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Close Cassini flybys of Saturn’s ring moons Pan, Daphnis, Atlas, Pandora, and Epimetheus

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Saturn’s ring moons Pan, Daphnis, Atlas, Pandora, and Epimetheus

New findings have revealed that five tiny moons snuggled in and near Saturn’s rings. The closest-ever flybys by NASA’s Cassini spacecraft disclose that the surfaces of these unusual moons are covered with material from the planet’s rings and from the icy particles emrging out of Saturn’s larger moon Enceladus. This research succesfully draws a picture of the competing processes shaping these tiny-moons.

The daring, close flybys of these odd little moons let us find how they interact with Saturn’s rings,” said Bonnie Buratti of NASA’s Jet Propulsion Laboratory in Pasadena, California, who led a team of 35 co-authors that published their work in the journal Science on March 28. One of a Pakistani Planetory scientists Dr. Nozair Khawaja was among these co-authors.

The new research carried out from data gathered by six of Cassini’s instruments before its mission ended in 2017, is a strong vindiction that dust and ice from the rings accretes onto the moons embedded within and near the rings.

Scientists also found that the moon surfaces are highly porous, further verified that they were formed in multiple stages as ring material settled onto denser cores that might be remnants of a larger object that broke apart. The porosity also helps explain their shape: Rather than being spherical, they are blobby and ravioli-like, with material stuck around their equators.

Image. JPL NASA

The process may be going on throughout the rings, and the largest ring particles are also accreting ring material around them. Detailed analysis of these tiny ring moons may further provide us more about the charactrastics of the ring particles themselves.

Of the satellites studied, the surfaces of those closest to Saturn — Daphnis and Pan — are the most altered by ring materials. The surfaces of the moons Atlas, Prometheus and Pandora, farther out from Saturn, have ring material as well — but they’re also coated with the bright icy particles and water vapor from the plume spraying out of Enceladus. (A broad outer ring of Saturn, known as the E ring, is formed by the icy material that fans out from Enceladus’ plume.)

Scientist got the main data set from Cassini’s Visible and Infrared Mapping Spectrometer (VIMS), which gathered light visible to the human eye and also infrared light of longer wavelengths. It was the first time Cassini was close enough to create a spectral map of the surface of the innermost moon Pan. By analyzing the spectra, VIMS was able to learn about the composition of materials on all five moons.

VIMS observed that the ring moons closest to Saturn look the reddest, similar to the color of the main rings. Though Scientists are not fully aware with the exact composition of the material that appears red, but they hold on it is likely a mixture of organics and iron. The moons just outside the main rings, on the other hand, appear more blue, similar to the light from Enceladus’ icy plumes.

The six uber-close flybys of the ring moons, completed between December 2016 and April 2017, involved all of Cassini’s optical remote sensing instruments that study the electromagnetic spectrum. They worked alongside the instruments that examined the dust, plasma and magnetic fields and how those elements interact with the moons.

Resaerchers are craving to come across that what triggered the moons to form? For finding a reasoable answwr scientists will use the new data to model scenarios and could apply the insights to small moons around other planets and possibly even to asteroids.

Katie Bouman: The woman behind first black hole image

Katie Bouman

This week millions of science enthusiasts across the globe gazed at the image of one of the most extraordinary and mysterious things in the universe, the black hole which was previously considered to be
non-observable. The woman who made this historical feat possible is just 29 years old. Katie Bouman, a computer scientist at Massachusetts Institute of Technology (MIT), led the development of an algorithm which proved to be critical in the image development of a supermassive black hole some 55 million light years away from earth. Katie Bouman instantly got recognition across the internet and applauds for her contribution to this historical milestone.  

The recently released image of a super massive black hole

Katie Bouman, a Ph.D. student at MIT, started working on the algorithm nearly three years ago when she was in her graduate studies while leading the project and assisted by teams from MIT’s Computer Science and Artificial Laboratory, MIT Haystack Observatory and Harvard-
Smithsonian Center for Astrophysics. Due to the extremely high gravitational pull of a black hole, nothing, not even light, can escape from. Although, Einstein’s theory of General relativity predict their presence in the universe. Since then no single telescope was powerful enough to capture a black hole, a network of telescopes spread all over the world, collected the data simultaneously on hundreds of hard drives. Dr. Bouman’s method was crucial for the transformation of enormous data into an image through the multiple algorithms she spearheaded. The results of the algorithms were then analyzed by different teams to provide a credibility to the findings.

Editorial: A journey to inspire, innovate and discover

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Humanity’s quest to explore the cosmos is as old as the history of civilization. The principles of rocket science can be traced back to more than two thousand years. The first rocketeers did not know much about the scientific underpinnings of rockets, they learned by doing, often failing. Through their discoveries they laid the foundation for modern rocketry.

Rocket development dates back to somewhere “between 428 to 347 BC” when Archytus, a Greek philosopher, mathematician, and astronomer, reported having constructed and flown the first self-propelled, small bird-shaped flying device. The ‘bird’ was suspended by wire or mounted at the end of a bar that revolved around a pivot. Using a jet of steam, Archytus, was able to propel the bird through the air; in effect he demonstrated the concept of reactive propulsion.

Over 500 years later, between 65 and 125 AD, another Greek inventor, known as Hero of Alexandria, developed the first known device to use steam for propulsion, called ‘Hero engine’. It consisted of a hollow sphere placed on top of a vessel of heated water. Around the same time, the Chinese developed a simple form of gunpowder, prepared with saltpeter, sulfur and charcoal dust, which when ignited, produced colorful sparks and smoke. They used these fireworks for religious and social festivals. Soon they started experimenting by filling bamboo tubes with gunpowder and noticed that if one end of the bamboo tube was tightly sealed with clay and ignited, the fireworks escaped from the other end, producing an upward thrust that led to the invention of the first solid rocket. However, they were unaware that this could be used for destructive purposes or even for travelling into space, from this point forward the use of rockets spread to India and Europe.

Meanwhile, in the 13th century, Roger Bacon, an English monk, worked and improved the formula for gunpowder so that it could result in more explosive power. He wrote down his insights in manuscripts that became a part of a growing body of knowledge on rocketry. By the 16th century, the chemistry and mechanics of rockets were becoming well-known and military manuals included chapters on designing and building rockets.

 Later on,Kazimierz Siemienowicz a commander in the Polish Royal Artillery studied rocket design; one of his manuscript included a design for a multistage rocket, consisting of two or more stages, each of which contained its own engines and propellant. The staging became a critical technology for rockets designed for space. The 16th and 17th centuries were significant because of incredible advancements in astronomy, chemistry, physics, and mathematics and the great contributors to these advancements were Galileo and Newton.

 Galileo investigated the effect of gravity on falling bodies and summarized that all bodies fall at a uniform rate of acceleration assuming there is no air resistance, while Isaac Newton turned out to be a game changer in rocketry and his three laws of motion lay down the solid foundation for rocket development, his first law of motion which stated, “A body will persist to do whatever it happens to be doing unless it is acted upon by a force”, was key in these developments. However, even with Newton’s scientific underpinnings, no further fundamental advancements were made in the manufacture of rockets until Colonel William Congreve, who developed a standard set of rockets and made the greatest impact by standardizing their parts and manufacturing techniques.

The 19th century is remembered as significant for scientific evolution and rocket science reached new heights during the same time. Robert H Goddard regarded as the “father of modern rocketry”. Although his basic concept of liquid-fueled rocket got validation a few years after his death, actually it was Goddard who launched his prototype space rocket in 1926 for the first time in history. He and his team launched around 34 rockets between 1926 to 1941 through private sources. Due to Goddard’s efforts Yuri Gagarin carried out the first manned flight into space on 12th April 1961.

In 2011 the United Nations General assembly marked 12th April as the International Day of Human Space Flight. Since then, it is celebrated across the globe to pay homage to the thousands of individuals whose contributions turned an ancient dream into a reality.

YURI GAGARIN: The First Man in space

The stars and heavens have always been fascinating humankind. Ancient hunter groups relied on celestial objects during the long journeys for the right direction and seasonal changes. In the early 15th century, Galileo Galilei was the first man who looked into the majestic cosmos through an optical telescope. But it would take another four hundred years until the man would able to travel into space, when on April 12th 1961, Yuri Gagarin, a Soviet fighter-pilot-turned Cosmonaut, became the first man in space. It was an unprecedented feat and the 108 minutes orbit of the Soviet Union’s spacecraft Vostok, some 327 kilometers above the earth, was the first of many odysseys to explore the vastness of cosmos.

Yuri Alekseyevich Gagarin was born on a farm near a small village a few hundred miles from Moscow. His father was a carpenter. He got his education from the local school and later studied at vocational and technical schools. In his teen, he witnessed a Soviet fighter plane make an emergency landing near his village, this incident had a profound impact on young Yuri. Years later, when he got a chance to join a flying club, he eagerly accepted the offer and glided a solo flight in 1955.

It was a time of intense rivalry between the USA and USSR to surpass each other and maintain global dominance in every field of science and technology including space exploration. The Soviet Space program was more advanced than the United States with the successful launching of the first artificial satellite, Sputnik in 1957. In the midst of this space race, 27 years old senior lieutenant submitted his application and was amongst the 200 Soviet fighter pilots selected. The selected candidates had a vast experience of flying high accelerating vehicles under the influence of intense centripetal, centrifugal and gravitational forces.

Soviets Union sent a couple of test flights before the final plunge and used a prototype of Vostok Spacecraft, on board was a life-sized dummy named Ivan Ivanovic and a dog named Zvezdochka.

Young Gagrin

On April 12, 1961, at 09:07 A.M Moscow time, the Vostok spacecraft first time blasted off into space with an unprecedented speed of more than 17,500 miles per hour or 5 miles per second. The spacecraft broke free of the Earth’s gravitational pull and entered orbit around the planet, orbiting once before re-entering the atmosphere and landing back on Soviet soil.

Since then, none had a physical experience of how weightlessness felt like and how it would impact the pilot, Vostok had little controls onboard. It either controlled from the ground or worked automatically. In case of an emergency, Gagarin supposed to receive override codes that would allow him to control the capsule manually. But Sergei Korolev, Chief Designer of the Soviet space program, disregarded protocol and proides these code to the pilot prior to the flight. Unlike modern spacecraft, it was a spherically shaped capsule to maintain the center of gravity for its one-man-crew, no matter what the spacecraft’s orientation was. The spacecraft 10 days’ worth of supplies in case the engines failed and Gagarin had to wait for the orbit to naturally die.

The Vostok capsule had to slow down its speed by means of a retrorocket for reentry into the earth’s atmosphere. The capsule accelerated at the speeds ranging from 500 mph to 225 m/s. During the free fall under the earth’s gravitational force, Gagarin experienced a tremendous gravitational pull that was eight times to the pull of Earth’s gravity. Fortunately, he was still able to maintain his conscience.

The mission was being monitored by the Fédération Aéronautique Internationale (FAI), the governing body for aerospace records. According to its rules, the mission could only be counted as an official spaceflight if the pilot landed with the spacecraft but Gagarin parachuted from 4 km above the surface. His ejection kept as a secret by the Soviet authorities until 1971. Nonetheless, Gagarin still remembered as the first man to go into space and orbit around the planet earth.   

After the flight, Gagarin instantly became a global hero. He welcomed by a cheering crowd of hundreds and thousands of Russians at Red Square in Moscow. Later on, he traveled across the world and became a symbol of Soviet supremacy in space. He was made Deputy of the Supreme Soviet Council (the highest legislative body in the Soviet Union) and was appointed the commander of the Cosmonauts’ Detachment. Gagarin had become a prominent figure and portrayed a soft image of the Soviet Union. They did not want to risk losing such a popular public figure and therefore were hesitant about allowing Gagarin to return to space. Gagarin, however, was allowed to make test flights of fighter jets for Air Force.

International Day of Human Space Flight

Unfortunately, on March 27, 1968, Gagarin along with another pilot killed while on a test-flight of jet fighter aircraft, MiG-15. He survived by his wife, Valentina Ivanovna Goryacheva, and two daughters. When in 1969, NASA’s Apollo 11, the first manned mission to the moon landed, its crew left behind a commemorative medallion bearing Gagarin’s name to honor him.

Gagarin’s achievement still got celebrated . Russian cosmonauts participate in a number of pre-launch traditions before way up to the Soyuz spacecraft ― such as urinating on the launch bus tires and following in the footsteps of Great Gagarin. Every year on 12th April, the space community across the world commemorates Gagarin’s achievement, a part of this is “Yuri’s night” that founded in 2001 in honor of the great legend and attracts thousands of space enthusiasts every year.

Scientists reveal the first-ever direct image of Black Hole

first-ever direct image of  a Black hole
first-ever direct image of a Black Hole

Scientists reveal the first-ever direct image of one of the most mysterious things in the universe, the black hole, which was previously unseen and considered to be non-observable. The supermassive black hole seen in the image released is a halo of dust and gas tracing the outline of the accretion discs of the monster body in the core of Messier 87 galaxy, some 55 million light years away from the earth. The black hole itself–a trapdoor from which nothing and absolutely nothing can escape– it is considered that black hole cannot be seen and only the shadowy edges of hot swirling clouds of gas, destined to be sucked in by the monster, are visible.

The breakthrough image unveil by a team of more than 200 scientists working on the Event Horizon Telescope (EHT), a network of eight radio telescopes spread from locations in Spain, Chile, Antarctica and other parts of the world. These images will bring revolution in our understanding of one of the most mysterious things in the universe.


The massive swirling clouds of dust and gas are rotating around the black hole at the speeds nearly approaching to that of light. The crescent-shaped appearance of the swirling disc is because the particles in the side of the disc are thrown towards earth faster and appear bright. The dark shadow within the disc is the “event horizon”― a point of singularity. Beyond this singularity point, there is no escape from the enormous gravitational pull of the supermassive black hole from which even the light cannot escape.
The research is also important because it tests the Einstein’s “theory of general relativity” which had predicted the presence of these massive sinkholes out there in the grand cosmos.

A Japanese spacecraft, Hayabusa-2 blasts the surface of asteroid Ryugu

Japanese spacecraft, Hayabusa-2

A Japanese spacecraft, Hayabusa-2, successfully blasts the surface of an asteroid named Ryugu, creating an artificial crater on the small world’s surface which scientists hope to snag. Japan’s space agency, JAXA, reported that the projectile, a two-kilogram copper cylinder, separated from the Hayabusa-2 spacecraft along with a camera known as DCAM3 to record this
“Small Carry-on Impactor” (SCI) operation. Hayabusa-2 flew to the far side of the Asteroid 162173 Ryugu, simply called Ryugu, to retreat from the debris that would be ejected when the projectile hit. “This is the world’s first collision experiment with an asteroid!” JAXA tweeted after the successful blast.

Japanese spacecraft, Hayabusa-2 released photographs


Hayabusa-2 was launched in 2014 and has been studying the 900 meters wide asteroid Ryugu up close since last June. The mission plan includes a touchdown of the spacecraft inside the crater to pick up a pinch of dust samples of the asteroid. In February this year, Hayabusa-2 had touched down on the asteroid’s surface and successfully collected the samples. But the second upcoming touchdown onto the asteroid, preceded by the latest blast on the surface will provide scientists with samples of subsurface dust which has not been exposed to sunlight or other space radiations for billions of years. Scientists hope to additional knowledge about the origin of inner planets, in particular the origin of water and organic compounds on earth, all relevant to the origin of life on earth.

The methane gas episodically wafts into the Mars’ atmosphere near the Martian equator.

A team of scientists working with the European Space Agency’s (ESA) Mars Express Orbiter has reported that methane gas episodically wafts into the Mars’ atmosphere within Gale crater, a 96-mile-wide crater near the Martian equator.

Mars Twin Rover

This notion once considered perplexing and bewildering is now widely accepted by scientists because NASA’s Curiosity Rover also measured a marked increase in methane gas around the same crater in 2013. However, quite mysteriously, the methane levels decreased within two months which was bewildering as according to the calculations, it would take a few hundred years for Martian atmosphere to breakdown methane molecules.

Mars methane mystery


Scientists are not sure if both, periodic increases and then subsequent decreases, are due to geological or biological processes. Two theories have been used to explain these findings: it might have been created by a geological process known as serpentinization, which requires both heat and liquid water. Or it could be a product of life — specifically methanogens, microbes that release methane as a waste product. Methanogens thrive in places lacking oxygen, such as rocks deep underground and the digestive tracts of animals.

Possible methane sources


The Mars Express findings also point to a possible source of the methane, about 300 miles east of Gale. In that region, ice must exist just below the surface. Dr. Giuranna, principal investigator for the Mars Express instrument that made the measurements, said: “methane could be released
episodically along faults that break through the permafrost due to partial melting of ice”. The findings are especially important as they can help direct future missions and serve as prime locations to search for signs of life.

India joined an elite club of countries with anti-satellite (ASAT) capabilities

India joined an elite club of countries with anti-satellite (ASAT) capabilities after ― USA, Russia, and China ― when it successfully destroyed one of its old satellite from a missile launched from the Abdul Kalam Island off the eastern coast of India. The March 27 test by India was not it’s first but a second attempt after a failed test on February 12, 2019. ASAT technology launches a missile from the surface which tracks and targets a satellite and destroys it with through collision.

GRAPHIC-INDIA-ANTI-SATELLITE-MISSILE

The capability can not only be used to neutralize old or useless satellites but can also be used to target satellites of any adversary, in case of a conflict, thereby crippling enemies’ missile and radar systems. However, the debris created by such a test remains in the earth’s orbit for days or even years (one-third of the debris in the space was created after China’s anti-satellite test in 2007) and poses a threat to hundreds of other satellites in earth’s orbit as well astronauts working on the International Space Station (ISS).

Different stages of anti satellite missile

NASA said that it had identified 400 pieces of orbital debris from that one event and the risk of small debris impacting ISS is above 44% over a period of 10 days. Jim Bridenstine, the NASA administrator, said: “that is a terrible terrible thing to create an event that sends debris in an apogee that goes above the international space station.” He also said that “We are charged with enabling more activities in space than we’ve ever seen before for the purpose of benefiting the human condition”. Referring to various experi-ments and research being done on ISS, he said “whether it’s pharmaceuticalss or printing human organs in 3-D to save lives here on Earth, or manufacturing capabilities in space that you’re not able to do in a gravity well, all of those are placed at risk when these kinds of events happen”

NASA’s 3-D Printed Habitat Challenge

Top three teams, competing in the latest level of NASA’s “3-D Printed Habitat Challenge”, have been awarded a share of $100,000.
Team SEArch+/Apis Corn, who won the first prize in the software modeling, presented a unique shaped habitat which is structurally designed to reinforce itself continuously and allows light to enter through trough-shaped ports on the sides and top. Zopherous won the second price and their design would be autonomously built by a roving printer.

3D-Printing

The roving printer would construct habitat one at a time and then move to the next site. Mars incubators came up with a model consisting of four volumes separated into functional zones which will provide a safe and robust environment for human life on earth.

3D-printed-habitat-challenge

The teams also made short interactive videos providing detailed insights into their designs and 3-D miniature models to showcase the interiors. The 3D-Printed Habitat Challenge is a competition to create sustainable shelters suitable for the Moon, Mars or beyond using resources available on-site in these locations. The multi-level 3D-Printed Habitat Challenge puts teams to the test in several areas of 3D-printing, including modeling software, material development, and construction. In addition to aiding human space exploration, technologies sought from this competition could also lead to lower-cost housing solutions on Earth and other benefits.

zopherus-exterior-NASA-3D Printing


The latest level ― Complete Virtual Construction ― is one of the multi-level competition comprised of three phases and was started in 2015 by NASA in a partnership with NASA’s Centennial Challenges program and Bradley University.

Science fest: Imperial College London, held fifth annual science competition

Zinc air power team, presenting its idea
Zinc air power team, presenting its idea

Imperial College London, held fifth annual science competition. The competition invited pupils from secondary schools and for the first time was open to international students. Out of a total of 150 participating teams, from across the globe, seven were chosen to showcase their projects at Imperial College in front of live audience and panel of judges.

The Science steins team
The Science steins team


The competition aims to encourage and motivate young students through fun activities involving the solution of global problems. The competition’s aims were aligned with four of the Sustainable Development Goals (SDGs) of the United Nations ― affordable and clean energy, good health, clean water, and sanitation.

Dr Jess Wade trying out the piezo electric plate
Dr Jess Wade trying out the piezo electric plate


The winning team from Pui Ching Middle School, Macau, presented the idea of Zinc-air batteries, powered from reacting zinc and oxygen. These are not only rechargeable but also have low cost, safe and environment-friendly. But the reaction was carried out in the presence of platinum and palladium which are rare and expensive elements. The team has, therefore, replaced platinum and palladium with Metal-Organic Framework (MOF), a crystalline material composed of a 3D network of metal ions.

ICL Fringe March 2018 | Photo by Owen Billcliffe Photography
ICL Fringe March 2018 | Photo by Owen Billcliffe Photography

Sciencesteins, the runner up team, presented an idea for treatment of polluted water through nanorobots―tiny machines designed to perform a specific task at nano-dimensions. Another team, The Handy-Capable, worked on the challenge of clean and affordable energy: their idea was to place the piezoelectric plates (plates made from materials which accum-ulate electric charge in response to certain mechanical stress) before and after ticket barriers at train stations to power London streetlights.

The winners and runners up won trophies while all participants were given certificates and a Schools Science Competition mug.

The winners and runners up won trophies while all participants were given certificates and a Schools Science Competition mug.