Autumn always begins in the northern hemisphere in September.
This year it will happen at 21:54. This will mark the end of a long, hot summer as the nights cool off and become more transparent, even as they get shorter and heading for winter again.
The Autumn and Spring Equinoxes are both interesting days on Earth. They mark the only two days each year, when the sun rises exactly to the east and goes west to all but the Pole. Within a few days of the Equinoxes, the only two days of the year are exactly 12 hours for all on Earth except the Pole. The reason for this is our slightly elliptical orbit around the sun and our 23.5 degree tilt around our axis.
The days are always 1
Highlights of this month include all four brightest planets visible at the same time in the evening sky. There will also be some nice conjunctions of the moon with all these planets, but until next month no good meteor showers.
Venus is the brightest of the four and the first to set in the west about an hour after sunset. Note that at the beginning of this month, it will only be one degree to the left of Spica in the Virgin. Our sister planet is getting brighter and brighter in our skies as it keeps catching us in its orbit. We've already passed our other neighbor, Mars, but both are still much closer to Earth than usual. Venus is getting brighter, even though it's less illuminated by the sun. It will only be lit to 18 percent by the end of the month, similar to a waning crescent moon.
Then we continue east along the Ecliptic and you will encounter Jupiter in Libra, just one constellation east of Venus. Note that Venus will catch up with Jupiter later this month and close the gap to 14 degrees by the end. Jupiter has been back in the sky in its direct, eastbound movement since mid-July. So the king of the planets fades a little more as we move further ahead of him. It starts the month at 10 o'clock. and ends the month 2 hours earlier.
Jupiter is still very close to a double star in Libra with the long Arabic name Zubenelgenubi, but it slowly drifts farther away from this star, whose name means "the southern claw". Libra used to be part of Scorpius, the next star constellation in the East.
Then further east along the Ecliptic by 30 degrees, the largest gap between all four visible planets, and you will encounter Saturn in Sagittarius. His rings are still open near their maximum of 27 degrees, though it is slowly dimming, as it is now a few months after its resistance. You can easily see its biggest moon, Titan, through a telescope, and you could even see four or five more moons on a good night.
The last in this great planetary formation, which has accompanied us all summer, is Mars. The Red Planet was best in its fifteen best years last month, but it will be much brighter and bigger than usual for a few more months. It even got brighter than Jupiter last month, but Mars will be a little weaker this month and less bright again than Jupiter on July 7, as Earth is now moving further ahead of the red planet in our faster orbit around the Sun. ,  I was able to see some details on the Martian surface through several telescopes last month. I could see a few dark marks and a reference to the North and South Pole caps. I did not see any Martian atmosphere this time because of the dust winds around the world that cover much of its surface.
There will be four lunar conjunctions with the planets this month as the Moon highlights them well from these planets as they move along their designated paths along the Ecliptic. We start with the slender crescent moon that points to Venus on December 12th, then it will be on the 13th just 4 degrees north of Jupiter, then on the 17th only 2 degrees north of Saturn and eventually it will cycle 5 degrees north of Mars on the 20th The moon moves every day about 12 degrees east along the ecliptic.
I participated in the annual Stellafan Convention last month. This is the oldest and one of the biggest star parties in the world. Nearly 1,000 enthusiastic amateur astronomers participated this summer. It was held during the peak of the Perseids meteor shower and near New Moon. This is an annual pilgrimage for a diverse group of people who share a common interest. Everyone is learning new things there and sharing new experiences as they look through hundreds of large telescopes in the sky, gaining new views of our familiar skies and myriad contents as we expand our cosmic perspective, where we are all the time. 19659002] There are hands-on workshops and many great presentations for everyone. I visited some astrophotography, light pollution, variable stars and binoculars. The keynote speaker was Samuel Hale, the grandson of George Ellery Hale, the world's most famous telescope maker, who designed and built the world's four largest telescopes from 1898 to 1938.
Todd Mason also gave a great presentation. He shot the documentary "Journey to Palomar" and now creates computer graphics of the largest new telescopes in the world to show people what they look like and how they will work when they are completed. These include the Large Synoptic Survey Telescope, which will find thousands of potentially dangerous asteroids, the Giant Magellan Telescope with its seven 25-meter mirror segments and the Extremely Large Telescope with a 39-meter mirror that is nearly four times the size of the largest telescope in the world World today. They should see the first light within seven years or so, and they will probably completely revolutionize our present limited understanding of our universe.
Sept. 3: On this day in 1976, Viking 2 landed a few weeks after Viking 1 on Mars.
Sept. 9: New moon is at 2:03 pm
Sept. 12: The Moon will be near Venus tonight.
Sept. 13: The Moon will be near Jupiter tonight
Sept. 16: First quarter moon is at 19:16
Sept. 17: The moon is near Saturn tonight.
Sept. 20: The Growing Moon will be near Mars tonight. 22: Autumn starts today at 9:54 pm as the sun goes down over the celestial equator.
Sept. 23: J. Galle discovered Neptune that day in 1846. Two other astronomers calculated exactly where that planet should be based on its influence on other planets. Neptune is best in Aquarius now, but you need a telescope to see it. By 2011, 165 years after her discovery, she had created only one orbit.
Sept. 24: Full Moon is at 10:54 am This is the famous Harvest Moon because it is closest to the Equinox.
Bernie Reim of Wells is co-director of the Astronomical Society of Northern New England