M13: The Great Globular Cluster in HerculesIn 1716, English astronomer Edmond Halley noted, “This is but a little Patch, but it shews itself to the naked Eye, when the Sky is serene and the Moon absent.” Of course, M13 is now less modestly recognized as the Great Globular Cluster in Hercules, one of the brightest globular star clusters in the…Read More

Trapezium: In the Heart of OrionWhat lies in the heart of Orion? Trapezium: four bright stars, that can be found near the center of this sharp cosmic portrait. Gathered within a region about 1.5 light-years in radius, these stars dominate the core of the dense Orion Nebula Star Cluster. Ultraviolet ionizing radiation from the Trapezium stars,…Read More

Perseids from PerseusWhere are all of these meteors coming from? In terms of direction on the sky, the pointed answer is the constellation of Perseus. That is why the meteor shower that peaks tonight is known as the Perseids — the meteors all appear to come from a radiant toward Perseus. In terms of parent body, though, the sand-sized debris…Read More

Zodiacal RoadWhat’s that strange light down the road? Dust orbiting the Sun. At certain times of the year, a band of sun-reflecting dust from the inner Solar System appears prominently just after sunset — or just before sunrise — and is called zodiacal light. Although the origin of this dust is still being researched, a leading hypothesis holds…Read More

Interstellar Interloper 3I/ATLAS from HubbleDiscovered on July 1 with the NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System) survey telescope in Rio Hurtado, Chile, 3I/ATLAS is so designated as the third known interstellar object to pass through our Solar System. It follows 1I/ʻOumuamua in 2017 and the comet 2I/Borisov in 2019.…Read More