Astounding revelations have emerged as researchers, harnessing the remarkable capabilities of NASA’s James Webb Space Telescope, uncovered a captivating phenomenon: a captivating water vapor plume emanating from Saturn’s enchanting moon, Enceladus. This remarkable plume stretches a staggering distance of over 6,000 miles, equivalent to the approximate span between the vibrant cities of Los Angeles, California, and Buenos Aires, Argentina.

Webb is providing scientists with a first-ever direct view of how this water emission feeds the water supply for the entire Saturnian system and its rings. In a monumental stride for scientific discovery, never before have we witnessed such a captivating spectacle—a water emission of this magnitude stretching across an expansive distance.

Enceladus, a captivating oceanic world measuring a mere 313 miles in diameter and roughly 4% of Earth’s size, stands as an exceptionally alluring scientific pursuit within our solar system when it comes to the quest for alien life.

A vast pool of salty water sits between the moon’s rocky core and frozen outer surface. Informally known as “tiger stripes,” geyser-like volcanoes spray jets of ice particles, water vapor, and organic compounds out of the moon’s surface.

Observatories had previously measured moon jets hundreds of kilometers away, but Webb’s extraordinary sensitivity exposes a new story.

Saturn’s moon Enceladus
In this image, NASA’s James Webb Space Telescope shows a water vapor plume jetting from the southern pole of Saturn’s moon Enceladus, extending out 20 times the size of the moon itself. The inset, an image from the Cassini orbiter, emphasizes how small Enceladus appears in the Webb image compared to the water plume.
Credits: NASA, ESA, CSA, STScI, and G. Villanueva (NASA’s Goddard Space Flight Center). Image Processing: A. Pagan (STScI).

“When I was looking at the data, at first, I was thinking I had to be wrong. It was just so shocking to detect a water plume more than 20 times the size of the moon,” said lead author Geronimo Villanueva of NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The water plume extends far beyond its release region at the southern pole.”

The researchers were interested in more than just the plume’s length. It is also very astonishing how quickly the water vapor is erupting—about 79 gallons per second. At this pace, we’d have an Olympic-sized swimming pool filled in no time. On our beloved Earth, achieving the same feat with a garden hose would take over two weeks.

Throughout its decade-long exploration of the Saturnian system, the Cassini orbiter captured the first images of Enceladus’s plumes and even flew through them to collect samples of their constituent materials. While Cassini’s position within the Saturnian system gave it invaluable insights into this far-off moon, Webb’s singular view from the Sun-Earth Lagrange Point 2 and the astounding sensitivity of its Integral Field Unit aboard the NIRSpec (Near-Infrared Spectrograph) Instrument is providing new context.

“The orbit of Enceladus around Saturn is relatively quick, just 33 hours. As it whips around Saturn, the moon and its jets are basically spitting off water, leaving a halo, almost like a donut, in its wake,” said Villanueva. “In the Webb observations, not only was the plume huge, but there was just water absolutely everywhere.”

The dense “E-ring,” Saturn’s outermost and broadest ring, is present with the fuzzy torus of water that was observed to be “everywhere.”

The Webb observations clearly show how the torus is fueled by the moon’s water vapor plumes. According to an analysis of the Webb data, only around 30% of the water in this torus escapes, supplying the remaining 70% of the water in the Saturnian system.

Webb will be the main observatory for the ocean moon Enceladus in the coming years, and findings from Webb will help guide future solar system satellite missions that will try to investigate the depth of the underlying ocean, the thickness of the ice crust, and other things.

Water Vapor Plume
In this image, NASA’s James Webb Space Telescope’s instruments are revealing details into how one of Saturn’s moon’s feeds a water supply to the entire system of the ringed planet. New images from Webb’s NIRSpec (Near-Infrared Spectrograph) have revealed a water vapor plume jetting from the southern pole of Enceladus, extending out more than 20 times the size of the moon itself. The Integral Field Unit (IFU) aboard NIRSpec also provided insights into how the water from Enceladus feeds the rest of its surrounding environment.
Credits: NASA, ESA, CSA, STScI, Leah Hustak (STScI)

“Right now, Webb provides a unique way to directly measure how water evolves and changes over time across Enceladus’ immense plume, and as we see here, we will even make new discoveries and learn more about the composition of the underlying ocean,” added co-author Stefanie Milam at NASA Goddard. “Because of Webb’s wavelength coverage and sensitivity, and what we’ve learned from previous missions, we have an entire new window of opportunity in front of us.”

Guaranteed Time Observation (GTO) program 1250 was used to conclude Webb’s observations of Enceladus. This program’s first objective is to showcase Webb’s expertise in a certain scientific field and lay the groundwork for further research.

“This program was essentially a proof of concept after many years of developing the observatory, and it’s just thrilling that all this science has already come out of quite a short amount of observation time,” said Heidi Hammel of the Association of Universities for Research in Astronomy, Webb interdisciplinary scientist and leader of the GTO program.

As astronomers ventured into the depths of a hungry black hole, their gaze unveiled a remarkable sight—a fierce surge of X-rays erupting from it, boasting a temperature a staggering 60,000 times hotter than the surface of our very own sun.

Quasars are black holes that emit dazzling, energetic electromagnetic radiation jets from both sides when they consume the gases at the center of galaxies. The team’s X-ray photograph of a quasar known as SMSS J114447.77-430859.3 (J1144), is the most brilliant such object to have been spotted in the last 9 billion years of cosmic history. This amazing quasar radiates with intensity beyond our wildest dreams, outshining the sun’s brightness by an astounding factor of 100,000 billion. If you gaze upon the night sky amidst the celestial dance of Centaurus and Hydra, you may catch a glimpse of this celestial wonder, although it resides a mind-boggling distance of 9.6 billion light-years away.

The combined light from all the stars of the galaxies they are located in is frequently eclipsed by quasars like J1144 because they are so bright. They serve as instances of so-called active galactic nuclei (AGN), which are only discovered in the early cosmos and at great distances from Earth. Astronomers may gain a thorough understanding of these potent cosmic occurrences and the impact they have on their galaxy surroundings by studying the quasar.

Quasars are thought to be present in the early cosmos because galaxies at that time were richer in gas and dust, according to scientific theory. They had enough fuel to support dazzling emissions across nearly the entire electromagnetic spectrum, including low-energy radio, infrared, visible, ultraviolet, and high-energy X-ray wavelengths, thanks to their center black holes, which could be seen as a source of light.

SkyMapper Southern Survey (SMSS) first observed J1144 in the visible spectrum in 2022. The team, which was also directed by Ph.D. candidate Zsofi Igo from the Max Planck Institute for Extraterrestrial Physics (MPE), combined observations from various space-based observatories to further investigate this finding. These included the eROSITA instrument of the NASA Nuclear Spectroscopic Telescope Array (NuSTAR), the ESA XMM-Newton observatory, and the NASA Neil Gehrels Swift observatory.

By utilizing the amalgamation of data at our disposal, we were able to discern an astounding estimation regarding the temperature of the X-rays emanating from the quasars, indicating an astonishing value of approximately 630 million degrees Fahrenheit (350 million degrees Celsius). This is surprisingly startling 60,000 times hotter than the surface temperature of the sun.

Additionally, the diligent researchers conducted estimations to unveil the mass of the black hole, ultimately revealing a remarkable finding—a colossal magnitude weighing in at around 10 billion times the mass of our beloved sun. In addition, given how swiftly it devours stuff, J1144’s supermassive black hole is growing at a pace of 100 suns every year. The gas that surrounds this black hole is not all going into it, though.

The researchers found that a little amount of gas is being blasted from the quasar in the form of incredibly strong winds that are supplying a significant amount of energy to the galaxy it is located in.

The scientists also found that J1144 has a characteristic that sets it apart from other quasars: Its X-ray emission changes over just a few Earth days. The fluctuation of its X-rays would typically be on a timeframe of months or even years for a quasar with a black hole this big.

“We were very surprised that no prior X-ray observatory has ever observed this source despite its extreme power,” Kammoun added. “A new monitoring campaign of this source will start in June this year, which may reveal more surprises from this unique source.”

Astronomers have identified an Earth-size exoplanet, or globe outside our solar system, that may be covered in volcanoes. The planet, known as LP 791-18 d, may have volcanic outbursts as frequently as Jupiter’s moon Io, our solar system’s most volcanically active body. NASA’s TESS, Spitzer Space Telescope, and an array of ground-based observatories were used to find and study the planet.

earth size exoplanet
Astronomers discovered and studied the planet using data from NASA’s Spitzer Space Telescope and TESS (Transiting Exoplanet Survey Satellite) along with many other observatories. Credits: NASA’s Goddard Space Flight Center/Chris Smith (KRBwyle)

A report published on May 17:

A report describing the planet, led by Merrin Peterson, a graduate of the Trottier Institute for Research on Exoplanets (iREx) at the University of Montreal, was published in the scientific journal Nature on May 17.

Björn Benneke:

“LP 791-18 d is tidally locked, which means the same side always faces its star,” explained Björn Benneke, co-author and iREx astronomy professor who designed and supervised the project. “The day side is likely to be too hot for liquid water to exist on the surface.” However, the amount of volcanic activity that we suspect occurs all across the planet may be enough to sustain an atmosphere, allowing water to condense on the night side.”

LP 791-18 d:

LP 791-18 d circles a small red dwarf star in the southern constellation Crater, which is roughly 90 light-years away. According to the team, it is only slightly larger and heavier than Earth.

How does the size and weight of LP 791-18 d compare to the other planets in the system?

Prior to this discovery, astronomers were aware of two more worlds in the system known as LP 791-18 b and c. The inner planet b is around 20% the size of Earth. The outer planet c is around 2.5 times the size of Earth and weighs more than seven times as much.

What is the effect of the close passes of planet c on the planet d’s orbit and surface?

Planets d and c pass close to one other during each orbit. Each close pass by the more massive planet c causes a gravitational tug on planet d, causing its orbit to become slightly elliptical. Planet d is significantly distorted as it orbits the star on this elliptical course. These deformations have the potential to generate enough internal friction to significantly heat the planet’s innards and spark volcanic activity on its surface. Jupiter and some of its moons have similar effects on Io.

Where is planet d located in relation to the habitable zone?

Planet d is located on the outside of the habitable zone, which is the typical range of distances from a star at which astronomers believe liquid water may exist on the planet’s surface. If the planet is as geologically active as the researchers believe, it may be able to support life. Temperatures on the planet’s night side may fall low enough for water to condense on the surface.

James Webb Space Telescope observation:

Planet c has already been cleared for James Webb Space Telescope observing time, and the team believes planet d is an excellent candidate for atmosphere investigations by the mission.

Jessie Christiansen:

“A big question in astrobiology, the broad study of the origins of life on Earth and beyond, is whether tectonic or volcanic activity is required for life,” said co-author Jessie Christiansen, a research scientist at NASA’s Exoplanet Science Institute at the California Institute of Technology in Pasadena. “In addition to potentially providing an atmosphere, these processes could churn up materials that would otherwise sink and become trapped in the crust, including those we believe are essential for life, such as carbon.”

Spitzer Observation:

Spitzer’s observations of the system were among the last data points collected by the satellite before it was retired in January 2020.

Joseph Hunt:

“It’s incredible to read about the continued discoveries and publications years after Spitzer’s mission concluded,” said Joseph Hunt, Spitzer project manager at NASA’s Jet Propulsion Laboratory in Southern California. “This demonstrates the accomplishments of our world-class engineers and scientists.” They collaborated to build not only a spacecraft but also a data set that is still useful to the astrophysics community.”

Who are the collaborators and partners involved in the TESS mission?

TESS is a NASA Astrophysics Explorer mission led and administered by MIT in Cambridge, Massachusetts. Northrop Grumman in Falls Church, Virginia; NASA’s Ames Research Center in California’s Silicon Valley; the Center for Astrophysics | Harvard & Smithsonian in Cambridge, Massachusetts; MIT’s Lincoln Laboratory; and the Space Telescope Science Institute in Baltimore are among the other collaborators. The mission includes more than a dozen colleges, research institutes, and observatories from around the world.

Where is the Spitzer data archive located and who oversees it?

The Spitzer data archive, which is kept at the Infrared Science Archive at IPAC at Caltech in Pasadena, California, houses the whole body of scientific data produced by Spitzer during its existence. Spitzer mission operations were overseen for NASA’s Science Mission Directorate in Washington by Caltech’s Jet Propulsion Laboratory. The Spitzer Science Center at IPAC at Caltech was the site of the science operations. Lockheed Martin Space in Littleton, Colorado was responsible for spacecraft operations.

Following its groundbreaking cloud-imaging mission last month, NASA’s Curiosity rover continues to astound scientists with captivating observations, including the recent discovery of a hardcover-shaped feature on April 15, marking the mission’s 3,800th Martian day (or sol). Geologists, akin to meticulous librarians, carefully examine the evidence surrounding them to unravel the mysteries of Mars’ past. NASA officials suggest that the distinctive shape of rocks like this one is typically attributed to water flowing through the region billions of years ago, during a time when the Red Planet boasted a significantly wetter environment.

What did JPL reveal about the discovery regarding wind erosion?

The world is now considerably drier and windier. “After eons of being sand-blasted by the wind, softer rock is carved away, and the harder materials are all that’s left,” NASA’s Jet Propulsion Laboratory (JPL) in Southern California, which manages Curiosity’s mission, revealed of the discovery on Thursday (May 11).

J. Paul Getty Museum:

While writing is supposed to have started in ancient Sumer (near the modern-day Persian Gulf) some 5,400 years ago, the manner in which humans record information is numerous, according to the J. Paul Getty Museum. 

What is the argument presented by the 2023 study regarding the “dots” in a cave picture?

One 2023 study argues that the “dots” in a cave picture could be a kind of writing from 20,000 years ago, while the conclusion is debatable. Modern forms of writing have been placed on rock walls, clay tablets, and scrolls, to name a few reading styles. 

British Library:

According to the British Library, what we now term “books” began with codices, initially as wax tablets and subsequently as parchment in the Mediterranean and Mesopotamian areas. Dating is difficult, but the format has been quite common in Greco-Roman times, if not before.

According to JPL, Curiosity has been exploring Mars’ Gale Crater since August 2012, with critical results in science papers including the discovery of persistent liquid water on ancient Mars, potential evidence of old life through organics, and examinations of radiation at the surface.

What is the purpose of the Perseverance mission on Mars?

Perseverance, a successor mission, is working in the Jezero Crater area of Mars, caching tubes (or lightsabers) of samples for future return to Earth. The sample return effort is scheduled to pick up with the launch of a relay spacecraft and a handful of mini-helicopters in the late 2020s.

In the center of this photograph taken by the NASA/ESA Hubble Space Telescope lies a massive galaxy cluster.  This huge cosmic creature can be detected by looking at the ripples it creates in spacetime. It’s like a sea monster swimming beneath the surface of the ocean. The cluster is so big that it bends the light from faraway galaxies, making them look different. This image shows twisted lines and curves of light. The cluster is surrounded by many other galaxies, and there are a few stars in the foreground that have diffraction spikes.

galaxy cluster
Image credit: ESA/Hubble & NASA, H. Ebeling

What is the significance of eMACS J1823.1+7822?

The galaxy cluster eMACS J1823.1+7822 is located in the Draco constellation and is almost nine billion light-years away. Hubble studied five really big galaxy clusters to measure how strong their gravitational lenses are. This helps us understand where dark matter is in these clusters. 

How can gravitational lenses help astronomers study faraway galaxies?

Gravitational lenses, such as eMACS J1823.1+7822, can help astronomers study faraway galaxies. These lenses act like giant telescopes, making faint or distant objects appear bigger and clearer.

What instruments were used to capture the image of the galaxy cluster and how do they work?

This picture combines information from eight filters and two instruments: Hubble’s Advanced Camera for Surveys and Wide Field Camera 3. Both instruments can see space objects by using filters that capture specific wavelengths of light. This helps astronomers take pictures of objects at precise wavelengths. Astronomers use different types of observations to get a better understanding of an object’s structure, composition, and behavior. This helps them see more than what visible light alone can show.

Scientists have used earthquake data to discover that the Moon’s inner core is a solid ball with the same density as iron. The finding settled the controversy over whether the Moon’s inner core is solid or liquid and may help explain its history and the Solar System. Astronomer Arthur Briaud and his team from the French National Centre for Scientific Research used data from space missions and lunar laser ranging tests to map the Moon’s features and found that its core is similar to Earth’s, with a fluid layer on the outside and a solid core in the middle.

Moon’s inner core – A solid ball of Iron:

A thorough study has shown that the Moon’s inner core is a solid ball with the same density as iron. Scientist aims to end this long-running debate about whether the Moon’s inner core is solid or liquid and lead. For better acknowledgment of the Moon’s history and, by extension, the history of the entire Solar System.

“Our results,” writes a team led by astronomer Arthur Briaud of the French National Centre for Scientific Research in France, “question the evolution of the Moon magnetic field thanks to its demonstration of the existence of the inner core and support a global mantle overturn scenario that brings substantial insights on the timeline of the lunar bombardment in the first billion years of the Solar System.”

How did scientists find out about the Moon’s inner core?

Using earthquake data is the best way to find out what things are made of on the inside of the Solar System. Scientists can make a detailed map of the inside of a planet or moon by looking at how quakes send out acoustic waves that move through and bounce off of the stuff inside.

Apollo Mission:

We have acoustic data from the moon that was collected by the Apollo mission, but it’s not clear enough to tell what’s going on in the inner core. We know there is a flowing outer core, but no one can agree on what it is. Based on the Apollo data, both models of a solid inner core and a core made of only fluids work well.

Briaud and his colleagues put together a profile of the moon’s different features using data from space missions and lunar laser ranging tests. They did this to find out the answer for sure. Some of these are how much its shape is changed by Earth’s gravity, how its distance from Earth changes, and how dense it is.

Moon's inner core
Artist’s impression of different instruments measuring the properties of the Moon to reveal its core. (Géoazur/Nicolas Sarter)

Next, they did models with different types of cores to see which one fit the observational data the best.

What did the researchers find about the density and size of the Moon’s inner core?

They found out a lot of interesting things. First, the models that best fit what we know about the Moon show that deep inside the lunar crust, there is a lot of activity. This means that the dense stuff inside the Moon sinks toward the center, while the less dense stuff rises. This has been suggested for a long time as a way to explain why some elements are found in volcanic areas of the Moon. The study done by the team is another piece of evidence that shows that “for” is right.

Fluid Outer layer:

And they found that the moon’s core is a lot like Earth’s, with a fluid layer on the outside and a solid core in the middle. According to the research, the outer core is about 362 kilometers (225 miles) in diameter. However, the diameter of the inner core is about 258 kilometers (160 miles). That is about 15 percent of the Moon’s whole diameter.

The team found that the density of the inner core is also about 7,822 kg per cubic meter. That’s a lot like how heavy iron is.

What did a previous study in 2011 found about the Moon’s inner core?

In 2011, a team led by NASA Marshall planetary scientist Renee Weber using Apollo data and the most advanced seismological methods at the time to study the lunar core found the same thing. They discovered a solid inner core around 240 km in diameter and 8,000 kg/m3.

A study done by Briaud:

Briaud and his team say that their results back up those earlier ones and make a pretty good case for a lunar core like Earth’s. This reveals interesting changes in the Moon throughout time.

Why is knowing about the Moon’s inner core important?

The Moon had a strong magnetic field shortly after its formation. This field began to weaken about 3.2 billion years ago. This kind of magnetic field is caused by movement and convection in the core, so knowing what the lunar core is made of is very important for understanding how and why the magnetic field vanished. Since people hope to go back to the Moon soon, we might not have to wait long for seismic proof of these results.

Astronomers have discovered a giant black hole at the center of Messier 84 “M84” (a massive elliptical galaxy). This giant black hole is leaving an “H”-shaped structure in the multimillion-degree gas around it. Using NASA’s Chandra X-ray Observatory, researchers mapped the hot gas in and around M84. This reveals the letter “H” formed by cavities in the hot gas around the black hole created by jets of particles blasted away from the black hole. The study also shows that the jets may affect the flow of hot gas toward the black hole, slowing the rate at which gas falls onto it. The results were reported in the Royal Astronomical Society Monthly Notices.

With what appears to be a single letter etched into the X-ray glow surrounding it, a massive black hole at the center of an elliptical galaxy is leaving its imprint on its surroundings.

The H-shaped Structure in M84’s Gas Cavity:

A comprehensive new X-ray map of the multimillion-degree gas surrounding the galaxy Messier 84 (M84) reveals this “H”-shaped structure. As gas is captured by the black hole’s gravitational force, a portion of it will descend into the abyss, never to be seen again. Some of the gas, however, escapes this fate by being expelled from the black hole in the form of particle streams. These projectiles can eject holes from the hot gas surrounding the black hole. 

Given the orientation of the jets toward Earth and the profile of the heated gas, it appears that the cavities in Messier 84 resemble the letter “H.” The H-shaped structure in the gas is an illustration of pareidolia, which occurs when individuals perceive familiar shapes or patterns in random data. Pareidolia can occur in all types of data, including images of clouds, mountains, and astronomical objects.

messier 84
Credits: X-ray: NASA/CXC/Princeton Univ/C. Bambic et al.; Optical: SDSS; Radio: NSF/NRAO/VLA/ESO; Image processing: NASA/CXC/SAO/N.Wolk

What is the significance of the NASA Chandra X-ray Observatory?

Using NASA’s Chandra X-ray Observatory, astronomers created a map of the hot plasma (pink) in and around Messier 84, reaching within 100 light-years of the central black hole of the galaxy. This gas radiates at temperatures in the tens of millions of degrees, allowing X-rays to be its primary mode of observation. The enormous letter “H” is approximately 40,000 light-years tall, or roughly half of the Milky Way’s girth. 

The radio image from the Karl G. Jansky Very Large Array (VLA) of the National Science Foundation (blue) reveals the plumes emanating from the black hole. Sloan Digital Sky Survey optical data (white) depicts M84 and neighboring galaxies. The letter H and the black hole’s location are labeled. A further image depicts a zoomed-in view of the region marked with a square, as well as distinct labels for the galaxy and jets in the optical and radio images, respectively.

Do jets have a greater influence on the flow of matter towards a black hole than the black hole’s gravitational pull in Messier 84?

Jets may influence the flow of hot gas toward the black hole even more than the black hole’s gravitational pull, according to researchers investigating M84 with Chandra and the VLA. For instance, the team estimates that matter falls towards the black hole from the north — along the direction of the jet seen in radio waves — at a rate of approximately 500 times the mass of the Earth per year, compared to a rate that is only a quarter of that from directions where the jet is not pointing, such as the east and west. The cavities may lift gas in the direction of the jet, slowing the rate at which gas descends onto the black hole.

The Bondi accretion mode:

The authors tested the Bondi accretion model, in which all matter within a certain distance from a black hole — effectively within a sphere — is near enough to be affected by a black hole’s gravity and begin falling inwards at the same rate from all directions. (The dashed circle in the close-up image is centered on the black hole and indicates the approximate distance at which gas should begin to descend inwards.) 

This effect is named after the astronomer Hermann Bondi, and “accretion” refers to matter plummeting into a black hole. The new results indicate that Bondi accretion is not occurring in Messier 84 because the matter is not descending uniformly from all directions into the black hole.

How does the black hole in Messier 84 compare to the one in M87?

Both Messier 84 and Messier 87 are located in the Virgo Cluster and contain supermassive black holes. The black hole in M87 was the first one captured by the Event Horizon Telescope network, while the black hole in M84 is one of the few black holes close enough to Earth for astronomers to study in detail. 

While both black holes produce a discharge of particles, the point source of X-rays from material closer to the black hole is over ten times fainter in M84 than in M87. This allows astronomers to analyze gas falling towards the black hole in Messier 84 that is further away, as the faint X-rays produced by this gas are not overwhelmed by the X-ray glare from the point source.

The publication of the analysis:

The Monthly Notices of the Royal Astronomical Society will publish a paper describing these results, and a preprint is available here. Christopher Bambic, a graduate student at Princeton University, directed the research along with other authors.

It is now the moon’s turn to experience an eclipse, little over two weeks after its shadowy figure crossed in front of the sun over portions of the Pacific Ocean, New Guinea, and the Indian Ocean. On May 5, the moon almost totally disappears beneath the Earth’s shadow, leaving only the penumbra, the shadow’s outermost region. The penumbra is not only light in color, but it also gets lighter as it moves farther from the umbra, the shadow’s black center region. Consequently, this occurrence is known as a penumbral lunar eclipse.

When will the penumbral lunar eclipse start?

On Friday, May 5, the penumbral lunar eclipse will start at 11:13 a.m. EDT (15:13 GMT) and peak at 1:24 p.m. EDT (17:24 GMT). When the moon comes out from the Earth’s shade at 3:31 p.m. EDT (1932 GMT), the eclipse will be over.

No portion of the moon crosses into the Earth’s deep umbral shadow during a penumbral lunar eclipse, leaving no visible trace of the Earth’s shadow. This brief eclipse won’t have much of an impact on the moon’s brightness because it will pass through the farthest reaches of the Earth’s shadow. Unless at least two-thirds of the moon’s disk are completely submerged within it, the penumbral shadow is typically faint and challenging to see. Even though the area of the moon closest to the much darker umbral shadow may darken rationally, it might not draw attention.

Penumbral Lunar Eclipse
A map showing the worldwide visibility of the lunar eclipse on May 5, 2023. (Image credit: Dominic Ford/

The Earth would appear to partially shade the sun to an astronaut standing on the moon. 

Which region won’t be able to view the eclipse?

The Eastern Hemisphere benefits from this eclipse, especially a portion of eastern Africa and neighboring Madagascar as well as most of western Asia. The moon will be below the horizon during the daytime when this event takes place, thus the Americas won’t see any of it. The moon’s course will be to the north of the deep umbral shadow.

What are the key features of the upcoming penumbral eclipse?

The moon will begin to enter the penumbral shadow at the time shown in the timeline below, which has been adjusted to reflect Greenwich Mean Time (GMT), however, nothing exceptional will be visible on the lunar disk at that time. 

The penumbral lunar eclipse magnitude, or the portion of the moon’s diameter that is under the lighter penumbral shadow, will be 96.4 percent at the time of the eclipse’s darkest phase. 

Moon’s proximity to Earth’s shadow during the eclipse:

When the moon is in the southern part of the penumbra, there will be just around 78 miles (126 km) between its highest edge and Earth’s umbra.  Therefore, those who know to look may be able to see a vague grayish or brownish smudge or stain concentrated toward the moon’s upper rim for about 45 minutes, or so, around the time of the middle of the eclipse. 

Which areas will be able to see the eclipse?

Eastern Asia, Indonesia, Australia, and southern New Zealand will also be able to see the eclipse, but because it happens after local midnight there, Saturday (May 6) will appear on the calendar. The moon will set in New Zealand and parts of Japan while still completely engulfed by the penumbral shadow. 

Those who won’t be able to view the eclipse:

The rest of the world won’t be able to see the eclipse because it will happen during the day and the moon will be below the horizon. Try not to worry too much if that relates to you. After all, this event pales in comparison to more spectacular celestial displays like the recent uncommon hybrid solar eclipse that occurred on April 20.

An expanding dying star devours a Jupiter-sized planet. In approximately 5 billion years, our Sun will undergo a similar end-of-life phase.

What is the significance of the recent observation in which an aging star devours a planet?

The first time an aging star ate a planet was seen in a new study that came out online on May 3 in the magazine Nature. The star’s core ran dry, and it began to expand, closing the distance to the neighboring planet until it absorbed it totally. In around 5 billion years, our Sun will undergo a similar aging process, expanding to a diameter perhaps 100 times that of today and becoming a red giant. During that period of rapid expansion, it will swallow up Mercury, Venus, and maybe even Earth.

While it had been speculated by astronomers that some red giant stars eat planets in their vicinity, this had never been directly observed until now. “This type of event has been predicted for decades, but until now we have never actually observed how this process plays out,” said Kishalay De, an astronomer at the Massachusetts Institute of Technology in Cambridge and the study’s lead author.

What is ZTF SLRN-2020, and how did NEOWISE uncover this phenomenon?

NASA’s Jet Propulsion Laboratory-managed NEOWISE (Near-Earth Object Wide Field Infrared Survey Explorer) spacecraft and a network of ground-based observatories uncovered the phenomenon, which has been given the formal name ZTF SLRN-2020.  The planet was probably about the size of Jupiter, and it circled its star even closer than Mercury does around our Sun. The red giant phase of the star’s life, which can continue for more than 100,000 years, has just begun.

The outer atmosphere of the star grew to encompass the planet as it grew in size. The planet’s orbit shrank due to atmospheric drag, causing it to disappear below the star’s visible surface, much like a meteor that burns up in Earth’s atmosphere. Because of the energy exchange, the star temporarily grew in size and brightness by a factor of about a hundred. The star’s size and brightness are back to what they were before the planetary merger, according to recent observations.

The gradual demise of a planet orbiting a growing host star is illustrated in this video. The planet pulls a spray of gas away from the star as it spirals closer. Once the planet is devoured, the star grows in brightness and size, but will eventually return to how it was before the merger.
Credits: R. Hurt & K. Miller (Caltech/IPAC)


How did Zwicky Transient Facility contribute to the observation of a unique astronomical event?

The Zwicky Transient Facility (ZTF), a Palomar Observatory instrument led by Caltech that searches for astronomical events with rapid changes in brightness (sometimes in a matter of hours), detected the burst of optical light (visible to the human eye) that followed the planet’s demise. De was using ZTF to look for novae, which occur when one star’s hot gas is consumed by another star’s dead, collapsed core (called a white dwarf). Even though novae are always surrounded by flows of hot gas, subsequent ground-based telescope observations of the flash revealed much cooler gas and dust surrounding the star, making it look unlike anything De had ever seen before.

As a result, he looked to the NEOWISE observatory, which does a six-monthly infrared (light with longer wavelengths than visible) survey of the whole sky. The observatory, officially called WISE when it was released in 2009, creates maps of the whole sky that show astronomers the evolution of objects through time.

Thanks to the combined efforts of ZTF and NEOWISE, astronomers were able to observe and study this rare event in great detail, shedding new light on the process of star devours and the formation of cosmic structures.

Observation and analysis of NEOWISE:

De examined the NEOWISE data and discovered that the star brightened nearly a year before the flash was discovered by ZTF. Dust (which emits infrared light) was accumulating around the star, explaining the apparent brightening. Dust, according to De and coworkers, shows that the planet put up a struggle before collapsing under its own weight as the bloated star drifted to its death. The gas would have cooled as it traveled across space, turning into dust in much the same way that water vapor condenses into snow. More gas was ejected into space during the star-planet collision, resulting in more dust seen by NEOWISE and ground-based infrared sensors.

“Very few things in the universe brighten in infrared light and then brighten in optical light at different times,” said De. “So the fact that NEOWISE saw the star brighten a year before the optical eruption was critical to figuring out what this event was.”

Kishalay De prediction:

Since the planets Mercury, Venus, and Earth are many times smaller than the Jupiter-size planet in the ZTF-captured event, De predicts that the light show will be much more subdued when our Sun becomes a red giant and star devours Mercury, Venus, and possibly Earth in five billion years.

“If I were an observer looking at the solar system 5 billion years from now, I might see the Sun brighten a little, but nothing as dramatic as this, even though it will be the exact same physics at work,” he said.

What does the recent discovery of a planet-eating star mean for astronomers and their observations?

Theorists believe that a small number of neighboring planets are consumed each year by red giants, the final stage of evolution for most mid-size stars. Astronomers now have a benchmark for what further such occurrences should look like, thanks to the new data.

Joe Masiero – Deputy main investigator for NEOWISE:

According to Joe Masiero, deputy main investigator for NEOWISE at IPAC at Caltech, “This discovery shows that it’s worthwhile to take observations of the entire sky and archive them because we don’t yet know all of the interesting events we might be capturing.” The NEOWISE database provides a convenient way to do just that. If we look hard enough, we might discover some buried treasure or piece of information about an object that no other observatory has uncovered.

Despite the development of advanced technologies by space agencies such as NASA and ESA for asteroid tracking and monitoring, the very first discovery of an asteroid was accidental. It was made by astronomer Giuseppe Piazzi in 1801 while he was making a star map, and he named the object Ceres. With a diameter of about 1000 kilometers (twice the length of New York State), Ceres is also the largest asteroid ever observed. While it’s not as big as Ceres, NASA has issued a warning about an asteroid 2023 HY3 that is expected to come closest to Earth today.

Will Asteroid 2023 HY3 going to hit the Earth?

This asteroid will pass extremely close to Earth, but it is not thought to pose any threat of collision. NASA estimates that Asteroid 2023 HY3 will be about 6.3 million km from Earth as it passes by. It has reached a velocity of 23596 km/h.

Who is monitoring the Asteroid 2023 HY3?

NASA’s Planetary Defence Coordination Office keeps an eye out for Near-Earth Objects (NEOs) that could cause any damage to Earth. An asteroid known as 2023 HY3 has been the subject of a warning from the group. Today, May 1, is when this NEA will get rather close to our planet.

Like its given name, asteroid 1221 Amor, 2023 HY3 is a member of the Amor group of asteroids, which consists of Earth-approaching near-Earth asteroids with orbits outside Earth’s but within Mars’.

Is NASA also involved in the ground based observation as well?

NASA uses a number of ground-based telescopes to observe and analyze far-off asteroids. These telescopes include the Atacama Large Millimeter/submillimeter Array (ALMA) in the Antofagasta Region of the Atacama Desert in Chile.

In addition, NASA has implemented a new impact monitoring system that employs an algorithm dubbed Sentry-Il to determine the potential threat posed by Near-Earth Objects. Using this infrared data, NASA can monitor the asteroid’s orbit and make predictions about its path years in the future. Nearly 28,000 Earth-approaching asteroids have been spotted by various sky-tracking technologies so far.