Struve 747 (Σ747)

Struve 747 (Σ747) is a double star in the constellation Orion, magnitude 4.7.

A wide, easy pair of blue-white stars in Orion’s sword, about half a degree south of the Orion Nebula and 8′ southwest of Iota Orionis. Its components (magnitudes 4.7 and 5.5; spectral types B0.5 V (blue-white) and B1 V (blue-white)) lie 35.3″ apart at PA 224° (measured 2021).

When and where to see it

It is best placed in the evening sky around January, when it crosses the meridian at about 10 pm local time (around midnight in December). It can be seen from everywhere south of 84°N and never sets south of 84°S.

At its highest it stands 34° up from 50°N, 49° up from 35°N, 84° up from the equator, 61° up from 35°S.

Facts

Type

Double star

Constellation

Orion

Designations

Σ747, Σ 747, STF 747, HIP 26199

Magnitude

4.7

Position

RA 5h 35.0m, Dec −6° 0′ (J2000)

Open AstroPilot to see when Struve 747 (Σ747) is highest tonight from your location, how easy it is with your telescope or binoculars, and an eyepiece view.