A rather rare and exciting astronomical event will occur on Tuesday, Oct. 6 this year. The bright planet Jupiter will appear to disappear as the 20%-illuminated crescent moon will pass in front of it.
Astronomers call such an event an occultation, from the Latin word occultare, meaning to conceal.
On this special morning, the crescent moon will rise around 2:30 a.m. Eastern Daylight Time with Jupiter shining close by the moon’s sunlit side.
The moon will begin to cover Jupiter around 4:20 a.m. and block the giant planet for more than one hour.
Jupiter will reappear on the other side of the moon at around 5:24 a.m. [For areas in the Central time zone, these times will be an hour earlier.]
Lunar occultations of Jupiter — with only 123 visible anywhere in the world between 1980 and 2040 — are rare. But moon occultations of other planets or star clusters also occur from time to time.
However if we narrow the number of Jupiter/moon occultations for a specific location and consider only those that happen when the sun is below the horizon, one such occultation occurs on average only once every 13 years.
The next good dark sky occultation of Jupiter for most of North America will be in November 2037.
Even though occultations have little scientific value, they are memorable eye-catching events.
So set your alarm for early morning on Oct. 6 so as not to miss this spectacular event.
The other big event this month happens on Sunday, Oct. 4 when Saturn reaches opposition, being positioned opposite the sun in the sky from our point of view on Earth. Saturn rises in the east as the sun sets in the west.
Saturn for the next few months will be at its brightest and best appearance for all of 2026.
Saturn will be prominent in the eastern evening sky among the dim stars of Pisces, and just below Pegasus.
Mars is now rising in the eastern sky around 1 a.m. among the stars of Cancer the crab.
The Beehive open star cluster [M44] is also in Cancer, and on the morning of Oct. 5 the waning crescent moon will appear near the top of this cluster, making a lovely view with binoculars. Mars will be found just to the right [west] of this cluster.
On Oct. 11, Mars itself may be seen right in the middle of the cluster, and making again another great binocular sight.
On Oct. 30, Mars will have moved into Leo where it will be found quite close to brighter Jupiter.
Jupiter itself brightens considerably in October, and telescopic views of it before dawn will get better and better throughout the month. The planet outshines Leo’s brightest star, Regulus, which is found at the bottom of the “backward” question mark shape forming the front of the constellation.
October’s full moon is on the 26th.