Transcript Diapositiva 1

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.
http://antwarp.gsfc.nasa.gov/apod/