December 19th to December 25th Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

Click on the hyper link for each day you would like to see.

2022 December 25: Geminids and the Mittens
2022 December 24: Comet 2022 E3 ZTF
2022 December 23: Cassini Looks Out from Saturn
2022 December 22: NGC 1365: Majestic Island Universe
2022 December 21: Sun Halo at Sixty-three Degrees North
2022 December 20: Thor’s Helmet
2022 December 19: The Tadpole Nebula in Gas and Dust

December 13th to 18th Astronomy Picture of the Day

(Today starts the weekly pictures for the Astronomy Picture of the Day. We will continue posting this weekly. Just click on the hyperlink next to the date for the pictures you want to see.)

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 December 18: The 25 Brightest Stars in the Night Sky
2022 December 17: Apollo 17 VIP Site Anaglyph
2022 December 16: The Geminid
2022 December 15: Full Moon, Full Mars
2022 December 14: Lunar Dust and Duct Tape
2022 December 13: An Artful Sky over Lofoten Islands

December 12 Astronomy Picture of the Day

Starting next Sunday, DCEMBER 25 the Astronomy Picture of the Day is only going to be posted every Sunday for the entire last week of Pictures.

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 December 12

An Unusual Globule in IC 1396

Image Credit & Copyright: Bernard Miller

Explanation: Is there a monster in IC 1396? Known to some as the Elephant’s Trunk Nebula, parts of gas and dust clouds of this star formation region may appear to take on foreboding forms, some nearly human. The only real monster here, however, is a bright young star too far from Earth to hurt us. Energetic light from this star is eating away the dust of the dark cometary globule near the top of the featured imageJets and winds of particles emitted from this star are also pushing away ambient gas and dust. 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 full moons.

December 10 Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 December 10

America and the Sea of Serenity

Gene CernanApollo 17NASA; Anaglyph by Patrick Vantuyne

Explanation: Get out your red/blue glasses and check out this stereo view of another world. Fifty years ago the scene was recorded by Apollo 17 mission commander Eugene Cernan on December 11, 1972, one orbit before descending to land on the Moon. The stereo anaglyph was assembled from two photographs (AS17-147-22465, AS17-147-22466) captured from his vantage point on board the Lunar Module Challenger as he and Dr. Harrison Schmitt flew over Apollo 17’s landing site in the Taurus-Littrow Valley. The broad, sunlit face of the mountain dubbed South Massif rises near the center of the frame, above the dark floor of Taurus-Littrow to its left. Piloted by Ron Evans, the Command Module America is visible in orbit in the foreground against the South Massif’s peak. Beyond the mountains, toward the lunar limb, lies the Moon’s Mare Serenitatis.

December 9 Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 December 9

Mars Rises above the Lunar Limb

Image Credit & CopyrightTom Glenn

Explanation: On the night of December 7 Mars wandered near the Full Moon. In fact the Red Planet was occulted, passing behind the Moon, when viewed from locations across Europe and North America. About an hour after disappearing behind the lunar disk Mars reappears in this stack of sharp video frames captured from San Diego, planet Earth. With the Moon in the foreground Mars was a mere 82 million kilometers distant, near its own opposition. Full Moon and full Mars were bright enough provide the spectacular image with no exposure adjustments necessary. In the image Mars appears to rise just over ancient, dark-floored, lunar crater Abel very close to the southeastern edge of the Moon’s near side. Humboldt is the large impact crater to its north (left).

December 8 Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 December 8

Orion and the Ocean of Storms

Image Credit: NASAArtemis 1

Explanation: A camera on board the uncrewed Orion spacecraft captured this view on December 5 as Orion approached its return powered flyby of the Moon. Below one of Orion’s extended solar arrays lies dark, smooth, terrain along the western edge of the Oceanus Procellarum. Prominent on the lunar nearside Oceanus Procellarum, the Ocean of Storms, is the largest of the Moon’s lava-flooded maria. The lunar terminator, shadow line between lunar night and day, runs along the left of the frame. The 41 kilometer diameter crater Marius is top center, with ray crater Kepler peeking in at the edge, just right of the solar array wing. Kepler’s bright rays extend to the north and west, reaching the dark-floored MariusOf course the Orion spacecraft is now headed toward a December 11 splashdown in planet Earth’s water-flooded Pacific Ocean.

December 7 Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 December 7

NGC 7293: The Helix Nebula

Image Credit & Copyright: Tommaso Stella

Explanation: A mere seven hundred light years from Earth, toward the constellation Aquarius, a sun-like star is dying. The dying star’s last few thousand years have produced the Helix Nebula (NGC 7293), a well studied and nearby example of a Planetary Nebula, typical of this final phase of stellar evolution. Combining narrow band image data from emission lines of hydrogen atoms in red and oxygen atoms in blue-green hues, it shows tantalizing details of the Helix, including its bright inner region about 3 light-years across. The white dot at the Helix’s center is this Planetary Nebula’s hot, central star. A simple looking nebula at first glance, the Helix is now understood to have a surprisingly complex geometry.

December 6 Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 December 6

M16: A Star Forming Pillar from Webb

Image Credit: NASAESACSASTScIProcessing & Copyright: Mehmet Hakan Özsaraç

Explanation: What’s happening inside this interstellar mountain? Stars are forming. The mountain is actually a column of gas and dust in the picturesque Eagle Nebula (M16). A pillar like this is so low in density that you could easily fly though it — it only appears solid because of its high dust content and great depth. The glowing areas are lit internally by newly formed stars. These areas shine in red and infrared light because blue light is scattered away by intervening interstellar dust. The featured image was captured recently in near-infrared light in unprecedented detail by the James Webb Space Telescope (JWST), launched late last year. Energetic light, abrasive winds, and final supernovas from these young stars will slowly destroy this stellar birth column over the next 100,000 years.

 

Astrophysicists: Browse 2,900+ codes in the Astrophysics Source Code Library

December Solstice: Longest and Shortest Day of the Year

Solstice and Equinox in the Northern Hemisphere

Solstice and Equinox in the Southern Hemisphere

There are two solstices every year: one in December and one in June. The December solstice marks the shortest day north of the equator and the longest day in the south.

Sun Reaches Most Southerly Point

The December solstice is the moment the Sun is directly above the Tropic of Capricorn in the Southern Hemisphere. This is the southernmost latitude it reaches during the year. After the solstice, it begins moving north again.

Solstice Local Time & Date

In Plainfield, Illinois, USA: Wednesday, December 21, 2022 at 3:48 pm CST (Change location)
This corresponds to Wednesday, December 21, 2022 at 21:48 UTC.

Sun rise/set and day length around this solstice

Solstice countdown

Local times for this solstice worldwide

Solstice Day and Night Map

Shortest Day in the North

Since the Northern Hemisphere is tilted away from the Sun in December, it receives less sunlight during the course of a day. At the solstice, the North Pole’s tilt away from the Sun is greatest, so this event marks the shortest day of the year north of the equator.

This effect is greatest in locations that are farther away from the equator. In tropical areas, the shortest day is just a little shorter than 12 hours; in the temperate zone, it is significantly shorter; and places within the Arctic Circle experience polar night, when the Sun does not rise at all.

Longest Day in the South

Conversely, the day of the December solstice is the longest day of the year in the Southern Hemisphere. Here, too, the effect is greater the farther a location is away from the equator.

Places within the Antarctic Circle experience Midnight Sun, when the Sun does not set at night.

What Does “Solstice” Mean?

During the course of a year, the subsolar point—the spot on the Earth’s surface directly beneath the Sun—slowly moves along a north-south axis. Having reached its northernmost point at the June solstice, it starts moving southward until it crosses the equator on the day of the September equinox. At the December solstice, which marks the southernmost point of its journey, it stops again to start its journey back toward the north.

This is how the solstices got their name: the term comes from the Latin words sol and sistere, meaning “Sun” and “to stand still”.

Initially, the naming arose from observations of how the Sun’s apparent path across the sky changes slightly from one day to the next, which is caused by the same process as the subsolar point’s movement described above.

In the months leading up to the December solstice, the position of sunrise and sunset creeps southward. On the day of the solstice, it reaches its southernmost point. After that, the daily path of the Sun across the sky begins to creep northward again.

Why Does the Sun Move North and South?

The subsolar point moves north and south during the year because the Earth’s axis is tilted at an angle of about 23.4° in relation to the ecliptic, an imaginary plane created by Earth’s path around the Sun. In June, the Northern Hemisphere is tilted toward the Sun, and the subsolar point is north of the equator. As the Earth travels toward the opposite side of its orbit, which it reaches in December, the Southern Hemisphere gradually receives more sunlight, and the subsolar point travels south.

The Solstices and the Seasons

The December solstice marks the start of winter in the Northern Hemisphere and the start of summer in the Southern Hemisphere, according to one definition.

Sunrise and Sunset Times Lag Behind

The shortest day of the year is commonly associated with the latest sunrise and earliest sunset of the year. However, in most locations, the earliest sunset happens a few days before the solstice, while the latest sunrise occurs some days after itFind out why

The December Solstice in the Calendar …

Click here to read the rest of this article by timeanddate.com

Astronomy Picture of the Day for December to Today

You can use these hyperlinks to view each day’s pictures

2022 December 05: Pleiades: The Seven Sisters Star Cluster
2022 December 04: Video: Powers of Ten
2022 December 03: Stereo Mars near Opposition
2022 December 02: Merging Galaxy Pair IIZw096
2022 December 01: Artemis 1: Flight Day 13

December 2 Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 December 2

A merging galaxy pair cavort in this image captured by the NASA/ESA/CSA James Webb Space Telescope. This pair of galaxies, known to astronomers as II ZW 96, is roughly 500 million light-years from Earth and lies in the constellation Delphinus, close to the celestial equator. As well as the wild swirl of the merging galaxies, a menagerie of background galaxies are dotted throughout the image.The two galaxies are in the process of merging and as a result have a chaotic, disturbed shape. The bright cores of the two galaxies are connected by bright tendrils of star-forming regions, and the spiral arms of the lower galaxy have been twisted out of shape by the gravitational perturbation of the galaxy merger. It is these star-forming regions that made II ZW 96 such a tempting target for Webb; the galaxy pair is particularly bright at infrared wavelengths thanks to the presence of the star formation. This observation is from a collection of Webb measurements delving into the details of galactic evolution, in particular in nearby Luminous Infrared Galaxies such as II ZW 96. These galaxies, as the name suggests, are particularly bright at infrared wavelengths, with luminosities more than 100 billion times that of the Sun. An international team of astronomers proposed a study of complex galactic ecosystems — including the merging galaxies in II ZW 96 — to put Webb through its paces soon after the telescope was commissioned. Their chosen targets have already been observed with ground-based telescopes and the NASA/ESA Hubble Space Telescope, which will provide astronomers with insights into Webb’s ability to unravel the details of complex galactic environments. Webb captured this merging galaxy pair with a pair of its cutting-edge instruments; NIRCam — the Near-InfraRed Camera — and MIRI, the Mid-InfraRed Instrument. If you are interested in exploring the differences between Hubble and Webb’s observations of II ZW 96, you can do so here.MIRI was contributed by ESA an

Merging Galaxy Pair IIZw096

Image Credit: ESA/Webb, NASA & CSA, L. Armus, A. Evans

Explanation: Bright at infrared wavelengths, this merging galaxy pair is some 500 million light-years away toward the constellation Delphinus. The cosmic mashup is seen against a background of even more distant galaxies, and occasional spiky foreground stars. But the galaxy merger itself spans about 100,000 light-years in this deep James Webb Space Telescope image. The image data is from Webb’s Near-InfraRed Camera (NIRCam) and Mid-InfraRed Instrument (MIRI). Their combined, sharp infrared view follows galactic scale restructuring in the dusty merger’s wild jumble of intense star forming regions and distorted spiral arms

December 1 Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 December 1

DCIM100GOPROGOPR1346.

Artemis 1: Flight Day 13

Image Credit: NASAArtemis 1

Explanation: On flight day 13 (November 28) of the Artemis 1 mission the Orion spacecraft reached its maximum distance from Earth. In fact, over 430,000 kilometers from Earth its distant retrograde orbit also put Orion nearly 70,000 kilometers from the Moon. In the same field of view in this video frame from flight day 13, planet and large natural satellite even appear about the same apparent size from the uncrewed spacecraft’s perspective. Today (December 1) should see Orion depart its distant retrograde orbit. En route to planet Earth it will head toward a second powered fly by of the Moon. Splashdown on the home world is expected on December 11.

November 30 Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 November 30

The Light, the Dark, and the Dusty

Image Credit & CopyrightAnthony Quintile

Explanation: This colorful skyscape spans about four full moons across nebula rich starfields along the plane of our Milky Way Galaxy in the royal northern constellation Cepheus. Near the edge of the region’s massive molecular cloud some 2,400 light-years away, bright reddish emission region Sharpless (Sh) 155 is at the center of the frame, also known as the Cave Nebula. About 10 light-years across the cosmic cave’s bright walls of gas are ionized by ultraviolet light from the hot young stars around it. Dusty reflection nebulae, like vdB 155 to the right, and dense obscuring clouds of dust also abound on the interstellar canvas. Astronomical explorations have revealed other dramatic signs of star formation, including the bright reddish fleck of Herbig-Haro (HH) 168. Below and right of center, the Herbig-Haro object emission is generated by energetic jets from a newborn star.

November 29 Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 November 29

The Gum Nebula Supernova Remnant

Image Credit & Copyright: Victor Lima

Explanation: Because the Gum Nebula is the closest supernova remnant, it is actually hard to see. Spanning 40 degrees across the sky, the nebula appears so large and faint that it is easily lost in the din of a bright and complex background. The Gum Nebula is highlighted nicely in red emission toward the right of the featured wide-angle, single-image photograph taken in late May. Also visible in the frame are the Atacama Desert in Chile in the foreground, the Carina Nebula in the plane of our Milky Way galaxy running diagonally down from the upper left, and the neighboring Large Magellanic Cloud (LMC) galaxy. The Gum Nebula is so close that we are much nearer the front edge than the back edge, each measuring 450 and 1500 light years respectively. The complicated nebula lies in the direction of the constellations of Puppis and Vela. Oddly, much remains unknown about the Gum Nebula, including the timing and even number of supernova explosions that formed it.

November 28 Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 November 28

Leonid Meteors Through Orion

Image Credit & Copyright: Luo Hongyang

Explanation: Where will the next meteor appear? Even during a meteor shower, it is practically impossible to know. Therefore, a good way to enjoy a meteor shower is to find a place where you can sit comfortably and monitor a great expanse of dark sky. And it may be satisfying to share this experience with a friend. The meteor shower depicted was the 2022 Leonids which peaked earlier this month, and the view is from HainanChina looking out over the South China Sea. Meteor streaks captured over a few hours were isolated and added to a foreground image recorded earlier. From this place and time, Leonid meteors that trace back to the constellation of Leo were seen streaking across other constellations including Orion. The bright red planet Mars appears near the top of the image. Bonding over their love of astronomy, the two pictured meteor enthusiasts, shown celebrating their common birthday this month, are now married.

 

November 27, 2022 Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 November 27

Supernumerary Rainbows over New Jersey

Image Credit & Copyright: John Entwistle

Explanation: Yes, but can your rainbow do this? After the remnants of Hurricane Florence passed over the Jersey Shore, New JerseyUSA in 2018, the Sun came out in one direction but something quite unusual appeared in the opposite direction: a hall of rainbows. Over the course of a next half hour, to the delight of the photographer and his daughter, vibrant supernumerary rainbows faded in and out, with at least five captured in this featured single shot. Supernumerary rainbows only form when falling water droplets are all nearly the same size and typically less than a millimeter across. Then, sunlight will not only reflect from inside the raindrops, but interfere, a wave phenomenon similar to ripples on a pond when a stone is thrown in. In fact, supernumerary rainbows can only be explained with waves, and their noted existence in the early 1800s was considered early evidence of light’s wave nature.

Your Sky Surprise: What picture did APOD feature on your birthday? (post 1995)

November 26 Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 November 26

Saturn at Night

NASAJPL-CaltechSpace Science InstituteMindaugas Macijauskas

Explanation: Saturn is still bright in planet Earth’s night skies. Telescopic views of the distant gas giant and its beautiful rings often make it a star at star parties. But this stunning view of Saturn’s rings and night side just isn’t possible from telescopes closer to the Sun than the outer planet. They can only bring Saturn’s day into view. In fact, this image of Saturn’s slender sunlit crescent with night’s shadow cast across its broad and complex ring system was captured by the Cassini spacecraft. A robot spacecraft from planet Earth, Cassini called Saturn orbit home for 13 years before it was directed to dive into the atmosphere of the gas giant on September 15, 2017. This magnificent mosaic is composed of frames recorded by Cassini’s wide-angle camera only two days before its grand final plunge. Saturn’s night will not be seen again until another spaceship from Earth calls.

November 25 Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 November 25

NGC 6744: Extragalactic Close-Up

Image Credit: NASAESA, and the LEGUS team

Explanation: Beautiful spiral galaxy NGC 6744 is nearly 175,000 light-years across. That’s larger than the Milky Way. It lies some 30 million light-years distant in the southern constellation Pavo, with its galactic disk tilted towards our line of sight. This Hubble close-up of the nearby island universe spans about 24,000 light-years or so across NGC 6744’s central region. The Hubble view combines visible light and ultraviolet image data. The giant galaxy’s yellowish core is dominated by the visible light from old, cool stars. Beyond the core are star-forming regions and young star clusters scattered along the inner spiral arms. NGC 6744’s young star clusters are bright at ultraviolet wavelengths, shown in blue and magenta hues. Spiky stars scattered around the frame are foreground stars and well within our own Milky Way.

November 24, Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 November 24

Lynds Dark Nebula 1251

Image Credit & Copyright: Stefano Attalienti

Explanation: Stars are forming in Lynds Dark Nebula (LDN) 1251. About 1,000 light-years away and drifting above the plane of our Milky Way galaxy, the dusty molecular cloud is part of a complex of dark nebulae mapped toward the Cepheus flare region. Across the spectrum, astronomical explorations of the obscuring interstellar clouds reveal energetic shocks and outflows associated with newborn stars, including the telltale reddish glow from scattered Herbig-Haro objects hiding in the image. Distant background galaxies also lurk on the scene, almost buried behind the dusty expanse. This alluring view spans over four full moons on the sky, or 35 light-years at the estimated distance of LDN 1251.

November 23 Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2022 November 23

Earthset from Orion

Image Credit: NASAArtemis 1

Explanation: Eight billion people are about to disappear in this snapshot from space. Taken on November 21, the sixth day of the Artemis 1 mission, their home world is setting behind the Moon’s bright edge as viewed by an external camera on the outbound Orion spacecraft. The Orion was headed for a powered flyby that took it to within 130 kilometers of the lunar surface. Velocity gained in the flyby maneuver will be used to reach a distant retrograde orbit around the Moon. That orbit is considered distant because it’s another 92,000 kilometers beyond the Moon, and retrograde because the spacecraft will orbit in the opposite direction of the Moon’s orbit around planet Earth. Orion will enter its distant retrograde orbit on Friday, November 25. Swinging around the Moon, Orion will reach a maximum distance (just over 400,000 kilometers) from Earth on Monday November 28 exceeding a record set by Apollo 13 for most distant spacecraft designed for human space exploration.