Hubble Space Telescope Zooms In on Outer Arms of NGC 45
Astronomers using the NASA / ESA Hubble space telescope captured an astonishing new image of part of a spiral galaxy called NGC 45.
This Hubble image shows the outer arms of NGC 45, a spiral galaxy at around 22 million light years in the Constellation of Cetus. The color image was made from separate exhibitions taken in the ultraviolet regions, visible and close to the spectrum with the Large Camera 3 (WFC3) instrument. It is based on the data obtained via seven filters. The color results from the allocation of different shades to each monochromatic image associated with an individual filter. Image credit: NASA / ESA / Hubble / D. Calzetti / R. Chandar / MH Özsaraç.
NGC 45 is located about 22 million light years in the Constellation of Cetus.
Also known as DDO 223, ESO 473-1 or LEDA 930, this galaxy has around 81,000 light years in diameter.
NGC 45 was discovered by English astronomer John Herschel on November 11, 1835.
“The Hubble data used to create this portrait of NGC 45 have been taken from two additional observation programs,” Hubble Astronomers said in a press release.
“The first took a wide view of 50 galaxies nearby, taking advantage of the capacity of Hubble to observe the light of the ultraviolet in almost infrared in order to study the formation of stars in these galaxies.”
“The second program examined many of the same galaxies nearby as the first, narrowing over a particular wavelength of red light called H-Alpha.”
“The nebulae forming stars are powerful H-Alpha light producers, and several of these regions can be identified on NGC 45 by their bright red color.”
“These observation programs aimed to study the formation of stars in galaxies of different sizes, structures and degrees of isolation – and NGC 45 is a particularly interesting target.”
Although it may seem like a regular spiral galaxy, NGC 45 is actually a remarkable type called low surface light galaxy.
“Low surface light galaxies are lower than the night sky itself, which makes them incredibly difficult to detect,” said the researchers.
“They seem unexpected to evacuation because they have relatively few stars for the amount of gas and dark matter they wear.”
“During the decades which followed the first galaxy of low surface lights were discovered in a fortuitous way in 1986, the researchers learned that 30 to 60% of all the galaxies can fall into this category.”
“The study of these galaxies that are difficult to detect is the key to understanding how galaxies are formed and evolving, and the sensitive instruments of Hubble are equal to the task.”
