A lucky observation of an enigmatic cloud: The little-known nebula IRAS 05437+2502 billows out among the bright stars and dark dust clouds that surround it in this striking image from the Hubble Space Telescope. It is located in the constellation of Taurus (the Bull), close to the central plane of our Milky Way galaxy. Unlike many of Hubble’s targets, this object has not been studied in detail and its exact nature is unclear. At first glance it appears to be a small, rather isolated, region of star formation and one might assume that the effects of fierce ultraviolet radiation from bright young stars probably were the cause of the eye-catching shapes of the gas. However, the bright boomerang-shaped feature may tell a more dramatic tale. The interaction of a high velocity young star and the cloud of gas and dust may have created this unusually sharp-edged bright arc. Such a reckless star would have been ejected from the distant young cluster where it was born and would travel at 200 000 km/hour or more through the nebula. This faint cloud was originally discovered in 1983 by the Infrared Astronomical Satellite (IRAS), the first space telescope to survey the whole sky in the infrared. IRAS was run by the United States, the Netherlands, and the United Kingdom and found huge numbers of new objects that were invisible from the ground. This image was taken with the Wide Field Channel of the Advanced Camera for Surveys on Hubble. It was part of a “snapshot” survey. These are lists of observations that are fitted into Hubble’s busy schedule when possible, without any guarantee that the observation will take place — so it was fortunate that the observation was made at all! This picture was created from images taken through yellow (F606W) and near-infrared (F814W) filters. The exposure times were about eleven minutes per filter and the field of view is about 100 arcseconds across.

Name: IRAS 05437+2502
Type: Milky Way : Nebula : Type : Star Formation
Category: Nebulae
Constellation: Taurus
Release date: 14 June 2010, 10:00
Credit: ESA/Hubble, R. Sahai and NASA

A fine Hydra spiral: The small spiral galaxy NGC 2758 is captured in great detail in this image from the Advanced Camera for Surveys (ACS) on the NASA/ESA Hubble Space Telescope. It was first seen by the American astronomer Frank Muller, at the McCormick Observatory in Virginia in the 1880s. This galaxy lies in the constellation of Hydra (the Sea Serpent), the largest and longest constellation in the sky. This very sharp Hubble image shows many of the bright blue stars within the galaxy’s loosely wound spiral arms as well as a bright companion dwarf galaxy to the upper left. Many more distant galaxies lie in the background. NGC 2758 is a fine example of a spiral galaxy that is close enough for the structure to be seen very clearly. In this case the Hubble images were obtained as part of a study of the central redder “bulge” component of galaxies and how they form and evolve. This picture was created from ACS Hubble images taken through blue (F435W) and near-infrared (F814W) filters. The exposure times were 1050 s per filter and the field of view was about 3.4 arcminutes across.

Name: NGC 2758
Type: Local Universe : Galaxy : Type : SpiralLocal Universe : Galaxy : Size : Dwarf
Category: Galaxies
Constellation: Hydra
Distance: 120 million light years
Release date: 21 June 2010, 10:00
Credit: ESA/Hubble and NASA