Collapse in Hebes Chasma on Mars
What's happened in Hebes Chasma on Mars?
Hebes Chasma is a depression just north of the enormous
Since the depression is unconnected to other surface features, it is
the internal material went.
Inside Hebes Chasma
a 5 kilometer high mesa that appears to have undergone an unusual partial collapse --
a collapse that might be providing clues.
The featured image
, taken by ESA's robotic
spacecraft currently orbiting
, shows great details of the chasm and the unusual
shaped indentation in the central mesa.
Material from the mesa appears to have flowed onto the floor of
while a possible dark layer appears to have pooled like ink on a downslope landing.
A recent hypothesis holds
that salty rock composes some lower layers in
with the salt dissolving in melted ice flows that drained through holes into an underground
Comet Clark is near the Edge
Sweeping through this stunning field of view,
really is in the foreground of these cosmic clouds.
The 2 panel telescopic mosaic is color enhanced and is about 5 degrees
(10 full moons) across.
It captures the faint
position on the
night of May 23/24 over 5 light-minutes from Earth,
very near the line-of-sight to
bright star Antares
Rho Ophiuchi cloud complex.
In the frame
, also known as Alpha Scorpii, is at bottom center surrounded
by a dusty cosmic cloud reflecting the cool giant star's yellowish light.
Globular star cluster M4 shines just right of Antares,
but M4 lies some 7,000 light-years away compared to Antares'
500 light-year distance.
Slightly closer than Antares, Rho Ophiuchi's bluish starlight is
reflected by the dust in
toward the top.
You can spot the small coma and short tail of the comet
as a faint smudge near the center of the left edge of the frame.
Just look for the comet's striking greenish color, produced as diatomic
carbon molecules fluoresce
Spiral Galaxy NGC 6744
Big, beautiful spiral galaxy NGC 6744
is nearly 175,000 light-years
across, larger than
our own Milky Way
It lies some 30 million light-years distant in the southern
constellation Pavo appearing as a faint, extended object in
We see the disk of the nearby island universe tilted towards our
line of sight.
remarkably distinct and detailed galaxy portrait
covers an area about the angular size
of the full moon
In it, the giant galaxy's yellowish core is dominated by the light from
old, cool stars.
Beyond the core, spiral arms filled with
young blue star clusters and pinkish star forming regions sweep past
a smaller satellite galaxy at the lower left,
reminiscent of the Milky Way's satellite galaxy the Large
Star Cluster, Spiral Galaxy, Supernova
A cosmic snapshot from May 19,
this colorful telescopic field of view spans about 1 degree
or 2 full moons on the sky.
Spiky in appearance, foreground Milky Way stars are scattered
toward the royal constellation
of open cluster NGC 6939 gather about 5 thousand light-years in the distance
near the top of the frame.
galaxy NGC 6946
is toward the lower left nearly
22 million light-years away.
The helpful red lines identify recently discovered
, the death explosion of a massive star nestled
in the galaxy's bluish spiral arms.
in the last 100 years, 10 supernovae have been discovered in NGC 6946.
By comparison, the average rate of supernovae in our Milky Way is about 1
every 100 years
Of course, NGC 6946 is also known as
The Fireworks Galaxy
NGC 4565: Galaxy on Edge
Is our Galaxy this thin?
We believe so.
Magnificent spiral galaxy
is viewed edge-on from planet Earth.
Also known as the Needle Galaxy
for its narrow profile, bright NGC 4565 is a stop
on many telescopic tours of the northern sky,
in the faint but well-groomed
This sharp, colorful image reveals the galaxy's bulging central core
cut by obscuring dust lanes
NGC 4565's thin
An assortment of other background galaxies is
in the pretty field of view
neighboring galaxy NGC 4562 at the upper left.
NGC 4565 itself lies about 40 million
distant and spans
some 100,000 light-years.
Easily spotted with small telescopes,
consider NGC 4565 to be a prominent celestial masterpiece
What would it look like to approach Jupiter?
To help answer this, a team of 91 amateur
astrophotographers took over 1,000 pictures
of Jupiter from the Earth with the resulting images aligned and digitally merged into the featured time-lapse video.
Image taking began in 2014 December and lasted just over three months.
The resulting fictitious approach sequence has similarities to what was seen by NASA's robotic
begins with Jupiter appearing as a small orb near the image center.
As Jupiter nears from below, the planet looms ever larger while the
rotation of its cloud bands
shrinking Great Red Spot
rotates into view twice, at times showing
Many white ovals
are visible moving around the giant planet.
The video ends as the imaginary spacecraft passes over Jupiter's North Pole.
A Zodiacal Sky over Horseshoe Bend
What's causing the unusual ray of white light extending upward from the central horizon?
orbiting the Sun.
At certain times of the year, a band of sun-reflecting dust from the inner
rises prominently before sunrise and is called
The dust originates mostly from faint
and slowly spirals into the
, in front of the zodiacal light, is a spectacular view of
of the Colorado River
Emitted from well behind the
is a spectacular sky that
many bright stars including
several blue star clusters including the
, and an assortment of red nebula including
The 30-image composite was taken earlier this month in
nearly complete darkness
only six inches from the edge of a
In the Center of the Lagoon Nebula
The center of the Lagoon Nebula is a
of spectacular star formation.
Visible on the lower left, at least two long funnel-shaped clouds,
each roughly half a light-year
long, have been formed by extreme
and intense energetic starlight.
The tremendously bright nearby star,
, lights the area.
Vast walls of dust
other hot young stars.
As energy from these stars pours into the
large temperature differences in
can be created generating
which may cause the funnels.
, spanning about 5 light years, was taken in 1995 by the
orbiting Hubble Space Telescope
, also known as
, lies about 5000
distant toward the
A View Toward M101
Big, beautiful spiral galaxy M101 is one of the last
entries in Charles
famous catalog, but definitely not
of the least
About 170,000 light-years across, this galaxy is enormous,
almost twice the size of our own Milky Way galaxy.
M101 was also one of the original
observed by Lord Rosse's large
telescope, the Leviathan
M101 shares this modern telescopic field of view with
spiky foreground stars within the Milky Way, and more
distant background galaxies.
The colors of the Milky Way
stars can also be
found in the starlight from the large island universe.
Its core is dominated by light from cool yellowish stars.
its grand spiral arms are the blue colors of hotter, young stars mixed
with obscuring dust lanes and pinkish star forming regions.
Also known as the
the boundaries of the northern constellation Ursa Major,
about 25 million light-years away
Named for the three astronomers instrumental in its discovery and
(WLM) is a lonely dwarf galaxy.
Seen toward the mostly southern constellation Cetus,
about 3 million light-years from the Milky Way,
it is one of the most remote members of
our local galaxy group
In fact, it may never have interacted with any other local group galaxy.
Still, telltale pinkish star forming regions and hot, young, bluish
stars speckle the isolated island universe.
Older, cool yellowish stars fade into the
extending about 8,000 light-years across.
This sharp portrait
was captured by the
268-megapixel OmegaCAM widefield imager
and survey telescope at ESO's Paranal Observatory.
Simeis 147: Supernova Remnant
It's easy to get lost following intricate filaments in this
detailed image of faint
Also cataloged as Sharpless 2-240 it goes by the popular nickname,
the Spaghetti Nebula.
the boundary of the constellations Taurus and Auriga,
it covers nearly 3 degrees or 6 full moons on the sky.
That's about 150 light-years at
the stellar debris cloud's estimated distance of 3,000 light-years.
This composite includes image data taken through narrow-band filters,
enhancing the reddish emission from ionized hydrogen atoms to trace the
shocked, glowing gas
The supernova remnant has an estimated age of about 40,000
years, meaning light from the massive stellar explosion first
reached Earth 40,000 years ago.
But the expanding remnant is not the only aftermath.
The cosmic catastrophe
also left behind
a spinning neutron star or pulsar,
all that remains of the original star's core.
Galaxy Group Hickson 90
Scanning the skies for galaxies, Canadian astronomer
Paul Hickson and colleagues identified some 100 compact
, now appropriately called
Hickson Compact Groups (HCGs).
This sharp Hubble image
shows one such galaxy group
, HCG 90, in
-- two visible here -- are revealed to be strongly interacting:
stretched and distorted in the image center, and two large
The close encounter will trigger
furious star formation
On a cosmic timescale, the gravitational tug of war will eventually
in the merger
of the trio into a large single galaxy.
The merger process is now understood to be a normal part of the evolution of
our own Milky Way
HCG 90 lies about 100 million light-years away toward
the constellation of the Southern Fish
This Hubble view
spans about 40,000
at that estimated distance.
Hickson Compact Group
s also make for
for Earth-bound astronomers
with more modest sized telescopes.
Gemini Stars Pollux and Castor
Who are the twins of Gemini?
It terms of astronomical objects, the
is dominated by two bright stars:
the two stars stand out because they are so bright,
so close together
both in angle and brightness, but so different in color.
Pollux, at 33 light years distant, is an evolved red giant star twice as massive as our Sun.
Castor, at 51 light years distant, is a blue main sequence
about 2.7 times more massive that our Sun.
Castor is known to have at least two
, while Pollux is now known to be circled by at least one
In terms of ancient
mythology, Castor and Pollux
Currently, the Earth's orbit is causing the Sun to appear to shift in front of the constellation of Gemini, with the result that, for much of humanity,
Castor and Pollux
will remain visible toward the west at sunset for only a few more weeks.
Lightning Storm Moves Across the USA
Watch a huge lightning storm move across the eastern USA.
The huge storm caused much damage and unfortunately some loss of life for people in its path.
Seen from space, the
is seen as momentary flashes in the featured
recorded last month by the
Geostationary Lightning Mapper
(GLM) aboard the
The outline of
is most evident during the day, while the bright
are most evident at night.
Inspection of the video shows that much of the
at the leading edge of the huge tail of the swirling storm.
frequently precedes a storm's most violent impact,
holds promise to help reduce the harm to humans from future storms.
Ganymede: The Largest Moon
What does the largest moon in the
, larger than even
, has an icy surface speckled with bright young craters overlying a mixture of older, darker, more cratered terrain laced with grooves and ridges.
The large circular feature on the upper right, called
is an ancient region of
Ganymede is thought to have an
more water than Earth
might contain life
Like Earth's Moon, Ganymede keeps the
same face towards
its central planet, in this case Jupiter.
The featured image
was taken about 20 years ago by NASA's
which ended its mission by diving into Jupiter's atmosphere in 2003.
orbits Jupiter and is
the giant planet's internal structure, among many other attributes.
bizarre alien planet is this?
It's planet Earth of course, seen from the
International Space Station
through the shimmering glow of aurorae.
About 400 kilometers (250 miles) above Earth,
the orbiting station is itself within
the upper realm
of the auroral displays.
Aurorae have the
colors of excited
atoms at the low densities found at extreme altitudes.
Emission from atomic oxygen dominates this view.
The eerie glow
is green at lower altitudes, but a rarer reddish band extends
above the space station's horizon.
Also visible from the planet's surface, this auroral display began during a
The storm was triggered after a coronal mass ejection
impacted Earth's magnetosphere in June of 2015.
M13: The Great Globular Cluster in Hercules
, English astronomer
"This is but a little Patch, but it shews itself to the naked Eye, when
the Sky is serene and the Moon absent."
Of course, M13
is now less modestly recognized as the Great Globular Cluster in Hercules,
one of the brightest
in the northern sky.
Telescopic views reveal the
spectacular cluster's hundreds of thousands
At a distance of 25,000 light-years, the
into a region 150 light-years in diameter.
the cluster core
upwards of 100 stars could be contained
in a cube just 3 light-years on a side.
For comparison, the
to the Sun is over
4 light-years away.
Along with the cluster's dense core, the outer reaches of M13
are highlighted in this
sharp color image
The cluster's evolved
red and blue
giant stars show up in yellowish and blue tints.
The Multiwavelength Crab
The Crab Nebula is cataloged as M1, the first object on
famous list of things which are not comets.
In fact, the Crab
is now known to be a
, expanding debris from massive star's death explosion,
witnessed on planet Earth in 1054 AD.
brave new image
offers a 21st century
view of the Crab Nebula by presenting image data from across the
as wavelengths of visible light.
data are in purple, blue, green, and yellow hues.
From the ground,
Very Large Array
radio wavelength data is in shown in red.
One of the most exotic objects known to modern astronomers,
the Crab Pulsar
a neutron star spinning 30 times a second,
is the bright spot near picture center.
Like a cosmic dynamo,
this collapsed remnant of the stellar core
powers the Crab's emission across the electromagnetic spectrum.
Spanning about 12 light-years, the Crab Nebula is
6,500 light-years away in the constellation
UGC 1810: Wildly Interacting Galaxy from Hubble
What's happening to this spiral galaxy?
Although details remain uncertain, it surely has to do with an ongoing battle with its smaller galactic neighbor.
is labelled UGC 1810 by itself, but together with its
is known as
The overall shape of the UGC 1810 -- in particular its
blue outer ring
is likely a result of wild and
This ring's blue color is caused by massive stars that are
and have formed only in the past few million years.
The inner galaxy
appears older, redder, and threaded with cool
A few bright
appear well in the foreground, unrelated to
1810, while several galaxies are visible well in the background.
lies about 300 million light years away
the constellation of Andromeda.
Quite likely, UGC 1810 will
over the next billion years and settle into a classic
Big Dipper Above and Below Chilean Volcanoes
Do you see it?
This common question frequently precedes the rediscovery of one of the most commonly recognized configurations of stars on the northern sky: the
This grouping of stars is one of the few things that has likely been seen, and will be seen, by
The Big Dipper is not by itself a
Although part of the constellation of the Great Bear
(Ursa Major), the
that has been known by different names to different societies.
Five of the
Big Dipper stars
are actually near each other in
space and were likely formed at nearly the same time.
in the far part of the Big Dipper will lead one to
, the North Star, which is part of the
Relative stellar motions
will cause the
to slowly change its
over the next 100,000 years.
Pictured in late April, the
was actually imaged twice -- above and
below distant Chilean volcanoes
, the later reflected from an unusually calm lagoon.
Ancient Ogunquit Beach on Mars
This was once a beach -- on ancient Mars.
The featured 360-degree panorama
, was taken by the robotic
currently exploring the
evidence shows that at times long ago the area was underwater,
while at other times it was at the edge of an
The light peak in the central background is the top of
, the central feature in
where Curiosity has been deployed.
Curiosity is slowly ascending Mount Sharp.
Portions of the
in the foreground have been
The light colored
is composed of
that likely settled at the bottom of the now-dried lakebed.
The featured panorama
(interactive version here
was created from over 100 images acquired in late March and seemingly signed by the rover on the lower left.
Currently, Curiosity is carefully crossing deep
of dark sands on
Star Formation in the Tadpole Nebula
What's all of the commotion in the Tadpole nebula?
Dusty emission in the Tadpole nebula, IC 410,
lies about 12,000 light-years away in the northern constellation of the
The cloud of glowing gas is over 100 light-years across,
and radiation from embedded
open star cluster
the interstellar cloud
4 million years ago, bright newly formed cluster stars are seen
all around the star-forming nebula.
Notable near the image center are two relatively dense streamers of material trailing
away from the nebula's central regions.
Potentially sites of ongoing star formation in
shapes are about 10 light-years long.
The featured image
was taken in
by NASA's Wide Field Infrared Survey Explorer