BBG

BBG may refer to:

USS Kentucky (BB-66)

USSKentucky (BB-66) was an uncompleted battleship originally intended to be the sixth and final member of the Iowa class constructed for the United States Navy. At the time of her construction she was the second ship of the United States Navy to be named in honor of the U.S. state of Kentucky. Hull BB-66 was originally to be the second ship of the Montana class. However, the U.S. Navy's experiences in World War II led it to conclude that it required more fast battleships to escort the new Essex-class aircraft carriers that were being built. As a result, Kentucky was reordered as an Iowa-class battleship midway through the war. Like her sister ship Illinois, Kentucky was still under construction at the end of hostilities and was caught up in the post-war draw-down of the armed services. Her construction was suspended twice, during which times she served as a spare parts cache of sorts. In the 1950s, there were several proposals to complete the ship as a guided missile battleship. These were abandoned primarily due to cost concerns, and Kentucky ultimately was sold for scrap in 1958.

HUDF-JD2

HUDF-JD2 (UDF 033238.7 -274839.8 or BBG 3179) is a distant, massive, post-starburst galaxy that was discovered with the Hubble Ultra Deep Field (HUDF) image. It was the most distant galaxy identified in the HUDF, in 2005. It is located at 03^h 32^m 38.7268^s−27° 48′ 39.885″ in the constellation of Fornax.

In a 2005 search for very red galaxies in the HUDF that were not detected at wavelengths shorter than the near-infrared J band, two objects were detected. The second, initially designated UDF033238.7-274839.8, displayed a high redshift and showed characteristics of a post-starburst galaxy. The derived photometric redshift yielded z approximately equal to 6.5, which indicates it is most likely being viewed from a time when the Universe was only 830 million years old. The estimated bolometric luminosity of this galaxy is a trillion (10¹²) times the solar luminosity (the luminosity of the Sun) and it has a mass of approximately 6 × 10¹¹solar masses.

The spectrum of this object indicates that most of its energy is being emitted by stars with three solar masses or less. Hence, as larger stars will exist for shorter periods, this galaxy has an age of more than 300 million years. The period of initial active star formation in this galaxy may have lasted less than 100 million years, during which the galaxy likely participated in the reionization event.