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Landmark Achievement: 6 Astronomers from India Discover Giant Radio Galaxies (GRGs)

A team of 6 astronomers from India have reportedly discovered Giant Radio Galaxies (GRGs) which are the largest known galaxies in the universe

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Giant Radio Galaxies
Out of total known galaxies, only 300 have been classifies as Giant Radio Galaxies. Wikimedia
  • Six astronomers from India have recently discovered the largest galaxies known to the universe, called Giant Radio Galaxies (GRGs)
  • Only 300 out of total number of galaxies are classified as Giang Radio Galaxies
  • The research was successful taking into account the research of last 6 decades of radio astronomy

July 06, 2017: A team of six astronomers from India has made a landmark discovery. Using the research from last six decades of radio astronomy and a 20-year-old survey, the team has detected the existence of Giant Radio Galaxies (GRGs).

Giant Radio Galaxies are known to be the largest galaxies in the universe. The reason for their large size is unknown as of now. As one of the lead researcher, Pratik Dabhade from Inter-University Centre for Astronomy and Astrophysics (IUCAA), explains in the study, “The huge size of GRGs has defied any theoretical explanation so far. Our work will help in understanding how these galaxies grow to be so large.”

The other researchers also involved include Joydeep Bagchi (IUCAA), Mamta Pommier (CNRS Observatoire de Lyon), Madhuri Gaikwad (Max Planck Institute Bonn), Shishir Sankhyayan (IISER Pune) and Somak Raychaudhary (IUCAA).

Also Read: “Do not Stand and Drink Water”: Here is Why it is often said so

Their research has been published in Journal Monthly Notices of the Royal Astronomical Society. The Giant Radio Galaxies are found co-existing with a supermassive black hole at the core of center of the nucleus. High energy particles are discharged at the speed of light which emerges into two giant radio lobes.

The Giant Radio Galaxies are known to be the last stage of evolution of galaxies, mainly because of their massive size. However, these galaxies are visible only through radio telescopes.

– by Saksham Narula of NewsGram. Twitter: @Saksham2394

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Oldest recorded solar eclipse occurred 3,200 years ago

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Solar eclipse

Cambridge University researchers have pinpointed the date of what could be the oldest solar eclipse yet recorded. The event, which occurred on October 30, 1207 BC, is mentioned in the Bible, and could help historians to date Egyptian pharaohs.

“Solar eclipses are often used as a fixed point to date events in the ancient world,” said Professor Colin Humphreys from University of Cambridge’s Department of Materials Science & Metallurgy.

Using a combination of the biblical text and an ancient Egyptian text, the researchers were able to refine the dates of the Egyptian pharaohs, in particular, the dates of the reign of Ramesses the Great, according to the study published in the journal Astronomy & Geophysics.

The biblical text in question comes from the Old Testament book of Joshua and has puzzled biblical scholars for centuries.

It records that after Joshua led the people of Israel into Canaan, a region of the ancient Near East that covered modern-day Israel and Palestine – he prayed: “Sun, stand still at Gibeon, and Moon, in the Valley of Aijalon. And the Sun stood still, and the Moon stopped until the nation took vengeance on their enemies.”

“If these words are describing a real observation, then a major astronomical event was taking place – the question for us to figure out is what the text actually means,” Humphreys said.

“Modern English translations, which follow the King James translation of 1611, usually interpret this text to mean that the Sun and Moon stopped moving,” Humphreys said.

“But going back to the original Hebrew text, we determined that an alternative meaning could be that the Sun and Moon just stopped doing what they normally do: they stopped shining. In this context, the Hebrew words could be referring to a solar eclipse, when the Moon passes between the earth and the Sun, and the Sun appears to stop shining,” Humphreys said.

This interpretation is supported by the fact that the Hebrew word translated ‘stand still’ has the same root as a Babylonian word used in ancient astronomical texts to describe eclipses, he added.

Independent evidence that the Israelites were in Canaan between 1500 and 1050 BC can be found in the Merneptah Stele, an Egyptian text dating from the reign of the Pharaoh Merneptah, son of the well-known Ramesses the Great, the study said.

The large granite block, held in the Egyptian Museum in Cairo, says that it was carved in the fifth year of Merneptah’s reign and mentions a campaign in Canaan in which he defeated the people of Israel.

Earlier historians had used these two texts to try to date the possible eclipse, but were not successful as they were only looking at total eclipses, in which the disc of the Sun appears to be completely covered by the moon as the moon passes directly between the earth and the sun.

What the earlier historians failed to consider was that it was instead an annular eclipse, in which the Moon passes directly in front of the Sun, but is too far away to cover the disc completely, the researchers said.

In the ancient world, the same word was used for both total and annular eclipses.

The researchers developed a new eclipse code, which takes into account variations in the Earth’s rotation over time.

From their calculations, they determined that the only annular eclipse visible from Canaan between 1500 and 1050 BC was on 30 October 1207 BC, in the afternoon.

If their arguments are accepted, it would not only be the oldest solar eclipse yet recorded, it would also enable researchers to date the reigns of Ramesses the Great and his son Merneptah to within a year.

Using these new calculations, the researchers determined that Ramesses the Great reigned from 1276-1210 BC, with a precision of plus or minus one year.(IANS)

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Researchers Claim The Existence Of Planet Nine

Researchers from an American University have laid evidences to prove the presence of Planet Nine

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Planet Nine
Kuiper Belt indicates the presence of Planet Nine
  • The science communities since a long time have been debating upon the existence of Planet Nine. 
  • Space highlights different shreds of evidence based on which scientists are stating the claim.

What Is Planet Nine?

Planet Nine is a hypothetical planet present in the far outer Solar System, whose mass is estimated to be 10 times more than the mass of Earth. The planet is said to be 20 times farther than the sun than Neptune is.

What Do Researchers Have To Say?

Dr Konstantin Batygin, a planetary astrophysicist at the California Institute of Technology, said that there were five different lines of observational evidence which pointed to the existence of Planet Nine. He stated that if this theory does not sound believable, then people would have to come up with the answers of the five pieces of evidence which could lead to further confusion.

Also Read: Five Students from Telangana Selected for the NASA Human Exploration Rover Challenge

Batygin in 2016 published a study examining the six known objects in the Kuiper Belt, a  circumstellar disc in the Solar System beyond the planets that extends from the orbit of Neptune towards interstellar space.

The study examines all the objects have elliptical orbits pointing in the same direction and are tilted the same way. These serve as evidence to the planet’s existence.

It is being said that the objects are tilted 30 degrees downward compared to the plane where the eight official planets circle the sun. Researchers also made use of computer simulations of the solar system including the Planet Nine and to demonstrate that there should be more objects tilted a whopping 90 degrees to solar plane. It was revealed that five such objects, which fit these parameters were already known.

The study led to the birth of two more ideas. Researchers said that this planet could have tilted the planets of the solar system during the last 4.5 billion years.

Planet Nine’s existence could also tell the reason as to why Kuiper Belt objects orbit in the opposite direction as compared to other things in the solar system.

-Prepared by Megha Acharya of NewsGram.

(the story was originally published in PTI)

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Astronomers Discover New ‘Mid-size’ Black Hole 100,000 Times More Massive than the Sun

Scientists predict that nearly 100 million of these small black holes should exist in the Milky Way, however only about 60 have been found till now

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Black hole in milky way
A near-infrared image of a black hole at the center of the Milky Way galaxy as seen with Hubble Space Telescope/NICMOS. (NASA/STScI) (VOA)
  • Researches in Japan have discovered a super-massive black hole in Milky Way Galaxy
  • The black hole is believed to weigh as much as 400 suns
  • According to studies,  at least 100 million of these small black holes should exist in the Milky Way

Japan, September 5, 2017 : Astronomers have found new evidence for the existence of a mid-sized black hole, considered the missing link in the evolution of super-massive black holes.

Astronomers in Japan found the possible black hole in our own Milky Way galaxy, a long-theorized object which is bigger than the small black holes formed from a single star, but still much smaller than giant black holes such as the one at the center of the Milky Way.

Black holes are difficult to find because they do not emit any light. However, scientists can detect them by their influence on nearby objects.

The astronomers in Japan found new evidence of the so-called intermediate-mass black hole when they turned a powerful telescope in Chile’s Atacama desert on a gas cloud near the center of the Milky Way. The gases in the cloud move at unusual speeds, and the scientists believed they were being pulled by immense gravitational forces. They say the gravitational force is likely caused by a black hole measuring about 1.4 trillion kilometers across.

black hole in Milky way galaxy
Radio telescope antennas of the ALMA (Atacama Large Millimeter/submillimeter Array) project are seen in the Atacama desert, some 1500 km north of Santiago, Chile, VOA

The findings are published in the journal Nature Astronomy.

Theoretical studies predict at least 100 million of these small black holes should exist in the Milky Way, however only about 60 have been found.

The possible mid-sized black hole is much smaller than the super massive black hole that is located in the center of the galaxy, known as Sagittarius A, which weighs as much as 400 million suns.

“This is the first detection of an intermediate-mass black hole candidate in the Milky Way galaxy,” said the study’s leader, Tomoharu Oka from Keio University, Japan.

If confirmed, the intermediate-mass black hole could help explain how supermassive black holes operate. One theory is that supermassive black holes, which are at the center of most massive galaxies, are formed when smaller black holes steadily coalesce into larger ones. However, until now no definitive evidence has existed for intermediate-mass black holes that could indicate a middle step between the small and massive black holes already detected.

Researchers say they will continue to study the intermediate-mass black hole candidate in the hope of confirming its existence. (VOA)