The Humanion UK Online Daily: National International Universal News Learning and Society Newspaper

Philosophy

Political Philosophy

Political Economics

Medicine

Neurology

Genetics Life Elle The World

Geo-Politics

Regine Humanics Foundation

Africa Asia Australasia Europe North America South America Biochemistry The Eyeonium Epigenomics Biomedicoengineering
Astronomy End Homelessness Beauroblubellogenics Hearteogenics United Kingdom Society Ecology Culture Humanics The Sanctum Mayakardium
Contact Natural Health Social Nature and Solitude Matter World Kollarimaginics

Viimaaginarium

Poets' Letter

Palaeontology Community Sport Biomedicojurisprudence
 

 

 

 

 

 

A Regine Humanics Foundation Ltd Publication: Support The Foundation

||  Year Gamma: London: Tuesday: May 22: 2018 ||

Editorial Page Marine World Microbial World Molecular Biology Universana Neuroniverse Jurisprudence Archaeology The Elleesium Idearian Echoing Eternities
England Northern Ireland Scotland Wales GREEN:K Hope Astrophysics Psychology Write For Us About The Humanion The Humanion Team
The Arkive The Earth The Moon The Sunnara The Universe Cosmovicology Hibiscusjianshii VII London Poetry Festival 2018: October 14-17
October The Poetry Month Poets' Letter Arkive Poetry Pearl Vaartibelladiana Humanion Anthropology V PRAT Conference 2018: New York: October 26-27

Support Regine Humanics Foundation: Advertise in The Humanion

First Published: September 24: 2015

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Radio Astronomy

 

 

 

L: Pulsar J1552+5437, spins 412 times a second. R: Pulsar J0952-0607, rotates 707 times a second and now ranks as the second-fastest pulsar known. Image: NASA:DOE:Fermi LAT Collaboration and ASTRON. Posted: Septmber 07: 2017

The Two New Rather Unrestful Kid-Pulsars on the Galactic-Block: The Low-Frequency Array Radio Telescope in the Netherlands Discovers Two Record-Breaking Rapidly Rotating Pulsars

 

The Low-Frequency Array:LOFAR, a network of thousands of linked radio antennas, primarily, located in the Netherlands, has discovered two new millisecond pulsars by investigating previously unknown gamma-ray sources uncovered by NASA's Fermi Gamma-ray Space Telescope. Pulsar J0952-0607, highlighted near centre, right, rotates 707 times a second and now ranks as second-fastest pulsar known. The location of LOFAR's first millisecond pulsar discovery, J1552+5437, which spins 412 times a second, is shown at upper left. Radio emission from both pulsars dims quickly at higher radio frequencies, making them ideally suited for LOFAR. The top of this composite image shows a portion of the gamma-ray sky as seen by Fermi. At the bottom is the LOFAR "superterp" near Exloo, the Netherlands, which houses the facility's core antenna stations. Image: NASA:DOE:Fermi LAT Collaboration and ASTRON

 

|| September 07: 2017 || ά.

Astronomers have discovered two rapidly rotating radio pulsars with the Low-Frequency Array:LOFAR radio telescope in the Netherlands by investigating unknown gamma-ray sources uncovered by NASA’s Fermi Gamma-Ray Space Telescope. The first pulsar, PSR J1552+5437, rotates 412 times per second. The second pulsar, PSR J0952-0607, rotates 707 times per second, making it the fastest-spinning pulsar in the disk of our Galaxy and the second-fastest known spinning-pulsar overall.

Lighthouse: Pulsars are neutron stars, the remnants of massive stars, that exploded as a supernova, which emits radio waves from their magnetic poles, that sweep past Earth as they rotate. As a result, they act like lighthouses, where we see pulses of radio emission for each rotation. Neutron stars are the size of a city packed in more mass than the Sun. That’s why they are used to study the behaviour of matter under extreme densities. By studying the fastest-spinning pulsars, astronomers hope to discover more about the internal structure of neutron stars and the extremes of the Universe.

New technique: Pulsars shine the brightest at low frequency radio waves and this makes LOFAR an ideal telescope for studying them. “However, finding pulsars with LOFAR is extra hard work because gas and dust between stars disrupts low frequency radio waves.” says Cees Bassa from ASTRON, the Netherlands Institute for Radio Astronomy. That’s why astronomers, usually, look for pulsars at higher radio frequencies.

Bassa and his colleagues have now found a way to overcome this problem. “We have developed a new processing technique, which uses graphics cards, originally, designed for gaming, in the large DRAGNET computer cluster in Groningen to process the LOFAR data.” This cluster is funded through an ERC starting grant to Jason Hessels from ASTRON and the University of Amsterdam.

Millisecond pulsar: Ziggy Pleunis, working together with Bassa and Hessels, was the first to test this technique in a pilot survey with LOFAR in 2016. He struck gold, finding PSR J1552+5437, a pulsar rotating once every 02.43 milliseconds or 412 times per second. This is the first pulsar spinning at millisecond spin periods found with LOFAR.

“As millisecond pulsars are known to emit both high-energy gamma radiation, as well as, radio waves, we, specifically, looked at gamma-ray sources of unknown origin.” says Pleunis, now a PhD student at McGill University in Montreal, Canada.

He was able to show that the gamma-rays from the millisecond pulsar arrived at the same rotational phases as the radio pulses, suggesting a common mechanism for producing both types of radiation.

Record-breaking pulsar: Spurred by the success of the pilot survey, Bassa, Hessels and Pleunis continued searching for millisecond pulsars with LOFAR, and soon, found an even faster-spinning pulsar. Rotating 707 times per second, the PSR J0952-0607 is the fastest-spinning pulsar known in the disk of our Galaxy. Of the known pulsars, PSR J0952-0607 is surpassed in rotation speed only by a pulsar in a dense star cluster outside of the Galactic disk, which rotates 716 times per second.

“Because PSR J0952-0607 is much closer to us than the pulsar in the star cluster, it allows us to study it in much more detail.” says Bassa. Using the Isaac Newton Telescope on the island of La Palma, Spain, the astronomers identified a low-mass star orbiting the pulsar, which provided additional measurements of the distance and energetics of PSR J0952-0607. Future optical observations of the binary companion star will help to determine the mass of the rapidly spinning pulsar, allowing astronomers to discern its composition.

Unseen population: Both pulsars J1552+5437 and J0952-0607 are unexpectedly bright at the low radio frequencies and both quickly become dimmer at higher radio frequencies. This means that they would probably not have been found at higher radio frequencies, where most previous radio telescopes searched for pulsars. Hence, there, may be, an as-yet unseen population of fast-spinning millisecond pulsars in our Galaxy.

“We are finding growing evidence that the fastest-spinning pulsars are the brightest at low radio frequencies and that there, may be, a link with the production of high energy gamma-rays.” says Hessels. If this is, indeed, the case, then LOFAR is expected to find more, possibly, even faster-spinning, millisecond pulsars, whose rotation rate can give astronomers a better understanding of the internal structure of neutron stars.

Two papers detailing Pleunis’ and Bassa’s pulsar discoveries appeared in the Astrophysical Journal Letters on September 05.

LOFAR is a radio telescope composed of an international network of antenna stations and is designed to observe the universe at frequencies between 10 and 250 MHz. Operated by ASTRON, the network includes stations in the Netherlands, Germany, Sweden, the U.K, France, Poland and Ireland.

NASA's Fermi Gamma-Ray Space Telescope is an astrophysics and particle physics partnership, developed in collaboration with the U.S. Department of Energy and with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden and the United States.
ω.
 

Whatever Your Field of Work and Wherever in the World You are, Please, Make a Choice to Do All You Can to Seek and Demand the End of Death Penalty For It is Your Business What is Done in Your Name. The Law That Makes Humans Take Part in Taking Human Lives and That Permits and Kills Human Lives is No Law. It is the Rule of the Jungle Where Law Does Not Exist. The Humanion

||  Readmore   || || ‽: 070917  || ||    Up   ||

 

 

 

 

 

 

 

First Contact: Go with the Speed of Light and Say Hello to the Earth: It Will Still Take 80 Long Minutes to Cross the Vastness of 01.44 Billions Kilometres

Image: ESA:D. O'Donnell

|| August 18: 2016 || ά. On August 10, 2016, ESA’s tracking station at New Norcia, Western Australia, hosting a 35 m-diameter, 630-tonne deep-space antenna, received signals transmitted by NASA’s Cassini orbiter at Saturn, through 1.44 billion km of space.

“This was the farthest-ever reception for an ESA station, and the radio signals, travelling at the speed of light, took 80 minutes to cover this vast distance,” says Daniel Firre, responsible for supporting Cassini radio science at ESOC, ESA’s operations centre in Darmstadt, Germany.

The signal reception was part of a series of tests to prepare several ESA stations to support Cassini’s radio science investigations, planned to begin later in 2016.

This image shows New Norcia station as seen in 2014 by Dylan O’Donnell, an amateur photographer based in Byron Bay, Australia, the blob of light apparently hovering above the antenna is a light artefact, ‘lens flare’.
ω.

|| Readmore || ‽: 190816 || Up ||

 

 

Three-D-printed Antenna Designed for Mega-constellation Small Satellite Platforms

3D-printed antenna: Released 16/03/2016 7:15 am: Copyright ESA–G. Porter
 

|| March 17: 2016 || ά. A prototype 3D-printed antenna being put to work in ESA’s Compact Antenna Test Facility, a shielded chamber for antenna and radio-frequency testing.

“This is the Agency’s first 3D-printed dual-reflector antenna,” explains engineer Maarten van der Vorst, who designed it.

“Incorporating a corrugated feedhorn and two reflectors, it has been printed all-in-one in a polymer, then plated with copper to meet its radio-frequency (RF) performance requirements.

“Designed for future mega-constellation small satellite platforms, it would need further qualification to make it suitable for real space missions, but at this stage we’re most interested in the consequences on RF performance of the low-cost 3D-printing process.”

“Although the surface finish is rougher than for a traditionally manufactured antenna, we’re very happy with the resulting performance,” says antenna test engineer Luis Rolo.

“We have a very good agreement between the measurements and the simulations. Making a simulation based on a complete 3D model of the antenna leads to a significant increase in its accuracy.

“By using this same model to 3D print it in a single piece, any source of assembly misalignments and errors are removed, enabling such excellent results.”

Two different antennas were produced by Swiss company SWISSto12, employing a special copper-plating technique to coat the complex shapes.

“As a next step, we aim at more complex geometries and target higher frequencies,” adds Maarten, a member of ESA’s Electromagnetics & Space Environment Division. “And eventually we want to build space-qualified RF components for Earth observation and science instruments.”

Based at ESA’s ESTEC technical centre in Noordwijk, the Netherlands, the test range is isolated from outside electromagnetic radiation while its inside walls are covered with ‘anechoic’ foam to absorb radio signals, simulating infinite space.

The range is part of ESA’s suite of antenna testing facilities, intended for smaller antennas and subsystems, with larger antennas and entire satellites put to the test in its ‘big brother’, the Hertz chamber.
ω.

Readmore

P: 170316

Up

 

How One Night in a Field Changed Astronomy

 

 

26.09.05: Fifty years ago, scientists Bernard Burke and Kenneth Franklin mistook radio signals from Jupiter for a Maryland farmhand driving home after a late date. It was an easy mistake to make back in 1955 as they set out to map the northern sky using a radio astronomy array in the middle of a rural 96-acre field about 20 miles northwest of Washington, D.C. Before that fateful night, astronomers had never picked up radio signals from any other planet besides Earth.

Testing the array and moving in a southern direction, the two detected bursts of interference. After analyzing the data, they realized that the interference occurred about four minutes earlier each night over several months. Comparing this with other celestial objects moving across the sky, they realized that they had actually been listening to Jupiter. And in fact when other scientists looked back into their records for signals from Jupiter, they found discarded data as far back as five years.  "Our identification of Jupiter as a radio source is not based directly on reasoning, but more on luck," Franklin, a scientist at the Carnegie Institution of Washington, later recounted.



 Image Left: Aerial view of the Mills Cross antenna array in Seneca, Md. The X-shaped array used 64 pairs of unpainted wooden poles with wire stretched across the top to act as one large observatory; to study other directions of the sky, scientists altered the length of the cable between antennas. Click on image for larger version or download alternate image without graphics. Credit: Carnegie Institution of Washington.
 

To get a better idea of what they were hearing, Burke and Franklin compared their new data with what scientists already knew about Jupiter. They realized that the radio bursts matched up with the rotation rate of Jupiter. Scientists had started to understand Jupiter's rotation rate by watching the cloud patterns move across the planet. By listening to the radio bursts, they were able to improve on that information, determining that the planet rotates once in about 10 hours -- more than twice as fast as Earth.

So what does Jupiter sound like? It actually produces a wide range of bursts with different sounds. The most common, called L-bursts, last from a few tenths of a second to several seconds and sound like ocean waves breaking up on a beach. The shorter bursts, known as S-bursts, last a few thousandths to a few hundredths of a second and sound more like popcorn popping or like a handful of pebbles thrown onto a tin roof. Both the University of Florida and the Windward Community College in Hawaii put audible versions online. Nearly all of the planets in our solar system have magnetic fields but Jupiter's is much stronger and closer, making it the only planet scientists can study from the ground in the radio range.

When Burke and Franklin realized the planets emitted radio waves, the field of radio astronomy was about 20 years old and primarily studied the composition, structure, and motion of stars, galaxies, and comets. In fact because radio astronomy has advantages that other forms don't -- namely that it's unaffected by sunlight, clouds, and rain -- it's still an important way of making observations. Sometimes, the radio waves are beamed in a particular direction like a spotlight. In this case, the radio waves appeared every 10 hours, which was close to the known rotation rate of Jupiter.

(Radio astronomy measures the characteristics of radio waves emitted by stars and other celestial phenomena. It led to the discovery of several classes of new objects, including pulsars and quasars.)

"Radio astronomers were studying the Sun and the Milky Way galaxy -- this discovery opened a whole new class of objects to study. Suddenly we realized we could start to learn about planets too... By studying Jupiter and its magnetic fields, we also made discoveries about the Earth and Earth's environment," said Dr. Jim Thieman of the NASA Goddard Space Flight Center. You can read more about other Jupiter discoveries or see Jupiter.

Beside various arrays scattered around the world like the Very Large Array (VLA) in New Mexico, which is roughly one and a half times the size of Washington, DC, spacecraft also carry radio astronomy experiments. The Voyager probes studied four planets and had a radio instrument, as does Cassini, currently studying Saturn and its moons. "They're the children of this discovery," said Dr. Leonard Garcia, a radio astronomer at NASA Goddard Space Flight Center.

To commemorate the discovery, the Maryland Historical Trust placed a roadside marker along River Road near the former Seneca Observatory in April. It reads: "In 1955 scientists Bernard Burke and Kenneth Franklin from the Carnegie Institution of Washington accidentally discovered naturally-generated radio waves from Jupiter using a 96-acre antenna array. This discovery led to greater understanding of planetary magnetic fields and plasmas and opened a new window in our exploration of the solar system."

In 1958 Franklin more aptly put the experience into perspective. "There is no more thrilling experience for a man than to be able to state that he has learned something no other person in the world has ever known before him," Franklin said. "I have been lucky enough to be included in such an event."
Learn more about listening for radio signals from Jupiter and the Sun

( Rachel A. Weintraub : NASA Goddard Space Flight Center)

Readmore

Posted on : November 2015

Up