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Dwarf planet Ceres passes close to a background star in Cetus tonight, creating a temporary, one-night-only “double star.”
Ceres remains close to Iota Ceti all month, tracing out a path that should be relatively easy to follow. Credit: Astronomy: Roen Kelly
The article details an observation opportunity for dwarf planet 1 Ceres, which will appear at 9th magnitude within the constellation Cetus.
Ceres will form a temporary optical double system with a background star, observable around 8 P.M. local time.
Specific navigational instructions are provided, locating Ceres 4.4° northeast of Iota Ceti and 2 arcminutes north of the 7th-magnitude star HD 3126 (HIP 2710).
Accompanying astronomical data includes sunrise, sunset, moonrise, moonset times, and the Moon’s phase as a 24% waxing crescent for a specified location.
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Dominating the main belt, dwarf planet 1 Ceres now shines at 9th magnitude in Cetus the Whale. The small dot is passing close to a background star this evening, appearing as one component in a temporary double system you can enjoy for one night only.
Ceres is located about 4.4° northeast of magnitude 3.6 Iota (ι) Ceti, which itself stands to the upper right of brighter magnitude 2.0 Diphda (Beta [β] Cet) in the south around 8 P.M. local time. Once you’ve found Iota, skim slowly northeast with binoculars or a telescope, looking for a 7th-magnitude star. This is HD 3126 (also cataloged as HIP 2710) — it may even be in your go-to scope’s stellar library, allowing you to zoom right over with the push of a button. Once there, Ceres is the fainter spot just 2’ north of this star.
Sunrise: 7:20 A.M.
Sunset: 4:40 P.M.
Moonrise: 10:29 A.M.
Moonset: 9:17 P.M.
Moon Phase: Waxing crescent (24%)
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40° N 90° W. The Moon’s illumination is given at 10 P.M. local time from the same location.