Wings of gas and dust

Credit: NASA, ESA, N. Smith (Uni­ver­sity of Cal­i­for­nia, Berke­ley), and The Hub­ble Her­itage Team (STScI/AURA)

Giant bird shapes seem to abound within the glow­ing gas of the Carina Neb­ula. Mon­day we found a stel­lar swift. Today, it looks like a swan, or pel­i­can, or eagle.

In this part of the image from NASA’s Hub­ble Space Tele­scope, we find the most intense part of the star form­ing neb­ula. We also find in the area one of the most mas­sive stars in the galaxy, Eta Cari­nae, just to the left of cen­ter in the image. It is a blue hyper­giant star and it is very bright. Astronomers guess that Eta Cari­nae is 100 to 150 times more mas­sive than our Sun and four mil­lion times more lumi­nous. Although it is labeled as the sev­enth bright­est star in the con­stel­la­tion Carina, the light from the star changes year to year. Some­times it becomes very bright and then becomes very dim, so dim we can­not see it from Earth. In 1841, an out­burst occurred that made the star the sec­ond bright­est object in Earth’s night sky. The mate­r­ial thrown off the star cre­ated the Homuncu­lus Neb­ula, which in Latin means “lit­tle man.” It looks like a dou­ble bub­ble around Eta Cari­nae. Hyper­giant stars like Eta Cari­nae quickly end their lives in a super­nova explo­sion. Eta Carina was known to ancient men who called it Fora­men. Chi­nese astronomers refer to it as Tseen She, or Heaven’s Altars.

The whole Carina Neb­ula likely would have looked dif­fer­ent if the Hub­ble Space Tele­scope had been in orbit before 1841. Ultra­vi­o­let radi­a­tion from the out­burst would have lit up the entire neb­ula, caus­ing it to glow more brightly than before.

The Carina Neb­ula is a very large neb­ula in Earth’s skies but it lies far in the south­ern hemi­sphere so it’s not well known. Astronomer Nico­las Louis de Lacaille dis­cov­ered the neb­ula in 1751–52 dur­ing a sci­ence trip to the Cape of Good Hope at the tip of Africa.

The Carina Neb­ula is about 7,500 light-years away toward the con­stel­la­tion Carina the Keel. Carina is a con­stel­la­tion in the south­ern hemi­sphere. it is part of an older con­stel­la­tion group called Argo Navis, after the ship that car­ried Jason and the Arg­onauts.