Astronomers find exoplanet with cloud-free atmosphere
London, May 8: Astronomers have found that a planet outside our solar system, which is similar to Saturn in mass and exceeds the size of Jupiter by 20 per cent, has an atmosphere free of clouds.
The hot gas giant, WASP-96b, periodically transits a Sun-like star 980 light years away in the southern constellation Phoenix.
Using the the European Southern Observatory's Very Large Telescope in Chile, the team studied the atmosphere of WASP-96b when the planet passed in front of its host-star.
This enabled the team to measure the decrease of starlight caused by the planet and its atmosphere, and thereby determine the planet's atmospheric composition.
"We've been looking at more than twenty exoplanet transit spectra. WASP-96b is the only exoplanet that appears to be entirely cloud-free and shows such a clear sodium signature, making the planet a benchmark for characterisation," said lead author of the study Nikolay Nikolov from University of Exeter in Britain.
Just like an individual's fingerprints are unique, atoms and molecules have a unique spectral characteristic that can be used to detect their presence in celestial objects.
The spectrum of WASP-96b shows the complete fingerprint of sodium, which can only be observed for an atmosphere free of clouds, according to the study published in the journal Nature.
It has long been predicted that sodium exists in the atmospheres of hot gas-giant exoplanets, and in a cloud-free atmosphere it would produce spectra that are similar in shape to the profile of a camping tent.
"Until now, sodium was revealed either as a very narrow peak or found to be completely missing. This is because the characteristic 'tent-shaped' profile can only be produced deep in the atmosphere of the planet and for most planet clouds appear to get in the way," Nikolov added.
Clouds and hazes are known to exist in some of the hottest and coldest solar system planets and exoplanets.
The presence or absence of clouds and their ability to block light plays an important role in the overall energy budget of planetary atmospheres.
"It is difficult to predict which of these hot atmospheres will have thick clouds. By seeing the full range of possible atmospheres, from very cloudy to nearly cloud-free like WASP-96b, we'll gain a better understanding of what these clouds are made of," explains study co-author Jonathan Fortney, Professor at University of California, Santa Cruz (UCSC), US.
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Anyone speaking in favour of Pakistan is wrong, it amounts to treason: Siddaramaiah
Bengaluru (PTI): Karnataka Chief Minister Siddaramaiah on Wednesday said that anyone speaking in favour of Pakistan is wrong and it amounts to treason.
He however said that inquiry is on in connection with alleged "mob lynching" of a man, accused of of shouting 'Pakistan Zindabad' slogan, in Mangaluru.
"If the Pakistan Zindabad slogan was shouted, it is wrong, whoever it is. Inquiry is still going on, a case has been registered, let the report come. It will be clear as to what action should be taken against whom," Siddaramaiah said, responding to a question by reporters on killing of a person in Mangaluru allegedly for shouting 'Pakistan Zindabad' slogan.
"If anyone speaks in favour of Pakistan, it is wrong, it is treason," he added.
Home Minister G Parameshwara said, a person was "lynched" in Mangaluru, and while interogating those behind the incident, they have claimed that the victim shouted 'Pakistan Zindabad' slogan.
"It is being further investigated. Only those arrested said this. Nearly 20 people have been arrested now. Police are also finding out about the person (deceased) and his origins. We have taken the incident seriously. Further investigations are on and there were many people who had gone to play the cricket match. They are all being questioned to gather information. Investigation is very serious," he said.
When asked if the deceased person was from Kerala's Wayanad, Parameshwara said, there is such information and it needs to be verified, by establishing his identity and contacting his parents.
To a question, were there any failure on the part of the police as there are reports that they allegedly tried to project it as suicide initially, he said, "We have no such information. If any such thing is there it will come out from the investigation. If any police failures are identified, appropriate action will be taken,"
The Home Minister assured that the case has been taken seriously and there should be no apprehensions that it is being taken lightly.
However, according to police, the deceased has been identified as Ashraf from Pulpalli village in Sultan Bathery Taluk of Wayanad district in Kerala.
The incident had happened during a local cricket match near the Bhatra Kallurti temple in Kudupu village on the outskirts of Mangaluru, on April 27, police said.
Ashraf was allegedly assaulted with sticks, resulting in multiple injuries that led to internal bleeding and shock, police said adding he was declared dead at the hospital.
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