Archaeology News Online

A team from the University of Kentucky’s Department of Physics and Astronomy has observed evidence of ancient impacts that are thought to have shaped and structured our Milky Way galaxy. Using observations from the Sloan Digital Sky Survey (SDSS) telescope, the team analyzed the spatial distribution  of 3.6 million stars and found ripples that support evidence of the Milky Way’s ancient impacts  [Credit: University of Kentucky] Deborah Ferguson, a 2016 UK graduate, is the lead author on a paper that published this week in the Astrophysical Journal . Ferguson conducted the research as an undergraduate student with co-authors Susan Gardner, a professor of physics and astronomy in the UK College of Arts and Sciences, and Brian Yanny, a staff scientist and astrophysicist in the Fermilab Center for Particle Astrophysics. Their paper, "Milky Way Tomography with K and M Dwarf Stars: the Vertical Structure of the Galactic Disk," presents observational evidence of asymmetric ripples i...

The origin and nature of Mars is mysterious. It has geologically distinct hemispheres, with smooth lowlands in the north and cratered, high-elevation terrain in the south. The red planet also has two small oddly-shaped oblong moons and a composition that sets it apart from that of the Earth. A colossal impact with a large asteroid early in Mars' history may have ripped off a chunk of the northern hemisphere  and left behind a legacy of metallic elements in the planet's interior. The crash also created a ring of rocky  debris around Mars that may have later clumped together to form its moons, Phobos and Deimos  [Credit: University of Colorado at Boulder] New research by University of Colorado Boulder professor Stephen Mojzsis outlines a likely cause for these mysterious features of Mars: a colossal impact with a large asteroid early in the planet's history. This asteroid -- about the size of Ceres, one of the largest asteroids in the Solar System -- smashed into Mars, ripp...

One night three months ago, Rosa Castro finished her dinner, opened her laptop, and uncovered a novel object that was neither planet nor star. Therapist by day and amateur astronomer by night, Castro joined the NASA-funded Backyard Worlds: Planet 9 citizen science project when it began in February -- not knowing she would become one of four volunteers to help identify the project's first brown dwarf, formally known as WISEA J110125.95+540052.8. This illustration shows the average brown dwarf is much smaller than our sun and low mass stars and only slightly  larger than the planet Jupiter [Credit: NASA's Goddard Space Flight Center] After devoting hours to skimming online, publicly available "flipbooks" containing time-lapse images, she spotted a moving object unlike any other. The search process involves fixating on countless colorful dots, she explained. When an object is different, it simply stands out. Castro, who describes herself as extremely detail oriented, has...

A simulated universe created by Swinburne University of Technology and The University of Melbourne has revealed galaxies emerging in the first billion years after the Big Bang were experiencing a recession. The density of gas in and around a simulated galaxy just over a billion years after the Big Bang. New gas  is arriving at too great a rate for the galaxy to convert it into stars and the gas piles up  [Credit: Swinburne University of Technology] It has long been imagined that the first galaxies formed after the Big Bang were rapidly growing, turning huge clouds of pristine gas into stars at rates thousands of times greater than what we see in the Milky Way today. However, new modelling inspired by economics theory has instead revealed the galaxies weren’t forming as fast as they could have. Swinburne astronomer Associate Professor Alan Duffy created supercomputer simulations of the early Universe treating the complex forming galaxies as a simple economical model with raw ma...

In July 2015, NASA’s New Horizons spacecraft sent home the first close-up pictures of Pluto and its moons – amazing imagery that inspired many to wonder what a flight over the distant worlds’ icy terrain might be like. Wonder no more. Using actual New Horizons data and digital elevation models of Pluto and its largest moon Charon, mission scientists have created flyover movies that offer spectacular new perspectives of the many unusual features that were discovered and which have reshaped our views of the Pluto system – from a vantage point even closer than the spacecraft itself. Pluto flyover [Credit: NASA/JHUAPL/SwRI/Paul Schenk and John Blackwell, Lunar and Planetary Institute] This dramatic Pluto flyover begins over the highlands to the southwest of the great expanse of nitrogen ice plain informally named Sputnik Planitia. The viewer first passes over the western margin of Sputnik, where it borders the dark, cratered terrain of Cthulhu Macula, with the blocky mountain ranges locate...

Scientists have long held the belief that planets – including Earth – were built from rocky asteroids, but new research challenges that view. These images show temperature maps as simulated by MAGHNUM as a result of mud convection, in a medium sized asteroid (above) and a large asteroid (below). Temperatures are shown in degrees Celcius  [Credit: Planetary Science Institute] Published in Science Advances , a journal of the American Association for the Advancement of Science, the research suggests that many of the original planetary building blocks in our solar system may actually have started life, not as rocky asteroids, but as gigantic balls of warm mud. Phil Bland, Curtin University planetary scientist, undertook the research to try and get a better insight into how smaller planets, the precursors to the larger terrestrial planets we know today, may have come about. Planetary Science Institute Senior Scientist Bryan Travis is a co-author on the paper “Giant convecting mud balls ...

How does the gas in the centre of the Milky Way behave? Researchers from Heidelberg University, in collaboration with colleagues from the University of Oxford, recently investigated the motion of gas clouds in a comprehensive computer simulation. The new model finally makes it possible to conclusively explain this complex gas motion. Astrophysicists Dr Mattia C. Sormani (Heidelberg) and Matthew Ridley (Oxford) conducted the research, on Heidelberg's part, at the Collaborative Research Centre "The Milky Way System" (CRC 881). Spiral galaxy Messier 61, picture taken with the Hubble Space Telescope. Our Milky Way might look like this galaxy  [Credit: ESA/Hubble & NASA. Acknowledgements: G. Chapdelaine, L. Limatola, and R. Gendler] Our solar system is located in the outer regions of the Milky Way, a disk-shaped galaxy with an approximate diameter of 100,000 light years. From Earth, its appearance can only be observed indirectly, by measuring positions and movements of sta...

A team of astronomers from the Inter University Centre for Astronomy & Astrophysics (IUCAA), and Indian Institute of Science Education and Research (IISER), both in Pune, India, and members of two other Indian universities, have identified a previously unknown, extremely large supercluster of galaxies located in the direction of constellation Pisces. This is one of the largest known structures in the nearby Universe, and is at a distance of 4,000 million (400 crore) light-years away from us. Fig1 : The distribution of galaxies, from Sloan Digital Sky Survey (SDSS), in and around Saraswati supercluster. It is  clearly visible that the density of galaxies is very high in the center region of the image, that is the Saraswati supercluster  region. The typical size of a galaxy here is around 250,000 light years. The galaxy sizes are increased for representation [Credit: IUCAA] This novel discovery is being published in the latest issue of The Astrophysical Journal , the premier...

Discovered by British astronomer William Herschel over 200 years ago, NGC 2500 lies about 30 million light-years away in the northern constellation of Lynx. As this NASA/ESA Hubble Space Telescope image shows, NGC 2500 is a particular kind of spiral galaxy known as a barred spiral, its wispy arms swirling out from a bright, elongated core. NGC 2500 [Credit: ESA/Hubble/NASA] Barred spirals are actually more common than was once thought. Around two-thirds of all spiral galaxies -- including the Milky Way -- exhibit these straight bars cutting through their centers. These cosmic structures act as glowing nurseries for newborn stars, and funnel material towards the active core of a galaxy. NGC 2500 is still actively forming new stars, although this process appears to be occurring very unevenly. The upper half of the galaxy -- where the spiral arms are slightly better defined -- hosts many more star-forming regions than the lower half, as indicated by the bright, dotted islands of light. Th...

The dichotomy concerns the so-called angular momentum (per unit mass), that in physics is a measure of size and rotation velocity. Spiral galaxies are found to be strongly rotating, with an angular momentum higher by a factor of about 5 than ellipticals. What is the origin of such a difference? Spiral galaxies are found to be strongly rotating, with an angular momentum higher by a factor of about 5 than ellipticals.  What is the origin of such a difference? [Credit: WikiCommons] An international research team investigated the issue in a study just published in the Astrophysical Journal . The team was led by SISSA Ph.D. student JingJing Shi under the supervision of Prof. Andrea Lapi and Luigi Danese, and in collaboration with Prof. Huiyuan Wang from USTC (Hefei) and Dr. Claudia Mancuso from IRA-INAF (Bologna). The researchers inferred from observations the amount of gas fallen into the central region of a developing galaxy, where most of the star formation takes places. The ou...

A dried-out river valley with numerous tributaries is seen in this recent view of the Red Planet captured by ESA’s Mars Express. Libya Montes colour view [Credit: ESA/DLR/FU Berlin] This section of the Libya Montes region, which sits on the equator at the boundary of the southern highlands and northern lowlands, was imaged on 21 February 2017 by the spacecraft’s high-resolution stereo camera. The Libya Montes highlands mountains, one of the oldest regions on Mars, were uplifted during the formation of the 1200 km-wide Isidis impact basin some 3.9 billion years ago, seen at the north of the context map. Libya Montes in context [Credit: ESA/DLR/FU Berlin] The features seen across the broader region indicate both flowing rivers and standing bodies of water such as lakes or even seas that were present in the early history of Mars. The prominent river channel that runs from south to north (left to right in the main colour image) is thought to have cut through the region around 3.6 billion y...

Two separate teams of scientists have identified major challenges for the development of life in what has recently become one of the most famous exoplanet systems, TRAPPIST-1. Two separate teams of scientists from the CfA have identified major challenges for the development of life  in TRAPPIST-1. The TRAPPIST-1 system, depicted here in an artist's conception, contains seven roughly  Earth-sized planets orbiting a red dwarf, which is a faint, low-mass star. This star spins rapidly and generates  energetic flares of ultraviolet radiation and a strong wind of particles. The research teams say the behavior  of this red dwarf makes it much less likely than generally thought that the three planets orbiting well within  the habitable zone could support life [Credit: NASA/JPL-Caltech/R. Hurt] The teams, both led by researchers at the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Mass., say the behavior of the star in the TRAPPIST-1 system makes it muc...

In the context of space, the term 'cloud' can mean something rather different from the fluffy white collections of water in the sky or a way to store data or process information. Giant molecular clouds are vast cosmic objects, composed primarily of hydrogen molecules and helium atoms, where new stars and planets are born. These clouds can contain more mass than a million suns, and stretch across hundreds of light years. Composite image of W51 [Credit: X-ray: NASA/CXC/PSU/L.Townsley et al; Infrared: NASA/JPL-Caltech] The giant molecular cloud known as W51 is one of the closest to Earth at a distance of about 17,000 light years. Because of its relative proximity, W51 provides astronomers with an excellent opportunity to study how stars are forming in our Milky Way galaxy. A new composite image of W51 shows the high-energy output from this stellar nursery, where X-rays from Chandra are colored blue. In about 20 hours of Chandra exposure time, over 600 young stars were detected as ...

Last year, the existence of an unknown planet in our Solar system was announced. However, this hypothesis was subsequently called into question as biases in the observational data were detected. Now Spanish astronomers have used a novel technique to analyse the orbits of the so-called extreme trans-Neptunian objects and, once again, they point out that there is something perturbing them: a planet located at a distance between 300 to 400 times the Earth-Sun separation. Will another planet be added to the list of Mercury, Venus, Earth, Mars, Jupiter, Saturn,  Uranus and Neptune in our Solar System? [Credit: NASA] Scientists continue to argue about the existence of a ninth planet within our Solar System. At the beginning of 2016, researchers from the California Institute of Technology (Caltech, USA) announced that they had evidence of the existence of this object, located at an average distance of 700 AU or astronomical units (700 times the Earth-Sun separation) and with a mass ten ti...

An assistant professor in New Mexico State University's College of Arts and Sciences' Astronomy Department recently coauthored a paper detailing the shape and motions of stars within a distant galaxy. Acting as a natural telescope in space, the gravity of the extremely massive foreground galaxy cluster MACS J2129-0741  magnifies, brightens, and distorts the far-distant background galaxy MACS2129-1, shown in the top box [Credit: NASA,  ESA, STScI, and Sune Toft (Dark Cosmology Centre at the Niels Bohr Inst., Univ. of Copenhagen)] Moire Prescott's contribution to the research was published in the scientific research journal Nature . "My contribution was taking the speed of the stars versus position in the galaxy, then using a dynamical model to figure out the most likely velocity and orientation of the galaxy," Prescott said. The galaxy, MACS2129-1, is described as a dead-disk galaxy, Prescott said. "A dead-disk galaxy is a galaxy that's both disk-shaped bu...

According to Einstein's theory of General Relativity when a ray of light passes close to a very massive object, the gravity of the object attracts the photons and deviates them from their intial path. This phenomenon, known as gravitational lensing, is comparable to that produced by lenses on light rays, and acts as a sort of magnifier, changing the size and intensity of the apparent image of the original object. The multiple images of the discovered galaxy are indicated by white arrows (bottom right shows the scale  of the image in seconds of arc) [Credit: Hubble Space Telescope (HST)] Using this effect, a team of scientists from the Instituto de Astrofisica de Canarias (IAC) led by researcher Anastasio Díaz-Sánches of the Polytechnic University of Cartagena (UPT) has discovered a very distant galaxy, some 10 thousand million light years away, about a thousand times brighter than the Milky Way. It is the brightest of the submillimetre galaxies, called this because of their very st...