Stars and Dust in Corona Australis
Cosmic dust clouds and young, energetic stars
this telescopic vista
less than 500 light-years away toward the northern boundary of
, the Southern Crown.
The dust clouds effectively block light
more distant background stars in the
But the striking complex of reflection nebulae cataloged as
NGC 6726, 6727,
and IC 4812
produce a characteristic color as blue light
from the region's young, hot stars is
the cosmic dust.
from view stars
still in the process
At top right, smaller yellowish nebula NGC 6729 bends around
young variable star
Near it, glowing arcs and loops
shocked by outflows
from embedded newborn stars
are identified as Herbig-Haro objects
On the sky this field of view spans about 1 degree.
That corresponds to almost 9 light-years at the estimated
distance of the nearby star forming region.
Cocoon Nebula Deep Field
Inside the Cocoon Nebula is a newly developing cluster of stars.
The cosmic Cocoon on the upper right also punctuates
a long trail of obscuring interstellar dust
clouds to its left.
the beautiful nebula is nearly 15 light-years wide, located
some 3,300 light years away toward the northern constellation of the Swan
Like other star forming regions, it stands out
in red, glowing, hydrogen gas
excited by young, hot stars and blue, dust-reflected
at the edge of a nearly invisible
In fact, the bright star near the center of this nebula is likely
only a few hundred thousand years old, powering the nebular glow as it
slowly clears out
a cavity in the
's star forming dust and gas.
exceptionally deep color view
of the Cocoon Nebula traces
tantalizing features within and surrounding the dusty
Salt Pepper and Ice
There's a "camera" comet now moving across the sky.
Just a bit too dim to see with the unaided eye,
Comet 21P / Giacobini-Zinner
has developed a
that makes it a good sight for binoculars and sensitive cameras.
The movement of the
on the sky was captured last week in the
featured time-lapse video
compressing 90 minutes into about 2.5 seconds.
What might seem odd is that the
is not following the comet's movement.
This is because
always point away from the Sun, and
was not moving toward
during the period photographed.
Visible far in the background on the upper left is the Salt & Pepper star cluster,
, while the bright red star
is visible just about the frame's center.
This 2-km ball of
passed its nearest to the Sun and Earth only last week
and is now fading as it
crosses into southern skies
Comet 21P should remain visible, however, and photogenic to
, for another month or so.
Cosmic Collision Forges Galactic Ring
How could a galaxy become shaped like a ring?
The rim of the blue galaxy
on the right is an immense ring-like structure 150,000
in diameter composed of newly formed, extremely bright,
That galaxy, AM 0644-741
, is known as a
and was caused by an
immense galaxy collision.
When galaxies collide
they pass through each other -- their individual stars
rarely come into contact.
-like shape is the result of the
caused by an entire
galaxy passing through a large one.
When this happens, interstellar gas and
become condensed, causing a
wave of star formation
to move out from the impact point like a
ripple across the surface of a pond.
The likely intruder galaxy is on the left of this combined image from
) space telescopes.
X-ray light is shown in pink and
black holes or neutron stars
likely formed shortly after the
A Solar Filament Erupts
What's happened to our Sun?
Nothing very unusual -- it just
threw a filament
Toward the middle of 2012, a long standing
suddenly erupted into space producing an energetic Coronal Mass Ejection (CME).
had been held up for days by the Sun's ever changing
and the timing of the eruption was unexpected.
by the Sun-orbiting Solar Dynamics Observatory, the resulting
electrons and ions into the Solar System, some of which arrived at Earth three days later and impacted Earth's
, causing visible
Loops of plasma surrounding an
can be seen above the erupting filament in
Although the Sun is now in a
state of its
have opened in the
allowing an excess of
to stream into space.
As before, these charged particles are
Mont Blanc, Meteor, and Milky Way
is near the center of this atmospheric night skyscape.
But high, thin clouds fogged the skies at the photographer's location,
looking south toward Europe's highest peak from the southern Swiss Alps.
Still, the 13 second exposure finds the faint star fields and dark rifts of
the Milky Way
Bloated by the mist, bright planet Saturn and Antares (right),
alpha star of Scorpius, shine through the clouds to flank the
galaxy's central bulge.
scene is from
the rewarding night of August 12/13, so it also
includes the green trail of a Perseid
along the galactic plane.
Ice Halos at Yellowknife
You've probably seen
around the Sun before
More common than rainbows, ice halos,
like a 22 degree circular halo for example, can be easy to spot,
especially if you can shade your eyes from direct sunlight.
Still it's rare to see such a diverse
range of ice halos
, tangent, infralateral, and Parry arcs,
all found in this
from planet Earth.
The picture was quickly taken in the late morning of
September 4 from Yellowknife, Northwest Territories, Canada.
The beautiful patterns are generated as sunlight
is reflected and refracted in six-sided water ice crystals
in Earth's atmosphere.
Of course, atmospheric ice halos in the skies of
to be different
Comet, Clusters, and Nebulae
Bright enough for binocular viewing
Comet 21P /
stands out, even in this
of the star cluster
and nebula rich constellation Auriga
On the night of September 9 its greenish coma and diffuse tail contrast
with the colorful stars and reddish emission nebulae in the
almost 10 degree field of view along the Milky Way.
The comet was near its perihelion and closest approach to Earth,
about 200 light-seconds away.
Riding across the distant background just above the comet's tail
are well-known Auriga star clusters M38 (left of center) and
M36 (toward the right) about 4,000 light-years away.
At the top left, emission region IC 405 is only 1,500 light-years
distant, more dramatically known as the
Flaming Star Nebula
To its right lies IC 410, 12,000 light-years away and
famous for its star-forming
A child of
Giacobini-Zinner is a periodic
comet orbiting the Sun once every 6.5 years, and
the parent body of October's
Draconids meteor shower
Lunations - 21Set2018 07:58:07
Our Moon's appearance changes nightly.
the half illuminated by the
first becomes increasingly visible, then decreasingly visible.
The featured video
animates images taken by NASA's Moon-orbiting
Lunar Reconnaissance Orbiter
to show all
12 lunations that appear this year, 2018.
describes one full cycle of our Moon, including all of its
takes about 29.5 days, just under a month
progresses, sunlight reflects from the
at different angles, and so
During all of this, of course,
always keeps the same face toward the
What is less apparent night-to-night is that
's apparent size changes slightly,
and that a slight wobble called a
occurs as the
progresses along its elliptical orbit
Milky Way over Trolls Tongue
You have to take a
to see the Troll's Tongue -- ten hours over rocky terrain.
And in this case, it took three trips to capture the
below a clear night sky.
itself is a
picturesque rock protrusion
extending about 700 meters over mountainous cliffs near
is made of billion-year-old
that was carved out by glaciers during an ice-age about 10,000 years ago.
The featured picture
is a composite of two exposures, a 15-second image of the
followed 40 minutes later by an 87-second exposure of the
Thousands of discernable stars dot the backdrop
in addition to billions of
unresolved stars in the nearly vertical
band of our Milky Way Galaxy
Curiosity Vista from Vera Rubin Ridge
If you could stand on Mars -- what might you see?
If you were NASA's
, just last month you would have seen
the view from Vera Rubin Ridge
intriguing rock-strewn perch
on the side of
featured 360-degree panorama
, you can spin around and take in
from all directions,
in many browsers, just by pointing or
In this virtual reality
view, many instruments on
are labelled, including antennas, the robotic arm, and the radioisotope thermoelectric generator
Dark sand and light rock cover the ground nearby in a mixture called lakebed mudstone.
Towering Mount Sharp
is only barely visible in the distance due to airborne dust from a
just winding down.
, Curiosity has found that the
raw ingredients for life
are present on Mars.
Next on Mars
will be NASA's
, on target
in late November,
which is scheduled to deploy a
to better study the interior of the
M1: The Crab Nebula from Hubble
This is the mess that is left when a star explodes.
The Crab Nebula
, the result of a supernova
, is filled with mysterious
are not only
tremendously complex, but appear to have
less mass than expelled
in the original supernova and a
higher speed than expected
from a free explosion.
The featured image
taken by the Hubble Space Telescope
is presented in three colors chosen for
The Crab Nebula
spans about 10 light-years
In the nebula
's very center lies a
as massive as the
but with only the size of a
The Crab Pulsar
rotates about 30 times each second.
Real Time Perseid
and dark night skies made
this year's Perseid meteor shower a great time for a
And while packing away their equipment, skygazers
at a campsite in the mountains of southern Germany
found at least one more reason to linger under the stars,
witnessing this brief but colorful flash with their own eyes.
Presented as a 50 frame gif
the two second long video was captured
during the morning twilight of August 12.
In real time it shows the development of the
green train of a
bright Perseid meteor.
A much fainter Perseid is just visible farther to the right.
Earth's atmosphere at 60 kilometers per second,
Perseids are fast enough to excite the characteristic green
emission of atomic oxygen at altitudes of 100 kilometers or so.
Saturn s North Polar Hexagon
In full view
the amazing six-sided jet stream known
as Saturn's north polar hexagon is shown in this
colorful Cassini image.
Extending to 70 degrees north latitude,
the false-color video frame is map-projected, based on infrared,
visible, and ultraviolet image data recorded by the
Saturn-orbiting spacecraft in late 2012.
First found in the outbound Voyager
flyby images from the 1980s, the
tied to the planet's rotation is about 30,000 kilometers across.
At its center lies the
ringed gas giant's hurricane-like
north polar storm
A new long term study of Cassini data has found a remarkable
higher-altitude vortex, exactly matching the outlines of the
north polar hexagon, that formed as summer approached the planet's
It appears to reach hundreds of kilometers
above these deeper cloud tops,
Along the Western Veil
Delicate in appearance, these filaments of shocked, glowing gas,
are draped across planet Earth's sky toward the constellation of Cygnus.
They form the western part of
The Veil Nebula itself is a large
, an expanding
cloud born of the death explosion of a massive star.
Light from the original supernova explosion likely reached
Earth over 5,000 years ago.
Blasted out in the cataclysmic event, the interstellar shock wave
plows through space sweeping up and exciting interstellar material.
The glowing filaments are really more like long ripples in a sheet seen
almost edge on, remarkably well separated into
atomic hydrogen (red) and oxygen (blue-green) gas.
Also known as the Cygnus Loop, the
nearly 3 degrees or about 6 times the diameter of
the full Moon.
While that translates to over 70 light-years
at its estimated distance of 1,500 light-years, this telescopic
two panel mosaic
image of the western portion spans about
half that distance.
Brighter parts of the western Veil are
recognized as separate nebulae, including The
(NGC 6960) along the top of this view and
below and left.
NGC 3682: Sideways Spiral Galaxy
What do spiral galaxies look like sideways?
Featured is a sharp telescopic view of a magnificent edge-on spiral
, a puffy
divided by dark dust lanes.
Of course, this
deep galactic portrait
puts some astronomers
of its popular moniker,
The Hamburger Galaxy.
The tantalizing island
is about 100,000 light-years across and 35 million
s away in the northern springtime
shares its neighborhood in the
with two other large spirals
in a grouping
otherwise known as the Leo Triplet
its cosmic neighbors are likely responsible for the extended flare and
of this spiral's disk.
Moon behind Lava Fountain
What's happened to the Moon?
Nothing, but something has happened to the image
of the Moon.
The heat from a
volcanic lava fountain
in the foreground has warmed and made
the air nearby, causing passing light to
differently than usual.
The result is a
that appears to be
The featured picture was taken as the full
about one week ago.
The picture is actually a
composite of two
one taken right after the other, with the same camera and lens.
was a quick exposure to capture details of the setting Moon, while the
taken after the Moon set a few minutes later,
was longer so as to capture details of the faint lava jets.
From our Earth, we can only see the
, planets, and stars as they appear through the distortion of the
This distortion can not only change the images of familiar orbs into
, it can --unexpectedly at times --
and moonset by several minutes.
Aurora around Saturns North Pole
Are Saturn's auroras like Earth's?
To help answer this question, the
Hubble Space Telescope
monitored Saturn's North Pole simultaneously during
Cassini's final orbits
around the gas giant in September 2017.
During this time,
's tilt caused its North Pole to be
The featured image
is a composite of
of aurora and optical images of
Saturn's clouds and rings, all taken recently by Hubble.
Like on Earth, Saturn's northern auroras can make
total or partial rings
around the pole.
Unlike on Earth, however,
are frequently spirals --
and more likely to peak in brightness just before midnight and dawn.
In contrast to
appear better related to connecting
Saturn's internal magnetic field to the nearby, variable,
Saturn's southern auroras
were similarly imaged back in 2004 when the
planet's South Pole
was clearly visible to Earth.
A Powerful Solar Flare
was one of the
most powerful solar flares
in recorded history.
Occurring in 2003 and seen across the electromagnetic spectrum
briefly became over 100 times brighter in
The day after this
17 solar flare -- and subsequent
Coronal Mass Ejection
emitted from the explosions struck the Earth,
and affecting satellites.
The spacecraft that took these frames --
-- was put in a turtle-like safe mode
to avoid further damage from this and
subsequent solar particle storms
featured time-lapse movie
condenses into 10 seconds
events that occurred over 4 hours.
The CME, visible around the central sun-shade, appears
about three-quarters of the way through the video,
while frames toward the very end are progressively noisier as
from the explosions
strike SOHO's LASCO detector.
One this day in 1859, the effects of an even more powerful solar storm caused telegraphs on Earth to spark in what is known as the
such as these may create
but they also pose a real danger as they can
satellites and even power grids across the Earth.
On August 23, 2018
the identification and distribution of
in the Earth's atmosphere is shown in this dramatic,
Produced in real time, the Goddard Earth Observing System Forward
Processing (GEOS FP
model relies on a combination of
ground-based data to calculate the presence of types of aerosols,
tiny solid particles
and liquid droplets, as they circulate above the entire planet.
This August 23rd model shows black carbon particles in red
from combustion processes,
like smoke from the fires in the United States and Canada,
spreading across large stretches of North America and Africa.
Sea salt aerosols are in blue, swirling above threatening typhoons near
South Korea and Japan, and the hurricane looming near Hawaii.
Dust shown in purple hues is blowing over African and Asian deserts.
The location of cities and towns can be found from the
concentrations of lights based on satellite image data of
the Earth at night
Close Mars - 21Set2018 07:58:07
Still bright in evening skies,
Mars was just past opposition
and closest to Earth on July 31,
a mere 57.6 million kilometers away.
Captured only a week later, this remarkable image shows the
Red Planet's disk
near its maximum size in earthbound telescopes,
but still less than 1/74th the apparent diameter of a Full Moon.
Broad regional surface shadings are starting to reappear in the
view as the latest planet-wide
With the bright south polar cap at the bottom, the Valles
Marineris extends along the center of the disk.
the roughly circular Solis Lacus region
sometimes known as the
Eye of Mars
In a line, three prominent dark spots left of center are the volcanic
The NGC 6914 Complex
A study in contrasts,
stars, dust, and glowing gas
in the vicinity of NGC 6914.
of reflection nebulae
lies some 6,000 light-years away,
toward the high-flying northern constellation
Cygnus and the plane
Milky Way Galaxy.
Obscuring interstellar dust clouds appear in
silhouette while reddish hydrogen
, along with the
dusty blue reflection
, fill the
Ultraviolet radiation from the massive, hot, young stars of the
association ionize the region's atomic
the characteristic red glow as protons and electrons recombine.
Embedded Cygnus OB2 stars also provide the
blue starlight strongly reflected by the dust clouds.
The nearly 1 degree wide telescopic field of view spans
about 100 light-years at the estimated distance of NGC 6914.