N90.Name

Many spiral galaxies have bars across their centers. Even our ownMilky Way Galaxy is thought to have amodest central bar.Prominently barred spiral galaxy NGC 6217,pictured above, was captured in spectacular detail in this recentlyreleased image taken by the newly repairedAdvanced Camera for Surveys on theorbiting.Visible are dark filamentarydust lanes, youngclusters of bright blue stars, redemission nebulas of glowing hydrogen gas,a long bright bar of stars across the center, and a brightactive nucleusthat likely houses a supermassiveblack hole. Light takes about 60 million years to reach us fromNGC 6217, which spans about 30,000light years across and can be found toward theconstellation of the Little Bear(Ursa Minor).

Big, beautiful spiral galaxy M101 is one of the lastentries in Charles Messier’sfamous catalog, but definitely notone of the least.About 170,000 light-years across,this galaxy is enormous, almosttwice the size of our own Milky Way Galaxy.M101 was also one of the originalspiralnebulaeobserved by Lord Rosse’s large 19th century telescope, theLeviathanof Parsontown.Recorded atinfrared wavelengthsby the Spitzer Space telescope, this21st century viewshows starlight in blue hues while the galaxy’sdust clouds are in red.Examining the dust features in the outer rim of thegalaxy,astronomershave found that organic molecules present throughoutthe rest of M101 are lacking.The organic molecules tracked by Spitzer’s instruments arecalled polycyclic aromatic hydrocarbons(PAHs).Of course, PAHs are common components of dust in theMilky Wayand on planet Earth are found in soot.PAHs are likely destroyed near the outer edges of M101 by energeticradiation in intense star forming regions.Also known as thePinwheel Galaxy,M101 lies within the boundaries of the northern constellationUrsa Major, about 25 million light-yearsaway.

The graceful arc of the Milky Waybegins and ends at twomountain peaks in this solemn night sky panorama.Created from a 24 frame mosaic, exposures tracking Earth and skywere made separately, with northern California’s Mount Lassen at theleft and Mount Shasta at the far right, just below thestar and dust clouds of the galacticcenter.Lassen and Shasta are volcanoes in theCascade Mountain Rangeof North America, an arc of the volcanic Pacific Ring of Fire.In the dim, snow-capped peaks,planet Earth seems to echothe subtle glow of the Milky Way’s own faint, unresolvedstarlight