Universe Today

Universe Today has recently had the privilege of investigating a myriad of scientific disciplines, including impact craters, planetary surfaces, exoplanets, astrobiology, solar physics, comets, planetary atmospheres, planetary geophysics, cosmochemistry, meteorites, radio astronomy, and extremophiles, and how these multidisciplinary fields can help both scientists and space fans better understand how they relate to potentially finding life beyond Earth, along with other exciting facets. Here, we will examine the incredible field of organic chemistry with Dr. Andro Rios, who is an Assistant Professor in Organic Chemistry at San José State University, regarding why scientists study organic chemistry, the benefits and challenges, finding life beyond Earth, and potential paths for upcoming students. So, why is it so important to study organic chemistry?

“Organic chemistry is a fascinating and powerful discipline that is directly connected to nearly everything we interact with on a daily basis,” Dr. Rios tells Universe Today. “This can range from what gives our favorite foods the flavors we love, to the medicines we take to help alleviate our pain. Organic chemistry is also the basis of describing the known chemistry that makes up the biology on this planet (called biochemistry) and can possibly provide the clues to what extraterrestrial life might be based on as well, should we find evidence of it in the upcoming years.”

While its name implies a scientific field of complicated science, the field of organic chemistry essentially involves the study of organic compounds, also known as carbon-based life, which comprises all known lifeforms on the Earth. This involves studying the various properties, classifications, and reactions that comprise carbon-based life, which helps scientists understand their structural formulas and behaviors. This, in turn, enables overlap with other disciplines, including the aforementioned biochemistry, but also includes materials science, polymer chemistry, and medicinal chemistry, as well. Therefore, given its broad range of scientific potential, what are some of the benefits and challenges of studying organic chemistry?

“Organic chemistry has played a vital role in transforming the human experience on this planet by improving our health and longevity,” Dr. Rios tells Universe Today. “All of us, or nearly all of us, have known either family members, friends or even ourselves who have fallen severely ill or battled some chronic disease. The development of new medicines, both directly and indirectly through the tools of organic chemistry to fight these ailments has been one of the most beneficial contributions of this field to society.”

Dr. Rios continues, “Learning organic chemistry in the classroom often presents a challenge because it seems so different from the general chemistry courses that most students have learned to that point. The reason for this is because organic chemistry introduces new terminology, and its focus is heavily tied to the 3-dimensional structure and composition of molecules that is not considered in general chemistry courses. The good news is that organic chemistry provides the perfect bridge from general chemistry to biochemistry/molecular biology which also often focuses on the structures and shapes of molecules (biomolecules).”

The field of organic chemistry was unofficially born in 1807 by the Swedish chemist, Jöns Jacob Berzelius, after he coined the term when describing the origins of living, biological compounds discovered throughout nature. However, this theory was disproven in 1828 by the German scientist, Friedrich Wöhler, who discovered that organic matter could be created within a laboratory setting. It took another 33 years until the German chemist, Friedrich August Kekulé von Stradonitz, officially defined organic chemistry in 1861 as a subfield of chemistry involving carbon compounds. Fast forward more than 160 years later to the present day, and the applications of organic chemistry has expanded beyond the realm of the living and can be found in almost every scientific, industrial, commercial, and medical field throughout the world, including genetics, pharmaceuticals, food, and transportation.

As noted, the very basis of organic chemistry involves the study of carbon-based life, which is the primary characteristic of life on our small, blue world. The reason is because the structure of carbon can form millions of compounds due to their valence electrons that allow it to bond with other elements, specifically hydrogen and oxygen, but can also bond with phosphorus, nitrogen, and sulfur (commonly referred to as CHNOPS).

While carbon-based life is the most common form of life on Earth, the potential for silicon-based life has grabbed the attention of scientists throughout the world due to their similar bonding characteristics as carbon. However, certain attributes, including how it shares electrons (known as electropositivity), prevent it from being able to form lifelike attributes. Therefore, if carbon-based life is currently the primary characteristic of all life on Earth, what can organic chemistry teach us about finding life beyond Earth?

“Life on Earth is highly selective in its utility of organic compounds, both big and small, which is an outcome of biological evolution on this planet,” Dr. Rios tells Universe Today. “But over the years detailed studies on the properties (reactivity, function, preservation, etc) of these molecules and polymers have revealed to us that there is nothing inherently ‘special’ about those biochemicals compared to those that aren’t associated with life (called abiotic chemistry).”

Dr. Rios continues, “What we have learned, however, is that there are trends, or patterns in the selectivity of molecules used by life that might be helpful in informing us not only how life emerged on this planet, but in the search for life elsewhere. This suggests that when we go looking for life in other worlds, we shouldn’t necessarily expect to find the same biochemical make-up we see in our terrestrial biology. Rather, we should be keeping a lookout for any patterns or trends in the chemical make-up of alien environments that are distinct from what we might consider typical abiotic chemistry.”

As noted, the science of organic chemistry is responsible for myriad of applications throughout the world, which are accomplished through the creation of new compounds. One of the most well-known applications for organic chemistry is the pharmaceutical industry and the development of new drugs and treatments, including aspirin which is one of the most well-known drugs throughout the world. Additionally, organic chemistry is responsible for everyday products, including biofuels, biodegradable plastics, agriculture, and environmental purposes. Therefore, with the wide range of applications for organic chemistry, including the potential to find life beyond Earth, what is the most exciting aspect of organic chemistry that Dr. Rios has studied during his career?

“For me, it was when I was in graduate school when I made the realization that I could apply the knowledge and tools of organic chemistry that I was studying in the lab, to questions that were relevant to astrobiology,” Dr. Rios tells Universe Today. “I am particularly interested in questions surrounding prebiotic chemistry, chemical evolution and the origin of life. The primary area that captivates my interest within the origin of life field is metabolic chemistry —exploring the origins of metabolism. This field, known as protometabolic chemistry, has been gaining momentum in recent years. Our community has been uncovering that small prebiotic molecules have the ability, under a wide range of conditions, to initiate simple reaction networks that can lead to more complex molecules over time. These results are exciting because they are potentially helping us understand the origin of one of biology’s most complex processes.”

The individuals who study organic chemistry are aptly called organic chemists who spend time designing and creating new organic compounds for a variety of purposes. This frequently involves examining the myriad of structural drawings of organic compounds and learning how each one functions individually and adding or subtracting new elements to create new compounds. Like most scientific disciplines that Universe Today has examined throughout this series, organic chemistry is successful through the constant collaboration with other fields with the goal of gaining greater insight into life and the world around us, including beyond Earth. Therefore, what advice would Dr. Rios give to upcoming students who wish to pursue studying organic chemistry?

Dr. Rios tells Universe Today, “Organic chemistry is a discipline that fundamentally interacts with so many other fields of STEM; biology, medicine, synthetic biology, bioengineering, chemical engineering, ecology, etc. Taking the time to devote a portion of your education in learning the language of this discipline will be one of the most important intellectual investments you will make in your STEM related career.”

How will organic chemistry help us better understand our place in the cosmos in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

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The Milky Way is ancient and massive, a collection of hundreds of billions of stars, some dating back to the Universe’s early days. During its long life, it’s grown to these epic proportions through mergers with other, smaller galaxies. These mergers punctuate our galaxy’s history, and its story is written in the streams of stars left behind as evidence after a merger.

And it’s still happening today.

The Milky Way is currently digesting smaller galaxies that have come too close. The Large and Small Magellanic Clouds feel the effects as the Milky Way’s powerful gravity distorts them and siphons a stream of gas and stars from them to our galaxy. A similar thing is happening to the Sagittarius Dwarf Spheroidal Galaxy and globular clusters like Omega Centauri.

There’s a long list of these stellar streams in the Milky Way, though the original galaxies that spawned them are long gone, absorbed by the Milky Way. But the streams still tell the tale of ancient mergers and absorptions. They hold kinematic and chemical clues to the galaxies and clusters they spawned in.

As astronomers get better tools to find and study these streams, they’re realizing the streams could tell them more than just the history of mergers. They’re like strings of pearls, and their shapes and other properties show how gravity has shaped them. But they also reveal something else important: how dark matter has shaped them.

Since dark matter is so mysterious, any chance to learn something about it is a priority. As researchers examine the stellar streams, they’re finding signs of disturbances in them—including missing members—that aren’t explained by the Milky Way’s mass. They suspect that dark matter is the cause.

“If we find a pearl necklace with a few scattered pearls nearby, we can deduce that something may have come along and broken the string.”

Soon, astronomers will have an enormously powerful tool to study these streams and dark matter’s role in disturbing them: the Vera Rubin Observatory (VRO).

Astronomers have different methods of studying dark matter. Weak gravitational lensing is one of them, and it maps dark matter on the large scale of galaxy clusters. But stellar streams are at the opposite end of the scale. By mapping them and their irregularities and disturbances, astronomers can study dark matter at a much smaller scale.

This image shows the core of the Sagittarius Dwarf Spheroidal Galaxy and its stellar streams as it’s absorbed by the Milky Way. Image Credit: David Law/UCLA

The Rubin Observatory will complete its Legacy Survey of Space and Time (LSST) in a ten-year period. Alongside its time-domain astronomy objectives, the LSST will also study dark matter. The LSST Dark Energy Science Collaboration is aimed at dark matter and will use Rubin’s power to advance the study of dark energy and dark matter like nothing before it. “LSST will go much further than any of its predecessors in its ability to measure the growth of structure and will provide a stringent test of theories of modi?ed-gravity,” their website explains.

As we get closer and closer to the observatory’s planned first light in January 2025, the growing excitement is palpable.

“I’m really excited about using stellar streams to learn about dark matter,” said Nora Shipp, a postdoctoral fellow at Carnegie Mellon University and co-convener of the Dark Matter Working Group in the Rubin Observatory/LSST Dark Energy Science Collaboration. “With Rubin Observatory we’ll be able to use stellar streams to figure out how dark matter is distributed in our galaxy from the largest scales down to very small scales.”

Astronomers have ample evidence that a halo of dark matter envelops the Milky Way. Other galaxies are the same. These dark matter halos extend beyond a galaxy’s visible disk and are considered basic units in the Universe’s large-scale structure. These haloes may also contain sub-haloes, clumps of dark matter bound by gravity.

This image shows a simulated Milky Way-size CDM halo. The six circles show sub-haloes enlarged in separate boxes. Sub-haloes are also visible, and the bottom row shows several generations of sub-subhaloes contained within subhalo f. Image Credit: Zavala and Frenk 2019

These clumps are what astronomers think are leaving their marks on stellar streams. The dark matter clumps create kinks and gaps in the streams. The VRO has the power to see these irregularities on a small scale and over a ten-year span. “By observing stellar streams, we’ll be able to take indirect measurements of the Milky Way’s dark matter clumps down to masses lower than ever before, giving us really good constraints on the particle properties of dark matter,” said Shipp.

The Lambda Cold Dark Matter (Lambda CDM) model is the standard model of Big Bang Cosmology. One of the Lambda CDM’s key predictions says that many sub-galactic dark matter substructures should exist. Astronomers want to test that prediction by observing these structures’ effect on stellar streams. The VRO will help them do that and will also help them find more of them and build a larger data set.

Stellar streams are difficult to detect. Their kinematics give them away, but sometimes, there are only a few dozen stars in the streams. This obscures them among the Milky Way’s myriad stars. But the VRO will change that.

The VRO will detect streams at much further distances. On the outskirts of the Milky Way, the streams have interacted with less matter, making them strong candidates for studying the effect of dark matter in isolation.

“Stellar streams are like strings of pearls, whose stars trace the path of the system’s orbit and have a shared history,” said Jaclyn Jensen, a PhD candidate at the University of Victoria. Jensen plans to use Rubin/LSST data for her research on the progenitors of stellar streams and their role in forming the Milky Way. “Using properties of these stars, we can determine information about their origins and what kind of interactions the stream may have experienced. If we find a pearl necklace with a few scattered pearls nearby, we can deduce that something may have come along and broken the string.”

The VRO’s powerful digital camera and its system of filters make this possible. Its ultraviolet filter, in particular, will help make more streams visible. Astronomers can distinguish stellar streams from all other stars by examining the blue-ultraviolet light at the end of the visible spectrum. They’ll have thousands upon thousands of images to work with.

Rubin Observatory at twilight in May 2022. Among the observatory’s many endeavours is the study of dark matter. Credit: Rubin Obs/NSF/AURA

In fact, the VRO will unleash a deluge of astronomical data that scientists and institutions have been preparing to handle. AI and machine learning will play a foundational role in managing all that data, which should contribute to finding even more stellar streams.

“Right now it’s a labor-intensive process to pick out potential streams by eye—Rubin’s large volume of data presents an exciting opportunity to think of new, more automated ways to identify streams.”

Astronomers are still finding more stellar streams. Earlier this month, a paper in The Astrophysical Journal presented the discovery of another one. Researchers found it in Gaia’s Data Release 3. It’s likely associated with the merger of the Sequoia dwarf galaxy.

It seems certain that astronomers will keep finding more stellar streams. Their value as tracers of the Milky Way’s history is considerable. But if scientists can use them to understand the distribution of dark matter on a small scale, they’ll get more than they bargained for.

The post The Milky Way’s History is Written in Streams of Stars appeared first on Universe Today.

Hmmm spaceflight is not the easiest of enterprises. NASA have let us know that their plans for the Mars Sample Return Mission have changed. The original plan was to work with ESA to collect samples from Perseverance and return them to Earth by 2031. Alas like many things, costs were increasing and timescales were slipping and with the budget challenges, NASA has had to rework their plan. Administrator Bill Nelson has now shared a simpler, less expensive and less risk alternative.

The Mars Perseverance Rover departed Earth as part of the Mars 2020 mission on 30 July 2020. It’s no quick nip round the corner to get to the red planet so it arrived just under 7 months later on 18 February 2021. Among its many tasks was to collect rock samples, package them up into tubes and deposit them ready for collection by another future mission to return them to Earth. The samples are to be analysed in Earth based laboratories to help us understand the formation of the Solar System, to look for signs of ancient life on Mars and to enable future human exploration. So far so good but enter NASAs budgetary challenges. 

Illustration of Perseverance on Mars

In response to these budget challenges and to an independent review of the Mars Sample Return mission, NASA have had to get creative. The mission design has been updated to include a simpler, less risky approach and at lower cost. The timescales for the sample return have also now been pushed out to return the samples by 2040 instead of the original target date 9 years earlier. 

The team at NASA are under no illusions as to the complexity of the task at hand. To land safely on Mars is just the beginning. The samples have to be collected and safely stowed away, then the rocket must take off from Mars and return safely to Earth! This has never been done before without human intervention – think Apollo with astronauts bringing several kilograms of lunar samples back for analysis. 

At the time of writing this report, NASA do not yet have a way to reduce the costs yet maintain a high level of confidence of success. NASA has asked multiple teams to work together to come up with a plan that takes an innovative approach with where possible, proven technology. They are to work with other industries on proposals to find ways that the mission can be delivered to the cost challenges, with less complexity and by bringing the delivery of the samples back to the 2030’s. 

Nicky Fox, NASA’s associate administrator from Washington said “NASA does visionary science – and returning diverse, scientifically-relevant samples from Mars is a key priority.” Clearly it’s a challenge, not only the logistics of the mission itself but to bring it in given the constraints facing the team is no mean feat. One thing NASA has on its side is their can-do attitude. It’s an organisation that never fails to impress with ingenious solutions. I have no doubt that, by the end of the 2039 we will see the samples returned to Earth in another first for interplanetary exploration. 

Source : NASA Sets Path to Return Mars Samples, Seeks Innovative Designs

The post The Current Mars Sample Return Mission isn’t Going to Work. NASA is Going Back to the Drawing Board appeared first on Universe Today.

Just like Isaac Newton, Galileo and Albert Einstein, I’m not sure exactly when I became aware of Peter Higgs. He has been one of those names that anyone who has even the slightest interest in science, especially physics, has become aware of at some point. Professor Higgs was catapulted to fame by the concept of the Higgs Boson – or God Particle as it became known. Sadly, this shy yet key player in the world of physics passed away earlier this month.

Peter Higgs was born on 29th May 1929 in Newcastle upon Tyne. He suffered with asthma as a child and, coupled with the family moving around due to his father’s work, was schooled at home for much of his earlier years. Whilst living in Bristol, Higgs’ father had to move to Bedford so Peter and is Mum stayed behind. Eventually he enrolled in Cotham Grammar School in Bristol where he excelled at science and won many prizes for his work. Surprisingly this tended to focus around chemistry rather than physics. It was at Cotham that he became fascinated by quantum mechanics.

By the time he was 17, he had moved to City of London School and here he focussed on mathematics, eventually graduating with a first-class honours degree in physics. His masters came two years later in 1952. In 1954, he was awarded a PhD with a thesis titled ‘Some Problems in the Theory of Molecular Vibrations from the Universe.’ Higgs tried to get a job at Kings College where he earned his PhD but was unsuccessful so moved to the University of Edinburgh and set about answering the question – Why do some particles have mass?

He worked upon the idea that, at the time when the Universe began, particles did not have mass. This was later gained due to interactions with something which became known as the Higgs Field. The concept was a field that permeates through space giving mass to sub-atomic particles like quarks and leptons. His work was an evolution of earlier work from Yoichiro Nambu from the University of Chicago.

Two other groups of scientists published work at similar times with a similar concept, but Higgs’ work published in 1964 was prominent and so the (theoretical) particle, that transferred mass, became known as the Higgs Boson. In the years that followed, scientists hunted for the new particle, chiefly using the Large Hadron Collider at CERN but Higgs retired by 2006 with nothing detected.

The Hadron Collider is a particle accelerator that had been built to simulate conditions equivalent to billionths of a second after the Big Bang. By crashing subatomic particles together and observing the interactions, scientists can probe the very nature of matter. It cost $10bn and it was this that scientists hoped would prove, or otherwise Higgs’ theory.

In 2012, Higgs received word from CERN at the collider ‘Peter should come to the CERN event or he will regret it!’ Higgs went along and to his delight and amazement, and at the age of 83 and 48 years after he published his theory, he heard that the Higgs Boson had finally been discovered. Higgs later said “It’s been a long wait but it might have been even longer, I might not have been still around. At the beginning I had no idea whether a discovery would be made in my lifetime.”

The discovery changed the face of physics and it was this that led to being awarded a Nobel Prize. Higgs didn’t own a mobile phone though and he found out about his award when a neighbour stopped him in the street to congratulate him. It is clear though that Higgs was in it for the science and not the fame that came with his groundbreaking discovery. He was a man who was often referred to as shy and retiring and he will be a great loss to the world of Physics. Professor Higgs died on 8th April 2021.

The post Peter Higgs Dies at 94 appeared first on Universe Today.

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.

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

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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.

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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

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In 2011, astronomers with the Wide Angle Search for Planets (WASP) consortium detected a gas giant orbiting very close to a Sun-like (G-type) star about 700 light-years away. This planet is known as WASP-39b (aka. “Bocaprins”), one of many “hot Jupiters” discovered in recent decades that orbits its star at a distance of less than 5% the distance between the Earth and the Sun (0.05 AU). In 2022, shortly after the James Webb Space Telescope (JWST) it became the first exoplanet to have carbon dioxide and sulfur dioxide detected in its atmosphere.

Alas, researchers have not constrained all of WASP-39b’s crucial details (particularly its size) based on the planet’s light curves, as observed by Webb. which is holding up more precise data analyses. In a new study led by the Max Planck Institute for Solar System Research (MPS), an international team has shown a way to overcome this obstacle. They argue that considering a parent star’s magnetic field, the true size of an exoplanet in orbit can be determined. These findings are likely to significantly impact the rapidly expanding field of exoplanet study and characterization.

The study was led by Dr. Nadiia M. Kostogryz and her fellow researchers from the MPS. They were joined by astronomers and astrophysicists from the Center for Astronomy (Heidelberg University), the Astrophysics Group at Keele University, the Kavli Institute for Astrophysics and Space Research at the Massachusetts Institute of Technology (MIT), and the Space Telescope Science Institute (STScI). The paper describing their research, “Magnetic origin of the discrepancy between stellar limb-darkening models and observations,” was recently published in Nature Astronomy.

The “hot Jupiter” exoplanet WASP-69b orbits its star so closely that its atmosphere is being blown into space. Credit: Adam Makarenko/W. M. Keck Observatory

A light curve is the measurement of a star’s brightness over longer periods. Using the Transit Method (Transit Photometry), astronomers monitor stars for periodic dips in brightness, which can result from an exoplanet passing (transiting) in front of their face relative to the observer. In addition to being the most widely used method for detecting exoplanets, precise observations of light curves allow astronomers to estimate the size and orbital period of the exoplanets.

These curves can also reveal information about the composition of the planet’s atmosphere based on light passing through its atmosphere as it makes a transit – a technique known as “transit spectroscopy.” Unfortunately, estimates on planet size suffer from an observational issue known as “limb darkening.” Dr. Kostogryz explained in an MPS press statement:

“The problems arising when interpreting the data from WASP-39b are well known from many other exoplanets – regardless [of] whether they are observed with Kepler, TESS, James Webb, or the future PLATO spacecraft. As with other stars orbited by exoplanets, the observed light curve of WASP-39 is flatter than previous models can explain.”

The edge of the stellar disk (or “limb”) plays a decisive role in interpreting a star’s light curve. Since the limb corresponds to the star’s outer (and cooler) layers, it appears darker to the observer than the inner area. However, the star does not actually shine less brightly further out. This “limb darkening” affects the shape of the exoplanet signal in the light curve, as the dimming determines how steeply the curve falls during a planetary transit and then rises again. Historically, astronomers have not been able to reproduce observational data using conventional stellar models accurately.

In every case, the decrease in the star’s brightness was less abrupt than model calculations predicted. Clearly, something was missing from the models that prevented astronomers from reproducing exoplanet transit signals. As Dr. Kostogryz and her team discovered, the missing piece is stellar magnetic fields, which are generated by the motion of conductive plasma inside a star. The team first noticed this when examining selected light curves obtained by NASA’s Kepler Space Telescope between 2009 and 2018.

An illustration of Earth’s magnetic field. Credit: ESA/ATG medialab

The researchers also proved that the discrepancy between observational data and model calculations disappears if the star’s magnetic field is included in the computations. To this end, the team turned to selected data from NASA’s Kepler Space Telescope, which captured the light of thousands and thousands of stars from 2009 to 2018. To this end, they modeled the atmosphere of typical Kepler stars in the presence of a magnetic field and then simulated observational data based on these calculations. When they compared their results to real data, they found it accurately reproduced Kepler’s observations.

They also found that the strength of the magnetic field can have a profound effect, where limb darkening is more pronounced in stars with weak magnetic fields and less in stars with strong ones. Lastly, they extended their simulations to emission spectra data obtained by the JWST and found that the magnetic field of the parent star influences limb darkening differently at different wavelengths. These findings will help inform future exoplanet studies, leading to more precise estimates of the planets’ characteristics. Said Dr. Alexander Shapiro, coauthor of the current study and head of an ERC-funded research group at the MPS:

“In the past decades and years, the way to move forward in exoplanet research was to improve the hardware, the space telescopes designed to search for and characterize new worlds. The James Webb Space Telescope has pushed this development to new limits. The next step is now to improve and refine the models to interpret this excellent data.”

The researchers now plan to extend their analyses to stars different from the Sun, which could lead to refined estimates of exoplanet mass for rocky planets (similar to Earth). In addition, their findings indicate that the light curves of stars could be used to constrain the strength of stellar magnetic fields, another characteristic that is challenging to measure.

Further Reading: MPS, Nature Astronomy

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