A thin, crescent moon greets us in the western sky at dusk when October starts. See Antares and Jupiter in the southwest and Saturn in the south. Venus and Mercury are evening object, too. But they’re barely there, setting almost as soon as the sun does.
The moon passes by Antares in the claws of Scorpius on the 2nd. It passes Jupiter on the 3rd and Saturn on the 5th. For observers in the southern Atlantic Ocean and southern Africa, Saturn is occulted. The moon is just past first quarter then.
After full moon on the 13th, watch for the moon to pass through Taurus. It will pass by Aldebaran in the V of the Hyades on the 17th. The moon, about a day before last quarter, passes in front of the star Tejat in the feet of Gemini on the 19th for viewers in south Asia. A waning crescent passes by Regulus on the morning of the 23rd. And a very thin crescent will be near Mars on the morning of the 26th.
Specific dates on the moon’s phases this month: first quarter on the 5th, full on the 13th, last quarter on the 21st, and new moon on the 28th.
Lunistice is on the 5th when the moon is 22.8° south of the equator. The moon goes north of the equator on the 13th. It reaches 22.9° north on the 20th. And it’s on the equator going south on the 26th.
Apogee on the 10th has the moon 405,900 km away. Perigee on the 26th is at 361,300 km.
October presents several meteor showers:
The Southern Taurids peak on the 10th. The moon is nearly full that night. But don’t be disappointed. This shower’s peak is so broad, you can see the meteors weeks before and after. They tend to be slow and few, with a peak around 5 per hour. But this shower is known to produce a few fireballs. And really, you can look for them from the middle of September to the middle of November. The parent comet is 2P/Encke.
During the Orionids peak on the 21st, the moon is at last quarter. It will give some interference, since it’s up in the morning when Orion is high. Expect 10 to 20 meteors per hour. They move somewhat fast. The parent comet is 1P/Halley.
Other, minor, showers to try your luck with are the Draconids on the 9th, the Delta Aurigids on the 11th, the Epsilon Geminids on the 18th, and the Leonis Minorids on the 24th.
This would be a good month to get ready for November’s transit of Mercury. People in Africa will see the beginning. Viewers in South America and from Atlantic Ocean locations will see all of it. The end is visible in North America. That will be on November 11.
You must protect your eyes from the sun’s brightness and invisible radiation. Projecting an image of the sun in a pinhole viewer isn’t likely to give you something that’s both bright enough and big enough to see the black dot that is our solar system’s first planet. You can use a telescope or binoculars to project the image, but don’t do it for more than a few seconds at a time if you don’t have a filter reducing the amount of light going into the optics. If you get such a filter, make sure it’s one that is made specifically for solar viewing. That way, it’ll be safe for you to look directly through the scope.