The Nu Eridanids meteor shower
Key facts
- Peak
- around 10–11 September
- Active
- late August to mid-September
- Rate at peak (ZHR)
- low (detected mainly by video)
- Speed
- about 67 km/s
- Radiant
- Eridanus (near the star Nu Eridani, west of Orion)
- Parent body
- Unknown; probably a long-period comet
Dates shift slightly from year to year. This year's peak is in the events calendar.
The Nu Eridanids are a fast September shower radiating from the northern end of Eridanus, just west of Orion. They were picked out by video cameras in Japan and have since been confirmed by other networks.
Discovery. The shower was one of eleven announced in 2009 by Takashi Kanamori of Tokyo, from two years of video recordings at several Japanese sites. Measured orbits revealed a compact group of fast meteors in September from near Nu Eridani.
The radiant. Eridanus, the River, is a long, winding constellation that starts beside Rigel, Orion's bright blue foot, and meanders far into the southern sky. The radiant is near its northern end, close to the celestial equator. In September this part of the sky rises in the late evening and is high in the south before dawn.
The meteors. At about 67 kilometres per second, Nu Eridanids are among the fastest shower meteors. Such speeds mean the meteoroids meet Earth almost head on, typical of debris from long-period comets on steeply tilted orbits. No parent has been identified. Studies of the orbits suggest a long-period comet that has not yet been discovered.
What to expect. A few fast meteors an hour at most, mostly faint and quick. September mornings also bring the September Epsilon Perseids and many sporadic meteors, so careful observation of direction is needed.
Viewing from the UK. The radiant is well placed in the hours before dawn. September nights are dark and usually still mild.
Viewing worldwide. Because the radiant is near the celestial equator, it can be seen from both hemispheres, and tropical observers have it high before dawn.
Viewing tips
- Watch in the hours before dawn, when Orion and Eridanus are rising high.
- Find Rigel, then look west to the start of the River.
- Expect very fast, short meteors.
- Plot meteors on a chart to separate them from September Epsilon Perseids.
- Use a camera, which records faint members better than the eye.