By: Araceli Escobar, 1º Bto B

NASA, 2012 October 8

Near the center of this sharp cosmic portrait, at the heart of the Orion Nebula, are four hot, massive starsknown as the Trapezium. Gathered within a region about 1.5 light-years in radius, they dominate the core of the dense Orion Nebula Star Cluster. Ultraviolet ionizing radiation from the Trapezium stars, mostly from the brightest star Theta-1 Orionis C powers the complex star forming region's entire visible glow. About three million years old, the Orion Nebula Cluster was even more compact in its younger years and a recent dinamical study indicates that runaway stllar colosion at an earlier age may have formed a black hole with more than 100 times the mass of the Sun. The presence of a black hole within the cluster could explain the observed high velocities of the Trapezium stars. The Orion Nebula's distance of some 1500 light-years would make it the closest known black hole to planet Earth. This picture was captured by Hubble Legacy Archive.

NASA, 2012 October 8

Ghostly in appearance, Abell 39 is a remarkably simple, spherical nebula about five light-years across. Abell 39 is a planetary nebula, formed as a once sun-like star's outer atmosphere was expelled over a period of thousands of years. Still visible, the nebula's central star is evolving into a hot white dwarf. Although faint, the nebula's simple geometry has proven to be a boon to astronomers exploring the chemical abundances and life cycles of stars. In this deep image recorded under dark night skies, very distant background galaxies can be found -- some visible right through the nebula itself. This picture was captured by: Adam Block, Mt. Lemmon SkyCenter, University of Arizona.

NASA, 2012 October 17.

Colorful aurorae erupted unexpectedly earlier this month, with green aurora appearing near the horizon and brilliant bands of red aurora blooming high overhead. A bright Moon lit the foreground of this picturesque scene, while familiar stars could be seen far in the distance. Although the geomagnetic storm that created these aurorae has since subsided, eruptions of White Dome Geyser continue about every 30 minutes. This photo was captured by Robert Howell.

NASA, 2012 October 18.

Alpha Centauri is the closest star system to the Sun. The Sun is at the upper right, shining in the background of the Milky Way. The cresent in the foreground is an artist's rendering of a planet now reported oriting Alpha Centauri B, making it the closest known exoplanet. It was discover by Xavier Dumusque et al.using the planet hunting HARPS. This planet has the same mass as earth but is not habitable because it orbits 3.2 days, about 0.04 times the Earth-Sun distance from its parent star. We can see too Alpha Centauri A, a star a liitle colder than the Sun. This photo was captured by European Southern Observatory, L Calçada, N. Risinger.