DORADO pronounced doh-RAH-doh
This constellation representing the Goldfish or Swordfish, was introduced by the German celestial cartographer Johann Bayer in his famous sky atlas Uranometria in 1603. The constellation came from the vivid imagination of the Dutch explorer Pieter Dircksz Keyser, who noted them on a voyage to the East Indies (now Indonesia) in 1596.
To find Dorado look south in the late summer evening sky, and find Achernar and Canopus. (The Southern Cross points towards Achernar). Look for the cloudy patch like a detached part of the Milky Way between, and slightly lower than, them. This cloudy patch is the Large Magellanic Cloud. The Smaller Cloud is below Achernar.
The chart shows the sky looking a little east of south at about 11.30 pm (NZDT) in mid December
Details of some of the objects shown in the chart.
α Doradus is a magnitude 3.3 blue-white star about 190 light years away.
β Dor is yellow super-giant about 7,500 light years away. This star is one of the brightest Cepheid variable stars pulsating between magnitudes 3.8 and 4.7 every 9 days and 20 hours.
The most famous object in Dorado is the Large Magellanic Cloud. This satellite companion galaxy to our own Milky Way is easily visible to the unaided eye from a dark sky site on a moonless night as a cloudy patch. This irregular spiral galaxy is around 180,000 light years away, but binoculars and telescopes show individual bright stars, fuzzy nebula and clusters. The cloud also extends into part of the constellation of Mensa.
NGC 2070 the celebrated Tarantula Nebula is a looping cloud of hydrogen gas about 1000 light years in diameter in the Large Cloud that appears to the unaided eye as a fuzzy star, also known as 30 Doradus. Through a telescope the spider like shape becomes apparent. At the centre of the nebula is a cluster of bright supergiant stars whose ultra-violet output makes the nebula glow. The Tarantula Nebula is larger and brighter than any other nebula in the Milky Way. If it were at the distance of the Orion nebula, the Tarantula would fill the entire constellation of Orion and would cast shadows.
Dorado is highest in the sky to the south between 10 and 11 pm NZDT in mid January. The constellation is far enough south to be circumpolar for much of New Zealand, only the most northerly part briefly sets as seen from Auckland.