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APOD: 2026 March 23 – Light Pillars and Orion over Mohe
https://apod.nasa.gov/apod/image/2603/LightPillarsMohe_Dai_1080.jpg APOD: 2026 March 23 – Light Pillars and Orion over Mohe What's happening at the end of that street?
Pictured here are not auroras but light pillars, a phenomenon typically much closer.
In most places on Earth, a lucky viewer can see a Sun pillar,
a column of light appearing to extend up from the Sun
caused by flat fluttering ice-crystals reflecting sunlight from the upper atmosphere.
Usually, these ice crystals
evaporate before reaching the ground.
During freezing temperatures, however, flat
fluttering ice crystals may form near the ground and are sometimes known as a crystal fog.
These small ice crystals may then reflect not the Sun but ground lights.
The featured image captured not only numerous light pillars but also the iconic constellation of Orion, and was taken in Mohe, the northernmost city in China.
APOD: 2026 March 23 – Light Pillars and Orion over Mohe
https://apod.nasa.gov/apod/image/2603/LightPillarsMohe_Dai_1080.jpg APOD: 2026 March 23 – Light Pillars and Orion over Mohe What's happening at the end of that street?
Pictured here are not auroras but light pillars, a phenomenon typically much closer.
In most places on Earth, a lucky viewer can see a Sun pillar,
a column of light appearing to extend up from the Sun
caused by flat fluttering ice-crystals reflecting sunlight from the upper atmosphere.
Usually, these ice crystals
evaporate before reaching the ground.
During freezing temperatures, however, flat
fluttering ice crystals may form near the ground and are sometimes known as a crystal fog.
These small ice crystals may then reflect not the Sun but ground lights.
The featured image captured not only numerous light pillars but also the iconic constellation of Orion, and was taken in Mohe, the northernmost city in China.
Astronomy & Observing News – Sky & Telescope
NASA Has Cracked the Mystery of Asteroid Bennu’s Boulders
A new analysis of samples from the asteroid Bennu has solved a long-standing mystery: Cracks in the boulders strewn across its surface masquerade as sand.
The post NASA Has Cracked the Mystery of Asteroid Bennu’s Boulders appeared first on Sky & Telescope.
NASA Has Cracked the Mystery of Asteroid Bennu’s Boulders
A new analysis of samples from the asteroid Bennu has solved a long-standing mystery: Cracks in the boulders strewn across its surface masquerade as sand.
The post NASA Has Cracked the Mystery of Asteroid Bennu’s Boulders appeared first on Sky & Telescope.
Sky & Telescope
NASA Has Cracked the Mystery of Asteroid Bennu’s Boulders
A new analysis of samples from the asteroid Bennu has solved a long-standing mystery: Cracks in the boulders strewn across its surface masquerade as sand.
APOD: 2026 March 23 – Light Pillars and Orion over Mohe
What's happening at the end of that street?
https://apod.nasa.gov/apod/ap260323.html
What's happening at the end of that street?
https://apod.nasa.gov/apod/ap260323.html
Astronomy Picture of the Day RSS Feed
APOD: 2026 March 24 – A Gravity Map of Earth
APOD: 2026 March 24 – A Gravity Map of Earth Is gravity the same over the surface of the Earth?
No -- in some places you will feel slightly heavier than others.
The featured Earth map video shows in colors and
exaggerated highs and lows where the gravitational field of Earth
is relatively strong and weak.
A low spot, where you would feel slightly lighter,
can be seen just off the coast of India, in blue,
while a relative high occurs in the mountains of Chile in South America.
The cause of these irregularities does not always follow present surface features.
Scientists hypothesize that other important factors
lie in deep underground structures in Earth's mantle and may be related to the Earth's appearance in the distant past.
The featured map
was composed from data taken by NASA's twin GRACE
satellites that orbited the Earth from 2002 to 2017. GRACE mapped Earth's gravity by carefully tracking
tiny changes in the distance between the two satellites.
APOD: 2026 March 24 – A Gravity Map of Earth
APOD: 2026 March 24 – A Gravity Map of Earth Is gravity the same over the surface of the Earth?
No -- in some places you will feel slightly heavier than others.
The featured Earth map video shows in colors and
exaggerated highs and lows where the gravitational field of Earth
is relatively strong and weak.
A low spot, where you would feel slightly lighter,
can be seen just off the coast of India, in blue,
while a relative high occurs in the mountains of Chile in South America.
The cause of these irregularities does not always follow present surface features.
Scientists hypothesize that other important factors
lie in deep underground structures in Earth's mantle and may be related to the Earth's appearance in the distant past.
The featured map
was composed from data taken by NASA's twin GRACE
satellites that orbited the Earth from 2002 to 2017. GRACE mapped Earth's gravity by carefully tracking
tiny changes in the distance between the two satellites.
apod.nasa.gov
APOD: 2026 March 24 – A Gravity Map of Earth
A different astronomy and space science
related image is featured each day, along with a brief explanation.
related image is featured each day, along with a brief explanation.
Astronomy & Observing News – Sky & Telescope
Brown Dwarfs Dance Unexpected Tango
Two brown dwarfs are whipping around each other in a tight tango — an unexpected dance for objects that are not-quite-stars and not-quite-planets.
The post Brown Dwarfs Dance Unexpected Tango appeared first on Sky & Telescope.
Brown Dwarfs Dance Unexpected Tango
Two brown dwarfs are whipping around each other in a tight tango — an unexpected dance for objects that are not-quite-stars and not-quite-planets.
The post Brown Dwarfs Dance Unexpected Tango appeared first on Sky & Telescope.
Sky & Telescope
Brown Dwarfs Dance Unexpected Tango
Two brown dwarfs are whipping around each other in an unexpectedly tight dance for objects that are not-quite-stars and not-quite-planets.
Astronomy & Observing News – Sky & Telescope
Many Waters May Have Mixed on Mars
New analysis shows alkaline and acidic water may have mixed beneath the Martian surface, creating an environment that could theoretically have supported life.
The post Many Waters May Have Mixed on Mars appeared first on Sky & Telescope.
Many Waters May Have Mixed on Mars
New analysis shows alkaline and acidic water may have mixed beneath the Martian surface, creating an environment that could theoretically have supported life.
The post Many Waters May Have Mixed on Mars appeared first on Sky & Telescope.
Sky & Telescope
Many Waters May Have Mixed on Mars
Alkaline and acidic water may have mixed beneath the Martian surface, creating an environment that could theoretically have supported life.
APOD: 2026 March 25 – The Guardians of Rapa Nui beneath the Milky Way
In the words of today's astrophotographer, Rositsa Dimitrova,
https://apod.nasa.gov/apod/ap260325.html
In the words of today's astrophotographer, Rositsa Dimitrova,
https://apod.nasa.gov/apod/ap260325.html
🕊1
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APOD: 2026 March 26 –
https://apod.nasa.gov/apod/image/2603/GWTC4-Events-Poster-Landscape_1024.jpg APOD: 2026 March 26 – What is the sound of two black holes merging in deep space? Sound waves don't propagate in vacuum, but gravitational waves do.
In 2015 we were able to "hear" them for the first time and confirm one of Albert Einstein's theoretical predictions.
Each square on the grid of the featured image represents one of the gravitational wave detections announced so far by the LIGO-VIRGO-KAGRA Collaboration.
These plots show how the binary pair accelerates in their orbit around each other towards merger: the rising frequency effect is called a "chirp".
Although there are significantly more neutron stars than black holes, most of the detections are binary black hole mergers.
That happens because black holes are heavier and their signals are louder and can be seen farther away, resulting in more detections.
These events are rare, and we don't expect to see one close by in our Galaxy any time soon.
But they are happening continuously throughout the cosmos.
APOD: 2026 March 26 –
https://apod.nasa.gov/apod/image/2603/GWTC4-Events-Poster-Landscape_1024.jpg APOD: 2026 March 26 – What is the sound of two black holes merging in deep space? Sound waves don't propagate in vacuum, but gravitational waves do.
In 2015 we were able to "hear" them for the first time and confirm one of Albert Einstein's theoretical predictions.
Each square on the grid of the featured image represents one of the gravitational wave detections announced so far by the LIGO-VIRGO-KAGRA Collaboration.
These plots show how the binary pair accelerates in their orbit around each other towards merger: the rising frequency effect is called a "chirp".
Although there are significantly more neutron stars than black holes, most of the detections are binary black hole mergers.
That happens because black holes are heavier and their signals are louder and can be seen farther away, resulting in more detections.
These events are rare, and we don't expect to see one close by in our Galaxy any time soon.
But they are happening continuously throughout the cosmos.
Astronomy & Observing News – Sky & Telescope
Comet Break-Up Caught In Action
The Hubble Space Telescope caught a long-period comet breaking up just after it passed the Sun.
The post Comet Break-Up Caught In Action appeared first on Sky & Telescope.
Comet Break-Up Caught In Action
The Hubble Space Telescope caught a long-period comet breaking up just after it passed the Sun.
The post Comet Break-Up Caught In Action appeared first on Sky & Telescope.
Sky & Telescope
Comet Break-Up Caught In Action
The Hubble Space Telescope caught a comet — which came from the outer reaches of the solar system — breaking up just after it passed the Sun.
Astronomy & Observing News – Sky & Telescope
This Week's Sky at a Glance, March 27 – April 5
Winter's gone, but the Winter Triangle remains (for now). Trace out this gigantic asterism right after dark before it sinks. Jupiter glares inside its top.
The post This Week's Sky at a Glance, March 27 – April 5 appeared first on Sky & Telescope.
This Week's Sky at a Glance, March 27 – April 5
Winter's gone, but the Winter Triangle remains (for now). Trace out this gigantic asterism right after dark before it sinks. Jupiter glares inside its top.
The post This Week's Sky at a Glance, March 27 – April 5 appeared first on Sky & Telescope.
Sky & Telescope
This Week's Sky at a Glance, March 27 – April 5
The Winter Hexagon isn't gone yet. Trace out this huge asterism soon after dark before its bottom sinks away. Jupiter glares inside its top.
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APOD: 2026 March 27 – Hickson 44 in Leo
https://apod.nasa.gov/apod/image/2603/NGC3190-APOD1024.jpg APOD: 2026 March 27 – Hickson 44 in Leo
Scanning the skies for galaxies, Canadian astronomer
Paul Hickson and colleagues identified some 100 compact groups of galaxies,
now appropriately called Hickson Compact Groups.
The four prominent galaxies seen in this intriguing telescopic skyscape
are one such group, Hickson 44.
The Hickson 44 galaxy group is about 100 million light-years distant,
far beyond the foreground Milky Way stars,
toward the northern springtime constellation Leo.
The two spiral galaxies
in the center of the image are edge-on NGC 3190 with distinctive,
warped dust lanes, and S-shaped NGC 3187.
Along with the bright elliptical, NGC 3193 (left)
they are also known as Arp 316.
The spiral toward the lower right corner is NGC 3185,
the 4th member of the Hickson group.
Like other galaxies in Hickson groups,
these show signs of distortion and enhanced star formation,
evidence of a gravitational tug of war that will eventually result in
galaxy mergers on a cosmic timescale.
The merger process is
now understood to be a normal part of the evolution of
galaxies, including our own Milky Way.
For scale, NGC 3190
is about 75,000 light-years across at the estimated
distance of Hickson 44.
APOD: 2026 March 27 – Hickson 44 in Leo
https://apod.nasa.gov/apod/image/2603/NGC3190-APOD1024.jpg APOD: 2026 March 27 – Hickson 44 in Leo
Scanning the skies for galaxies, Canadian astronomer
Paul Hickson and colleagues identified some 100 compact groups of galaxies,
now appropriately called Hickson Compact Groups.
The four prominent galaxies seen in this intriguing telescopic skyscape
are one such group, Hickson 44.
The Hickson 44 galaxy group is about 100 million light-years distant,
far beyond the foreground Milky Way stars,
toward the northern springtime constellation Leo.
The two spiral galaxies
in the center of the image are edge-on NGC 3190 with distinctive,
warped dust lanes, and S-shaped NGC 3187.
Along with the bright elliptical, NGC 3193 (left)
they are also known as Arp 316.
The spiral toward the lower right corner is NGC 3185,
the 4th member of the Hickson group.
Like other galaxies in Hickson groups,
these show signs of distortion and enhanced star formation,
evidence of a gravitational tug of war that will eventually result in
galaxy mergers on a cosmic timescale.
The merger process is
now understood to be a normal part of the evolution of
galaxies, including our own Milky Way.
For scale, NGC 3190
is about 75,000 light-years across at the estimated
distance of Hickson 44.
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APOD: 2026 March 28 – Robert Goddard and Nell
https://apod.nasa.gov/apod/image/2603/goddardphotop9-1_800.jpg APOD: 2026 March 28 – Robert Goddard and Nell Robert H. Goddard,
considered the father of modern rocketry, was born in
Worcester Massachusetts in 1882.
As a 16 year old, Goddard read H.G. Wells' science fiction classic "War Of The Worlds"
and dreamed of space flight. By 1926
he had designed, built, and flown the world's first liquid fuel rocket. Launched 100 years ago,
on March 16, 1926 from his aunt Effie's farm in Auburn Massachusetts,
the rocket dubbed "Nell", rose to an
altitude of 41 feet in a flight that lasted about 2 1/2 seconds. In this posed photo
Goddard stands next to the 10 foot tall rocket, holding
the launch stand frame.
To achieve a stable flight without the need for fins, the rocket's heavy
motor was located at the top, fed by lines from
liquid oxygen and gasoline fuel tanks at the bottom.
Widely recognized as a gifted experimenter
and engineering genius,
his rockets were many years ahead
of their time.
Goddard was awarded over 200 patents in rocket technology,
most of them after his death in 1945.
A liquid fuel rocket constructed on principles developed by Goddard landed humans on the Moon in 1969.
APOD: 2026 March 28 – Robert Goddard and Nell
https://apod.nasa.gov/apod/image/2603/goddardphotop9-1_800.jpg APOD: 2026 March 28 – Robert Goddard and Nell Robert H. Goddard,
considered the father of modern rocketry, was born in
Worcester Massachusetts in 1882.
As a 16 year old, Goddard read H.G. Wells' science fiction classic "War Of The Worlds"
and dreamed of space flight. By 1926
he had designed, built, and flown the world's first liquid fuel rocket. Launched 100 years ago,
on March 16, 1926 from his aunt Effie's farm in Auburn Massachusetts,
the rocket dubbed "Nell", rose to an
altitude of 41 feet in a flight that lasted about 2 1/2 seconds. In this posed photo
Goddard stands next to the 10 foot tall rocket, holding
the launch stand frame.
To achieve a stable flight without the need for fins, the rocket's heavy
motor was located at the top, fed by lines from
liquid oxygen and gasoline fuel tanks at the bottom.
Widely recognized as a gifted experimenter
and engineering genius,
his rockets were many years ahead
of their time.
Goddard was awarded over 200 patents in rocket technology,
most of them after his death in 1945.
A liquid fuel rocket constructed on principles developed by Goddard landed humans on the Moon in 1969.
AstroNexus
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Astronomy Picture of the Day RSS Feed
APOD: 2026 March 29 – A Message from Earth
https://apod.nasa.gov/apod/image/2603/Message_Arecibo_960.jpg APOD: 2026 March 29 – A Message from Earth What are these Earthlings trying to tell us?
The featured message was broadcast from Earth
towards the globular star cluster M13 in 1974.
During the dedication of an upgrade to the Arecibo Observatory -
then the largest single radio telescope in the world -
a string of 1's and 0's representing the diagram was sent. This attempt at extraterrestrial communication
was mostly ceremonial - humanity regularly
broadcasts radio and television signals out into space accidentally.
Even were this message
received, M13 is so far away we would have to wait almost 50,000 years to hear an answer.
The featured message gives a few simple facts about humanity and its knowledge:
from left to right are numbers from one to ten, atoms including hydrogen and carbon,
some interesting molecules, DNA, a human with description, basics of our Solar System,
and basics of the sending telescope.
Several searches for extraterrestrial intelligence are currently underway.
APOD: 2026 March 29 – A Message from Earth
https://apod.nasa.gov/apod/image/2603/Message_Arecibo_960.jpg APOD: 2026 March 29 – A Message from Earth What are these Earthlings trying to tell us?
The featured message was broadcast from Earth
towards the globular star cluster M13 in 1974.
During the dedication of an upgrade to the Arecibo Observatory -
then the largest single radio telescope in the world -
a string of 1's and 0's representing the diagram was sent. This attempt at extraterrestrial communication
was mostly ceremonial - humanity regularly
broadcasts radio and television signals out into space accidentally.
Even were this message
received, M13 is so far away we would have to wait almost 50,000 years to hear an answer.
The featured message gives a few simple facts about humanity and its knowledge:
from left to right are numbers from one to ten, atoms including hydrogen and carbon,
some interesting molecules, DNA, a human with description, basics of our Solar System,
and basics of the sending telescope.
Several searches for extraterrestrial intelligence are currently underway.
APOD: 2026 March 29 – A Message from Earth
What are these Earthlings trying to tell us?
https://apod.nasa.gov/apod/ap260329.html
What are these Earthlings trying to tell us?
https://apod.nasa.gov/apod/ap260329.html