This is the last full month of autumn as nature prepares for winter once again in the northern hemisphere. The nights are getting colder and longer, but it will be well worth your effort to partake in some of its treasures. This month may not be quite as rich as last month was with Mars becoming a real star, but this November still has more to offer than most other Novembers.

The highlights include Mars just past its best but still much better than usual, Mercury and Venus in the morning sky all month, Jupiter rapidly catching up with Saturn, the usual conjunctions of the moon with different planets, and three meteor showers including the Leonids. The month also will feature a partial penumbral lunar eclipse since we are entering another eclipse season, and the Gegenschein, or counter glow, visible around midnight high in the sky as a faintly glowing band of light marking the spot directly opposite in our sky.

Since we have now raced past Mars in our speedy orbits around the sun, the red planet will shrink in our rear-view as quickly as it got bigger and brighter. It will become more than twice as faint by the end of this month as it was starting this month. Mars is not as fast as we are, but it is still racing right along at 15 miles per second compared to our own 18.6 miles per second.

Mercury makes its best appearance for the year in the morning sky all month long. Our first planet is at greatest western elongation from the sun on Nov. 10 at 19 degrees. It will rise 90 minutes before sunrise that day. Mercury is still over 100 times fainter than nearby Venus, but Mercury will get brighter throughout this month.

In a telescope you will notice a thin crescent early in the month and then you can watch it getting more illuminated by the sun as time goes by. We just launched a new mission to Mercury two years ago due to arrive in five more years, named BepiColombo, in honor of the Italian-American mathematician and engineer who first discovered the best way to get to this planet, which is much more difficult than you may think because of its proximity to the sun’s enormously powerful gravitational field. This is a joint mission of the European Space Agency and Japan Aerospace Exploration Agency and is actually three well-designed spacecraft in one.

Mercury is only about 60 million miles away, but it takes seven years to get there, as long as it takes to get all the way out to Saturn, which is nearly 1 billion miles away. So BepiColombo has to make several flybys of the earth and Venus first and then many more flybys of Mercury as it slowly spirals inward to be in position to safely orbit around just Mercury and not the whole inner solar system.

Mercury is the least explored terrestrial planet, we have only been there twice, with Mariner 10 in 1974 and Messenger in 2011 to 2015, and we have never soft-landed on the planet. We allowed Messenger to crash into Mercury in 2015 after it ran out of fuel, thereby creating a 50-foot-wide crater. We discovered many new things about Mercury including that it has water ice near its poles, a giant core that is 85 percent of its volume, compared to earth’s core at only 15 percent, and that it has a strange and offset magnetic field. It also has very little surface geological activity, unlike Mars. We have launched 49 missions to Mars already, including three this year. However, our success rate is not good with Mars since about one-third of those expensive missions have failed.

Mercury is a very strange place already and it is only getting stranger the more details we learn about it. One day on Mercury lasts 59 earth days and one year only lasts 88 earth days. It orbits around the sun almost twice as fast as we do and it spins very slowly, at only 7 mph, which is jogging speed. It is only 3,000 miles in diameter, smaller than two moons in our solar system, Ganymede around Jupiter and Titan around Saturn. Mercury experiences the greatest temperature differences of any planet in our solar system. Since it has no atmosphere, it reaches 800 degrees on the side facing the sun and 300 degrees below zero on the other side.

Venus still rises around 3 a.m. and can be seen near Spica in Virgo and about 15 degrees above Mercury. Venus is also a very strange planet that actually spins in retrograde about twice as slowly as Mercury spins on its axis. One day on Venus is 243 earth days and one year is 225 earth days, so its day is even longer than its year. Neither of these two planets has any moons because of the sun’s strong gravitational field. That field causes the entire orbit of Mercury to change a little (0.43 degrees per century), each time it rapidly orbits the sun.

Watch the waning crescent moon pass near Venus and then Mercury half an hour before sunrise on the mornings of Nov. 12 and Nov. 13. Spica in Virgo will also be nearby.

Jupiter and Saturn start the month just over 5 degrees apart and they will end the month just over 2 degrees apart. The faster-moving Jupiter is approaching Saturn at the rate of a degree and a half every 2 weeks or a tenth of a degree every day. Then keep watching into next month when Jupiter will get to within just one tenth of a degree of Saturn, their closest approach in over 400 years, since the invention of the telescope. Watch the waxing crescent moon drift by these two gas giants on Nov. 18 and Nov. 19.

The three meteor showers are the Southern Taurids, peaking in late October near the full moon, the Northern Taurids peaking on the Nov. 11, and the Leonids peaking on the morning of Nov. 18. Both of the Taurid showers will appear to emanate from Taurus near the Pleiades and they are both caused by Comet Encke, which orbits the sun every 3.3 years. The Leonids should be better than those two, but even though there will be no moon you can only expect about 15 meteors per hour unless the parent comet, Tempel-Tuttle is near the sun, which only happens every 33 years.

I was lucky enough to see the last great outbreak of this shower back in 2001 when I saw nearly 1,000 meteors per hour for about three hours that morning from our newly built observatory in Kennebunk. I also saw about 15 fireballs that memorable night, several of which lasted so long that some other meteors were passing right through their extended and twisting dust trails high in our atmosphere. I even saw the zodiacal light for the time that morning several hours before sunrise. It looked like a faintly glowing pyramid or haystack of light extending about 15 degrees into the sky along the ecliptic. It is best seen now in the morning sky and again in March in the evening sky soon after sunset.

A related event can also been seen this month starting near midnight. That is the Gegenschein, which is the German word for counter glow. That marks the antisolar point in the sky, directly opposite of where the sun is at that time. It looks like a faint glow along the highest part of the ecliptic. It is caused by the same thing that causes the zodiacal light, which is the sunlight reflecting off all the scattered comet and asteroid dust forming a complete torus all around the ecliptic. Look for it during the middle of this month from a dark sky site when there will be no moon to interfere.

Then we are entering an eclipse season again. That will create another partial penumbral lunar eclipse during this full moon on Nov. 30 as 83 percent of the moon will pass through the earth’s penumbral shadow. The last one was on July 5 when only 36 percent of the moon passed through our shadow. The one this month will peak at 4:45 a.m. and you should be able to notice the slight shading, especially through a camera or a pair of binoculars. This will be the last of four penumbral lunar eclipses in a row. We will have two total lunar eclipses next year. This eclipse season will also lead to a great total solar eclipse over Chile and Argentina on Dec. 14.

NOVEMBER HIGHLIGHTS

Nov. 1: Daylight saving time ends at 2 a.m.

Nov. 3: In 1957 the Soviet Union launched Sputnik 2.

Nov. 6: In 1572 Tycho Brahe discovered a supernova in Cassiopeia without a telescope.

Nov. 8: Edmund Halley was born in 1656. I first saw his comet on this day in 1985. Last quarter moon is at 8:47 a.m.

Nov.9: Carl Sagan was born in 1934.

Nov. 13: The slender waning crescent moon can be seen near Spica, Venus, and Mercury half an hour before sunrise.

Nov. 15: New moon is at 12:08 a.m.

Nov. 17: The Leonid Meteor Shower peaks this morning into the 18th.

Nov. 21: First quarter moon is at 11:46 p.m.

Nov. 30: Full moon is at 4:31 a.m. This is the Frosty or Beaver Moon. There will be a partial penumbral lunar eclipse this morning visible for us and most of this country.

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