Ah! October! If you ask me, October is the best month of the year. Not too cold, not too hot, and one of the best months of the year to see some great things in the heavens!
October is often an excellent observing month for amateur sky-watchers. The weather is great and the skies are often quite clear. The Earth is a bit cooler and this means that, at night, less heat is radiated back into space. This means that there is often less turbulence at night and objects can be seen with greater clarity than many other times of the year.
If you would like to see Jupiter, perhaps at its best all year, get up at dawn and view it. It will be found about one third of the way up from the eastern horizon and it will be bright. The air will be cool then, and if it is calm, you might see good detail on the planet itself and the Galilean moons should be quite visible in even a small telescope. Sometimes, a good pair of binoculars, if they are properly propped against a building or an automobile, will just show Jupiter as a disk and some of the moons might be visible. Get the best focus you can on a far away object and then turn the binoculars on Jupiter.
Mars and Saturn will soon disappear over the western horizon as sunset comes on. As we move along our orbit, and these two planets each move along their own orbits, Mars and Saturn will "disappear" for awhile, only to reappear at dawn next year. Early next year, dawn will be a good time to see these planets but it may be too cold or stormy to enjoy the time you spend viewing them.
We are moving towards a time of the year when the Milky Way, at least the arms of it "inward" from us, will not be visible in the evening. (There is a winter Milky Way, but it is difficult to see.) I usually think of October as the last really good month to see the Milky Way. Get your binoculars and give it a last scanning -- it is always rewarding.
Two eclipses of different kinds will occur in October. On the night of Oct. 7, there will be a total eclipse of the Moon. It will mostly be visible from the western part of the U.S., extending to New Zealand. We might get a good view of at least a partial eclipse of the Moon in Arkansas on that night.
On Oct. 23, there will be a partial eclipse of the Sun visible in many northern latitudes. In Arkansas, we might just see it but it will not be as prominent as it would be if we lived farther north. If you want to get all the details, use a search engine and type in something like: Oct. 23, partial eclipse of the Sun. You should get a good map of where the eclipse can be seen best and the time for best viewing where you live.
Partial eclipses of the Sun and Moon are not rare. Even total eclipses of the Moon are fairly common. It is total eclipses of the Sun that are rare and I have yet to see one. I did get to see a 98 percent partial eclipse from the Hawaiian Islands some years ago, but this was nothing like a total eclipse.
The mechanism of both partial eclipses and total eclipses of the Sun are almost exactly alike. The Moon is the same apparent size of the Sun at certain times of the year. If the Moon passes directly in front of the Sun from our perspective, we see a total eclipse. If the Moon's apparent image just grazes the Sun,and does not totally eclipse our view of the Sun, a partial eclipse results. It appears as if a big bite has been taken out of the Sun! However, the Sun will still be very bright and it will be dangerous to look at the partial Sun, even if a significant chunk of it has been eclipsed. Do not look at even a partial eclipse of the Sun with your naked eye! The best way to see such an eclipse is to use a telescope to project the image onto a piece of white card or paper. This will be completely safe and a number of people may view the image at the same time. Do not train the telescope on the Sun for more than a few seconds at a time -- putting the telescope on the Sun longer than this can damage the optics in the eyepiece.
Enjoy the good weather of October. Get out there and look at the wonderful universe. It will be inspiring.
-- Dr. David Cater is a former faculty member of JBU. Email him at [email protected]. The opinions expressed are those of the author.
General News on 10/01/2014