It wasn't until 2012 that a pair of dwarf spheroidal galaxies
were discovered in NGC 4449's halo.
TEHRAN (FNA)- A team of astronomers discovered that our nearest galactic neighbors, the dwarf spheroidal galaxies, are devoid of star-forming gas, and that our Milky Way Galaxy is to blame.
Astronomers wondered if, after billions of years of interaction, the nearby dwarf spheroidal galaxies have all the same star-forming 'stuff' that we find in more distant dwarf galaxies," said astronomer Kristine Spekkens, assistant professor at the Royal Military College of Canada and lead author on a paper published in the Astrophysical Journal Letters.
These past observations, however, were not sensitive enough to rule out the presence of this gas in the smallest dwarf spheroidal galaxies.
One of the best places to look for these faint gamma-ray signals is in dwarf spheroidal galaxies
, small satellites of our own Milky Way galaxy that we know possess large amounts of dark matter," Siegal-Gaskins explained.
These dwarf spheroidal galaxies, which are members of the Local Group, were only discovered in 1950 by US astronomers Robert Harrington and Albert Wilson examining the Palomar Observatory Sky Survey (POSS) plates.
Dwarf spheroidal galaxies are similar in many respects to elliptical galaxies.
Dust mass-loss rates from asymptotic giant branch stars in the Fornax and Sagittarius dwarf spheroidal galaxies
, Monthly Notices of the Royal Astronomical Society, 383, 399-410
Washington, July 30 (ANI): In an interesting new research, astronomers have determined that dwarf spheroidal galaxies, which contain few stars relative to their total mass, are formed by indulging in a cosmic dance.
Dwarf spheroidal galaxies appear to be made mostly of dark matter - a mysterious substance detectable only by its gravitational influence, which outweighs normal matter by a factor of five to one in the universe as a whole.
Astronomers have found it difficult to explain the origin of dwarf spheroidal galaxies.