what are its characteristics?
Irregular in shape and its tail has been shortened to make space for this last constellation he had drawn up.
Characteristics
Irregular in shape, Hydrus is bordered by Mensa to the southeast, Eridanus to the east, Horologium and Reticulum to the northeast, Phoenix to the north, Tucana to the northwest and west, and Octans to the south; Lacaille had shortened Hydrus' tail to make space for this last constellation he had drawn up.
what is hydrus? Small constellation in the deep southern sky.
Covering 243 square degrees and 0.589% of the night sky, it ranks 61st of the 88 constellations in size. Irregular in shape, it covers 243 square degrees and 0.589% of the night sky; it ranks 61st of the 88 constellations in size ; Hydrus culminates at midnight around 26 October. Covering 243 square degrees and 0.589% of the night sky, it ranks 61st of the 88 constellations in size
Hydrus Hydrus Hydrus
Characteristics Characteristics Characteristics
 Covering 243 square degrees and 0.589% of the night sky, it ranks 61st of the 88 constellations in size.  Irregular in shape, Hydrus is bordered by Mensa to the southeast, Eridanus to the east, Horologium and Reticulum to the northeast, Phoenix to the north, Tucana to the northwest and west, and Octans to the south; Lacaille had shortened Hydrus' tail to make space for this last constellation he had drawn up. Covering 243 square degrees and 0.589% of the night sky, it ranks 61st of the 88 constellations in size. The three-letter abbreviation for the constellation, as adopted by the International Astronomical Union in 1922, is "Hyi". The official constellation boundaries, as set by Belgian astronomer Eugène Delporte in 1930, are defined by a polygon of 12 segments. In the equatorial coordinate system, the right ascension coordinates of these borders lie between and , while the declination coordinates are between −57.85° and −82.06°. As one of the deep southern constellations, it remains below the horizon at latitudes north of the 30th parallel in the Northern Hemisphere, and is circumpolar  Covering 243 square degrees and 0.589% of the night sky, it ranks 61st of the 88 constellations in size. 
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Hydrus [SEP] Characteristics
Irregular in shape, Hydrus is bordered by Mensa to the southeast, Eridanus to the east, Horologium and Reticulum to the northeast, Phoenix to the north, Tucana to the northwest and west, and Octans to the south; Lacaille had shortened Hydrus' tail to make space for this last constellation he had drawn up. Covering 243 square degrees and 0.589% of the night sky, it ranks 61st of the 88 constellations in size. The three-letter abbreviation for the constellation, as adopted by the International Astronomical Union in 1922, is "Hyi". The official constellation boundaries, as set by Belgian astronomer Eugène Delporte in 1930, are defined by a polygon of 12 segments.