Deep in the Southern sky, right next to the Small Magellanic Cloud and just 18° from the South Celestial Pole, lies this magnificent globular cluster.
With millions of stars, 47-Tucanae is the second largest globular cluster in the sky after Omega Centauri. Its brightest stars are around 11th magnitude but despite this, the overall magnitude of about +4 makes it a fairly easy object to spot as a fuzzy object in a dark sky – provided you are situated south of latitude 18 North!
The Northern Hemisphere has its attractions, such as M31, which is so low here in Sydney. However, we are well situated here in the South to see the two brightest globular clusters – 47 Tucanae, Omega Centauri – and both Magellanic Clouds.
This 51 minute image was shot from my home in surburbia .
Daylight saving arrived today, meaning observing sessions will be cut short.
They will at least be warmer than the field trips we’ve experienced over the winter months, where the minimum dropped to between zero and -5° C.
Designation: 47-Tucanae, NGC 104, Caldwell 106.
Visual magnitude: +3.95
Apparent size: 50′
Diameter: 213 light years.
Distance: 15,000 light years.
Altitude during exposure: 48° above southern horizon.
Also in image: NGC 121, a more distant globular cluster (left, bottom ). Astrometry.net
Exposure: 35 x 88 sec = 51 min.
Image acquisition: SharpCap.
|Telescope:||SkyWatcher Esprit||Type:||120ED triplet refractor|
|Focal:||840 mm F/7||Mount:||SkyWatcher EQ6-R Pro|
|Camera:||ZWO ASI 071 MC Pro||Type:||CMOS 28.4mm 16 Mpx
|Optical aids:||Flattener: Y; filter: LP||Guiding:||Yes|
|Polar aligning:||QHYCCD PoleMaster||Polar Error:||60”|
[ZWO ASI071MC Pro]
Image © Roger Powell