Feed aggregator

A black hole 33 times the mass of the sun is the largest stellar black hole ever spotted, and its strange companion star could help explain how it got so huge

After being packed up in Germany, a long voyage to the US and then a month in storage, ESA’s EarthCARE satellite has been carefully lifted out of its transport container so that the team at the launch site can start getting it ready for its big day in May.

Wading through the wealth of data from ESA’s Gaia mission, scientists have uncovered a ‘sleeping giant’. A large black hole, with a mass of nearly 33 times the mass of the Sun, was hiding in the constellation Aquila, less than 2000 light-years from Earth. This is the first time a black hole of stellar origin this big has been spotted within the Milky Way. So far, black holes of this type have only been observed in very distant galaxies. The discovery challenges our understanding of how massive stars develop and evolve. 

It’s been just over a week since millions of people flocked to places across North America for a glimpse of moonshadow. The total solar eclipse of April 8th, 2024 was a spectacular sight for many on the ground. From space, however, it was even more impressive as Earth-observing satellites such as GOES-16 captured the sight of the shadow sweeping over Earth.

NASA even got a snap of the eclipse from the Moon, as taken by the Lunar Reconnaissance Orbiter Camera (LROC). Unlike most Earth-based photographers, however, LROC’s view was a tricky one to get. The cameras are line scanners and their images get built up line-by-line. That process requires the spacecraft to slew to keep up with the action and build up a complete view. Amazingly, it took only 20 seconds to capture all the action.

A short video of the eclipse shadow along the path of totality, captured by NASA’s Deep Space Climate Observatory.

NASA’s Deep Space Climate Observatory got an amazing view from Earth orbit, capturing the entire eclipse as it passed over the continent. That observatory “lives” out at LaGrange Point 1, which enabled it to get a full view of Earth and the Moon’s shadow.

Eclipse as Experience

For most viewers, the chase to see an eclipse meant driving (or flying) to somewhere along the path of totality to get the best view. That path stretched from the Pacific Ocean off the coast of Mexico up toward the northern Canadian provinces. That meant a wide swath of the U.S. experienced totality. Or course, the weather had to be good to see it all. In most places, that actually turned out reasonably well. Social media immediately came alive with images of the eclipse, people enjoying it, and others waiting vainly for a break in the clouds.

A composite of images taken during the total solar eclipse showing all the phases leading up to and after totality. NASA/Keegan Barber.

This writer was stationed off the coast of Mazatlán, Mexico, on a cruise ship with a group of amateur and professional astronomers. Although there were a few clouds, the view of the eclipsed Sun was nearly pristine. From the ship, everyone was able to watch the shadow approach, feel the temperature drop, and marvel at 4 minutes and 20 seconds of totality.

A projection of the partially eclipsed Sun on the stack of a cruise ship off the coast of Mazatlan. Image credit: Carolyn Collins Petersen.

In a few regions, however, people were only able to watch clouds get dark. And, for the majority of viewers outside of the path of totality, they could only get a partial view. Still, in many places, people went out to experience the event using eclipse glasses or pinhole projection methods to see those partial phases.

Eclipse from the Air

For those who could “fly the eclipse” it was an opportunity to take a jet plane along the path and prolong the experience. During the eclipse, flight-tracking apps showed a huge increase in traffic along the path. Several airlines had flights that tracked the path, giving lucky passengers the view of a lifetime for a short period.

A pilot flying a WB-57 jet during the total solar eclipse on April 8, 2024. Credit: NASA/Mallory Yates

At least one NASA jet pilot captured a view as the aircraft passed through the shadow. In space, the astronauts aboard the International Space Station got a great shot of the umbra and penumbra passing over the maritime provinces of Canada.

A view of the eclipse shadow from the International Space Station. Courtesy NASA. Future Eclipses

The 2024 eclipse across North America left many with a taste for more moonshadow experience. Unfortunately, that was the last one for this part of the world until 2045. That’s when another one will sweep across the continent. Before that, however, there are other total solar eclipses, as well as lunar and annular events. The years 2026, 2027, and 2028 will feature totalities across parts of Europe, Egypt, and Australia. You can find out locations and dates for others at Mr. Eclipse, as well as NASA’s own eclipse site. For each event, there’ll be plenty of information about safe viewing, as well as “broadcasts” on social media for those outside of the paths of totality.

For More Information

2024 Eclipse as Seen From The Moon
The April 8 Total Solar Eclipse: Through the Eyes of NASA

The post More Views of the 2024 Eclipse, from the Moon and Earth Orbit appeared first on Universe Today.

Captured in this snapshot, the shadow of the Moon came to Lake Magog,

I’m really not sure what to call it but a ‘dusty sneeze’ is probably as good as anything. We have known for some years that stars surround themselves with a disk of gas and dust known as the protostellar disk. The star interacts with it, occasionally discharging gas and dust regularly. Studying the magnetic fields revealed that they are weaker than expected. A new proposal suggests that the discharge mechanism ‘sneezes’ some of the magnetic flux out into space. Using ALMA, the team are hoping to understand the discharges and how they influence stellar formation. 

In a fairly inconspicuous part of the Galaxy, a star slowly formed out of a cloud of gas and dust. This event took place around 4.6 billion years ago and soon, the hot young star began to clear the surrounding area of gas and dust. What remained was a disk surrounding the star known as a protostellar disk. Eventually the planets of our Solar System formed. It is not unique to our own system though as there have been disks like this found around many stars. A very well known example are the stars in the Trapezium cluster inside the Orion Nebula. 

Behind the Gas and Dust of Orion’s Trapezium Cluster

A team in Japan, from the Kyushu University have been examining data from the ALMA radio telescope to learn more about stars in the earliest stages of development. To their surprise they discovered the disks around new stars seem to emit jets or plumes of dust and gas and even electromagnetic energy. The team dubbed them ‘sneezes’ and its this process that seems to slowly erode the magnetic flux of a young star system. 

ALMA’s high-resolution images of nearby protoplanetary disks, which are results of the Disk Substructures at High Angular Resolution Project (DSHARP). The observatory is often used to look for planet birth clouds like these and the one around HD 169142. Credit: ALMA (ESO/NAOJ/NRAO), S. Andrews et al.; NRAO/AUI/NSF, S. Dagnello

One phenomenon of the disks is a powerful magnetic field which permeates through the region. It therefore carries a magnetic flux and herein lies the problem. The magnetic fields would be far stronger than those observed if the magnetic flux had been retained from day one. History shows us, they didn’t seem to retain them so the flux has been slowly eroded away in new star and planetary systems. 

One such proposal was that the field slowly decreased as the surrounding dust cloud collapsed into the core of the star. To explore the phenomenon the team studied MC 27, a system 450 light years away using ALMA, the Atacama Large Millimetre Array. In total, 66 radio telescopes pointed to the object from an altitude of 5,000 metres. They found that there were ‘spike like’ structures that seemed to extend out by a few astronomical units (average distance between Sun and Earth.)

The Atacama Large Millimeter/submillimeter Array (ALMA). Credit: C. Padilla, NRAO/AUI/NSF

The team found that the features contained gas and dust but had a magnetic flux. Known as ‘interchange instability’, the field exhibits instabilities when it reacts with different densities of gas. They referred to these, not as interchange instability but as a baby star’s sneeze. Just like a human sneeze which expels dust and gas or rather air from our bodies, so a young hot star ‘sneezing’ releases gas and dust from the disk. 

Further exploration revealed signs of other plumes several thousands of astronomical units from the protostellar disk. They suggest that these are evidence of other sneezes in the past. It’s not just on MC 27 though, the spikes have been seen in other star systems but more time is needed to be able to fully understand the implications of the discovery. 

Source : Twinkle twinkle baby star, ‘sneezes’ tell us how you are

The post Baby Stars Discharge “Sneezes” of Gas and Dust appeared first on Universe Today.

The total solar eclipse of 2024 was an epic experience to share with my daughter. It was one part celestial event, one part college prep.

A detailed analysis of the Winchcombe meteorite has found evidence that its parent asteroid was altered by water before being smashed apart multiple times.

The most recognizable feature on Pluto is its “heart,” a relatively bright valentine-shaped area known as Tombaugh Regio. How that heart got started is one of the dwarf planet’s deepest mysteries — but now researchers say they’ve come up with the most likely scenario, involving a primordial collision with a planetary body that was a little more than 400 miles wide.

The scientific term for what happened, according to a study published today in Nature Astronomy, is “splat.”

Astronomers from the University of Bern in Switzerland and the University of Arizona looked for computer simulations that produced dynamical results similar to what’s seen in data from NASA’s New Horizons probe. They found a set of simulations that made for a close match, but also ran counter to previous suggestions that Pluto harbors a deep subsurface ocean. They said their scenario doesn’t depend on the existence of a deep ocean — which could lead scientists to rewrite the history of Pluto’s geological evolution.

An artist’s conception shows the presumed collision of a planetary body with Pluto. (Thibaut Roger/University of Bern)

University of Arizona astronomer Adeene Denton, one of the study’s co-authors, said the formation of the heart “provides a critical window into the earliest periods of Pluto’s history.”

“By expanding our investigation to include more unusual formation scenarios, we’ve learned some totally new possibilities for Pluto’s evolution,” Denton said in a news release. Similar scenarios could apply to other objects in the Kuiper Belt, the ring of icy worlds on the edge of our solar system.

The study focuses on the western half of the heart, a roughly 1,000-mile-wide, teardrop-shaped region called Sputnik Planitia. That region contains an assortment of ices and is roughly 2.5 miles lower in elevation than the rest of Pluto. It’s clearly the result of a massive impact.

“While the vast majority of Pluto’s surface consists of methane ice and its derivatives, covering a water-ice crust, the Planitia is predominantly filled with nitrogen ice which most likely accumulated quickly after the impact due to the lower altitude,” said study lead author Harry Ballantyne, a research associate at the University of Bern.

The eastern half of the heart is covered by a similar but much thinner layer of nitrogen ice. The origins of that part of Tombaugh Regio are still unclear, but it’s probably related to the processes that shaped Sputnik Planitia.

Ballantyne and his colleagues ran a wide assortment of computer simulations for the ancient impact. Those simulations reflected a range of sizes and compositions for the impacting body, at different velocities and angles of approach. The best fit for Sputnik Planitia’s shape involved a 400-mile-wide object, composed of 15% rock, coming in at an angle of 30 degrees and hitting Pluto at a relatively low velocity.

Based on those parameters, the object would have plowed through Pluto’s surface with a splat. The resulting shape wouldn’t look like your typical impact crater. Instead, it would look like a bright, icy teardrop, with the rocky core of the impacting body ending up at the tail of the teardrop.

“Pluto’s core is so cold that the rocks remained very hard and did not melt despite the heat of the impact, and thanks to the angle of impact and the low velocity, the core of the impactor did not sink into Pluto’s core, but remained intact as a splat on it,” Ballantyne explained.

Previous scenarios for Sputnik Planitia’s origin relied on the presence of a deep ocean beneath Pluto’s surface to explain why the impact region hasn’t drifted toward Pluto’s nearest pole over time. But the researchers behind the newly published study found that the best matches in their simulations called for an ocean measuring no more than 30 miles in depth. “If the influence of ammonia proves negligible, Pluto might not possess a subsurface ocean at all, in accordance with our nominal case,” they wrote.

The researchers say they’ll continue their work to model Pluto’s geological history — and how those models could apply to other Kuiper Belt objects as well.

Meanwhile, the New Horizons spacecraft is continuing its journey through the solar system’s far reaches, nearly nine years after its Pluto flyby. Mission scientists recently reported detecting higher than expected levels of interplanetary dust, which suggests there may be more to the Kuiper Belt than they thought. They’re hoping to identify yet another icy world that the spacecraft can observe up close in the late 2020s or the 2030s.

In addition to Ballantyne and Denton, the authors of the Nature Astronomy study, titled “Sputnik Planitia as an Impactor Remnant Indicative of an Ancient Rocky Mascon in an Oceanless Pluto,” include Erik Asphaug, Alexandre Emsenhuber and Martin Jutzi.

The post How Did Pluto Get Its Heart? Scientists Suggest an Answer appeared first on Universe Today.

Look through the names and origins of the constellations and you will soon realise that many cultures had a hand in their conceptualisation. Among them are the Egyptians who were fantastic astronomers. The movement of the sky played a vital role in ancient Egypt including the development of the 365 day year and the 24 hour day. Like many other cultures they say the Sun, Moon and planets as gods. Surprisingly though, the bright Milky Way seems not to have played a vital role. Some new research suggests that this may not be the case and it may have been a manifestation of the sky goddess Nut! 

It’s a fairly well accepted theory that the pyramids of Egypt were constructed in some way as a representation of or tribute to the sky. The Sun god Ra was often depicted sailing the Sun across the sky in a boat but the Milky Way was never seemed to be a big part, other than perhaps some consideration that the river Nile could represent it. 

Nile River, Lake Nasser and the Red Sea, Egypt

Back in the days of ancient Egypt, light pollution really wasn’t a thing. The Milky Way would have been far more prominent than for many stargazers today. A recent study by astrophysicists at the University of Portsmouth suggest that a lesser heard god by the name of Nut had something to do with it. 

Hunt through Egyptian artwork and you will often see a star-filled woman arched over another person. The woman is Nut, the goddess of the sky and the other figure represents her brother, the god of Earth, Geb. Nut has a very specific job though, she protects the Earth from being flooded from waters of the void! Presumably this would be the void of space but of course back then we didn’t have such a great understanding of the cosmos. She also swallowed the Sun as it sets, giving birth to it again in the morning. 

Thankfully the Egyptians were fabulous at recording things and so there have been plenty of Egyptian texts to refer to. Running simulations from the evidence in the documents, the team (led by Dr Or Graur Associate Professor in Astrophysics) suggest that the Milky Way represented Nut’s outstretched arms in the winter and her backbone in the summer. This suggestion aligns with the broad patterns in the Milky Way. 

The arch of the Milky Way seen over Bisei Town in Japan. It prides itself on its dark skies, but faces scattered light pollution from other nearby municipalities. Courtesy DarkSky.Org.

Dr Graur went on to explain that their results revealed that Nut had far more of a functional role too. She was involved in the transition of deceased souls to the afterlife and had a connection with annual bird migrations. This is in line with many cultures like those in North and Central America believing the Milky Way was a road used by spirits or those in Finland and the Baltics who believed it was a path for birds. 

Source : The hidden role of the Milky Way in ancient Egyptian mythology

The post The Milky Way’s Role in Ancient Egyptian Mythology appeared first on Universe Today.

The small object that crashed through the roof of a Florida home last month was indeed part of a pallet jettisoned from the ISS three years ago, NASA has confirmed.

19 min read

The next full Moon is the Pink Moon, Sprouting Grass Moon, Egg Moon, Fish Moon, the Pesach or Passover Moon

The next full Moon is the Pink Moon, Sprouting Grass Moon, Egg Moon, Fish Moon, the Pesach or Passover Moon, the Hanuman Jayanti Festival Moon, and Bak Poya. 

The next full Moon will be Tuesday evening, April 23, 2024, appearing opposite the Sun (in Earth-based longitude) at 7:49 PM EDT. This will be on Wednesday from the time zones of the UK, Ireland, and Portugal eastward across Europe, Africa, Asia, and Australia to the International Date Line in the mid-Pacific. The Moon will appear full for about 3 days around this time, from Monday morning to Thursday morning. 

The phases of the Moon for April 2024 NASA/JPL-Caltech

The Maine Farmers’ Almanac began publishing “Indian” names for full Moons in the 1930s and these names are now widely known and used. According to this almanac, as the full Moon in April the tribes of the northeastern United States called this the Pink Moon, named after the herb moss pink, also known as creeping phlox, moss phlox, or mountain phlox, a plant native to the eastern USA that is one of the earliest widespread flowers of spring. Other names for this Moon include the Sprouting Grass Moon, the Egg Moon, and among coastal tribes the Fish Moon, as this was when the shad swam upstream to spawn.

This is the Pesach or Passover Moon. In the Hebrew calendar this full Moon is in the middle of Nisan, with Pesach or Passover beginning on the 15th day of Nisan. Pesach or Passover begins at sundown on Monday, April 22, and ends at nightfall on April 30, 2024. The Seder feasts are on the first two evenings of Passover. 

There are a number of variations of the Hindu lunisolar calendar, but for most regions this full Moon corresponds with the Hanuman Jayanti festival, the celebration of the birth of Lord Hanuman. 

For Buddhists, especially in Sri Lanka, this full Moon is Bak Poya, commemorating when the Buddha visited Sri Lanka and settled a dispute between chiefs, avoiding a war. 

This full Moon is near the middle of Shawwāl, the tenth month of the Islamic calendar and the middle of the third month of the Chinese year of the Dragon.

As usual, the wearing of suitably celebratory celestial attire is encouraged in honor of the full Moon. Enjoy the early flowers and sprouting grass of spring, leave an extra seat at the table, and avoid starting any wars!

As for other celestial events between now and the full Moon after next (with specific times and angles based on the location of NASA Headquarters in Washington, DC):

As spring continues the daily periods of sunlight continue to lengthen, having changed at their fastest around the equinox on March 19, 2024. On Tuesday, April 23 (the day of the full Moon), morning twilight will begin at 5:18 AM EDT, sunrise will be at 6:20 AM, solar noon will be at 1:06 PM when the Sun will reach its maximum altitude of 64.0 degrees, sunset will be at 7:53 PM, and evening twilight will end at 8:56 PM. By Thursday, May 23 (the day of the full Moon after next), morning twilight will begin at 4:40 AM, sunrise will be at 5:49 AM, solar noon will be at 1:05 PM when the Sun will reach its maximum altitude of 71.9 degrees, sunset will be at 8:21 PM, and evening twilight will end at 9:30 PM. 

Meteor Showers

This year, the Aquariids (031 ETA) meteor shower is predicted to peak the afternoon of May 5, 2024 (when we can’t see them from the Washington, DC area). If you are in the tropics or the southern hemisphere, the predicted peak rate (under the best possible conditions) is about 50 visible meteors per hour (called zenithal hourly rate or ZHR). However, this meteor shower has a broad peak. As reported by the International Meteor Organization, data since 1984 show that ZHRs are generally above 30 from May 3 to May 10 and modeling suggests there may be enhanced activity near the peak sometime between May 4 and May 6. 

Viewing conditions from the Washington, DC area will be far from ideal, as DC is on the northern edge of visibility. With the ZHR relatively low (compared to the three big meteor showers of the year) and the radiant low on the horizon, viewing these meteors from our light-polluted urban areas will be difficult. But if you find yourself out in the early morning between May 3 and May 10 in an area with clear, dark skies and a clear view towards the east-southeastern horizon, you may see some meteors! These meteors are caused by debris from Halley’s Comet entering our atmosphere at 66 kilometers per second (148,000 miles per hour). 

For the DC area the time to look closest to the peak should be the early morning of Monday, May 6. The radiant (the point that the meteors will appear to radiate out from) will rise on the eastern horizon (around 2:35 AM EDT) about 2.5 hours before morning twilight beings. At radiant rise, half of the meteors are hidden by the horizon, so the higher the radiant, the better the viewing. The radiant will be about 27 degrees above the east-southeastern horizon by the time morning twilight begins (at 4:59 AM), so the hour or so before this should be the best time to look.

If you go looking for these meteors, be sure to give your eyes plenty of time to adapt to the dark. The rod cells in your eyes are more sensitive to low light levels but play little role in color vision. Your color-sensing cone cells are concentrated near the center of your view with more of the rod cells on the edge of your view. Since some meteors are faint, you will tend to see more meteors from the “corner of your eye” (which is why you need to view a large part of the sky). Your color vision (cone cells) will adapt to darkness in about 10 minutes, but your more sensitive night vision rod cells will continue to improve for an hour or more (with most of the improvement in the first 35 to 45 minutes). The more sensitive your eyes are, the more chance you will have of seeing meteors. Even a short exposure to light (from passing car headlights, etc.) will start the adaptation over again (so no turning on a light or your cell phone to check what time it is). 

Evening Sky Highlights

On the evening of Tuesday, April 23, 2024 (the evening of the day of the full Moon), as twilight ends (at 8:56 PM EDT), the rising Moon will be 10 degrees above the east-southeastern horizon. The bright planet Jupiter will be 4 degrees above the west-northwestern horizon. The bright object appearing closest to overhead will be Regulus at 63 degrees above the southern horizon. Regulus is the 21st brightest star in our night sky and the brightest star in the constellation Leo the lion. The Arabic name for Regulus translates as “the heart of the lion.” Although we see Regulus as a single star, it is actually four stars (two pairs of stars orbiting each other). Regulus is about 79 light-years from us. 

As this lunar cycle progresses, Jupiter and the background of stars will appear to shift westward each evening (as the Earth moves around the Sun). April 29 will be the last evening Jupiter will be above the west-northwestern horizon as evening twilight ends. The waxing Moon will pass by Pollux on May 12, Regulus on May 15, and Spica on May 19. 

By the evening of Thursday, May 23 (the evening of the day of the full Moon after next), as twilight ends (at 9:30 PM EDT), the rising Moon will be 4 degrees above the southeastern horizon with the bright star Antares just off the edge of the Moon. For parts of South and Central America, as well as the Caribbean and parts of the eastern USA (including DC) the Moon will be passing in front of Antares, blocking it from view. The bright object appearing closest to overhead will be Arcturus at 60 degrees above the east-southeastern horizon. Arcturus is the brightest star in the constellation Boötes the herdsman or plowman and the 4th brightest star in our night sky. It is 36.7 light years from us. While it has about the same mass as our Sun, it is about 2.6 billion years older and has used up its core hydrogen, becoming a red giant 25 times the size and 170 times the brightness of our Sun. 

Morning Sky Highlights

On the morning of Tuesday, April 23, 2024 (the morning of the day of the full Moon), as twilight begins (at 5:18 AM EDT), the setting full Moon will be 7 degrees above the west-southwestern horizon with the bright star Spica 2.5 degrees to the lower left of the Moon. The planet Mars will be 5 degrees above the eastern horizon and the planet Saturn will be 7 degrees above the east-southeastern horizon. The planet Mercury will rise 22 minutes after morning twilight begins and will be faint, making it difficult to see in the glow of dawn. The bright object appearing closest to overhead will be the star Vega at 86 degrees above the eastern horizon. Vega is the brightest star in the constellation Lyra the lyre and is one of the three bright stars in the “Summer Triangle” along with Deneb and Altair. Vega is the 5th brightest star in our night sky, about 25 light-years from Earth, twice the mass of our Sun, and shines 40 times brighter than our Sun. 

As this lunar cycle progresses, Saturn and the background of stars will appear to shift westward each evening, while Mars will hover low on the eastern horizon, drifting slightly to the left. Mercury will brighten and shift higher in the eastern sky, making it easier to see in the glow of dawn, but will not rise until after morning twilight begins. Mercury will reach its greatest angular separation from the Sun on May 9. The waning Moon will pass by Antares on April 26 and 27, Saturn on May 4, Mars on May 5, and Mercury on May 6. Although viewing conditions will not be good from the DC area (and latitudes farther north), the η-Aquariids meteor shower will be near its peak from May 3 to May 10, with our peak viewing expected the hour or so before morning twilight begins on May 6. 

By the morning of Thursday, May 23 (the morning of the day of the full Moon after next), as twilight begins (at 4:40 AM EDT), the setting full Moon will be 7 degrees above the southwestern horizon. The planet Mars will be 10 degrees above the eastern horizon and the planet Saturn will be 22 degrees above the east-southeastern horizon. Mercury will rise on the east-northeastern horizon 14 minutes after morning twilight begins. The bright object appearing closest to overhead will still be the star Vega at 78 degrees above the western horizon, with Deneb a close second at 76.5 degrees above the northeastern horizon. 

Detailed Daily Guide

Here for your reference is a day-by-day listing of celestial events between now and the full Moon after next. The times and angles are based on the location of NASA Headquarters in Washington, DC, and some of these details may differ for where you are (I use parentheses to indicate times specific to the DC area). 

Wednesday evening into Thursday morning, April 17 to 18, 2024, the bright star Regulus will be to the lower left of the waxing gibbous Moon. As twilight ends (at 8:49 PM EDT) Regulus will be 7.5 degrees from the Moon. When Regulus sets on the west-northwestern horizon (at 4:12 AM) it will be 4.5 degrees from the Moon. 

Thursday evening into Friday morning, April 18 to 19, 2024, the waxing gibbous Moon will have shifted to the other side of the bright star Regulus. As twilight ends (at 8:50 PM EDT) Regulus will be 6 degrees to the upper right of the Moon. About 1 hour later (at 9:53 PM) the Moon will reach its highest for the night with Regulus 6 degrees to the right. Regulus will rotate clockwise and away from the Moon as the night progresses, reaching about 8 degrees to the lower right around 3 AM. 

Friday night, April 19, 2024, at 10:09 PM EDT, the waxing gibbous Moon will be at apogee, its farthest from the Earth for this orbit. 

Friday morning, April 19, 2024, will be the first morning that the planet Mercury will rise on the eastern horizon more than 30 minutes before sunrise, a very rough estimate of the earliest it might start being visible in the glow of dawn. Mercury will be quite faint, but will brighten each morning as it shows a larger illuminated crescent towards the Earth. However, this will not be a favorable apparition for Mercury viewing, as even at its highest it will not rise before twilight begins. 

Sunday, April 21, 2024 will be when the comet 12P/Pons-Brooks will be at its closest to the Sun. The week or two before this might be a good time to look for this comet with binoculars. If the trail of gas and dust the comet is giving off doesn’t change significantly (a very big and uncertain “if”) then the brightness of the comet should increase to a maximum on April 21. However, interference from the light of the waxing Moon will also increase beginning April 9, and the comet will shift closer to the horizon each evening. As twilight ends on April 21 (at 8:53 PM EDT) the Moon will be 96% illuminated and the comet will be only 2.7 degrees above the horizon. April 24 will be the last evening the comet will be above the horizon before evening twilight ends (at 8:57 PM). 

Monday, April 22, 2024, is International Mother Earth Day. See https://www.un.org/en/observances/earth-day for more information. 

Monday evening into Tuesday morning, April 22 to 23, 2024, the bright star Spica will be to the lower right of the full Moon. Spica will be a little more than 1 degree from the Moon as twilight ends and will shift closer until little before midnight, after which they will separate again. Spica will be 1 degree from the Moon as the Moon reaches its highest for the night (at 12:31 AM EDT) and will be 2.5 degrees from the Moon as twilight begins (at 5:18 AM). 

As mentioned above, the full Moon will be Tuesday evening, April 23, 2024, at 7:49 PM EDT. This will be on Wednesday from the time zones of the UK, Ireland, and Portugal eastward across Europe, Africa, Asia, and Australia to the International Date Line. The Moon will appear full for about 3 days centered on this time, from Monday morning to Thursday morning.

Friday morning, April 26, 2024, the bright star Antares will be near the waning gibbous Moon. Antares will be about 8 degrees to the lower left around midnight, about 7 degrees to the left around the time the Moon reaches its highest for the night (at 2:48 AM EDT), and about 6 degrees to the upper left as morning twilight begins (at 5:13 AM). For parts of the Arabian Peninsula, the Horn of Africa, and the Indian Ocean, the Moon will actually block Antares from view. See http://www.lunar-occultations.com/iota/bstar/0426zc2366.htm for a map and information on the areas that can see this occultation. 

By late Friday night into Saturday morning, April 26 to 27, 2024, the waning gibbous Moon will have moved to the other side of the bright star Antares. As the Moon rises (at 11:09 PM EDT) Antares will be 4 degrees to the upper right, and will shift clockwise and away from the Moon as the night progresses, appearing 6 degrees to the upper right when the Moon is at its highest (at 3:42 AM) and 7 degrees to the lower right as morning twilight begins (at 5:12 AM). 

Monday evening, April 29, 2024, will be the last evening that the planet Jupiter will be above the west-northwestern horizon as evening twilight ends (at 9:03 PM EDT). 

Wednesday morning, May 1, 2024, the waning Moon will appear half-full as it reaches its last quarter at 7:27 AM EDT (when the Moon will be visible in our daylight sky).

Saturday morning, May 4, 2024, the planet Saturn will be 6 degrees to the upper right of the waning crescent Moon with the planet Mars 9 degrees to the lower left of the Moon. On the eastern horizon, Saturn will rise first (at 3:51 AM EDT), the Moon next 17 minutes later (at 4:09 AM), and Mars last 18 minutes after that (at 4:27 AM). The Moon will be 9 degrees above the east-southeastern horizon as morning twilight begins (at 5:02 AM). Later in the day (when we can’t see) the Moon will shift past Mars. For part of the Indian Ocean off of Madagascar, the Moon will actually block Mars from view. See http://www.lunar-occultations.com/iota/planets/0505mars.htm for a map and information on the areas that can see this occultation. 

Sunday morning, May 5, 2024, the waning crescent Moon will have shifted to the other side of Mars. The Moon will rise last (at 4:35 AM EDT) on the eastern horizon with Mars 4 degrees to the upper right. The Moon will be 4 degrees above the horizon as morning twilight begins (at 5 AM). 

As described in the summary above, the η-Aquariids (031 ETA) meteor shower is expected to peak when North America is on the wrong side of our planet. For dark, rural areas near Washington, DC, the time to look closest to the peak should be the early morning of Monday, May 6, 2024. The radiant (the point that the meteors will appear to radiate out from) will rise on the eastern horizon (around 2:35 AM EDT) about 2.5 hours before morning twilight begins and will reach 27 degrees above the east-southeastern horizon as morning twilight begins (at 4:59 AM). The higher the radiant, the better the viewing, so the hour or so before the start of twilight should be the best time to look. Seeing these meteors from our light-polluted urban areas (like Washington, DC) will be very difficult, but if you find yourself in an area with clear, dark skies and a clear view towards the east-southeastern horizon between May 3 and May 10 an hour or so before morning twilight begins, you may see some meteors. 

Sunday evening, May 5, 2024, at 6:11 PM EDT, the waning crescent Moon will be at perigee, its closest to the Earth for this orbit. 

Monday morning, May 6, 2024, if you have a very clear view of the east-northeastern horizon, you might be able to see in the glow of dawn the planet Mercury 3.5 degrees to the lower right of the thin, waning crescent Moon. Mercury will rise last (at 5:09 AM EDT) 10 minutes after morning twilight begins (at 4:59 AM). Mercury will likely be easier to see, as the Moon will be a very thin crescent that you may need binoculars to spot. 

Tuesday night, May 7, 2024, at 11:22 PM EDT, will be the new Moon, when the Moon passes between the Earth and the Sun and will not be visible. 

The day of or the day after the New Moon marks the start of the new month for most lunar and lunisolar calendars. The fourth month of the Chinese calendar starts on May 8, 2024. In the Islamic calendar the months traditionally start with the first sighting of the waxing crescent Moon. Many Muslim communities now follow the Umm al-Qura Calendar of Saudi Arabia, which uses astronomical calculations to start months in a more predictable way. Using this calendar, sundown on Wednesday evening, May 8, will probably mark the beginning of Dhu al-Qadah, the eleventh month of the Islamic calendar. Dhu al-Qadah is also called “Master of Truces” and is one of the four sacred months in Islam during which warfare is prohibited (except in self defense). 

Thursday afternoon, May 9, 2024, will be when the planet Mercury reaches its greatest angular separation from the Sun as seen from the Earth for this apparition (called greatest elongation). Although Mercury will be bright enough to see in the glow of dawn, for this apparition it will not be above the horizon before morning twilight begins.

Sunday evening into early Monday morning, May 12 to 13, 2024, the bright star Pollux, the brighter of the twin stars in the constellation Gemini the twins, will be to the right of the waxing crescent Moon. Pollux will be 2.5 degrees from the Moon as evening twilight ends (at 9:18 PM EDT). By the time the Moon and Pollux set together on the northwestern horizon (at 1:14 AM) they will be 4 degrees apart. 

Wednesday morning May 15, 2024, the Moon will appear half-full as it reaches its first quarter at 7:48 AM EDT (when the Moon will be below our horizon). 

Friday afternoon, May 17, 2024, at 3 PM EDT, the waxing gibbous Moon will be at apogee, its farthest from the Earth for this orbit. 

Saturday afternoon, May 18, 2024, the bright planet Jupiter will be passing on the far side of the Sun as seen from the Earth, called conjunction. Because Jupiter orbits outside of the orbit of Earth it will be shifting from the evening sky to the morning sky and will begin emerging from the glow of dawn on the east-northeastern horizon in early June (depending upon viewing conditions).

Sunday evening into Monday morning, May 19 to 20, 2024, the bright star Spica will be near the waxing gibbous Moon. Spica will be 4.5 degrees to the lower left of the Moon as evening twilight ends (at 9:26 PM EDT). The Moon will reach its highest in the sky for the night an hour later (at 10:28 PM) with Spica 4 degrees to the lower left. By the time the Moon sets on the west-southwestern horizon (at 4:06 AM) Spica will be 2 degrees to the left of the Moon. 

The full Moon after next will be on Thursday morning, May 23, 2024, at 9:53 AM EDT. This will be on Friday morning from the Lord Howe time zone eastward to the International Date Line. The Moon will appear full for about three days around this time, from Tuesday night through early Friday evening. Thursday night the bright star Antares will appear so close to the Moon that for the Washington, DC area, the Moon will pass in front of Antares, blocking it from view, although the brightness of the full Moon will make it difficult to see the star vanish behind the Moon. 

BepiColombo spotted an outpour of carbon and oxygen atoms in Venus' fragile magnetic environment

Boeing Starliner astronauts spent hundreds of hours in simulators preparing for Crew Test Flight, which lifts off May 6. I got a brief taste of what they experienced.

One species of nematode worm turns into a kin-devouring nightmare if it grows up in a crowded environment with a poor diet

One species of nematode worm turns into a kin-devouring nightmare if it grows up in a crowded environment with a poor diet

The networks of fibre optic cables that criss-cross the planet could be used to better understand what’s happening inside it

The networks of fibre optic cables that criss-cross the planet could be used to better understand what’s happening inside it

NASA is asking its various research centers as well as private industry for new ideas about how to get Mars samples back to Earth relatively quickly and cost-effectively.

Water depths in Death Valley’s temporary lake ranged between about 3 feet (or 1 meter, shown in dark blue) to less than 1.5 feet (0.5 meters, light yellow) from February through early March. By measuring water levels from space, SWOT enabled research to calculate the depth.NASA/JPL-Caltech

Data from the international Surface Water and Ocean Topography mission helped researchers to calculate the depth of water in this transient freshwater body.

California’s Death Valley, the driest place in North America, has hosted an ephemeral lake since late 2023. A NASA-led analysis recently calculated water depths in the temporary lake over several weeks in February and March 2024, demonstrating the capabilities of the U.S.-French Surface Water and Ocean Topography (SWOT) satellite, which launched in December 2022.

The analysis found that water depths in the lake ranged from about 3 feet (1 meter) to less than 1.5 feet (0.5 meters) over the course of about 6 weeks. This period included a series of storms that swept across California, bringing record amounts of rainfall.

To estimate the depth of the lake, known informally as Lake Manly, researchers used water level data collected by SWOT and subtracted corresponding U.S. Geological Survey land elevation information for Badwater Basin.

The researchers found that the water levels varied across space and time in the roughly 10-day period between SWOT observations. In the visualization above, water depths of about 3 feet (1 meter) appear dark blue; those of less than 1.5 feet (0.5 meters) appear light yellow. Right after a series of storms in early February, the temporary lake was about 6 miles (10 kilometers) long and 3 miles (5 kilometers) wide. Each pixel in the image represents an area that is about 330 feet by 330 feet (100 meters by 100 meters).

To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video

Using data from SWOT, this video shows changes in water depth for Death Valley’s temporary lake from February into March of this year. Depths ranged between about 3 feet (1 meter) deep (dark blue) to less than 1.5 feet (0.5 meters) deep (light yellow). Credit: NASA/JPL-Caltech

“This is a really cool example of how SWOT can track how unique lake systems work,” said Tamlin Pavelsky, the NASA freshwater science lead for SWOT and a hydrologist at the University of North Carolina, Chapel Hill.

Unlike many lakes around the world, Death Valley’s lake is temporary, relatively shallow, and strong winds are enough to move the freshwater body a couple of miles, as happened from Feb. 29 to March 2. Since there isn’t typically water in Badwater Basin, researchers don’t have permanent instruments in place for studying water in this area. SWOT can fill the data gap for when places like this, and others around the world, become inundated.

Since shortly after launch, SWOT has been measuring the height of nearly all water on Earth’s surface, developing one of the most detailed and comprehensive views of the planet’s oceans and freshwater lakes and rivers. Not only can the satellite detect the extent of water, as other satellites can, but SWOT is also able to measure water surface levels. Combined with other types of information, SWOT measurements can yield water depth data for inland features like lakes and rivers.

The SWOT science team makes its measurements using the Ka-band Radar Interferometer (KaRIn) instrument. With two antennas spread 33 feet (10 meters) apart on a boom, KaRIn produces a pair of data swaths as it circles the globe, bouncing radar pulses off water surfaces to collect surface-height information.

“We’ve never flown a Ka-band radar like the KaRIn instrument on a satellite before,” said Pavelsky, so the data represented by the graphic above is also important for scientists and engineers to better understand how this kind of radar works from orbit.

More About the Mission

Launched in December 2022 from Vandenberg Space Force Base in central California, SWOT is now in its operations phase, collecting data that will be used for research and other purposes.

SWOT was jointly developed by NASA and the French space agency, CNES (Centre National d’Études Spatiales), with contributions from the Canadian Space Agency (CSA) and the UK Space Agency. NASA’s Jet Propulsion Laboratory, which is managed for the agency by Caltech in Pasadena, California, leads the U.S. component of the project. For the flight system payload, NASA provided the KaRIn instrument, a GPS science receiver, a laser retroreflector, a two-beam microwave radiometer, and NASA instrument operations. CNES provided the Doppler Orbitography and Radioposition Integrated by Satellite (DORIS) system, the dual frequency Poseidon altimeter (developed by Thales Alenia Space), the KaRIn radio-frequency subsystem (together with Thales Alenia Space and with support from the UK Space Agency), the satellite platform, and ground operations. CSA provided the KaRIn high-power transmitter assembly. NASA provided the launch vehicle and the agency’s Launch Services Program, based at Kennedy Space Center, managed the associated launch services.

To learn more about SWOT, visit:

https://swot.jpl.nasa.gov/

News Media Contacts

Jane J. Lee / Andrew Wang
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-0307 / 626-379-6874
jane.j.lee@jpl.nasa.gov / andrew.wang@jpl.nasa.gov

2024-043

Share

Details Last Updated Apr 15, 2024 Related Terms

• SWOT (Surface Water and Ocean Topography)
• Earth
• Earth Science
• Jet Propulsion Laboratory
• Water on Earth

Explore More 4 min read The Ocean Touches Everything: Celebrate Earth Day with NASA Article 4 days ago 3 min read Tech Today: Folding NASA Experience into an Origami Toolkit 

Math for designing lasers becomes artist’s key to creating complex crease patterns

Article 4 days ago 4 min read Media Get Close-Up of NASA’s Jupiter-Bound Europa Clipper Article 5 days ago