A little ramble through Puppis the Stern

This is the largest of the four sections into which the ancient constellation of Argo Navis, the ship of the Argonauts, the constellation was dismembered in the 1750s by the French astronomer Nicolas Lacaille. The other sections are Carina the Keel, Pyxis the compass and Vela the sails.

Puppis lies in the Milky Way and contains rich star fields which can be seen with binoculars. From Britain Puppis is very low in the sky and is difficult to make out any stars, this is a winter constellation.

As this was once part of the constellation of Argo Navis, there is no alpha star. Zeta is the brightest star whose name is Naos which means ‘ship’ has a magnitude of 2.2 with a surface temperature of a whopping 38,000’C. It’s an 0 class star and is 1,080 light years away. It will become a supernova in the future.

Pi the second brightest star, its name Ahadi which means ‘having much promise’ has a magnitude of 2.7 and is a K class supergiant with a temperature of 3,700’C and is 810 light years away.

Rho magnitude 2.8 is an F class supergiant with a temperature of 6,700’C lying at a distance of 65 light years. Rho has no name attached to it.,

Tau magnitude 2.9, an orange K class giant with a temperature of 3,800’C and is 182 light years away.

One of the brightest novae of seen in modern times. Nova Puppis 1942 was seen by Bernhard Dawson in Argentina on November 8th, 1942, When discovered it was about magnitude 5.0 but the following day it reached magnitude -0.2 It rapidly faded below naked eye visibility by the end of November. Nova Puppis lies at a distance of around 3,700 light years.

M46 open cluster discovered by Messier in 1771 John Herschel called it superb while Admiral Smythe recorded it as a ‘noble though loose assemblage of stars. M46 is mag 6.1 and lies 5,000 light years away and contains around 500 stars. Its age is around 250 million years old.

M47 open cluster discovered by Messier in 1771 it was regarded for a long time as one of Messier’ missing objects owing to the position given by Messier. It now seems almost certain that NGC 2422 is indeed M46. This discovery was only made in 1959. It lies very close to M46 and shines with a magnitude of 4.2 it lies 1,600 light years away and is 78 million years old. M46 contains around 500 stars.

M93 open cluster discovered by Messier in 1781 Admiral Smythe described it as ‘a neat group of a star fish shape. Caroline Herschel, sister of William independently discovered it in 1783 not realising the Messier had already seen it. Its magnitude is 6.2 and is about 3,400 light years away.

NGC 2451 is a bright open cluster with about 40 stars. It shines with a magnitude of 3.0 and is centred around the star c Puppis which has a magnitude of 3.6. It was not seen by Messier because it was too far south for him. NGC 2451 is 850 light years a\way which is quite close.

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