The bright waxing gibbous moon will pass the faint but distinct Circlet asterism in Pisces the Fish on the evenings of December 19 and 20, 2023. The moon and the Circlet will be visible as darkness falls and will set after midnight.

December 19: 1st quarter moon

The instant of 1st quarter moon will fall at 18:39 UTC (12:39 p.m. CST), on December 19, 2023. The 1st quarter moon rises around noon your local time and sets around midnight.

EarthSky Minute, December 18-21, 2023

See what’s in store for in the sky for the coming days.

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EarthSky Minute, moon phases December 2023

December 21 and 22 evenings: Moon near Jupiter

On the evenings of December 21 and 22, 2023, the waxing gibbous moon will glow near the bright planet Jupiter. The moon and Jupiter will set several hours after midnight.

December solstice: December 21-22

The December solstice is at 3:27 UTC on December 22, 2023 (9:27 p.m. December 21 CST). Winter arrives in the Northern Hemisphere and summer arrives in the Southern Hemisphere.

December 22: Mercury will pass between Earth and the sun

Mercury will reach the point in its orbit known as inferior conjunction – when it passes between Earth and the sun – at 19 UTC on December 22.

Our charts are mostly set for the northern half of Earth. To see a precise view – and time – from your location, try Stellarium Online.

December 22-23 mornings: Ursid meteor shower

The predicted peak of the Ursid meteor shower is on the early mornings of December 22 and 23, 2023. The best time to watch is before dawn and after the waxing gibbous moon has slipped below the horizon.

December 23 and 24 evenings: Moon near the Pleiades

The bright waxing gibbous moon will pass the Pleiades star cluster on the evenings of December 23 and 24, 2023. The Pleiades is also known as the Seven Sisters or Messier 45 and appears as a glittering, bluish cluster of stars in the constellation Taurus the Bull. The moon and Pleiades will cross the sky together until about an hour before sunrise.

December 25 all night: Moon near Capella, Aldebaran and Betelgeuse

December 25, 2023, the bright waxing gibbous moon will lie near a trio of bright stars. It’ll be near the fiery orange star Aldebaran of Taurus the Bull and Orion’s mighty red supergiant star Betelgeuse. The bright golden star is Capella of the constellation Auriga the Charioteer. If you catch Capella low on the horizon, it may be flashing like a small disco ball. You can follow them all night until sunrise.

December 26-27, all night: Full Moon

The instant of full moon will fall at 0:33 UTC on December 27, 2023 (6:33 p.m. CST December 26).

Our charts are mostly set for the northern half of Earth. To see a precise view – and time – from your location, try Stellarium Online.

December 26 and 27 evenings: Moon near Castor and Pollux

On the evening of December 26, 2023, the full moon will pass Castor and Pollux, the twin stars of Gemini. Then on the evening of December 27, the waning gibbous moon will be closer to the Twin Stars of Gemini. They’ll rise a few hours after sunset and be visible traveling across the sky all night.

December 29 morning: Moon near the Beehive

For the second time this month, the moon will slide by the famous – but faint – Beehive star cluster. This time it will be a waning gibbous moon on the morning of December 29, 2023. You will need binoculars to spot the dozens of stars in the busy Beehive star cluster. Also nearby will be the twin stars, Castor and Pollux, in the constellation Gemini. They’ll rise late the night before and be high in the morning sky.

December 30 and 31 mornings: Moon near the Sickle

On the mornings of December 30 and 31, 2023, the waning gibbous moon will float near Regulus, marking the bottom of the backward question mark asterism called the Sickle. Regulus is the brightest star in Leo the Lion. And the moon will lie close to Regulus on the final morning of 2023. They’ll rise late in the evening the night before and be high in the morning sky.

Our charts are mostly set for the northern half of Earth. To see a precise view – and time – from your location, try Stellarium Online.

Planets in December 2023

December mornings: Venus

The blazing light of Venus will continue to dominate the morning sky through the end of the year. However, it will be sinking lower each morning after it reached its greatest elongation from the sun in October. Luckily, it will rise early enough to see it in dark skies. Venus will begin the month at -4.2 magnitude and will dim slightly as it recedes from Earth, ending the month at -4.1 magnitude. A lovely waning crescent moon will join Venus on the morning of December 9, 2023, when they appear about 4 degrees apart. Also, Venus will appear close to the star Spica at the beginning of the month, and then they drift apart more each morning. Venus begins the month in the constellation Virgo the Maiden and will move into Libra the Scales by mid-month. Then by month’s end, it will be in the constellation Scorpius the Scorpion.

December most of the night: Jupiter

Bright Jupiter will draw your attention most of the night. It will be very obvious in the east at sunset and will be visible until a few hours before dawn. It will shine near the pretty Pleiades star cluster in the constellation Taurus the Bull. Jupiter reached its closest point to the Earth in early November. And it reached opposition overnight on November 2-3, 2023, when we flew between it and the sun. So, as Jupiter recedes from Earth, it’ll fade a bit in our sky. It will lie in the dim constellation Aries the Ram. It will shine at -2.7 magnitude by month’s end. The waxing gibbous moon will float by Jupiter on December 22, 2023.

December evenings: Saturn

Golden Saturn will shine in the southwest after sunset during December. It will be in the dim constellation Aquarius the Water Bearer. Our solar system’s beautiful ringed planet will be fading a bit this month as it recedes from Earth and will shine at +0.9 magnitude for most of the month. Saturn will be a little brighter than the nearby lonely star, Fomalhaut, which shines around 1st magnitude. The waxing gibbous moon will visit Saturn on the evenings of December 17, 2023. Saturn will set by mid-evening your local time this month.

December evenings: Mercury

Mercury will be emerging low in the morning sky the last few days of the year on its way to its first greatest morning elongation of 2024.

Where’s Mars?

It’s too close to the sun in the morning sky to be visible for the rest of 2023. It’ll be back next year.

Thank you to all who submit images to EarthSky Community Photos! View community photos here. We love you all. Submit your photo here.

Looking for a dark sky? Check out EarthSky’s Best Places to Stargaze.

Sky dome maps for visible planets and night sky

The sky dome maps come from master astronomy chart-maker Guy Ottewell. You’ll find charts like these for every month of 2023 in his Astronomical Calendar.

Guy Ottewell explains sky dome maps

Heliocentric solar system planets

The sun-centered charts come from Guy Ottewell. You’ll find charts like these for every month of 2023 in his Astronomical Calendar.

Guy Ottewell explains heliocentric charts.

Some resources to enjoy

For more videos of great night sky events, visit EarthSky’s YouTube page.

Watch EarthSky’s video about Two Great Solar Eclipses Coming Up

Don’t miss anything. Subscribe to daily emails from EarthSky. It’s free!

Visit EarthSky’s Best Places to Stargaze to find a dark-sky location near you.

Post your own night sky photos at EarthSky Community Photos.

Translate Universal Time (UTC) to your time.

See the indispensable Observer’s Handbook, from the Royal Astronomical Society of Canada.

Visit Stellarium-Web.org for precise views from your location.

Almanac: Bright Planets (rise and set times for your location).

Visit TheSkyLive for precise views from your location.

Bottom line: Visible planets: Venus dominates the morning sky. Jupiter is visible most of the night, Saturn sets late evenings and Mercury is low on the western horizon. Visible planets and night sky, here!

The post Visible planets and night sky for December first appeared on EarthSky.

Fornax the Furnace lies high in the Southern Hemisphere sky on December evenings. In fact, it’s tucked in a bend of the constellation Eridanus the River. None of the stars in Fornax is particularly bright, but the constellation does hold some wonderful gems in its darker depths: at least six star systems with exoplanets, the Fornax Dwarf galaxy (a satellite galaxy of the Milky Way), the Fornax Cluster of galaxies, a cosmic filament showing the largest rotation in the universe and the amazing Hubble Ultra Deep Field image. By the way, Fornax is one of 14 constellations that Nicolas Louis de Lacaille named in the mid-1700s.

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Fornax the Furnace and its stars

Deep in the Southern Hemisphere, Fornax the Furnace is a devilish constellation to find because of its dim stars. Its brightest star, Alpha Fornacis, has a magnitude of only 3.9. This star lies about 46 light-years from Earth. The second brightest star, Beta Fornacis, with a magnitude of 4.4, lies 169 light-years away. Sometimes people point to a third star of Fornax in order to trace out a flattened triangle in this region of space. The third brightest star is Nu Fornacis with magnitude 4.6, 357 light-years away.

So far, scientists have found six star systems in Fornax to be harboring planets. One of the stars, HR 858 at magnitude 6.3, is just barely visible to the unaided eye for those with good eyesight. The Transiting Exoplanet Survey Satellite TESS found at least three exoplanets orbiting this star in 2019.

Fornax Dwarf, the satellite galaxy

One of the satellite galaxies of the Milky Way lies in the direction of Fornax the Furnace. The Fornax Dwarf is an elliptical collection of stars with six notable globular clusters. One of its globular clusters, NGC 1049, was discovered by John Herschel on October 19, 1835. But the galaxy itself wasn’t discovered until more than 100 years later, by Harlow Shapley in 1938.

Galaxies clusters in Fornax the Furnace

Also, one of the closest galaxy clusters to our Milky Way is the Fornax Cluster. It lies 62 million light-years away in the direction of Fornax and spills over into Eridanus the River. The brightest galaxy in the cluster, NGC 1316, shines at magnitude 8.5, meaning that you can pick it up with binoculars from under dark skies. NGC 1316, which also goes by the name Fornax A, is the fourth brightest radio source in the sky.

Hubble Ultra Deep Field

Since this is an “empty” region of sky, giving us a view into the wider universe with few obstructions, the Hubble Space Telescope aimed in the direction of Fornax to take an image of the early universe in 2003. The Hubble Ultra Deep Field shows a small piece of the universe packed with galaxies, looking back in space and time as far as 13 billion years ago.

Largest rotation in the universe

The galaxies in our universe are strung together in long filaments and webs, creating the grand structure of the cosmos. Scientists have detected that one enormous filament of galaxies is rotating. These corkscrewing galaxies, located in the direction of Fornax, display the largest rotation in the universe.

Bottom line: Fornax the Furnace is a constellation in the Southern Hemisphere that appears as a few dim stars to the unaided eye but is harboring galaxies, from one orbiting the Milky Way to some at the edge of the universe.

The post Fornax the Furnace: A dim constellation with galaxies galore first appeared on EarthSky.

Rain that doesn’t reach the ground

Have you seen clouds that are pouring rain … but the rain never reaches the ground? Meteorologists call this rain by the name virga. You see virga in places where the air is dry, and often warm. The rain evaporates as it falls, before hitting Earth. So you might see virga in a desert, or at high altitudes, for example, in the western U.S. and Canadian prairies, the Middle East, Australia and North Africa. Virga isn’t rare. But it’s delicate and very beautiful. Maybe you’ve seen it lots of times, but never knew it had a name?

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Virga on radar

Sometimes, when you’re looking at your weather app, you might see what looks like rain or snow on the radar, but nothing is falling outside. Instead, look up at the clouds and see if you can spot virga. The radar is picking up precipitation in the air which is just not reaching the ground. As weather.gov says:

The radar isn’t lying, rather, the the rain or snow is not hitting the ground. If you have a dry air mass in place in the low levels, sometimes rain cannot completely penetrate that dry layer before it evaporates.

Do you want to learn to identify virga when you see it? Check out the photos on this page from our global EarthSky community. Once you acquaint yourself with the variations of virga, you’ll be able to spot it in your own sky. If you capture a photo of virga, submit it to us!

Photos of virga from EarthSky’s community

More photos

Bottom line: Learn what virga is and how it forms, and see great photos to help you learn how to identify it yourself!

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The post Virga is rain that doesn’t reach the ground first appeared on EarthSky.

An expedition to see emperor penguins

EarthSky friend Eliot Herman took a trip to the Antarctic in late November. After more than 30 hours of flights, he and his wife reached Antarctica, where they got to observe a resident colony of emperor penguins. He shared his fantastic photos with us, and reported from the southern reaches of the world:

We flew to the interior and landed on an ice runway, then to a camp and finally ski-plane to the emperor penguin colony at Atka Bay. With reports of the penguins having reproductive problems, I was concerned about what I would see. The colony we saw had a large population of healthy chubby chicks. A photographer’s dream trip.

Eliot said the travel to get to and from Antarctica was long, but one he has wanted to do for many years. He said:

Seeing the emperors is special, few people do, only a very few of the cruise boats have a chance to go that deep into the Weddell Sea. They often fail, so the number of tourists who see the emperors each year cannot be more than 100 to 200.

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Photos of the expedition

More emperor penguins

The heroes of the trip

See more images of the expedition at Eliot’s Flickr page

Read more on why emperor penguins are endangered

Bottom line: EarthSky friend Eliot Herman took a trip to the Antarctic, where he had the opportunity to visit emperor penguins in their colony. Read his report and enjoy his amazing images.

The post Emperor penguins: A report from the Antarctic first appeared on EarthSky.

World’s largest iceberg headed to warm waters

The largest iceberg in the world is a behemoth known as A23a. It spans some 40 miles (65 km) across. It’s 1,312 feet (400 m) thick. It calved from Antarctica’s Filchner Ice Shelf decades ago, in August 1986. But almost immediately it grounded on the seafloor, and so was locked in place for decades afterwards. The iceberg had been creeping forward starting in 2020, likely due to melting from below the waterline. And then, in late November 2023, the British Antarctic Survey said the iceberg was officially on the move. It’s currently heading out of the Weddell Sea and will enter into the Southern Atlantic, where, eventually, it’ll melt and disappear.

Space satellites are tracking the movement of the iceberg, including NOAA-21, a new weather satellite that just became operational this year. This satellite circles the globe 14 times a day in a polar orbit. NOAA-21 took the image of the iceberg above on December 7, 2023.

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Iceberg headed toward extinction

As the iceberg enters warmer waters, it’ll undergo melting. Still, with an iceberg that’s almost 1,500 square miles (4,000 sq km), it won’t disappear overnight. About the iceberg’s progress, NASA said:

The berg became unstuck from the seafloor in the early 2020s … Past icebergs in this area eventually … entered the Drake Passage, a turbulent body of water between South America’s Cape Horn and Antarctica’s South Shetland Islands. From there, they typically move north toward the South Atlantic and quickly melt in the region’s warmer waters.

Title holder for now

A23a hasn’t always been the title holder for world’s largest iceberg. One of the other icebergs to be crowned “world’s largest” was A-76. In 2021, this large iceberg calved from Antarctica’s Ronne Ice Shelf before breaking up. And before A-76, iceberg A-68 briefly took the title in 2017 before fracturing.

Watch the animation of iceberg A23a below as it moves over the course of a month below cloudy Antarctic skies.

Say hello to iceberg A23a, the largest iceberg in the world.

This extraordinary month-long time lapse captures its journey from the Weddell Sea into open ocean waters. pic.twitter.com/TEttjhxp4R

— CIRA (@CIRA_CSU) December 5, 2023

Bottom line: Weather satellites such as NOAA-21 are tracking the movements of the world’s largest iceberg, A23a, which is headed toward the South Atlantic.

The post World’s largest iceberg headed toward warm waters first appeared on EarthSky.

Betelgeuse nearly disappeared

The bright star Betelgeuse did become fainter – and, for experienced observers using the right equipment, nearly disappeared – last night (December 11, 2023). The event occurred as asteroid Leona passed in front of the star. But the event was quick! And it was subtle: a momentary dimming of the star.

El asteroide 319 Leona pasó esta noche frente a la estrella Betelgeuse y parece ser que solo disminuyó su brillantez un par de segundos y no la ocultó totalmente, al menos desde la perspectiva de Italia. "Spikes" o líneas de brillo desaparecen brevemente.

(Video: Antonio Piras) pic.twitter.com/NVV7n5q8gv

— SocAstronomíaCaribe (@Soc_AstroCaribe) December 12, 2023

Translation: Asteroid 319 Leona passed in front of the star Betelgeuse tonight and it seems that it only decreased its brightness for a couple of seconds and did not completely hide it, at least from the perspective of Italy. “Spikes” or glow lines disappear briefly. Video: Antonio Piras.

The post above – from Italy – shows what the eye would have seen: a dimming, but not a total disappearance.

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Report from cyberspace

We also heard from experienced observer and EarthSky community member Eliot Herman in Tucson, Arizona, who said he watched the event online at several different channels. He said:

I watched first in Sardina. It looked maybe 50% decrease for 2 seconds there. Then I flipped to Portugal and saw nothing. Betelguese must either be larger than thought in apparent diameter or the asteroid smaller.

And here’s a light curve

Preliminary light curve of a recording of the stellar occultation of #Betelgeuse by asteroid (319) Leona by M. O'Connell and A. Pratt, located south of Alicante, Spain. Camera Watec 910 HX/RC and 40mm f/4.5 apo with Bessel V filter.? pic.twitter.com/iEeFXSTwOm

— IOTA / European Section (@IOTAEuropeanSec) December 12, 2023

From Córdoba, Andalusia

The video above is from Sebastian Voltmer (@SeVoSpace on Twitter, @spacemovie on YouTube). He was observing at Almodóvar del Río, a Spanish municipality in the province of Córdoba, Andalusia.

Betelgeuse eclipse on December 11 or 12

Betelgeuse is a famous red supergiant star in the constellation Orion the Hunter. Prior to the event, Betelgeuse’s light was predicted to look dimmed or extinguished for up to 7 seconds. But we didn’t see any reports of its dimming for that long (some might still come in).

The event took place at 1:24:54 UTC on December 12, 2023.

Betelgeuse is a temperamental star

Betelgeuse is already famous for how it varies in brightness. And, since 2019, there’s been a noticeable uptick in the brightening and dimming of Betelgeuse. It’s the nearest red supergiant star to Earth, lying some 1,000 light-years away. It will explode someday, though that might be today or thousands of years from now. A paper in 2023 said that it might explode within “tens of years.” That would be amazing to see!

If it were to explode, we would see it as an incredibly bright star, even visible in daylight for roughly a year until it faded away completely, leaving a darkness where Orion’s shoulder was. Fortunately, Earth is too far away for this explosion to harm, much less destroy, life on Earth.

Bottom line: On December 11 and 12, 2023, the star Betelgeuse dimmed, and nearly disappeared, for several seconds as asteroid Leona passed in front of it.

The post Betelgeuse nearly disappeared – for some – in rare eclipse first appeared on EarthSky.

Best northern lights photos of 2023

The peak of the sun’s 11-year cycle could come as early as 2024. And – if you’ve been following EarthSky’s daily sun news post – you know that auroras (both northern and southern lights) have been brightening high-latitude skies. From his travel photography blog Capture the Atlas, Dan Zafra shared with EarthSky his picks for the 25 best aurora images of 2023 from photographers around the world. The submissions here are from eight countries, including Australia and New Zealand. You can see the full set of 25 images at Zafra’s website.

Do you have a great image of the aurora to share? You can submit it to us at EarthSky Community Photos.

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Gatklettur Northern Lights by Stefano Pellegrini

Lost Who I Want To Be by Jordan McInally

Beauty of the North by Elena Ermolina

March Michigan Nights by Justin Miller

The dance of the green lady by Luis Cajete

The Red Flame by Laura Oppelt

Bakers Oven Aurora Australis by Josh Beames

Waning Sun by Alex Wides

Lady in Pink by Kenneth LeRose

Bottom line: The blog Capture the Atlas announced its 2023 Northern Lights Photographer of the Year contest. This annual edition showcases 25 of the best aurora photos taken from all over the world. See some of the best northern lights photos in the world here.

Via Capture the Atlas

The post See the best northern lights photos of 2023 first appeared on EarthSky.

Check out these Comet Nishimura photos from around the world.

Nishimura and the Sigma-Hydrid meteors

Comet C/2023 P1 (Nishimura) burst into our consciousness in August of 2023. It never got as bright as some hoped, but it still made a glorious target for astrophotographers. But is there still a chance to see parts of Comet Nishimura? Yes, only not as the comet itself, but instead as the dust it left behind in our atmosphere. Astronomers think Nishimura may be the parent comet of an annual meteor shower known as the Sigma-Hydrids. This minor annual shower is active each year between December 9 and 12. Scientists will be closely monitoring the shower this year to see if there’s an uptick in meteors. And it might be worth it for us to go out and look, too!

So, if Nishimura is indeed related to the Sigma-Hydrids, then the comet might have “refilled” its path with icy comet particles. While this is normally a very quiet shower, it might be more active this year.

The video below is from December 2022, taken in the Caribbean. It’s a Sigma-Hydrid meteor, a possible Nishimura-related meteor!

Videos of Nishimura

Professional observatories that peer at the sun have caught the comet in their images. You’ll find some amazing videos of the comet below.

Comet Nishimura – that great icy ball moving through space, which so many have captured on film – was closest to Earth on September 12. It was then closest to the sun (perihelion) on September 17.

Meanwhile, the comet is also expected to reappear in our dawn skies toward the end of 2023. But by then it’ll be too distant, and too dim, to view, as it sweeps farther away. But we may get to see some of what it left behind in December, however, with the Sigma-Hydrids meteor shower!

Wondering what happened to comet Nishimura? It's still quite happily sunbathing in the field of view of our @USNRL HI-1 camera on @NASA STEREO-A! Lots of great ion tail / solar wind interaction happening! ????

Download the full-res movie here: https://t.co/gkv2HCpIUS pic.twitter.com/xzHvdgBfjt

— Karl Battams (@SungrazerComets) September 26, 2023

The story of comet Nishimura

Hideo Nishimura of Kakegawa, Japan, was photographing the night sky on August 11 and 12, 2023, when he captured a new comet that now bears his name: comet C/2023 P1 (Nishimura). In fact, the comet was hiding in the sun’s glare before Nishimura picked it up in his images.

It continued to brighten as it closed in on the sun (perihelion was September 17). Later, after passing closest to Earth on September 12, it emerged low in the evening sky. Some saw it with binoculars in the western evening twilight.

A local comet

On September 1, 2023, NASA/ JPL made new orbital calculations that indicated that comet Nishimura orbits the sun every 435 years, which suggests this is a “local comet” from our solar system and not an interstellar comet.

Closest approach to Earth occurred on September 12, 2023, when the comet passed 78 million miles (125 million km) from Earth.

Perihelion – or closest approach to the sun – was on September 17, 2023, at 27 million miles (43 million km) from our star.

In fact, during perihelion, comet Nishimura passed closer to the sun than Mercury’s orbit.

Sightings of comet Nishimura

Comet Nishimura (C/2023 P1) on Sept 5, 2023. For this single shot I used my A7s and a 135mm lens.

Nishimura is a new comet that was discovered on August 11, 2023. It's expected to brighten to a magnitude of 1.8. Its closest approach to us will be on Sep 12 and its perihelion on… pic.twitter.com/BXhDo0IOpq

— Dr. Sebastian Voltmer (@SeVoSpace) September 6, 2023

comet C/2023 P1 (Nishimura) from Belfast, N Ireland at around 5am on 4th Sept 2023. Cropped from a 100mm image – stack of 50 x 3secs at ISO800. (Some problems with stacking caused a halo above neighbour's roof!) @martinastro2005 pic.twitter.com/jCuuZa3egN

— Philip?EcotrakNI (@EcotrakNI) September 4, 2023

comet C/2023 P1 (Nishimura): Such a strong solar wind. The disconnection event on September 2nd – the spectacular development in a 20-minute animation (RASA 11 QHY600) and 4x80sec red Michael Jäger pic.twitter.com/qf43YqhBbl

— Michael Jäger (@Komet123Jager) September 2, 2023

Bottom line: Comet Nishimura may be the parent comet to the Signma-Hydrid meteor shower, which peaks between December 9 and 12. Will the shower be more active this year? The only way to know is to go look!

See photos of comet Nishimura from the EarthSky community

Via:

NASA

Harvard

IAU Minor Planet Center

Star Walk

The post Comet Nishimura and the Sigma-Hydrid meteors first appeared on EarthSky.

Oldest known wild bird spotted in the Pacific

An albatross named Wisdom, the oldest known wild bird at 70 years old, at least, has once again returned to the Midway Atoll National Wildlife Refuge in the Pacific. A volunteer spotted the septuagenarian at the refuge on Friday, December 1, 2023. And she looks good for her age!

The U.S. Geological Survey (USGS) first tagged Wisdom at Midway, in the 1950s. The tag bears the designation Z333. Experts estimate that she was hatched at least as early at 1951, if not earlier. That would put her at a minimum of 72 years old.

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Laysan albatrosses

Wisdom is a Laysan albatross, or moli. These birds return to tiny atolls in the Pacific every year starting in October. Because of their long lifespans, they can be a challenge to study. A typical albatross lives for two to three times the length of a biologist’s career.

Plus, albatrosses are difficult to study because they spend up to 90% of their lives in the air, moving from their summer feeding ground in the northern Pacific, to the tiny atolls in the mid-Pacific that are their places to nest.

Albatrosses are ‘near-threatened’

The population of the Laysan albatross falls in the category of “near-threatened.” They’re no longer hunted as they were in the early 1900s. But their numbers haven’t yet recovered.

In 2009, scientists estimated that around 10,000 albatrosses died annually due to poisoning at Midway. Chicks born in nests close to buildings left behind by the Navy ingested lead-based paint chips that led to their deaths.

By August 2018, the U.S. had remediated the lead problem and declared Midway Atoll lead-free.

The U.S. Fish and Wildlife Service has said:

Wisdom’s continued contribution to the fragile albatross population is remarkable and important. Her health and dedication have led to the birth of other healthy offspring, which will help recover albatross populations on Laysan and other islands.

Bottom line: A beloved albatross named Wisdom is the world’s oldest known wild bird. She’s more than 70! And she just returned again to her winter nesting ground.

Read more: New chick for oldest known wild bird Wisdom

The post Oldest known wild bird, Wisdom, is back! first appeared on EarthSky.

Comet Halley farthest from the sun on Saturday

Comet Halley – the most famous of all comets – is coming to the end of the invisible tether binding it to our sun. This comet has been heading away from the sun since its last closest approach in 1986. Now it’s reaching the end of its outward journey, due to arrive at its farthest point from our sun on December 9, 2023. Afterwards, it’ll start making the trip back toward the sun, due to arrive in our vicinity by 2061.

Why is Comet Halley so famous? It was the first comet ever predicted to return. After observing a “hairy star” in 1682, English astronomer Edmond Halley looked at the historic record of such objects. He noted similarities in visits from objects in 1531, 1607 and 1682 and believed they were appearances of the same object. Then, he predicted that this “hairy star” would return in 1758.

And so it did, although Halley himself didn’t live to see it. But the comet now bears his name. Perhaps some of you have seen Comet Halley. The comet’s most recent close approach to the sun – called perihelion – was on February 9, 1986. Its next closest approach to the sun will be on July 28, 2061.

And that means means Comet Halley is now nearing its farthest from the sun – or aphelion – on December 9, 2023.

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Halley’s orbit

The relatively predictable and short orbit is what made Comet Halley famous. But – as with all things in nature – the orbit of Comet Halley isn’t precisely predictable. It varies slightly from 75 to 79 years. Still, it has a short-enough orbital period that it’s possible for someone to see it twice in their lifetime. Edmond Halley’s prediction of its return made this idea testable. It became a key to understanding what comets were.

Comet Halley is what we now call a short-period comet, or one that takes less than 200 years to orbit the sun. Long-period comets can take from 200 years up to millions of years to orbit the sun. In fact, it can take comets in the Oort Cloud as long as 30 million years to orbit the sun once.

The comet and 2 meteor showers

Clearly, aphelion – marking an object’s farthest point from the sun – isn’t a good time to observe Comet Halley. But if you don’t want to wait another 38 years to see at least bits of Comet Halley, I’ve got good news for you. We get to see parts of this comet every year in the form of meteors.

Comet Halley is the parent of two meteor showers. When comets orbit the sun, they leave bits of cometary dust behind. And for this comet, Earth’s orbit intersects two of these paths in one calendar year. The first is in May with the Eta Aquariid meteor shower. Then, in October, we intersect with another part of Halley’s path when we see the Orionid meteors.

Bottom line: Comet Halley reaches its farthest point in its orbit from the sun – called aphelion – on December 9, 2023. Afterwards, it’ll begin its return trip to the inner solar system, reaching its closest point to the sun on July 28, 2061.

The post Comet Halley to reach farthest point from sun on December 9 first appeared on EarthSky.