A Cathedral of Stellar Nativity

The star that is the brightest object located just above the gas cloud in the picture is Pismis 24. Estimates made from distance, brightness and standard solar models had estimated Pismis 24’s mass over 200 times that of our Sun, nearly making it the record holder. Close inspection of images taken with the Hubble Space Telescope, however, have shown that Pismis 24-1 derives its brilliant luminosity not from a single star but from a group of at least three. The component stars would still remain near 100 solar masses, making them among the more massive stars currently on record. Toward the bottom of the image, stars are still forming in the associated emission nebula NGC 6357 which resembles a Gothic cathedral from Earth’s point of view.

Image Credit: NASA

NGC 772

NGC 772 (aka Arp 78) is an unbarred spiral galaxy about 130 million light-years away in the constellation Aries. It’s roughly twice the size of the Milky Way Galaxy, about 200,00 light-years across, and is surrounded by several satellite galaxies. The tidal force from one of the satellites, the dwarf elliptical galaxy NGC 770, has distorted one of the spiral arms.

Image Credit: ESA / NASA

A Stellar Nursery

LH_95These swirls of gas and dust and the stars clustered in and around them are know as LH 95. It a region of low-mass, infant stars and their much more massive stellar neighbors found in the Large Magellanic Cloud.

The largest stars in LH 95 (those with at least 3X the mass of the Sun) generate strong stellar winds and high levels of UV radiation that heat the surrounding interstellar gas. The result is a bluish nebula of glowing hydrogen expanding outward into the molecular cloud that originally collapsed to form these massive stars. However, some dense parts of this star-forming region remain intact despite the stellar winds. The appear as dark dusty filaments in the picture. These dust lanes absorb some of the blue light emitted by the stars behind them causing them appear redder. Other parts of the molecular cloud have contracted to form infant stars, the fainter of which have a high tendency to cluster.

Image Credit: NASA

NGC 986

A spiral in a furnaceNGC 986 is found in the constellation of Fornax (The Furnace), located in the southern sky. NGC 986 is around 56 million light-years away, and its golden center and barred swirling arms are clearly visible in this image assembled from data captured by Hubble’s Wide Field and Planetary Camera 2. (The stars in the upper right appear a little fuzzy because a gap in the Hubble data was filled in with images from ground-based telescopes. The view  is accurate, but the resolution is no match for Hubble.)

Barred spiral galaxies are spiral galaxies with stars forming a central bar-shaped structure. NGC 986 has the characteristic S-shaped structure of this type of galaxy. Young blue stars can be seen dotted through the galaxy’s arms, and the core is also alight with star formation.

Image Credit: NASA / ESA