It lies close to the direction of the open cluster Messier 52. The "bubble" is created by the stellar wind from a massive hot, 8.7 magnitude young central star, the 15 ± 5 M☉ SAO 20575 (BD+60 2522). The nebula is near a giant molecular cloud which contains the expansion of the bubble nebula while itself being excited by the hot central star, causing it to glow.
Ancient Mars featured flowing rivers and sizable lakes — but that doesn't mean the Red Planet definitely could have supported life, one prominent researcher stresses.
The presence of liquid water is just one of many factors that researchers need to take into account when investigating the past or present habitability of Mars or any other cosmic body, astrobiologist and mineralogist Pamela Conrad wrote in a "Perspectives" piece published online on Dec. 11 in the journal Science.
"The things that make a place livable are numerous, and sometimes, there's a showstopper you didn't think of," Conrad, deputy principal investigator for the Sample Analysis at Mars instrument aboard NASA's Curiosity rover, told SPACE.com. "So it's important to take a poll of the diversity of attributes that could contribute to making an environment livable or not."