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Radio waves

Beijing blocks radio signals during Communist Party centenary

Chinese authorities are to impose control over radio signals as the 100th anniversary of the ruling Chinese Communist Party (CCP) approaches on July 1.

The new measures prohibit radio stations or remotely controlled radio equipment from transmitting or transmitting radio waves, and block specific frequencies from 12:00 p.m. to 12:00 p.m. on July 1, except those approved for daytime broadcast activities. same, according to a document released by Beijing. authorities on June 20.

Authorities must ban the use of intercoms, wireless microphones and outdoor base stations for wireless networks in the Second Ring Road that surrounds central Beijing.

Other types of equipment using radio waves, such as remote control car models and GPS jammers, are also on the ban list, which was established with the Central Theater Command of the Chinese regime’s army.

Flying objects such as doves, drones, kites and balloons have been banned from flying over nine parts of the city since June 13.

Additionally, on June 20, Beijing Capital International Airport reminded passengers entering Beijing that inspections will be stepped up, suggesting reducing carry-on baggage and preparing an extra hour to two hours for check-in.

The railways department ordered a second inspection for people entering the capital. Likewise, packages sent to Beijing are only allowed after a double security check.

The petitioners, who hope their grievances can be rectified by central authorities, have reportedly had their movement in the capital restricted or have been arrested at security checkpoints at local train stations.

People who reside in Beijing are also monitored. A video provided to The Epoch Times in early June shows that six guards were assigned to a bus with devices that monitor passenger movements.

As the centenary approached, outspoken dissidents and activists were warned, forced to travel, or disappeared before June 4. Citizens with spiritual beliefs, such as Falun Gong practitioners, have been harassed, arrested, or detained. Even staunch supporters of Mao Zedong, the first leader of the CCP, were also targeted.


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Radio waves

It is the largest radio telescope in the world

It is the largest radio telescope in the world

The world’s largest radio telescope, FAST, is a huge engineering marvel. It measures 500 meters in diameter and was built in the southern province of Guizhou in China. Construction took five years and $ 180 million.

According to researchers via state media, FAST will search for gravitational waves, will detect radio broadcasts from stars and galaxies, and it will also listen for signs of intelligent alien life.

“The ultimate goal of FAST is to discover the laws of the development of the universe,” Qian Lei, one of the associate researchers of the National Astronomical Observatories of the Chinese Academy of Sciences, told public broadcaster CCTV.

More than 8,000 people were moved from their homes in eight villages because the telescope needed radio silence within a five-kilometer radius. According to CCTV, in a recent test, the telescope received radio signals from a pulsar located 1,351 light years from Earth.

The complex project was not without its challenges – it has a radical design and initially struggled to attract staff, in part due to its remoteness. But the benefits of science will be immense. FAST will collect radio waves from an area twice the size of the next largest satellite dish telescope, the Arecibo Observatory in Puerto Rico.

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The massive size of the Chinese observatory means it can detect whisperings of extremely weak radio waves from an array of sources across the Universe, such as the spinning nuclei of dead stars, called pulsars, and hydrogen in distant galaxies. He will also explore a frontier in radio astronomy – using radio waves to locate exoplanets, which may harbor alien life.

Since testing began in 2016, only Chinese scientists have been able to carry out projects studying preliminary data from the telescope. But now, the observation time will be accessible to researchers around the world, said Zhiqiang Shen, director of the Shanghai Astronomical Observatory and co-chair of the FAST oversight committee of the Chinese Academy of Sciences.

The 1.2 billion yuan ($ 171 million) telescope, also known as the Tianyan or “the eye of the sky”, took half a decade to build in the remote Dawodang Depression in the United States. Guizhou province in southwest China. Its 500-meter-wide dish is made up of approximately 4,400 individual aluminum panels that more than 2,000 mechanical winches tilt and maneuver to focus on different areas of the sky. Although it sees less of the sky than some other advanced radio telescopes and has a lower resolution than multi-antenna arrays, FAST’s size makes it particularly sensitive.

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FAST only examines a tiny fraction of the sky at a time, making it unlikely that many new FRBs will be discovered, which are ephemeral and occur in seemingly random locations. But the telescope’s “impressive sensitivity” will be useful for tracking sources in detail, says Laura Spitler, an astronomer at the Max Planck Institute for Radio Astronomy in Bonn, Germany. Repeated observations could allow scientists to learn about the environment from which an FRB emerged and determine whether explosions vary in energy or recur in a defined pattern.

FAST will also spur the efforts of an international collaboration that tries to spot ripples in space-time as they sweep the Galaxy, McLaughlin said. The International Pulsar Timing Array uses radio telescopes around the world to monitor regular pulsar emissions, looking for distortions that would reveal the passage of these low-frequency gravitational waves. By the 2030s, FAST is expected to have accumulated enough sensitive measurements to study individual sources of such waves, such as supermassive black hole collisions.


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Retrospective with Aurore Eaton: The “space race” arrives at NH in 1959 | Looking back

WITH THE ACTIVATION of the new 6594th Instrumentation Squadron at Manchester Grenier Air Base in October 1959, a new era began.

That year, Grenier AFB housed US Air Force Reserve and New Hampshire National Guard operations. The last regular Air Force unit stationed at the base was the 1610th Air Transport Group, which had been inactivated in 1955.

A component of the US Air Force, the 6594th was a highly specialized technical unit under the operational control of the 6594th Test Wing (Satellite) based in Palo Alto, Calif., Which was part of the Air Force’s ballistic missile division. from Air Research and Development. Order.

The squadron’s mission was to operate a satellite tracking station on the New Boston Bombing Range, the obsolete training ground at Grenier AFB. It would be the first Air Force station built specifically to track satellite orbits, receive telemetry information from them (via radio waves), process that data through complex computers, and send commands and data to the spacecraft.

There was great urgency in this matter, as the Soviet Union had beaten the United States in space with the successful launch of its tiny Sputnik 1 radio-transmitting satellite on October 4, 1957. This development led to the space race, part of the current Cold War crisis between the Soviets and the Americans.

The first successful American satellite was Explorer 1, which was launched on January 31, 1958. It was equipped with a cosmic ray detector to measure radiation in orbit.

On April 1, 1960, the New Boston Satellite Tracking Station began operating with mobile, van-mounted equipment. The construction of the ten buildings on the site is largely completed and radars and other electronic equipment will be installed during the summer.

Military personnel at the satellite base were housed in barracks at Grenier AFB, with the exception of married men with families who rented civilian accommodation in the area. Of the staff of around 300, about 75% were military, while the remainder were civilian employees primarily of the Lockheed Corporation and the Philco Company.

The station was part of a network of monitoring facilities working on the Discoverer satellite program. These satellites were launched into space at Vandenberg Air Force Base in California.

The New Boston station served as the USAF’s satellite test center, facilitating communications between all Discoverer satellite operations nationwide.

As Lieutenant Nicholas Polio, Station Operations Officer, explained in August 1960: “Being able to contact a satellite as it circles the earth at about 18,000 miles per hour is an important feature of the new Boston station… We can talk to the satellite as it passes overhead and tell it what to do and the satellite can respond to us and tell us how it’s doing.

On December 21, 1960, the Tampa (Florida) Times newspaper reported that the latest in the Discoverer satellite series, Discoverer XIX (19), had just been launched the day before at Vandenberg Air Force Base and was now in orbit. It has been reported that, unlike some other satellites in the series, this one does not carry a salvageable capsule.

Looking back on it today, we know it was not one of the top secret “Project Corona” satellites containing photosurveillance equipment to spy on the Soviet Union or China. The CIA used the Discoverer program to cover up this top secret operation. Instead, Discovery XIX’s goal was to study infrared light in the upper atmosphere to help future Midas satellites detect hostile missile fire by reporting heat flashes above normal level.

The planned Midas satellites, which could “see” infrared light through special sensors, would be part of the country’s missile defense system.

At the end of December 1960, the New Boston Satellite Tracking Station briefly made national news.

An article by United Press International, published in numerous newspapers, announced the expected fate of the spacecraft: “The satellite is silent – New Boston, NH – The Air Force said today that the Discovered XIX satellite has lost its transmitting power… the New Boston Radar satellite tracking station said its last contact with the satellite was at 11:34 pm on Christmas Day…[during] the 75th satellite world tour.

Next week: Boston’s new satellite tracking station through time.


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