Mon Sep 22, 2025 FIRST DAY OF AUTUMN
Today at 2:19 pm Eastern Daylight Time, fall will begin. This is the autumnal equinox, a point in time when, if you’re at the earth’s equator, the sun can be seen at the zenith, the top of the sky, at noon. Today, everyone around most of the world enjoys days and nights of pretty much equal length, hence the term “equinox,” which means “equal night”. From now until after the beginning of winter the sun will rise to the south of east and set to the south of west, and its noontime altitude will continue to decrease as well. The 23½ degree tilt of the earth’s axis causes the sun’s path across our sky to drift lower and lower at noon as we move toward winter. But folks who live below the equator are observing the beginning of spring: the seasons are reversed for earth’s southern hemisphere.
Tue Sep 23, 2025 NEPTUNE’S DISCOVERY
Neptune was discovered on September 23rd, 1846. Johanne Galle used the Berlin Observatory’s nine-inch refracting telescope to search for a possible eighth planet in a small spot in the sky where the mathematician Urbain Leverrier had calculated it to be. Searching that spot, Galle saw a tiny, faint blue dot in the telescope’s eyepiece. Galle and his assistant Heinrich d’Arrest opened up their book of star maps, something called, the Berliner Akademischen Sternkarte, (I think I said that right,) and found that his star was “not on the map!” The next night they found that the tiny dot had moved against the background of fixed stars - it was a wanderer, a planet. Tonight, Neptune will be in the southeast after sunset, very close in position to the planet Saturn – but you’ll need a good telescope to find it!
Wed Sep 24, 2025 PLANETARIUM: ALWAYS ABOVE/SEARCHING FOR SATELLITES
The first man-made satellite was launched from the Soviet Union in 1957. A few months later, America’s Explorer 1 satellite discovered the Van Allen radiation belts that surround our planet. Since then, thousands of satellites have found their way to orbit our earth. With all of them up there, somebody has to keep track of them, and that’s why the United States Space Force was created. Its motto, Semper Supra, or Always Above, is the title of our newest sky show, which will be presented this Friday night and Saturday afternoon at the Hallstrom Planetarium. We’ll talk about these satellites, and I will even show you how to watch for them yourselves in the hours before dawn or after sunset. Call 772 462 4750 to get tickets to “Always Above!”
Thu Sep 25, 2025 NAME THAT CONSTELLATION - SEPTEMBER
Can you identify the twenty-ninth largest constellation? It is bordered on the north by Serpens Caput and Virgo; on the east by Scorpius and Ophiuchus; on the south by Hydra and Lupus; and on the west by Virgo again. This constellation was created by the Romans about 21 hundred years ago when they formed it from the claws of Scorpius, and they often portrayed it as being held by Virgo, who represented Astraea, goddess of Justice. This constellation has no notable deep sky objects like galaxies or nebulas, but tonight the crescent moon appears below its brightest star Zubenelgenubi, which means “southern claw.” Can you name this star figure, the seventh constellation of the zodiac, and the only zodiacal figure that is not a person or an animal? The answer is Libra the Scales, now visible in the southwest sky after sunset.
Fri Sep 26, 2025 PLANETARIUM: ALWAYS ABOVE/SEARCHING FOR SATELLITES
The first man-made satellite was launched from the Soviet Union in 1957. A few months later, America’s Explorer 1 satellite discovered the Van Allen radiation belts that surround our planet. Since then, thousands of satellites have found their way to orbit our earth. With all of them up there, somebody has to keep track of them, and that’s why the United States Space Force was created. Its motto, Semper Supra, or Always Above, is the title of our newest sky show, which will be presented this Friday night and Saturday afternoon at the Hallstrom Planetarium. We’ll talk about these satellites, and I will even show you how to watch for them yourselves in the hours before dawn or after sunset. Call 772 462 4750 to get tickets to “Always Above!”
