The Crown of the Sun
During a total
, the Sun's extensive outer atmosphere, or corona, is
an inspirational sight.
Streamers and shimmering features visible to the eye span a brightness
range of over 10,000 to 1, making them notoriously difficult to capture
in a single photograph.
But this composite of telescopic images
covers a wide range of exposure times to reveal
the crown of the Sun
in all its glory.
The aligned and stacked digital frames
were taken in clear skies
Stanley, Idaho in the Sawtooth Mountains during the Sun's
total eclipse on August 21.
A pinkish solar prominence extends
just beyond the right edge of the solar disk.
Even small details on the dark night side of the
New Moon can be made out, illuminated by sunlight
reflected from a Full Earth.
A Total Solar Eclipse over Wyoming
Will the sky be clear enough to see the eclipse?
This question was on the minds of many people attempting to view yesterday's
The path of total darkness crossed the mainland of the USA from coast to coast, from Oregon to South Carolina -- but a partial eclipse occurred above all of
Unfortunately, many locations saw predominantly clouds.
One location that did not was a bank of Green River Lake, Wyoming.
There, clouds blocked the Sun intermittantly up to one minute
Parting clouds then moved far enough away to allow
the center image of the featured composite sequence to be taken.
This image shows the corona of the Sun extending out past the central dark Moon that blocks our familiar Sun.
The surrounding images show the partial phases of the solar eclipse
both before and after totality.
Milky Way over Chilean Volcanoes
Sometimes, the sky mimics the ground.
Taken in 2017 May from the
the foreground of the
encompasses the dipping edge of the
of an extinct volcano.
echoing the dip below is the arch of our
Milky Way Galaxy
Many famous icons dot this southern nighttime vista, including the
center of our Milky Way Galaxy
on the far left,
the bright orange star Antares
also on the left,
the constellation of the Southern
near the top of the arch, and the red-glowing
on the far right.
Just above the horizon and splitting
two distant volcanic peaks
near the image center is the
Large Magellanic Cloud
-- the largest
of the Milky Way.
Time-Lapse: A Total Solar Eclipse
Have you ever
a total eclipse of the Sun?
This time-lapse movie
depicts such an eclipse in dramatic detail,
As the video begins, a slight dimming of the Sun and the surrounding Earth is barely perceptible.
As the Moon moves to
nearly the entire Sun, darkness sweeps in from the left --
the fully blocked part of the Sun.
At totality, only the bright
extends past the edges of
the Moon, and darkness surrounds you.
Distant horizons are still bright, though, as they are not
in the darkest part of the shadow
At mid-totality the darkness dips to the horizon below the
eclipsed Sun, created by the shadow cone
a corridor of shadow that traces back to the Moon.
ends -- usually after a few minutes --
the process reverses and
moves off to the other side.
Tomorrow afternoon's total solar eclipse --
visible as at least a partial eclipse over all of North America -- can be
some of which are being organized by
Total Solar Eclipse of 1979
From cold, clear skies over Riverton, Manitoba, Canada, planet Earth,
the solar corona surrounds the silhouette of the New Moon in this
telescopic snapshot of the total solar eclipse of February 26, 1979.
Thirty eight years ago, it was
the last total
visible from the contiguous United States.
The narrow path of totality ran through the northwestern
states of Washington, Oregon, Idaho, Montana, and North Dakota
before crossing into Canadian provinces Saskatchewan, Manitoba,
Ontario and Quebec.
Following the upcoming
August 21, 2017
total solar eclipse
crossing the U.S. from coast to coast,
an annular solar eclipse will be seen in
the continental United States on October 14, 2023,
visible along a route from Northern California to Florida.
next total solar eclipse
to touch the
continental U.S. will track across 13 states from
from Texas to Maine on April 8, 2024.
Perseids over the Pyrénées
This mountain and night skyscape
stretches across the French
Pyrenees National Park
on August 12,
near the peak of the annual Perseid meteor shower.
The multi-exposure panoramic view was composed from the
, a mountain pass, about an hour before
the bright gibbous moon rose.
Centered is a misty valley and lights from the region's
Gourette ski station toward the south.
Taken over the following hour, frames capturing some of
the night's long bright
were aligned against the backdrop of
stars and Milky Way
NGC 2442: Galaxy in Volans
galaxy NGC 2442 can be found in the southern constellation of the
Located about 50 million light-years away, the galaxy's two
spiral arms extending from a pronounced central bar have a hook-like
appearance in wide-field images
, constructed from Hubble Space Telescope and
European Southern Observatory data,
follows the galaxy's structure in amazing detail.
Obscuring dust lanes, young blue star clusters and
reddish star forming
surround a core of yellowish light from an older population of stars.
The sharp image data also reveal more distant
background galaxies seen right through NGC 2442's
star clusters and nebulae.
The image spans about 75,000 light-years at the estimated distance
of NGC 2442
Perseid by the Sea
Just after moonrise on August 12 this grain of cosmic sand
fell by the sea, its momentary flash part of the annual
Perseid Meteor Shower
To create the Perseid meteors,
the orbit of
periodic comet Swift-Tuttle is swept up by planet Earth.
plows through the atmosphere at nearly 60 kilometers
per second and is quickly vaporized at altitudes of 100 kilometers or so.
Perseid meteors are
often bright and colorful, like the one captured
in this sea and night skyscape.
and faint Milky Way the serene view
looks south and west across the Adriatic Sea, from the moonlit
toward the island of Brac.
Stars, Gas, and Dust Battle in the Carina Nebula
Chaos reigns in the Carina Nebula where massive stars form and die.
Striking and detailed,
of a portion of the famous nebula is a combination of light emitted by
(shown in red) and
(shown in blue).
Dramatic dark dust knots
and complex features revealed are
and radiation of Carina's massive and
One iconic feature of the
is the dark V-shaped dust lane
that occurs in the top half of the image.
The Carina Nebula
spans about 200
, lies about 7,500 light years distant,
and is visible with binoculars toward the
southern constellation of Carina
after the dust settles -- or is destroyed, and the gas dissipates -- or
, then only the
stars will remain
even the brightest ones.
Charon Flyover from New Horizons
What if you could fly over Pluto's moon Charon -- what might you see?
The New Horizons spacecraft did just this in 2015 July as it
zipped past Pluto
and Charon with cameras blazing.
The images recorded allowed for a digital reconstruction of much of
further enabling the creation of fictitious flights over Charon created from this data.
One such fanciful, minute-long, time-lapse video is
with vertical heights and colors of surface features digitally enhanced.
begins over a wide chasm that divides different types of
a chasm that might have formed when
You soon turn north and fly over a colorful depression dubbed
one hypothesis holds, is an
from an ancient impact.
continues over an
rich with never-before-seen craters, mountains, and crevices.
New Horizons spacecraft
has now been targeted at
2014 MU 69
which it should zoom past on New Year's Day 2019.
Detailed View of a Solar Eclipse Corona
Only in the fleeting darkness of a total solar eclipse is the
light of the solar corona easily visible.
Normally overwhelmed by the bright solar disk, the
sun's outer atmosphere
is an alluring sight.
But the subtle details and
in the corona's brightness, although discernible to the eye, are notoriously difficult to photograph.
however, using multiple images and digital processing, is a detailed image of the Sun's corona taken during the
2008 August total
Clearly visible are
and glowing caustics of an ever
changing mixture of hot gas and
Bright looping prominences
appear pink just above the Sun's
A similar solar corona might be
through clear skies in a
thin swath across the USA
total solar eclipse that occurs
just one week from tomorrow
A Day in the Life of a (mostly) Human Sundial
Have you ever wanted to be a gnomon?
Of course, a gnomon is the tall part of a
that casts a shadow.
The gnomon's shadow moves as the Sun moves across the sky,
indicating time by the shadow's position on the dial face.
, the Astronomy Group of the Progymnasium Rosenfeld
created a human sundial, each participant patiently playing the
role of the gnomon for 10 minutes.
In this timelapse video of their temporal
, one image was
taken every 20 seconds from 8 am until 4 pm Central European Summer Time.
Drawn on the ground are the dial hour marks calculated
to show the local time for that specific date.
Behind, the tower clock offers a time check.
Can you find the local time of solar noon?
(Hint: At solar noon the Sun is on the
The persistent group plans a repetition of the
human sundial performance next winter to compare the length
of the day and the altitude of the Sun.
A Total Solar Eclipse of Saros 145
A darkened sky holds bright planet Venus, the New Moon in
silhouette, and the shimmering
corona of the Sun
in this image of a total solar eclipse.
A composite of simultaneous telephoto and wide angle frames it was taken
in the path of totality 18 years ago,
1999, near Kastamonu, Turkey
That particular solar eclipse is a member of Saros 145.
from observations of the Moon's orbit,
Saros cycle predicts
when the Sun, Earth, and Moon will return to
the same geometry for a solar (or lunar) eclipse.
The Saros has a period of 18 years, 11 and 1/3 days.
Eclipses separated by one Saros period belong to the same numbered
Saros series and are very similar.
But the path of totality for consecutive solar eclipses
in the same Saros shifts across the Earth because the planet
rotates for an additional 8 hours during the cycle's
So the next solar eclipse
will also be a total eclipse,
and the narrow path of totality will track coast to coast across the
United States on
August 21, 2017
Night of the Perseids
will rain down near the peak of the annual
Perseid Meteor Shower.
Normally bright and colorful, the Perseid shower meteors are
produced by dust swept up by planet Earth from the orbit
of Comet Swift-Tuttle.
from a radiant in Perseus, above the horizon
in clear predawn skies.
Despite interfering light from August's waning gibbous moon,
this year's Perseids
will still be enjoyable,
especially if you can find yourself in an open space,
away from city lights, and in good company.
Frames used in this composite
capture bright Perseid meteors from the 2016 meteor
shower set against a starry background along the Milky Way,
with even the faint
just above center.
In the foreground, astronomers of all ages have gathered on a hill
above the Slovakian
village of Vrchtepla
August's Lunar Eclipse
August's Full Moon is framed in this sharp,
Captured before sunrise on August 8 from Sydney, Australia,
south is up and the Earth's dark, umbral shadow is at the left,
near the maximum phase of a
partial lunar eclipse
Kicking off the eclipse season, this time the Full Moon's
through Earth's shadow
was visible from the eastern hemisphere.
Up next is the much anticipated total solar eclipse of August 21.
Then, the New Moon's shadow track will include North America, the
narrow path of totality running
through the United States.
Density Waves in Saturn's Rings from Cassini
What causes the patterns in Saturn's rings?
The Cassini spacecraft
, soon ending its 13 years orbiting
has sent back another
Saturn's immense ring system
The physical cause for some of Saturn's
is not always understood.
The cause for the beautifully geometric type of ring structure
ring of Saturn
is surely a
A small moon systematically perturbing the orbits of
circling Saturn at slightly different distances causes such a
Also visible on the lower right of the image
a vertical wave
in ring particles also
caused by the gravity of a nearby moon.
Cassini's final orbits
are allowing a series of
novel scientific measurements
and images of the Solar System's
most grand ring system
Spiral Galaxy NGC 1512: The Inner Ring
Most galaxies don't have any rings -- why does this galaxy have two?
To begin, the bright band near
's center is a
a ring that surrounds the galaxy center and glows brightly with recently
Most stars and accompanying gas and
however, orbit the galactic center in a ring much further out --
here seen near the image edge.
This ring is called,
, the inner ring.
If you look closely, you will see this
the inner ring connects
ends of a diffuse
that runs horizontally across the galaxy.
These ring structures are thought to be caused by
own asymmetries in a drawn-out process called
of these galaxy asymmetries,
including the bar of stars,
cause gas and dust to fall from the inner ring to the nuclear ring,
enhancing this ring's rate of
Some spiral galaxies
also have a third ring -- an outer ring that
the galaxy even further out.
Milky Way and Exploding Meteor
Next weekend the
Perseid Meteor Shower
reaches its maximum.
Grains of icy rock will
streak across the sky
as they evaporate during entry into
These grains were shed from
result from the annual crossing of the Earth through
's orbit, and are
typically the most active
of the year.
Although it is hard to predict the level of activity in
any meteor shower
, in a clear dark sky an observer might see a
peak nearly a week after
and so some faint meteors will be lost to the lunar skyglow
in general are best be seen from a relaxing position
, away from lights.
is a meteor caught
during the 2015 Perseids above
next to the central band of our
Milky Way Galaxy
general theory of relativity, published over 100 years
ago, predicted the phenomenon of gravitational lensing.
And that's what gives these distant galaxies such a whimsical
through the looking glass
of X-ray and optical
image data from the Chandra and Hubble space telescopes.
Nicknamed the Cheshire Cat galaxy group, the group's two
large elliptical galaxies are suggestively framed by arcs.
The arcs are optical images
of distant background galaxies
lensed by the foreground group's total distribution
of gravitational mass.
Of course, that gravitational mass is dominated
by dark matter
The two large elliptical "eye" galaxies represent
the brightest members of their own galaxy groups which are merging.
Their relative collisional speed of nearly 1,350 kilometers/second
heats gas to millions of degrees producing the X-ray glow shown
in purple hues.
galaxy group mergers?
The Cheshire Cat
in the constellation Ursa Major, some 4.6 billion light-years away.
North North Temperate Zone Little Red Spot
On July 11, the Juno spacecraft once again swung near
the turbulent Jovian cloud tops.
On its seventh orbital closest approach this
brought Juno within 3,500 kilometers of
the Solar System's largest planetary atmosphere.
Near perijove the rotating
was able to record
stunning, clear view
of one of Jupiter's
About 8,000 kilometers in diameter, the anticyclonic storm system was
spotted in Jupiter's
North North Temperate Zone
in the 1990s.
That makes it about half the size of an older and better known
Jovian anticyclone, the Great Red Spot
but only a little smaller than planet Earth.
At times taking on reddish hues, the enormous storm system is
fondly known as a
Temperate Zone Little Red Spot
Pelican Nebula Close-up
The prominent ridge of emission featured in
is designated IC 5067.
Part of a larger emission region with a distinctive shape, popularly called
The Pelican Nebula
, the ridge spans about
10 light-years and follows the curve of the cosmic pelican's head and neck.
Fantastic, dark shapes inhabiting the view are clouds of cool gas and dust
energetic radiation from young, hot, massive stars.
But stars are also forming within the dark shapes.
Twin jets emerging from the tip of the long, dark tendril left of
center are the telltale signs of an embedded protostar cataloged as
indicating the presence of protostars are found
within the frame
The Pelican Nebula itself, also known as IC 5070,
is about 2,000 light-years away.
it, look northeast of bright
in the high flying
The Dust Monster in IC 1396
Is there a monster in IC 1396
Known to some as the
Elephant's Trunk Nebula
, parts of gas and
clouds of this
star formation region
may appear to take on foreboding forms, some
The only real
here, however, is a
bright young star
too far from
to hurt us.
from this star is eating away the dust of the dark
near the top of the
emitted from this star are also pushing away ambient gas and
Nearly 3,000 light-years
distant, the relatively faint
IC 1396 complex
covers a much larger region on the
sky than shown here, with an apparent width of more than 10