The largest body in the main belt comes to a brief standstill in the sky, visible before sunrise in Cetus the Whale.
Ceres forms a wide double with a background star in Cetus early on the morning of August 15. Credit: Alison Klesman (via TheSkyX)
- Dwarf planet Ceres exhibits apparent stationary motion at 9 P.M. EDT, but optimal observation requires morning viewing.
- At approximately 4 A.M. local daylight time, Ceres reaches an altitude of over 40° in the southern sky, located near Theta Ceti in the constellation Cetus, requiring binoculars or a telescope for visibility due to its magnitude 8.4.
- Ceres forms a visual double star with a magnitude 6.8 background star, situated 4.5’ southeast, appearing dimmer than its companion.
- This stationary point signifies a transition in Ceres’ apparent motion from prograde (eastward) to retrograde (westward), a phenomenon resulting from Earth’s orbital movement relative to Ceres.
Dwarf planet 1 Ceres is stationary at 9 P.M. EDT, though to spot it you’ll have to get up early, as it’s only visible in the morning sky.
Around 4 A.M. local daylight time, Ceres is just over 40° high in the southern sky. The main belt’s largest body is currently making its way through Cetus the Whale in a region to the lower left of Saturn, which is the brightest point light visible to the naked eye in southwestern Pisces. This morning, Ceres is not far from magnitude 3.6 Theta (θ) Ceti. At magnitude 8.4, Ceres is not visible to the naked eye; with binoculars or a telescope, you’ll want to look for the dwarf planet some 2° north-northeast of Theta Cet.
Note that today, Ceres also stands just 4.5’ southeast of a magnitude 6.8 background star, forming a wide “double star.” Ceres is the dimmer of the two.
This stopping point marks a turnaround in Ceres’ motion. Previously it was moving eastward, or prograde, relative to the background stars. Now it will begin to move westward, or retrograde. When objects appear to “stop” in our sky, their motion isn’t actually changing — instead, Earth is either passing them by or falling behind as both objects orbit the Sun.
Sunrise: 6:12 A.M.
Sunset: 7:56 P.M.
Moonrise: 11:15 P.M.
Moonset: 1:32 P.M.
Moon Phase: Waning gibbous (56%)
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40° N 90° W. The Moon’s illumination is given at 12 P.M. local time from the same location.
For a look ahead at more upcoming sky events, check out our full Sky This Week column.