The Giant and the Dwarf - 47 Tuc & NGC 121 (Massimo Di Fusco)

The Giant and the Dwarf - 47 Tuc & NGC 121

47 Tucanae or 47 Tuc (also designated as NGC 104 and Caldwell 106) is a globular cluster located in the constellation Tucana. It is about 15000 light-year from Earth and 120 light years in diameter. Due to its far southern location, 18° from the south celestial pole, it was not catalogued by European astronomers until the 1750s, when the cluster was first identified by Nicolas-Louis de Lacaille from South Africa.
47 Tucanae is the second brightest globular cluster in the sky (after Omega Centauri), and is noted for having a small very bright and dense core. It is one of the most massive globular clusters in the Galaxy, containing millions of stars. The cluster appears roughly the size of the full moon in the sky under ideal conditions.
It is not yet clear whether 47 Tucanae hosts a central black hole. Hubble Space Telescope data constrain the mass of any possible black hole at the cluster's center to be less than approximately 1500 solar masses. However, in February, 2017, astronomers announced that a black hole of some 2200 solar masses may be located in the cluster; the researchers detected the black hole's signature from the motions and distributions of pulsars in the cluster. However, a recent analysis of an updated and more extensive timing data set on these pulsars provides no solid evidence in favor of the existence of a black hole.

NGC 121 is the oldest globular cluster in the Small Magellanic Cloud, which is a dwarf satellite galaxy of the Milky Way. This cluster was first discovered by English astronomer John Herschel on September 20, 1835. The compiler of the New General Catalogue, Danish astronomer John Louis Emil Dreyer, described this object as "pretty bright, pretty small, little extended, very gradually brighter middle". The cluster is located at a distance of around 200000 light-year from the Sun.

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Deep sky
Solar system
Extremely wide field
Star trails
Northern lights
Noctilucent clouds
Landscape
Artificial satellite

	Image of the day	Top pick	Top pick nominations	Total submitted
Backyard
Traveller
Own remote observatory
Amateur hosting facility
Public amaeteur data
Professional, scientific grade data
Mix of multiple sources
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Unknown

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Status	Advanced success
Started	...
PixInsight job	XHVGSMGCWN244YKJ3YB1N3HIXMK9HQR5
PixInsight queue size	n/a
PixInsight stage	TASK_LOG

RA (center)	00h24m38s.732
RA (top/left)	00h30m28s.676
RA (top/right)	00h18m58s.543
RA (bottom/right)	00h18m29s.809
RA (bottom/left)	00h30m36s.777

Dec (center)	-71°58′58″.60
Dec (top/left)	-71°30′07″.41
Dec (top/right)	-71°29′21″.82
Dec (bottom/right)	-72°27′08″.46
Dec (bottom/left)	-72°27′55″.99

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