Showing posts with label astronomy. Show all posts
Showing posts with label astronomy. Show all posts

Tuesday, May 1, 2018

Astronomers say behaviour of ‘most mysterious star in the universe’ is not caused by an alien megastructure

Discovery of Mysterious Star In Universe

Results of an investigation directed in the discovery of an alien mega structure revolving a distant star has been released by a group of 200 researchers. Attention of the astronomers had been drawn by a star known as KIC 8462852 or Tabby’s star due to a strange phenomenon that saw the light it creates ‘inexplicably dimming and brightening sporadically like no other.

This gave rise to a stargazer to recommend that the blinking was due to the presence of a Dyson Sphere which is a theoretical Death Star-style power station surrounding the sun and collecting all its energy. A data has been revealed about the `most mysterious star in the universe’, by the scientist making this recommendation, from an investigation fund utilising $100,000 raised in a campaign of Kickstarter.

An astrophysics assistant professor at Pen State Department of Astronomy, Jason Wright, stated that they had been anticipating that once they eventually caught a dip happening in real time, they could see if the dips had the same depth at all wavelengths.

He further commented that if they were almost the same, it would indicate that the cause was something opaque, such as an orbiting disk, planet or star or also large structures in space and the latest research rules out alien megastructue though it tends to raise the plausibility of other phenomena being behind the dimming’.

Las Cumbres Observatory

It had been suggested earlier that the dimming had been due to a planet or a swarm of comets. Tabetha Boyajian of Louisiana State University commented that the dust is most likely the cause why the light of the star seems to dim and brighten.

 The latest data portrays that the different colours of light have been blocks at various intensities and hence whatever tends to pass between us and the star is not opaque as it would be expected from a planet or alien megastructure.

The star had been carefully observed by the scientists through the Las Cumbres Observatory from March 2016 to December 2017. There had been four distinct episodes starting in May 2017 when the light of the star had dipped. Crowdfunding campaign supporters had nominated and voted to name these episodes where the first two dips had been named Elsie and Celeste.

The last two had been named after the ancient lost cities- Scotland’s Scara Brae and Cambodia’ Angkor.The authors have mentioned that in several ways what tends to occur with the star is like these lost cities. They had written that `they are ancient; we are watching things that happened more than 1,000 years ago. They are almost certainly caused by something ordinary, at least on a cosmic scale and yet that makes them more interesting, not less. But most of all, they are mysterious’.

New Era of Astronomy

The technique, by which the star is being researched, is done by collecting and analysing abundance of data from an individual target brings in a new era of astronomy. Tyler Ellis an LSU doctoral candidate studying the star had commented that they are gathering much data on an individual target and this project is reflective of changes in astronomy with the access of this abundance of data.

Scientists going through huge amount of data from NASA Kepler mission had been the ones to identify the unusual behaviour of the star in the initial stage. The main purpose of the Kepler mission was to locate planet which is done by detecting the periodic dimming that takes place from a planet moving in front of a star and so blocking out a small bit of starlight.

Planet Hunters, an online citizen science group had been established in order that volunteers could assist in classifying light curves from the Kepler mission as well as to search for such planets. Boyajian had stated that if it was not for people with unbiased look on our universe, this unusual star would have not been noticed and again without the support of the public, for this dedicated observing run, they would not have this huge amount of data.

Models - Circumstellar Material

Wright has mentioned that there are models involving circumstellar material such as exocomets which had been the original hypothesis of Boyajian’s team that seem to be consistent with the data they had. Moreover Wright also pointed out that some astronomers preferred the idea that nothing seems to be blocking the star and that it just seemed to get dimmer on its own, this also is consistent with the data of summer.According to Boyajian it seems to be quite exhilarating and is grateful to all those who had made their contributions to this in the past year, namely the citizen scientists together with their professional astronomers. He stated that it was quite humbling to have all of them contributing in numerous ways of helping in figuring out the same.

Wednesday, April 5, 2017

Radiation from Nearby Galaxies Helped Fuel First Monster Black Holes

Galaxy

Presence of Supermassive Blackholes – Confusion of Astronomers

The presence of supermassive black holes towards the beginning of the creation has given rise to confusion to astronomers from the time of their discovery, more than a decade back. A supermassive black hole is considered to be formed over billions of years, though more than two dozen of these behemoths have been seen within 800 million years of the Big Bang 13.8 billion of years ago.

A team of researchers from Dublin City University, Georgia Tech, Columbia University as well as the University of Helsinki, in their new study in the journal `Nature Astronomy’, showed signs of one concept on how these antique black holes which seemed to be around billion times heavier than the sun could be formed and seemed to put on weight rapidly.

The researchers showed that a black hole could swiftly develop towards the core of its host galaxy if an adjoining galaxy and seemed to emit sufficient radiation to switch off its capability to form stars. Hence restricted, the host galaxy is inclined to cultivate till it ultimately collapses, forming a black hole which feeds on the left over gas, and later, dust, dying stars, and perhaps other black holes, that become great colossal.
  

Collapse of Galaxy/Formation of a Million-solar-mass BlackHole


According to co-author, Zoltan Haiman, an astronomy professor at Columbia University commented that the collapse of the galaxy and the formation of a million-solar-mass black hole took around 100,000 years — a glitch in planetary times and a few hundred million years later, it had grown into a billion-solar-mass supermassive black hole.

This seemed to be much quicker than expected. Stars and galaxies in the early creation had been formed as molecular hydrogen cooled and flattened to primordial plasma of hydrogen and helium. This environment had limited black holes from growing very big since molecular hydrogen would turn gas into stars adequately far away to escape the black holes, gravitational pull.

Astronomers had come up with a number of methods that supermassive black holes could have overcome this obstacle. Haiman together with his colleagues, in their 2008 research had hypothesized that radiation from a considerable nearest galaxy could divide molecular hydrogen into a atomic hydrogen causing the nascent black hole together with its host galaxy to collapse instead of spawning new clusters of stars.

Research - Effects of Gravity/Fluid/Dynamics/Chemistry/Radiation

A study after this, headed by Eli Visbal a postdoctoral researcher a Columbia then had summed that the nearby galaxy could have been around 100 million times much bigger than the sun to emit adequate radiation in order to stop star formation.

 However, being comparatively rare, adequate galaxies of this size seemed to exist in the initial creation to describe the supermassive black holes witnessed so far. Presently the study, headed by John Regan, a postdoctoral researcher at Ireland’s Dublin City University, had displayed the procedure utilising software established by Columbia’s Greg Bryan wherein his study comprised of the effects of gravity, fluid dynamics, chemistry as well as radiation.

 Few days subsequently of crunching the numbers on a processer, the researchers established that the adjoining galaxy could have been smaller as well as closer than earlier assessed. A study co-author John Wise, the Dunn Family Associate Professor in Georgia Tech’s College of Physics, had commented that the nearby galaxy could not be too close, or too far away, and similar to the Goldilocks principle, excessively hot or cold.

Monday, November 14, 2016

New Theory: How Earth Got Its Moon

How Earth Got Its Moon

Origin of Moon – Impact Theory


The moon is extremely important to the Earth that provides the source for several calendars which tends to affect the tides of ocean. Many have been questioning on how it got there. A team of scientists have now utilised complex modelling in order to propose a new theory which involves violent collision that tends to vaporize much of the planet. Lead researcher, Matija Cuk had mentioned in a news release that in spite of smart people working on this issue for 50 years; they have still been discovering the basic things regarding the earliest history of the world.

The results published in the journal Nature had been co-authorised by scientist at the University of California, Davis, Harvard University, the University of Maryland and the SETI Institute, an organization which is recognized better for its attempt in locating alien life and where Cuk is said to be a researcher.

The origin of moon, had been the `impact theory’ for decades as one of the leading explanations, It is said that billions of years ago, Earth and Mars sized protoplanet known as Theia had collided. The wreckage had formed a ring round the equator of the Earth and had been ultimately drawn together by gravity thus forming the moon.

Debris of Theia


The moon could have been developed much nearer to Earth and ultimately moved farther away. According to Davis, senior author Sarah Stewart, professor of earth and planetary sciences at the University of California, had informed CBC News that this idea had come around before computers could do detailed simulations of planet formation. Computer simulations now portray that the impact could have developed the moon mainly out of the debris of Theia though scientists are of the opinion that the Earth and moon tend to have unusually identical chemical makeups. Stewart states that it really puts a brake on the giant impact hypotheses.

Moreover, if the moon had been formed from the debris surrounding the equator, presently we would expect it to circle alongside the equator and the fact is, its orbit is tilted five degrees. Astronomer and co-author Douglas Hamilton of the University of Maryland had mentioned in a statement that this large tilt seems to be very unusual and till now there has not been a good explanation for the same. However it can be understood if the Earth had a more dramatic early history than suspected earlier.

Higher Energy Effect


The collision, under the new, tweaked theory could have taken place at a much sharper angle and could have been more powerful. Stewart commented that it takes a lot of energy to change an orbit. The latest model recommends a much higher energy effect which could have been much more violent that it vaporised not only Theia but the Earth also.Molten and vapour material may have shaped a huge cloud, about 500 times the extent of the present Earth.

Some of the material may have cooled and could have fallen back to Earth and the remaining may have designed the moon. The bigger collision could have been much more powerful and at that angle that it could have hit the rotational axis of the Earth between 60 and 80 degrees causing the planet to spin speedily that days could last only two hours.

Wednesday, August 10, 2016

The Mystery of Space Roar

ARCADE

ARCADE – Scientific Instrument Package Sent in Space – Helium Balloon


Early in July 2006, ARCADE – Absolute Radiometer for Cosmology, Astrophysics and Diffuse Emission, a scientific instrument package had been sent in the air through a Helium Balloon. Columbia Scientific Balloon Facility of NASA in Palestine Texas had been the point of launch and had reached an altitude of 120,123 feet at the point one would call `Space. A research scientist at NASA’s Goddard Space Flight Centre, Dr Alan Kogurt who was also the head of the ARCADE team had been looking for unusual Radio Emission which are rather challenging to monitor on ground level due to the increased Radio noise found on the ground.

 The radio emissions stemming from space has been known since the discovery by Nikola Tesla and probably Karl Jansky. It is said that there is a fragment and uniform radio emission which is believed to have been the result of the Big Bang, Cosmic Background Radiation. Dr Kogurt had been hoping to find confirmation of the Cosmic Background as well as a few new radio emission points and what he found was one of those historic `Wow Moments’ in his scientific research. What he has learned is noted in his own words `The universe really threw us a curve’. Instead of the faint signal we hoped to find, here was this booming noise six times louder than anyone had predicted’
ARCADE

NASA Discovered `Space Roar’


NASA found something known as `Space Roar’ which is a sound that is six times louder than anything one could have ever expected. It is a signal that has been discovered by NASA’s ARCADE instrument that is presently without any explanation.

In space no one could hear you scream since there is no medium through which sound can move. Space roar is not actually a sound but it is radio waves. Space roar had first been discovered by ARCADE and has a very fancy name for some very fancy equipment which NASA had attached to a big balloon which was sent into space. ARCADE had intended to look for radio signals from distant galaxies.

Since radio is so commonly used and also utilised in creating auditory signals, it seems easy to overlook that it is just another form of light. It is much less energetic than the visible light where our eyes are not accustomed for it though it tends to behave in the same manner.

Intended to Pick Faint Radio Signals of Distant Stars


A star releasing radio waves is not much different from the sun releasing visible light. Actually to someone far away or far in the future, the sun possibly is emanating primarily radio waves.ARCADE, when sent out in space was intended to pick up the faint radio signals of distant stars. Instead it received strong blare of radio and the input has been described as `boom’ by those who have been researching on it.

After some research done, the idea had been ruled out that it had been just very loud early stars. They also ruled out that it was coming from the dust of our own galaxy and was just a blast of radio, - `space roar’ which seemed to be part of the background noise with no explained reason. Though space roar has vexed the interest of several, there is yet no explanation for the same.

Saturday, July 9, 2016

Astronomy and Astrology of the Medieval Islamic World

Astronomy_5

Medieval Period – Scientists’ Contribution to Astronomy


Scientists during the medieval period had made great contribution to the field of astronomy. They had updated methods of measuring and calculating the movements of heavenly bodies while their work was centred on ancient sources from Greece, India and Iran, they continued to progress models of the universe as well as the movements of the planets in it. In the midst of the eighth and tenth centuries, Baghdad had been a main center of study under the Abbasid caliph al-Mansur and al-Ma’mum though the local rulers through the region, in Cairo, Rayy, Isfahan together with the other cities had supported scientific exploration.

Scientists during that time, translated studies in Sanskrit, Pahlavi and Greek into Arabic and Arab Bedouin was recorded for the first time. The Persian Pahlavi and the Indian Sanskrit sources imparted medieval astronomers methods to calculate the position of heavenly bodies as well as in creating tables recording the movements of the sun, moon and the five known popular planets. The Bedouin traditions contain information on fixed stars, the passage of the sun and moon via the zodiacal signs as well as lunar mansion together with the seasons and connected phenomenon.
Astronomy_4

Aristotle’s model of Universe – Widely Accepted


The form of information had been refined in section due to the specific needs of Islam, the religion need the skill to determine the time and direction of Mecca for prayer, accurately, the moment of sunrise and sunset for the purpose of fasting during Ramadan. It was also needed for fixing the appearance of the moon which marked the beginning of a new month, leading to the refinement of scientific instruments. This was an improvement in systems in making observations together with the creation of new calendrical methods.

Astronomy_3


Another section of study had been led by astronomers interested in a correct understanding of the movements of the planet in reply to the inquiries of Greek in this area. The most influential Greek texts were more concerned in developing a model of the universe and the movement of the heavenly bodies in it. However the literature planned two diverse approaches to this issue. Aristotle’s model of the universe, on the other hand with the earth at its centre and the sun, moon, planets and the fixed stars that rotate around it, in uniformly turning spheres had been widely accepted.
Astronomy_2

Astrology – Predicts Influence of Heavenly Bodies on Events on Earth


The work of Ptolemy instead pursued a purely theoretical, geometrical representation of the universe centred on accurate observation even though it differed with the ideal Aristotelian model of stars and planets.Astrology tends to seek in predicting the influence of the heavenly bodies on events on earth, depending on understanding the movement of the planet together with the skills to calculate their position in the near future.
Astronomy



This way, astrology had been considered as a branch of astronomy with serious scientist like Abu Ma’shar al-Balkhi, al-Biruni and Nasir al-Din al-Tusi who wrote astrological treatises. The amount of medieval theologians, jurists and philosophers who had written anti-astrology tract tends to indicate that it was controversial and not accepted universally as a scientific or ethical practice.

Saturday, December 5, 2015

Enceladus’s Underground Ocean That Could Host Life

Enceladus

Saturn’s Enceladus – Similar to Deep Oceans on Earth

An enormous breakthrough in the search for life on other planets has been revealed by scientists. Spacecraft of Nasa’s Cassini had provided scientist with the first clear evidence that moon of Saturn, Enceladus tends to exhibit signs of current day hydrothermal activity which is similar to that seen in the deep oceans on Earth. If the same is confirmed, it would make the moon Enceladus, the only known body in the solar system beside the Earth where hot water as well as rocks tend to interact underground.

 It is said that the activity would make the moon a much more attractive place for hunting microbial life. Astrobiologist consider the 314 mile wide Enceladus as one of the best bets of the solar for hosting life beyond the Earth. The satellite is said to be covered by an icy shell and is geologically active, as proved by the powerful geysers which tend to blast constantly from its south polar region. The clouds tend to contain substantial amount of water, which according to the scientists have originated from a subsurface ocean. Earlier research recommended that the ocean is in contact with the rocky mantle of Enceladus with possibility of all kinds of interesting chemical reactions.

No Sunlight Flowing in Underground Sea

The scientists discovered weird life form in hydrothermal vents on the ocean bottom, on Earth, where there seems to be no sunlight flowing through the underground sea of Enceladus. However, any microbes which tend to exist there could gain access to two different sources metabolism-supporting energy sources, molecular hydrogen and the heat provided by hydrothermal vents.

NASA states that the implications of this activity on a world besides our planet tend to open up exceptional scientific possibilities. These discoveries add to the possibility that Enceladus which comprise of a subsurface ocean, displaying remarkable geologic activity could contain an atmosphere which could be suitable for living organisms, according to John Grunsfeld astronaut and associate administrator of NASA’s Science Mission directorate in Washington.He further added that the location in our solar system where the extreme environments takes place in which life could exist, may bring us closer to answering queries to : `are we alone in the Universe’.

Hydrothermal Activity – Seawater Infiltrates/Reacts with Rocky Crust

Hydrothermal activity tends to take place when the seawater infiltrates and reacts with rocky crust and arises as a heated mineral laden solution, which is a natural event in the ocean on Earth. As per two science papers, the effects were the first clear indications that an icy moon could have same on-going active processes. The first paper published in the journal Nature relates to microscopic grains of rock that were noticed by Cassini in the Saturn system.

A four year extensive analysis of data from the spacecraft, laboratory experiments and computer simulations directed the researchers to the conclusion that the tiny grains probably formed when the hot water containing dissolved minerals from the moon’s rocky interior travelled upwards coming in contact with cooler water. According to the researchers, the subsurface sea of Enceladus contains dissolved sodium chloride like the Earth’s ocean but is full of sodium carbonate, also known as washing soda or soda ash. Study team members state that this alien water body is possibly similar to terrestrial soda lakes like the Mono Lake in California than it is to the Atlantic as well as Pacific oceans.

Thursday, October 23, 2014

Naga Fireballs


Naga
Naga Fireballs – Unexplained Phenomena

The Naga fireballs also known as the Mekong lights and `bung fai paya nak’ by the locals is a phenomenon with an unconfirmed source stating it to be often seen in Mekong river in Thailand. They are one of the well documented though unexplained phenomena in the world where every year on the night of Wan Awk Pansa during October, many spectators assemble on the banks of the river Mekong in Thailand and Laos to witness the legendary Naga breathe forth balls of fire from the river and many have watched this scene every year during their entire life.

The balls seem to be reddish in colour with diverse sizes ranging from small sparkles up to the size of basketballs which rises quickly to a couple of hundred metres before disappearing while the number of fireballs which have been reported varies between tens and thousands on each night.

It is believed that the legendary Naga breathes forth balls of fire from the river which slowly and silently rises from the river before ascending high into the air where they tend to disappear in the sky. This spectacular scene is seen at the time of the festive night which is believed to be of natural origin rather than an organized display by anyone.


Naga Fireballs
Naga Fireballs – Least Known/Most Spectacular Phenomena

According to Manas Kanaksin, a doctor from Nong Khai, is of the opinion that fermenting sediment at the bottom of the river could cause pockets of methane gas formation and the position of the earth in relation to the sun during those days could cause them to rise, spontaneously igniting in the presence of ionized oxygen.

The lights have been replicated by Italian chemist Luigi Garlaschelli and Paolo Boschetti who have added chemicals to the gases, formed by rotting compounds. Other researchers have dismissed this theory stating that the bottom of the rocky river does not have much sediment and the water’s turbulence could break up any such methane bubbles before reaching the water’s surface. The Naga fireballs of the Mekong seem to be one of the least known and the most spectacular of phenomena ever seen.

Naga Fireballs 1
Mythology – Naga a Gigantic Hooded Snake

The Naga fireballs always tend to appear on the night of the full moon in October or November which indicates the end of the Buddhist rainy season retreat. These lights have been named after the Naga with a belief that it is the mythical serpent inhabiting the waters that shoots the fireballs into the air.

According to mythology, it is believed that Naga is a gigantic hooded snake which is very prominent in Indian and south-eastern Asian cultures and is said to be an actual physical animal though with a supernatural spirit. The people in that region also believe that the animal lives in the local waters but it is the fireball which has drawn the attention of the people who tend to be both sceptical and believing.

However, the ancient Naga fireballs phenomena seem to be a locally held understanding and do not seem to be reliably documented before the middle of the 20th century. There are several theories regarding the origin of the light but the same has not been explained till date.