Posted on by Evan Gough

The Milky Way’s History is Written in Streams of Stars

This artist’s impression shows a myriad of stellar streams in and around the Milky Way. These stretched-out remnants of dwarf galaxies and star clusters showcase gravitational interactions between stars, clumps of dark matter, and the entire galaxy. Rubin Observatory will reveal many more stellar streams than we have seen thus far, enabling scientists to study our galaxy’s history and properties of dark matter in more detail than ever before. Image Credit: NOIRLab

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.

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Posted on by Mark Thompson

The Current Mars Sample Return Mission isn’t Going to Work. NASA is Going Back to the Drawing Board

Mars Sample Return mission

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.

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Posted on by Mark Thompson

Peter Higgs Dies at 94

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. Read More 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.

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.

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Posted on by Carolyn Collins Petersen

More Views of the 2024 Eclipse, from the Moon and Earth Orbit

NASA's LROC view of the total solar eclipse shadow centered over Cape Girardeau, Missouri. Courtesy: NASA/GSFC/Arizona State University.
NASA's LROC view of the total solar eclipse shadow centered over Cape Girardeau, Missouri. Courtesy: NASA/GSFC/Arizona State University.

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.

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Posted on by Mark Thompson

Baby Stars Discharge “Sneezes” of Gas and Dust

The baby star at the center surrounded by a bright disk called a protostellar disk. Spikes of magnetic flux, gas, and dust in blue. Researchers found that the protostellar disk will expel magnetic flux, gas, and dust—much like a sneeze—during a star's formation.

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. 

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Posted on by Alan Boyle

How Did Pluto Get Its Heart? Scientists Suggest an Answer

New Horizons view of Pluto
The heart-shaped region of Pluto's surface was formed at least in part by a cataclysmic "splat," scientists say. (Credit: NASA / JHUAPL / SwRI)

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.

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Posted on by Mark Thompson

The Milky Way’s Role in Ancient Egyptian Mythology

the sky goddess Nut, covered in stars, is held aloft by her father, Shu, and is arched over Geb, her brother the Earth god. On the left, the rising sun (the falcon-headed god Re) sails up Nut’s legs. On the right, the setting sun sails down her arms towards the outstretched arms of Osiris, who will regenerate the sun in the netherworld during the night.

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! 

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Posted on by Matt Williams

You Can't Know the True Size of an Exoplanet Without Knowing its Star's Magnetic Field

Artist's impression of a "hot Jupiter" orbiting close to a Sun-like star. Credit: NASA

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.

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Posted on by Matt Williams

Stellar Winds Coming From Other Stars Measured for the First Time

Infrared image of the shockwave created by the massive giant star Zeta Ophiuchi in an interstellar dust cloud. Credit: NASA/JPL-Caltech; NASA and The Hubble Heritage Team (STScI/AURA); C. R. O'Dell, Vanderbilt University

An international research team led by the University of Vienna has made a major breakthrough. In a study recently published in Nature Astronomy, they describe how they conducted the first direct measurements of stellar wind in three Sun-like star systems. Using X-ray emission data obtained by the ESA’s X-ray Multi-Mirror-Newton (XMM-Newton) of these stars’ “astrospheres,” they measured the mass loss rate of these stars via stellar winds. The study of how stars and planets co-evolve could assist in the search for life while also helping astronomers predict the future evolution of our Solar System.

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Posted on by Brian Koberlein

Neutron Stars Could be Heating Up From Dark Matter Annihilation

Artist’s impression of the magnetar in the star cluster Westerlund 1. Credit: ESO/L. Calçada

One of the big mysteries about dark matter particles is whether they interact with each other. We still don’t know the exact nature of what dark matter is. Some models argue that dark matter only interacts gravitationally, but many more posit that dark matter particles can collide with each other, clump together, and even decay into particles we can see. If that’s the case, then objects with particularly strong gravitational fields such as black holes, neutron stars, and white dwarfs might capture and concentrate dark matter. This could in turn affect how these objects appear. As a case in point, a recent study looks at the interplay between dark matter and neutron stars.

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