About NGC 6531 (M21)

NGC 6531 is a rewarding deep-sky target and is visible as a compact luminous region. It has moderate brightness.

Current visibility

It is currently below the horizon.

It stays above 30° for roughly 8 hours.

Observing conditions matter, subtle features are easily lost in bright skies.

Observing tips

It can be challenging under typical skies.

What to expect

At higher magnification, subtle detail can be detected.

Type

Open Cluster

Constellation

Sagittarius

Distance

4250 ly

Size

13.0'

Season

Summer

Difficulty

Moderate

Magnitude

6.5