| Emission nebula | |
|---|---|
| H II region | |
 As seen by the Legacy Survey | |
| Observation data: J2000 epoch | |
| Right ascension | 17h 46m 12s |
| Declination | −28° 51′ 0″ [1] |
| Distance | 4,890 [2] ly |
| Apparent magnitude (V) | 15.33 |
| Apparent diameter | 84' x 63' |
| Constellation | Sagittarius |
| Physical characteristics | |
| Radius | 36 ly |
| Designations | RCW 138 |
Sh 2-17 is an emission nebula in the constellation Sagittarius. It is part of the Sharpless Catalog assembled by Stewart Sharpless. It contains the infrared cluster [DB2000] 58. It is estimated to contain about 12 stars, and may cause ionization within the nebula. [3]
