In this Tokyo cafe, the waiters are robots operated remotely by people with disabilities

A pop-up restaurant in Tokyo has run a trial employing disabled people to work as waiting staff. But this is no ordinary trial. Instead of taking orders or clearing tables themselves, the staff of the Dawn ver.β cafe were piloting a team of robots from the comfort of their homes.

The robots were developed by Kentaro “Ory” Yoshifuji, CEO of the Ory Lab, which he set up with co-founders, Aki Yuki and Yoshifumi Shiiba. The remote-controlled OriHime-D robots are part of on an ongoing project to use technology to combat social isolation. They stand 1.2 metres tall and have expressionless, white faces reminiscent of Japanese Noh masks. They transmit video and audio back to their controllers, who are able to direct them from home via a smartphone or tablet.

The cafe is named after a similar establishment in a 2008 anime called Time of Eve, where robots and humans co-exist as equals. The addition of ver.β (beta) to the cafe’s name was there to show it was a work in progress – a beta version.

Five OriHime-D robots were used during the trial, and they were controlled by a team of 10 people, with a range of conditions including amyotrophic lateral sclerosis (ALS), the most common motor-neuron disease. They were all paid 1000 yen ($8) per hour, which is just above the minimum wage in Japan.

Even people with very limited mobility are able to interact with and control OriHime-D robots. Ory Labs has created a video showing how a man who is only able to move his eyes can still operate the robot, and another where a man in a hospital bed gets an OriHime-D to hand a cup of coffee to a waiting Yoshifuji.

Yoshifuji has an impressive track record as an inventor with an interest in using technology for good. Between the ages of 10 and 14 he did not attend school due to poor health and went on to represent Japan in the 2005 Intel Science and Engineering Fair (ISEF), with a project designed to help wheelchairs climb curbs. It was the years he spent missing out on school that ultimately led to the development of OriHime, which he sees as a way to help people overcome adversity and disability to actively participate in society through the use of avatars.

There are 75 million people in the world who need a wheelchair but only 5% to 15% of those in need actually have access to one. Globally, there are an estimated 200 million visually impaired people and 466 million people with hearing loss who aren’t able to access help. But in recent years, the topic of assistive technology has started to attract more attention.

While there are still many accessibility barriers technology can be used to break down, the use of robots is already underway in some situations. The Shin-tomi nursing home in Tokyo has around 20 different robots in use performing different aspects of residents’ care, from leading exercise sessions to powering interactive soft toys.

Voyager 2 has reached interstellar space

NASA’s Voyager 2 has become the second human-made object in history to reach the edge of our solar system, after the spacecraft exited the protective bubble of particles and magnetic fields created by the Sun.

Its twin, Voyager 1, crossed this boundary in 2012, but Voyager 2 — launched 41 years ago — carries a working instrument that will provide first-of-its-kind observations of the nature of this gateway into interstellar space.

Voyager 2 now is slightly more than 18 billion kilometres from Earth. While the probes have left the heliosphere, Voyager 1 and Voyager 2 have not yet left the solar system, and won’t be leaving anytime soon.

Mission operators still can communicate with Voyager 2 as it enters this new phase of its journey, but information — moving at the speed of light — takes about 16.5 hours to travel from the spacecraft to Earth. By comparison, light travelling from the Sun takes about eight minutes to reach Earth.

NASA also is preparing an additional mission — the upcoming Interstellar Mapping and Acceleration Probe (IMAP), due to launch in 2024 — to capitalise on the Voyagers’ observations. Voyager 2 launched in 1977, 16 days before Voyager 1, and both have travelled well beyond their original destinations. The spacecraft were built to last five years and conduct close-up studies of Jupiter and Saturn.

However, as the mission continued, additional flybys of the two outermost giant planets, Uranus and Neptune, proved possible.

Helmholtz & his revolutionary Ophthalmoscope

Dec. 6, 1850 - Hermann von Helmholtz demonstrated his revolutionary ophthalmoscope to the Berlin Physical Society.

Ophthalmoscopy, also called funduscopy, is a test that allows a health professional to see inside the fundus of the eye and other structures using an ophthalmoscope (or funduscope). It is done as part of an eye examination and may be done as part of a routine physical examination. It is crucial in determining the health of the retina, optic disc, and vitreous humor.

History

Although some credit the invention of the ophthalmoscope to Charles Babbage in 1847, it was not until it was independently reinvented by Hermann von Helmholtz that its usefulness was recognized - it was to revolutionize ophthalmology.

Hermann von Helmholtz

While training in France, Andreas Anagnostakis, an ophthalmologist from Greece, came up with the idea of making the instrument hand-held by adding a concave mirror. Austin Barnett created a model for Anagnostakis, which he used in his practice and subsequently when presented at the first Ophthalmological Conference in Brussels in 1857, the instrument became very popular among ophthalmologists.

In 1915, Francis A. Welch and William Noah Allyn invented the world's first hand-held direct illuminating ophthalmoscope, precursor to the device now used by clinicians around the world. This refinement and updating of von Helmholtz's invention enabled ophthalmoscopy to become one of the most ubiquitous medical screening techniques in the world today. The company Welch Allyn started as a result of this invention.

Medical Use

Ophthalmoscopy is done as part of a routine physical or complete eye examination. It is used to detect and evaluate symptoms of various retinal vascular diseases or eye diseases such as glaucoma.

In patients with headaches, the finding of swollen optic discs, or papilledema, on ophthalmoscopy is a key sign, as this indicates raised intracranial pressure (ICP) which could be due to hydrocephalus, benign intracranial hypertension or brain tumor, amongst other conditions. Cupped optic discs are seen in glaucoma.

In patients with diabetes mellitus, regular ophthalmoscopic eye examinations are important to screen for diabetic retinopathy as visual loss due to diabetes can be prevented by retinal laser treatment if retinopathy is spotted early.

In arterial hypertension, hypertensive changes of the retina closely mimic those in the brain, and may predict cerebrovascular accidents (strokes).

Etymology

The word ophthalmoscopy uses combining forms of ophthalmo- + -scopy, yielding "viewing the eye". The word funduscopy derives from fundus + -scopy, yielding "viewing the far inside".

Scientists have successfully created a fifth state of matter in space

In 1995, researchers were able to prove that a fifth state of matter — the Bose-Einstein condensate — could be created at very low temperatures. Until recently, this state of aggregation could only be generated using high-vacuum apparatus on Earth and was the state was extremely short-lived due to gravity. However, a German research team has now succeeded in generating and studying the Bose-Einstein condensate using an unmanned space rocket.

In addition to the standard aggregate states of solid, liquid, and gas, matter can also have other states. A gas, for example, can be ionised at high temperatures to form a plasma.

In 1995, researchers were able to prove that a fifth state of matter could be created at very low temperatures — the Bose-Einstein condensate.

In quantum mechanics, the Bose-Einstein condensate is used to conduct quantum experiments. For example, it can be used to study gravitational waves or the Earth's gravitational field. Until now, however, this special state of aggregation could only be generated using high-vacuum apparatus on Earth and the state was extremely short-lived due to gravity. A German research team has now succeeded for the first time in generating and studying the Bose-Einstein condensate on board an unmanned space rocket. The duration of experiments is limited by gravity.

The formation of such a condensate at extremely low temperatures was first predicted by the two physicists Satyendranath Bose and Albert Einstein. Researchers detected the Bose-Einstein condensate after cooling atoms to a temperature only one millionth of a degree above absolute zero (0 Kelvin).

As the atoms are cooled, the movement of atoms decreases and, at the same time, the wavelength of the particles increases. Near absolute zero, an almost complete standstill is reached and the wave functions (each particle is described in quantum mechanics with its own wave function) of the individual particles overlap. In this state, all atoms in the system have the same physical properties — they behave like a single atom or a superatom.

Although experiments with Bose-Einstein condensates are extremely useful, they have so far proved difficult to carry out: due to the gravitational forces acting on the atoms in the condensate cloud, they fall down in a very short time and experiments can't continue.

In order to be able to study the cold condensate cloud for longer, researchers therefore use very high drop towers. In this way, the duration of the experiments can be extended.

But even very tall drop towers such as the 122-metre tower in Bremen, you can only achieve free-fall in weightlessness for a few seconds — or as we call it, microgravity," explained Maike Lachmann from the University of Hanover in World of Physics. "In space, on the other hand, much longer and more precise measurements can be made".

In order to conduct experiments with Bose-Einstein condensates in space, researchers developed a chip made of rubidium atoms and, in January 2017, transported it aboard space rocket MAIUS-1 from Esrange Space Center.

Once in space, the temperature of the atoms was reduced by laser and evaporative cooling until the condensate formed. The researchers were then able to investigate how the atomic gas behaved when manipulated in different ways. During its boost phase and six-minute space flight, 110 experiments were performed.

In 2020 and 2021, further experiments will be carried out, including experiments with potassium atoms. Researchers from the German Aerospace Center (DLR) and NASA will use the findings of the German researchers in future for their own research on cold quantum gases aboard the ISS.

Source - Business Insider Deutschland

The Kilogram Is Dead. Meet the Kilogram 2.0

The NIST's replica of Le Grand K (front), the international weight that defines a kilogram which is stored in a vault in France. Physical objects will be replaced by Planck's constant as the definition of a kilogram.

For nearly 150 years, the official weight of a kilogram was determined by a shiny cylinder of platinum locked away in a French vault.

The kilogram, like the metre and the second, is one of the seven fundamental units of measurement (also known as the International System of Units or the metric system, the "SI" for short). These were first formalized in the 1875 Treaty of the Metre. Back then, the best way to agree on the weight of a kilogram was to forge a single hunk of metal and call it "Le Grand K." And for more than a century, all scientific scales were calibrated back to that one physical reference point (with copies stored in a dozen countries).

But even solid objects can change over time. When Le Grand K was weighed in the 1980s, it was a couple of micrograms lighter, meaning that all highly accurate scientific scales had to be recalibrated. That's what nerds call a real pain in the mass.

Luckily, teams of metrologists were already on the case (metrology is the science of weights and measures), searching for a universal constant that would generate a fixed value for the kilogram that's true now and a million years from now.

They had already found such a physics fix for the second, which was redefined in 1967 from 1/86,400th of a day to something much more confusing, but constant. It takes 9,192,631,770 oscillations of a special microwave beam to excite atoms of the isotope caesium-133 to a higher energy level. Since that number will never change (unlike the exact length of a day), that's your new second!

Same for the metre. Instead of being defined as the length of a single, meter-long metal pole forged back in 1889, it was redefined in 1983 as the distance light travels in a vacuum in 1/299,792,458th of a second.

It wasn't until 2017 that scientists working at the U.S. National Institute of Standards and Technology (NIST) and similar bodies worldwide finally agreed on a universal constant for the kilogram. The achievement required solving one of the thorniest physics problems of the last century, coming up with a numerical value for Planck's constant.

Without getting too technical, physicist Max Planck proved in 1900 that matter releases energy in discrete chunks called "quanta." His equation for measuring those packets of energy included a constant called h, hitherto known as Planck's constant. Thanks to Einstein, we know that energy and mass are mathematically related, so physicists figured out that Planck's constant (which is a fixed unit of energy) could yield the world's most accurate measurement of mass.

Calculating the exact value of Planck's constant took decades and some serious technological innovation (specifically a nifty device called a Kibble Balance), but now even distracted kindergarteners know that Planck's constant is 6.626070150 × 10^(-34) kg⋅m2/s.

In mid-November, at the annual meeting of the International Bureau of Weights and Measures (BIPM) in Versailles, France, representatives from more than 60 countries voted to approve a new and everlasting definition of the kilogram as calculated by the Planck constant. No more hunk of metal — the kilogram's mass is now tied to Planck's constant. New definitions were also announced for SI units the ampere (electrical current), the kelvin (temperature) and the mole (number of molecules or atoms in an element). These new definitions will take effect on May 20, 2019.

The original platinum kilogram prototype will remain in that underground French vault, while countless generations of scientists make life-changing discoveries using the kilogram 2.0.

Source - EarthSky.org

Why does a full moon look full?

Remember that half the moon is always illuminated by the sun. That lighted half is the moon’s day side.

Technically speaking, the moon is full at the instant it’s 180 degrees from the sun in ecliptic longitude. So why does a full moon look full? Remember that half the moon is always illuminated by the sun. That lighted half is the moon’s day side.

In order to appear full to us on Earth, we have to see the entire day side of the moon. That happens only when the moon is opposite the sun in our sky. So a full moon looks full because it’s opposite the sun.

That’s also why every full moon rises in the east around sunset – climbs highest up for the night midway between sunset and sunrise (around midnight) – and sets around sunrise. Stand outside tonight around sunset and look for the moon. Sun going down while the moon is coming up? That’s a full moon, or close to one.

Just be aware that the moon will look full for at least a couple of night around the instant of full moon.

A full moon is opposite the sun. We see all of its dayside.

If a full moon is opposite the sun, why doesn’t Earth’s shadow fall on the moon at every full moon? The reason is that the moon’s orbit is titled by 5.1 degrees with respect to Earth’s orbit around the sun. At every full moon, Earth’s shadow sweeps near the moon. But, in most months, there’s no eclipse.

A full moon normally passes above or below Earth’s shadow, with no eclipse.

Source - EarthSky.org

14 fascinating physics facts about flakes (of snow)

Every snowflake is a unique marvel of physics, thermodynamics, chemistry, and pure natural beauty. Try to remember that next time you’re shoveling the driveway.

Source - Perimeter Institute

Oct. 30, 1958 - Medical Oops Leads to First Coronary Angiogram

In the basement laboratory of the Cleveland Clinic, US, a cardiologist accidentally injects a large amount of dye into the small vessels of a patient's heart during a routine imaging test. To the doctor's great surprise — and relief — the dye doesn't send the heart into a fatal spasm, and this happy accident marks the birth of modern cardiac imaging.

Before F. Mason Sones Jr. made his fateful mistake, conventional medical wisdom held that injecting contrast dye into the coronary arteries — the small vessels feeding the heart itself — would instantly cause a deadly arrhythmia called ventricular fibrillation. Although doctors in the 1950s regularly used dye to view the valves and chambers of a person's heart, fear of killing their patients kept them from even attempting to visualize the smaller vessels.

Without a clear view of the coronary arteries, cardiologists couldn't assess a person's heart attack risk or intervene if the vessels were partially or completely blocked. But as soon as Sones discovered that dye could be safely inserted into the coronary arteries, he began developing the technique of modern angiography, which lets cardiologists see and fix clogged arteries in the heart.

Sones' accident marked a huge step forward for cardiac imaging, but the event itself was far from serene. On the morning of Oct. 30 when the incident occurred, Sones was attempting to look at the heart valves of a 26-year-old man with rheumatoid arthritis. The procedure required injecting 40 to 50 milliliters of contrast dye into the patient's aorta, a giant vessel that sits right next to the opening of the right coronary artery.

To Sones' horror, right before an assistant injected the dye, the tip of the tube flipped into the right coronary artery, and more than half the dye went squirting into the tiny vessel. According to an account from cardiologist Julio Sosa, who was present at the time, Sones cried, "We've killed him!" and rushed to the patient's side to get ready to open his chest and massage the heart by hand if necessary.

But instead of going into ventricular fibrillation, the patient's heart simply skipped a few beats and then recovered. Sones realized almost immediately that he had made a very important discovery: Patients could easily survive even a large injection of dye into their heart vessels.

"During the ensuing days I began to think that this accident might point the way for the development of a technique which was exactly what we had been seeking," Sones wrote. "If a human could tolerate such a massive injection of contrast directly into a coronary artery, then it might be possible to accomplish this kind of opacification with smaller amounts of a more dilute contrast. With considerable fear and trepidation we embarked on a program to accomplish this objective."

Over the next few years, Sones and colleagues at the Cleveland Clinic developed the technique of cardiac catheterization, which involved inserting a flexible tube into the coronary arteries, injecting a small amount of dye and viewing the arteries with an X-ray camera. By 1967, Sones had performed this procedure on more than 8,200 patients, and today he is known as the father of modern cardiac imaging.

Dr. Mason Sones Jr.

"Without the work of Dr. Mason Sones, Jr. — the most important contributor to modern cardiology — all our efforts in myocardial revascularization would have been fruitless," said pioneering cardiac surgeon René Favaloro. Favaloro was the first doctor to perform coronary bypass surgery, a procedure that shunts blood around a clogged coronary artery.

Cardiac imaging is thought to have saved the lives of countless heart patients during the last 50 years. Perhaps most of those saved owe their lives to a serendipitous medical error in 1958.

Sources -

1. Wikipedia

2. Wired

3. Pacific Science Center

Short Story of the Long S

October 28 or 29, 1675 – Gottfried Wilhelm von Leibniz (a German polymath who discovered the field of calculus independently) makes the first use of the long s (∫) as a symbol of the integral in calculus.

The long, medial, or descending s (ſ) is an archaic form of the lower case letter s. It replaced a single s, or the first in a double s, at the beginning or in the middle of a word (e.g. "ſucceſsſul" for "successful"), and in ligature form (e.g. "Tiſſick" for "Tissick"). The modern letter form is known as the short, terminal, or round s.

The medial 's' in Old Roman cursive

The long s was derived from the old Roman cursive medial s. When the distinction between majuscule (uppercase) and minuscule (lowercase) letter forms became established, toward the end of the eighth century, it developed a more vertical form. During this period, it was occasionally used at the end of a word, a practice that quickly died but that was occasionally revived in Italian printing between about 1465 and 1480. The double s in the middle of a word was also written with a long s and a short s, as in Miſsiſsippi.

Title page of John Milton's Paradise Lost, featuring an "ſt" ligature

The long s survives in elongated form, with an italic-styled curled descender, as the integral symbol ∫ used in calculus; Leibniz based the character on the Latin summa "sum", which he wrote ſumma. This use first appeared publicly in his paper De Geometria, published in Acta Eruditorum of June 1686, but he had been using it in private manuscripts at least since 28 October 1675.

Source - Wikipedia

Hubble telescope fixed by 'jiggling it around'

The Hubble space telescope is close to resuming full operations after Nasa “jiggled it around”.

The telescope was sidelined earlier this month after a gyroscope failed, leaving it unable to point in the right direction during observations. The device had been expected to fail at some point this year, but the surprise came when a backup did not kick in properly after the initial failure. As a result, Hubble has remained in so-called safe mode and all science observations are on hold.

Gyroscopes are needed to keep Hubble pointing in the right direction as it operates 545km above Earth. Precise pointing is crucial: astronomers use the telescope to peer deep into the cosmos, revealing faraway galaxies, black holes and solar systems. Last week, astronomers said they may have discovered the first moon outside our solar system, with Hubble’s help.

The problem with the backup gyroscope was spotted when detectors in the gyroscope wrongly signalled that the wheel within the device was rotating at a much greater rate than that 19,200 revolutions per minute it should be spinning at.

Nasa expected Hubble to return to normal science operations soon after it performed a “running restart” of the gyroscope on 16 October, which turned the device off for a second. The intention was to clear any faults that may have occurred during a restart on 6 October. That did not seem to work so it was followed up on 18 October with a series of spacecraft manoeuvres – known as turns – in an attempt to clear any blockage around the sealed “float” which contains the spinning wheel in the gyroscope.

At the same time the system was switched between two modes to help with the procedure. Nasa believes that the dodgy rotation speeds could have arisen if the float was off centre in the device. Further jiggling of the telescope and twiddling of switches was performed: the issue now appears to be resolved.

The 28-year-old telescope has had trouble with its gyroscopes before. Shuttle astronauts replaced all six in 2009 during a spacewalk on the final servicing mission. Three of the devices are now considered unusable.

Source - The Guardian

Jonas Salk, Polio Vaccination and Elvis Presley - a strange connection!

He was more than just the King of Rock and Roll. Elvis Presley popularised polio vaccination in the United States during the 1950s and is credited with raising immunisation levels in the United States from 0.6% to over 80% in just six months.

The American Polio Epidemic and the Salk Polio Vaccine

Poliomyelitis or polio is an infectious disease caused by the polio virus. Regular instance of polio epidemic ravaged North American cities from 1930s to 1950s with thousands of cases and thousands of death.

Fear of polio became widespread in the US, and the local governments would shutdown public places and lock down their cities during instances of polio outbreaks. But none of those lock downs or disinfection worked. Polio continued to infect and affect Americans, especially the children.

The National Foundation for Infantile Paralysis, in 1948, asked medical researcher and virologist Jonas Salk to join their growing network of polio researchers. Salk announced his discovery of an effective polio vaccine in 1955.

Jonas Edward Salk

How Elvis Presley popularised Polio Vaccination

The discovery of the Salk polio vaccine was a major milestone in polio research. It provided a solution to eradicate the epidemic through immunisation. But the American public was not readily receptive of the concept of immunisation. Public health officials and the American government had a hard time convincing the people to receive the polio vaccine.

Several organisations had also opposed immunisation and other emerging healthcare initiatives. They also used the fact that Salk was a Jew and the use of his vaccine was an anti-Christian effort aimed at contaminating the bodies of children.

The National Foundation for Infantile Paralysis, in 1956, launched communication strategies that revolved around television, radio, and print publicity to promote polio vaccination. One of the strategies employed by the foundation together with the New York City Health Department was to use celebrities. In October 1956, the two institutions launched a publicity stunt with the help of the young Elvis Presley.

On 28 October 1956, Elvis Presley got a polio vaccination on national television. Other press people covered the event and newspapers across the U.S. published the resulting photographs. The stunt indicated that the vaccine was safe, thus helping promote public confidence. This single event is credited with raising immunisation levels in the United States from 0.6% to over 80% in just six months.

It is believed that Elvis Presley and the teenagers who rallied behind the Salk polio vaccine might be the first, largest, and most successful example of teen health activism.

Sources -

1. The Guardian

2. Wikipedia

3. Version Daily

Which Ocean Is the World’s Smallest?

We humans may spend most of our time on land, but we live in a saltwater-dominated world, with ocean covering 71 percent of Earth's surface. Geographers divide the globe's ocean into named regions, and the smallest of these is the Arctic Ocean.

Even the smallest of the world's oceans is impressively vast. Stretching for about 13.8 million square kilometres, the Arctic Ocean measures over 4 times larger than the size of India. It's located at the polar region of the Northern Hemisphere and is almost completely surrounded by the continents of Europe, Asia and North America. Frigid conditions keep the Arctic Ocean partly covered in ice throughout the year and entirely covered in winter, although rising global temperatures have led to increased melting of this Arctic sea ice.

The Arctic Ocean is not only ranked the smallest in size (it's 10 times smaller than the Pacific Ocean), it's also the shallowest. The average ocean depth is 3.7 kilometres. The Arctic Ocean's average depth, meanwhile, is much shallower — around 1.04 kilometres. That's like water sloshing in a kiddie pool when compared to the deepest regions of the Pacific Ocean, which have been measured to around 11 kilometres deep.

The relatively small size and depth of the Arctic Ocean have led some to resist classifying it as an ocean, instead referring to it as part of the Atlantic Ocean called the Arctic Mediterranean Sea or simply the Arctic Sea. Seas are considered smaller parts of oceans that are partially enclosed by land.

It may seem unusual that some scientists would challenge whether a body of water is an ocean, but debate around the world's oceans extends beyond the Arctic. Historically, the global community has recognised four oceans: the Atlantic, Pacific, Indian and Arctic Oceans.

In 2000, the International Hydrographic Organization (IHO), added a fifth: The Southern Ocean. This ocean, also called The Antarctic Ocean, encircles Antarctica and makes up the southernmost waters on Earth, below the 60-degree south latitude. The addition of the Southern Ocean, while generally accepted, has not yet been ratified because not all members of the IHO have officially accepted the parameters defining the Southern Ocean as a fifth ocean.

So how many oceans are there — four or five? For now, the surest answer may be one since, technically, all the world's oceans are in fact connected as a single, vast body of salt water.

Source - HowStuffWorks.com

William Lassell - brewer turned astronomer and his discoveries

Oct. 24, 1851 - William Lassell discovered two moons of Uranus, Umbriel and Ariel.

William Lassell was an English merchant and made his fortune as a beer brewer, which enabled him to indulge his interest in astronomy.

He built an observatory at his house "Starfield" in West Derby, a suburb of Liverpool. There he had a 24-inch (610 mm) reflector telescope, for which he pioneered the use of an equatorial mount for easy tracking of objects as the Earth rotates. He ground and polished the mirror himself, using equipment he constructed.

In 1846 Lassell discovered Triton, the largest moon of Neptune, just 17 days after the discovery of Neptune itself by German astronomer Johann Gottfried Galle. In 1848 he independently co-discovered Hyperion, a moon of Saturn. In 1851 he discovered Ariel and Umbriel, two moons of Uranus.

In 1850, Lassell made his first sighting of the dark inner ring of Saturn (called the crepe ring); he spent the entire night verifying the discovery only to find in his morning newspaper an article announcing William Bond’s discovery of the same phenomenon.

Umbriel is a moon of Uranus and consists mainly of ice with a substantial fraction of rock, and may be differentiated into a rocky core and an icy mantle

Ariel is the fourth-largest of the 27 known moons of Uranus

The crater Lassell on the Moon, a crater on Mars, the asteroid 2636 Lassell and a ring of Neptune are named in his honour. At the University of Liverpool the William Lassell prize is awarded to the student with the highest grades graduating the B.Sc. program in Physics with Astronomy each year.

Sources -

1. Encyclopædia Britannica
2. Journal for the History of Astronomy
3. Wikipedia
4. Pacific Science Center

Chinese city 'plans to launch artificial moon to replace streetlights'

In Chengdu, there is reportedly an ambitious plan afoot for replacing the city’s streetlights: boosting the glow of the real moon with that of a more powerful fake one.

Jiutian Tower illuminated at night with full moon in the background, Chengdu, China

The south-western Chinese city plans to launch an illumination satellite in 2020. According to an account in the People’s Daily, the artificial moon is “designed to complement the moon at night”, though it would be eight times as bright. The “dusk-like glow” of the satellite would be able to light an area with a diameter of 10-80km, while the precise illumination range could be controlled within tens of metres – enabling it to replace streetlights.

The vision was shared by Wu Chunfeng, the chairman of the private space contractor Chengdu Aerospace Science and Technology Microelectronics System Research Institute Co (Casc). Wu reportedly said testing had begun on the satellite years ago and the technology had now evolved enough to allow for launch in 2020.

The People’s Daily report credited the idea to “a French artist, who imagined hanging a necklace made of mirrors above the Earth which could reflect sunshine through the streets of Paris all year round”.

The likelihood of Chengdu’s fake moon rising remains to be seen. But there are precedents for this moonage daydream rooted in science, though the technology and ambitions differ.

In 2013 three large computer-controlled mirrors were installed above the Norwegian town of Rjukan to track the movement of the sun and reflect its rays down on the town square. (Read more at Rjukan sun: the Norwegian town that does it with mirrors)

Longer ago, in the 1990s, a team of Russian astronomers and engineers succeeded in launching a satellite into space to deflect sunlight back to Earth, briefly illuminating the night-time hemisphere. The Znamya experiment was to “test the feasibility of illuminating points on Earth with light equivalent to that of several full moons”, the New York Times said. “Several” proved an overstatement, but the design was shown to be sound. (Read more at Russians to Test Space Mirror as Giant Night Light for Earth)

A more ambitious attempt, Znamya 2.5, was made in 1999, prompting preemptive concerns about light pollution disrupting nocturnal animals and astronomical observation. But Znamya 2.5 misfired on launch and its creators failed to raise funding for another attempt.

The People’s Daily was quick to reassure those concerned about the fake moon’s impact on night-time wildlife. Kang Weimin, director of the Institute of Optics, School of Aerospace, Harbin Institute of Technology, explains that, "the light of the satellite is similar to a dusk-like glow, so it should not affect animals’ routines”.

Let's wait and see..

Source - The Guardian