the ellipse.

If anything, we can take comfort knowing that winter is the shortest of the seasons at an average of only 89 days while summer lasts 94 days. In case you were curious, autumn is 90 days and spring is 93 days.

If anything, shed a tear for the good folks south of the equator, Earth is tilting them toward the full force of the close Sun and it is hot.