Imai

HR 4656 · HIP 59747 · δ Cru

👁️ Naked-eye

📋 A written introduction is coming — for now this page shows official values only.

Star

Apparent magnitude: 2.752 mag
Parallax: 9.45 mas → about 345.1 light-years away
Spectral type: B2IV
Right ascension: 183.7863°
Declination: -58.7489°
Designation: HR 4656
Bayer designation: δ Cru
HIP number: 59747
IAU name adopted: 2018-08-10
Name language: African/ Mursi
Name origin (IAU): The Mursi name a line of four stars imai (δ Cru), thaadoi (β Cru), waar (β Cen) and sholbi (α Cen). Their successive disappearance (heliacal setting) are used to determine when the River Omo will flood (it does this several times) and hence to determine when to plant the annual crop of cowpeas beside it (after the last flood but before the ground dries out). Imai is the Mursi name for the grass that grows along the banks of the river (Rhynchelytrum repens). It is said that when the imai star disappears, the Omo rises high enough to flatten the imai grass.

Constellation

Light from this object takes about 345 years to reach Earth — the light you see tonight left around AD 1681 (official distance ÷ speed of light).
At magnitude 2.8 it is bright enough for the naked eye (limit about 6) — look from somewhere dark.
Declination -58.7° — it never rises in Seoul (37.6° N); you need to be farther south to see it.

Worked out from this object's official values.