Aurora Shimmer, Meteor Flash
Image Credit & Copyright:
Bjørnar G. Hansen
Explanation:
Northern Lights,
or
aurora borealis, haunted
skies
over the island of Kvaløya, near Tromsø Norway on 2009 December 13.
This 30 second long exposure records their shimmering
glow gently lighting the wintery coastal scene.
A study in contrasts, it also captures the sudden flash of
a fireball meteor from the excellent
Geminid meteor shower in 2009 December.
Streaking past familiar stars in the handle of the
Big Dipper, the trail points back
toward the constellation Gemini, off the top of the view.
Both aurora and meteors occur in Earth's upper atmosphere at altitudes
of 100 kilometers or so, but
aurora caused by energetic charged particles from the
magnetosphere,
while meteors are trails of
cosmic dust.
Toward the end of this week the
2014 Geminids meteor shower will peak, although they will
compete with the din of last quarter moonlight.
Eta Carinae and the Expanding Homunculus Nebula
Image Credit:
Hubble,
NASA,
ESA;
Processing & Copyright:
First Light,
J. L. Dauvergne, P. Henarejos
Explanation:
How did the Eta Carinae star system create this unusual expanding nebula?
No one knows for sure.
About 170 years ago, the southern star system
Eta Carinae (Eta Car)
mysteriously became the second
brightest star system in the night sky.
Twenty years later, after ejecting more mass than our Sun, Eta Car unexpectedly faded.
Somehow, this outburst appears to have created the
Homunculus Nebula.
The three-frame video features images of the nebula taken by the
Hubble Space Telescope
in 1995, 2001, and 2008.
The
Homunculus nebula's center is lit by light from a bright central star, while the
surrounding regions are expanding lobes of gas laced with filaments of dark
dust.
Jets bisect the
lobes emanating from the central stars.
Expanding debris includes streaming
whiskers and
bow shocks caused by collisions with
previously existing material.
Eta Car still undergoes
unexpected outbursts,
and its high mass and volatility make it a candidate to explode in a
spectacular supernova
sometime in the next few million years.
Sharpless 249 and the Jellyfish Nebula
Image Credit &
Copyright:
César Blanco
González
Explanation:
Normally faint and elusive, the Jellyfish Nebula is caught in
this alluring telescopic mosaic.
The scene is anchored right and left by two bright stars,
Mu
and
Eta
Geminorum, at the foot of the
celestial
twin while
the Jellyfish Nebula is the brighter arcing
ridge of emission with dangling tentacles below and right of center.
In fact, the cosmic jellyfish is part of bubble-shaped
supernova remnant IC 443, the expanding
debris cloud from a
massive
star that exploded.
Light from the explosion first reached planet Earth over 30,000 years
ago.
Like its cousin in
astrophysical waters the
Crab Nebula
supernova remnant, the Jellyfish Nebula is
known
to harbor a neutron star, the remnant of the collapsed stellar core.
An emission nebula cataloged as
Sharpless 249
fills the field at the upper left.
The Jellyfish Nebula is about 5,000 light-years away.
At that distance,
this narrowband composite image
would be about 300 light-years across.
The Seahorse of the Large Magellanic Cloud
Image Credit:
NASA,
ESA, and
M. Livio
(STScI)
Explanation:
It may look like a grazing
seahorse,
but the dark object toward the image right is actually a
pillar of smoky
dust about 20
light years long.
The curiously-shaped
dust structure occurs in our neighboring
Large Magellanic Cloud, in a star forming region
very near the expansive
Tarantula Nebula.
The energetic nebula is creating a
star cluster, NGC 2074,
whose center is visible just off the top of the image in the
direction of the neck of the seahorse.
The
representative color image was taken in 2008 by the
Hubble Space Telescope's
Wide Field Planetary Camera 2 in honor of
Hubble's 100,000th trip around the Earth.
As young stars in the cluster form, their light and
winds will slowly erode the
dust pillars away over the
next million years.
Stars and Dust Pillars in NGC 7822 from WISE
Image Credit:
WISE,
IRSA,
NASA;
Processing & Copyright :
Francesco Antonucci
Explanation:
Hot, young stars and cosmic pillars of gas and dust
seem to crowd into NGC 7822.
At the edge of a giant
molecular cloud toward the northern
constellation
Cepheus, this glowing star forming region
lies about 3,000 light-years away.
Within
the nebula, bright edges and complex dust sculptures
dominate this
detailed skyscape
taken in
infrared light by NASA's Wide Field Infrared Survey Explorer
(
WISE) satellite.
The atomic emission by the cluster's gas is
powered by energetic radiation from
the hot stars, whose powerful
winds and light also sculpt
and erode the denser pillar shapes.
Stars could still be forming
inside the pillars by
gravitational collapse, but as the pillars are
eroded away, any forming stars will ultimately be cut off from their
reservoir of
star stuff.
This field spans around 40
light-years at the estimated distance of
NGC 7822.
3D 67P
Image Credit:
ESA/Rosetta/Philae/ROLIS
Explanation:
Get out your red/blue glasses and float next to a comet!
The Rosetta mission lander Philae's ROLIS camera snapped the
two frames used to create
this
stereo anaglyph for 3D viewing during its
November 12 descent to the nucleus of Comet 67P/Churyumov-Gerasimenko.
The comet's curious double lobed nucleus is seen nearly end on
from a distance of about 3 kilometers, about 1 hour before
Philae arrived at the surface.
Philae's initial
landing site is near the center of the
front facing lobe.
Part of a landing gear foot cuts across the upper right corner,
in the close foreground of the 3D-view.
Philae bounced twice in the comet's weak gravity
after its first contact with the surface.
Using high resolution camera images from the Rosetta orbiter
along with data from the lander's instruments, controllers have
followed Philae's
impromptu
journey over the comet's surface and
have identified a likely area for its
final resting place.
Plato and the Lunar Alps
Image Credit &
Copyright:
Richard Bosman
Explanation:
The dark-floored, 95 kilometer wide crater Plato and
sunlit
peaks
of the lunar Alps (Montes Alpes) are highlighted in this
sharp digital snapshot of the
Moon's surface.
While the
Alps
of planet Earth were uplifted over millions of
years as continental plates slowly collided, the lunar Alps were likely
formed by a sudden collision that created the giant
impact
basin known as the
Mare Imbrium
or Sea of Rains.
The mare's generally smooth, lava-flooded floor is seen
below the bordering mountain range.
The prominent straight feature cutting through the mountains
is the
lunar Alpine Valley (Vallis Alpes).
Joining the Mare Imbrium and northern Mare Frigoris (Sea of Cold)
the valley extends toward the upper right, about 160 kilometers long
and up to 10 kilometers wide.
Of course, the large, bright
alpine
mountain below and right of the valley is named
Mont Blanc.
The tallest of the lunar Alps, it
reaches over 3 kilometers above the surface.
Lacking an atmosphere, not to mention
snow,
the lunar Alps are probably not an ideal location for a winter
vacation.
Still, a 150 pound skier
would
weigh a mere 25 pounds
on
the Moon.
above image in zoom-in below
Image Source -
http://apod.nasa.gov/apod/image/1412/MontesAlpesBosman.jpg
Milky Way over Moon Valley
Image Credit &
Copyright:
Rafael Defavari
Explanation:
Our Milky Way
Galaxy arcs over a
desolate landscape
in this fantastic
panoramic
night skyview.
The otherworldly scene looks across the arid, eroded terrain of the
Valle de la Luna
in the Chilean Atacama desert.
Just along the horizon are lights from San Pedro, Chile,
as well as the small villages of Socaire and Toconao, and
a tortuous road from the city of Calama to San Pedro.
Taken on October 18th, the five panel mosaic
also features the four galaxies easily visible from our
fair planet's dark sky regions.
At the far left, satellite galaxies known as the
Large and Small
Magellanic Clouds
are framed by their terrestrial namesakes.
Much fainter and at the right, beyond the Milky Way's central bulge,
is the Andromeda Galaxy.
The most
distant in view,
Andromeda lies some 2.5 million light-years away.
All Images from
NASA
