October 8
Andromeda's Waist
Sun Position
The Sun is in Libra near -7° declination. Northern Hemisphere evening twilight ends earlier each night; Southern Hemisphere is gaining warmth and evening light simultaneously.
Sky Highlight
The Draconid meteor shower is still active on October 8, producing its final elevated rates near the radiant in Draco. This is also a fine evening for naked-eye observation of M31, the Andromeda Galaxy, which is well-placed high in the east after dark for Northern Hemisphere observers.
Deep Sky Object
M31 (Andromeda Galaxy), a spiral galaxy about 2.5 million light-years away. M31 is large enough on the sky to span roughly six times the full Moon's diameter, though only the central core is bright enough to see easily, under dark skies the full extent of the galaxy is a genuinely striking sight, a smear of ancient light arriving from 2.5 million years ago. Best for Northern Hemisphere observers in October; visible from southern latitudes but transits low.
Featured Star
Mirach (β And) is a red giant (M0IIIab) about 197 light-years away, its warm orange-red color is visible to the naked eye under dark skies. It anchors the middle of Andromeda's chain and serves as the standard hop-off point for finding both M31 and M33 by extended star-hops to the northwest and northwest-plus. Mirach, the guide to Andromeda's galaxy, haunted by a ghost in its glare.
Around This Date
- October 8, 1873The British Association for the Advancement of Science formally proposed a unified metric system for scientific measurements, an early push toward the standardization that would underpin modern astronomy.
- October 9, 1604Kepler's Supernova, a naked-eye supernova in Ophiuchus, was observed and recorded, one of only a handful of Milky Way supernovae witnessed in recorded history.
A red giant 197 light-years away can still be your navigation landmark, distance is relative to what you are trying to find.