Mon Sep 15, 2025 SCUTUM
The small constellation of Scutum, the “shield of Sobieski,” has no bright, or even middling-bright stars within its borders, and as it’s wedged into the summertime Milky Way, between Aquila the Eagle, Sagittarius the Archer and the Serpent’s Tail, (Serpens Cauda,) finding it is more like a process of elimination than actual discovery. It was introduced to star charts by the astronomer Johannes Hevelius to commemorate the lifting of the siege of Vienna which had happened on September 12, 1683. King Jan Sobieski of Poland led his hussars and men gathered from England, France, Germany, Austria, and even a great many displaced Tatars who had settled in Poland, in an attack that routed the Turkish army, which had lain siege to Vienna. Scutum has a few star clusters plus a planetary nebula, and even a pulsar.
Tue Sep 16, 2025 METEORITE – METEORWRONG
People bring me rocks from time to time, wanting to know if they might have found a meteorite. Before you decide to bring it in for me to look at, here are a few simple observations you can make to figure out if what you’ve got is a meteorite – or a meteorwrong. First, is the rock unusually heavy for its size? If not, then it’s probably not a meteorite. Now if it is heavy, get a magnet and see if it sticks to the rock. If not, then again, not a meteorite. Are there little holes in it, called vesicles? If yes, then it’s not a meteorite – those vesicles are usually caused by gas escaping from molten rock as it rapidly cools, and meteorites cool too slowly for that to happen. If it passes those tests, bring it in and I’ll try to help you find out if it truly is a rock from space. E-mail me at jbell@irsc.edu.
Wed Sep 17, 2025 DELPHINUS AND ARION
There are three bright stars spread out across the zenith this evening. These three stars – Vega, Altair and Deneb, form the Summer Triangle. The brightest star is Vega; it marks the constellation of Lyra the Harp. In Greek mythology, the harp was played by a musician named Arion, who was once rescued by a dolphin named Delphinus. Arion had been thrown overboard by some greedy pirates who wanted all the gold he’d won at a concert. They made him sing a song first, then they tossed him into the ocean. Now the dolphin also heard the song, and it saved him, carrying him to dry land. When the pirates arrived later, they were arrested and voted off the island. Arion’s harp is Vega and a few nearby stars, while Delphinus the dolphin is a small, faint cluster of stars on the opposite side of the Summer Triangle.
Thu Sep 18, 2025 FARTHEST NAKED-EYE OBJECT
What’s the farthest thing you can see without a telescope? Off in the northeastern sky this evening, you can find the answer to this question, but only if the skies are very clear, and very dark, and you know just where to look. It’s a small, very dim smudge of light that lies in the direction of the constellation Andromeda. But this little cloud is neither little, nor does it have any physical connection with the stars of Andromeda, which are merely trillions of miles away. It’s another galaxy, comprising hundreds of billions of stars – bigger than our own Milky Way - and it’s about 2 and a half million light years away. So if you ever catch a glimpse of this far-flung object, which we call the Andromeda galaxy, you’ll be looking at something that is 15 million trillion miles away – and that’s how far out your eye can see.
Fri Sep 19, 2025 HYPERION
On September 19, 1848, father and son astronomers William and George Bond discovered Saturn’s moon, Hyperion. To them it was just a little point of light that changed position as it orbited the ringed planet. But thanks to the Cassini spacecraft, we see it as another world. Hyperion is over 200 miles in diameter; and ordinarily such a large object should be round, but Hyperion looks pretty beat-up, covered with craters, and very irregular in shape, looking like an old meatball. Its composition is mostly water ice, with some rock and dust added for texture. Hyperion tumbles erratically as it orbits Saturn, probably owing to its irregular shape and the gravitational influence of Saturn’s biggest moon Titan. This evening you can find Saturn in the southern sky in the constellation Pisces, but Hyperion is a little too small to see without a good telescope.
