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Globular Cluster NGC 104 (6th Sep 2026)

Globular Cluster NGC 104 - Located in the far southern constellation of Tucana

The concentrated light of one million stars packed into a volume of space 120 light years across makes 47 Tucanae the second brightest globular cluster in the sky, surpassed only by Omega Centauri. If Earth were placed near the centre of 47 Tucanae the collective starlight would create a nighttime as bright as day. Although it is the classic metal rich cluster, its metal abundance is still only 25% that of our sun. Metal abundance appears to have implications regarding a star’s suitability to form planets.

A concerted effort was made by the Hubble Space Telescope to search for planets within 47 Tucanae but failed to find any. The lack of planets in this compact star system supports the belief that metal poor stars in general are not conducive to planet formation.

Recent work though has astronomers reconsidering this conclusion as there may still be a strong possibility of gas-giant planets located much further out from stars in globular clusters.