Minor Planet (1) Ceres

Royal Astronomical Society of New Zealand

The Brighter Asteroids in 2008: (1) Ceres

Charts showing the path of Ceres during 2008 and early 2009. Ceres is too close to the Sun for observation during June and July.

January to March April and May August and September October and November End of 2008

Positions of Ceres in 2008 Other Asteroids

Ceres does not reach an opposition position during 2008, the next one being on 2 March 2009. The asteroid is at conjunction with the Sun on 28 June 2008, and too close to the Sun for observation about a month either side of this date.

On 1 January 2008, Ceres will be at a stationary point in Cetus. In the days that follow, Ceres will start moving forward to the east and crosses into Aries on January 11. It swings across a corner of this constellation to enter Taurus on March 9. As it crosses Taurus it will pass under 5° from the Pleiades at the end of March and be just under 6° from Aldebaran, the brightest star in Taurus, on April 23. Ceres will still be in Taurus when it becomes lost in evening twilight late in May. On 22 May it will be less than half a degree from Mercury, but both will be very low and difficult to see in the evening twilight.

When Ceres emerges from the Sun into the morning sky, at the beginning of August, it will be in Gemini, about 3° from β Gem, the brightest star in the constellation. Both will be very low and difficult to see in the morning twilight. Ceres moves on into Cancer on 13 August and then into Leo on 27 September where it remains for the rest of the year. It will gradually rise earlier but remain a morning object for the rest of 2008. By December 31 it will rise soon after 1 am, NZDT.

As its number implies, Ceres was the first Minor Planet or Asteroid to be discovered. It was discovered by G Piazzi at Palermo in Sicily being first seen by him on 1 January 1801.

Ceres has a diameter of 932.6 km and is easily the largest inner asteroid, although recently a number of larger Kuiper belt objects have been discovered. At its 2006 meeting in Prague, the IAU voted that Ceres should be one of the group of "Dwarf Planets". It is the only asteroid that is large enough to be pulled into a spherical shape by its gravity.

Ceres's orbital period is 4.60 years, its distance from the Sun varying between 2.55 and 2.98 AU. The orbit is inclined at 10.6° to the ecliptic.

RASNZ home page

Chart showing the path of Ceres from January to March 2008.

The chart is a southern hemisphere view with north at the bottom and east to the right. Stars to magnitude 9.0 are shown, which is about the limiting magnitude of 50 mm aperture binoculars. Magnitudes are marked (without a decimal point) for stars brighter than 6.5.