|
Maffei 1 is a giant elliptical galaxy in the constellation Cassiopeia. Once believed to be a member of the Local Group of galaxies, it is now known to belong to its own group, the IC 342/Maffei Group. It was named after Paolo Maffei, who discovered it and the neighboring Maffei 2 in 1967 via their infrared emissions. Maffei 1 is a slightly flattened core type elliptical galaxy. It has a boxy shape and is made mainly of old metal-rich stars. It has a tiny blue nucleus in which stars continue to form. Like all large ellipticals it contains a significant population of globular clusters. Maffei 1 is situated at an estimated distance of 3–4 Mpc from the Milky Way. It may be the closest giant elliptical galaxy. Maffei 1 lies in the Zone of Avoidance and is heavily obscured by the Milky Way's stars and dust. If it were not obscured, it would be one of the largest (about 3/4 the size of the full moon) brightest and best-known galaxies in the sky. It can be observed visually, using a 30–35 cm or bigger telescope under a very dark sky. ==Discovery== The Italian astronomer Paolo Maffei was one of the pioneers of infrared astronomy. In the 1950s and 60s, in order to obtain high quality images of celestial objects in the very near infrared part of the spectrum (the I-band, 680–880 nm), he used chemically hyper-sensitized standard Eastman emulsions I-N. To achieve the hyper-sensitization he immersed them in 5% ammonia solution for 3–5 minutes. This procedure increased their sensitivity by an order of magnitude. Between 1957 and 1967 Maffei observed many different objects using this technique, including globular clusters and planetary nebulae. Some of those objects were not visible at all on blue light (250–500 nm) sensitive plates.〔 The galaxy Maffei 1 was discovered on a hyper-sensitized I-N photographic plate exposed on 29 September 1967 with the Schmidt telescope at Asiago Observatory. Maffei found Maffei 1, together with its companion spiral galaxy Maffei 2, while searching for diffuse nebulae and T Tauri stars.〔 The object had an apparent size up to 50″ in the near infrared but was not visible on the corresponding blue light sensitive plate.〔 Its spectrum lacked any emission or absorption lines. Later it was shown to be radio-quiet as well. In 1970 Hyron Spinrad suggested that Maffei 1 is a nearby heavily obscured giant elliptical galaxy.〔 Maffei 1 would be among the ten brightest galaxies in the northern sky if not situated behind the Milky Way.〔 Due to the its faintness, visual observations of Maffei 1 require a telescope at least 30–35 cm in diameter, high quality sky maps and a very dark sky.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Maffei 1」の詳細全文を読む スポンサード リンク
|