789 Lena
Encyclopedia
789 Lena is a medium-sized X-type asteroid
orbiting in the Main belt near the Eunomia family
. However, true family members have an S-type
composition, so it is almost certainly an unrelated interloper. Lena has an unusual lightcurve, which indicates that
it is either a very slow rotator (with period well over 22 hours), very irregular shaped, or both.
X-type asteroid
The X-group of asteroids collects together several types with similar spectra, but probably quite different compositions.-Tholen classification:In the Tholen classification the X-group contains the types:* E-type* M-type, the largest grouping* P-type...
orbiting in the Main belt near the Eunomia family
Eunomia family
The Eunomia family of asteroids is a large grouping of S-type asteroids named after the Greek goddess Eunomia. It is the most prominent family in the intermediate main belt...
. However, true family members have an S-type
S-type asteroid
S-type asteroids are of a stony composition, hence the name. Approximately 17% of asteroids are of this type, making it the second most common after the C-type.-Characteristics:...
composition, so it is almost certainly an unrelated interloper. Lena has an unusual lightcurve, which indicates that
it is either a very slow rotator (with period well over 22 hours), very irregular shaped, or both.