Explained Snippets: Why a blazing meteor over Perth has scientists excited

The meteor came off a particularly large object, believed to have been part of an asteroid, and it passed close to Earth, over a heavily populated city.

By: Express News Service | New Delhi | Updated: August 31, 2018 12:34:30 am
meteor, fireball meteor Australia, perth fireball The fireball, captured by the dashcam of a vehicle outside Perth Tuesday. (Source: Bagus Sugiono, via Reuters)

A spectacular meteor lit up the Perth sky Tuesday night, setting off a search by Australian scientists for the remnants of the celestial object that had caused it. A meteor is a trail of light, also called shooting star, that is created when a space rock enters the Earth’s atmosphere, and vaporises. When shooting stars are so frequently spotted, what makes this one special?

The meteor came off a particularly large object, believed to have been part of an asteroid, and it passed close to Earth, over a heavily populated city. While most meteors burn up completely in that bright streak, very large objects survive — especially if they are travelling at a relatively low speed — and the parts that drop to the ground are called meteorites. CNN quoted Curtin University professor Phil Bland, founder of the Desert Fireball Network that tracks the path of meteors and asteroids, as saying it was “almost certainly” a chunk of asteroid coming through the atmosphere, an event which he said occurs only a couple of times a year. According to NASA, an automobile-sized asteroid enters Earth’s atmosphere about once a year, creates an impressive fireball, and burns up before reaching the surface. While space rocks smaller than about 25 m wide will most likely burn up as they enter the atmosphere, a rocky object in the size range 25 m-1 km would likely cause local damage if it were to hit Earth, while anything larger than 2 km wide could have worldwide effects.

Bland, the Australian scientist, has urged anyone who finds an unusual chunk of rock to give him a call. He told CNN: “It will look strange, it will have a black crust on it and it’ll be kind of slightly rounded in a way that most terrestrial rocks aren’t. It will look distinct, it’ll look odd, also they’re usually a little bit heavier than average rocks.”

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Telling Numbers: From RBI, 300 crore SMSes to people on frauds and rumours

Figures in million. Source: RBI Annual Report 2017-18.

Between November 10, 2017 and June 30, 2018, mobile phone subscribers received over 3,000 million text messages from the RBI under its Public Awareness Campaign. The newly released RBI Annual Report (2017-18) says the campaign included seven messages during this period. These covered various issues, including advice on fictitious offers, rumours about coins, and limiting losses following a fraudulent transaction in one’s bank account. The SMS campaign also has a missed call element resulting in the service provider calling back to provide more information on the subject through a pre-recorded Interactive Voice Response System (IVRS). Over 27 million missed calls were received from mobile phone users, and 20.43 million were called back, data from the report show.

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This Word Means: Transit remand

Maharashtra Police got Navlakha’s transit remand, the High Court stayed it. What are its provisions?

Earlier this week, Delhi High Court stayed a trial court order granting to Maharashtra Police the transit remand of human rights activist Gautam Navlakha (right), one of five arrested in connection with the violence in Bhima Koregaon. Transit remand is defined in Section 80 of the CrPC. If a warrant of arrest is executed outside the district in which it was issued — unless the court that issued the warrant is within 30 km — the person has to be produced in a court of that particular district for remand. For example, if an offence is committed in Delhi but the accused is arrested in Chandigarh, then the police will seek his remand from a court in Chandigarh to transport him to Delhi, so that he can be investigated and tried in Delhi.
While this is transit remand, the broader provisions for remand itself are defined in CrPC Section 76. The court examines the police diary on the nature of the allegations, and grants remand if it is satisfied that the allegations are well founded. In the Navlakha case, the High Court observed that the trial court — that of the Chief Metropolitan Magistrate (Southeast) — had passed the remand order without English or Hindi translations of police documents in Marathi, and the police were not able to “satisfactorily” explain what offence Navlakha had been arrested under.

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