BSNL employees to protest against cancellation of 4G tender, non-payment of salaries

Leiden, Jul 2: Astronomers have discovered a luminous galaxy caught in the act of reionizing its surrounding gas only 800 million years after the Big Bang.

The research, led by Romain Meyer, PhD student at UCL in London, UK, has been presented at the virtual annual meeting of the European Astronomical Society (EAS).

Studying the first galaxies that formed 13 billion years ago is essential to understanding our cosmic origins. One of the current hot topics in extragalactic astronomy is 'cosmic reionization,' the process in which the intergalactic gas was ionized (atoms stripped of their electrons).

Cosmic reionization is similar to an unsolved murder: We have clear evidence for it, but who did it, how and when? We now have strong evidence that hydrogen reionization was completed about 13 billion years ago, in the first billion years of the universe, with bubbles of ionized gas slowly growing and overlapping.

The objects capable of creating such ionized hydrogen bubbles have however remained mysterious until now: the discovery of a luminous galaxy in which 60-100 percent of ionizing photons escape, is likely responsible for ionizing its local bubble. This suggests the case is closer to being solved.

The two main suspects for cosmic reionization are usually 1) a population of numerous faint galaxies leaking ~10 percent of their energetic photons, and 2) an 'oligarchy' of luminous galaxies with a much larger percentage (>50 percent) of photons escaping each galaxy.

In either case, these first galaxies were very different from those today: galaxies in the local universe are very inefficient leakers, with only <2-3 percent of ionizing photons escaping their host. To understand which galaxies governed cosmic reionization, astronomers must measure the so-called escape fractions of galaxies in the reionization era.

The detection of light from excited hydrogen atoms (the so-called Lyman-alpha line) can be used to infer the fraction of escaping photons. On the one hand, such detections are rare because reionization-era galaxies are surrounded by neutral gas which absorbs that signature hydrogen emission.

On the other hand, if this hydrogen signal is detected it represents a 'smoking gun' for a large ionized bubble, meaning we have caught a galaxy reionizing its surroundings. The size of the bubble and the galaxy's luminosity determines whether it is solely responsible for creating this ionized bubble or if unseen accomplices are necessary.

The discovery of a luminous galaxy 800 million years after the Big Bang supports the scenario where an 'oligarchy' of bright leakers emits most of the ionizing photons.

"It is the first time we can point to an object responsible for creating an ionized bubble, without the need for a contribution from unseen galaxies.

Additional observations with the upcoming James Webb Space Telescope will enable us to study further what is likely one of the best suspects for the unsolved case of cosmic reionization," said Meyer.

Giving each and every app access to personal information stored on Android smartphones such as your contacts, call history, SMS and photos may put you in trouble as bad actors can easily use these access to spy on you, send spam messages and make calls anywhere at your expense or even sign you up for a premium "service", researchers from cybersecurity firm Kaspersky have warned.

But one can restrict access to such information as Android lets you configure app permissions. 

Giving an app any of these permissions generally means that from now on it can obtain information of this type and upload it to the Cloud without asking your explicit consent for whatever it intends to do with your data.

Therefore, security researchers recommend one should think twice before granting permissions to apps, especially if they are not needed for the app to work. 

For example, most games have no need to access your contacts or camera, messengers do not really need to know your location, and some trendy filter for the camera can probably survive without your call history, Kaspersky said. 

While decision to give permission is yours, the fewer access you hand out, the more intact your data will be.

Here's what you should know to protect your data.

SMS: An app with permission to send and receive SMS, MMS, and WAP (Wireless Application Protocol) push messages, as well as view messages in the smartphone memory will be able to read all of your SMS correspondence, including messages with one-time codes for online banking and confirming transactions.

Using this permission, the app can also send spam messages in your name (and at your expense) to all your friends. Or sign you up for a premium "service." You can see and conrol which apps have these rights by going to the settings of your phone.

Calendar: With permission to view, delete, modify, and add events in the calendar, prying eyes can find out what you have done and what you are doing today and in the future. Spyware loves this permission.

Camera: Permission to access the camera is necessary for the app to take photos and record video. But apps with this permission can take a photo or record a video at any moment and without warning. Attackers armed with embarrassing images and other dirt on you can make life a misery, according to Kaspersky.

Contacts: With permission to read, change, and add contacts in your address book, and access the list of accounts registered in the smartphone, an app can send your entire address book to its server. Even legitimate services have been found to abuse this permission, never mind scammers and spammers, for whom it is a windfall.

This permission also grants access to the list of app accounts on the device, including Google, Facebook, and many other services.

Phone: Giving access to your phone means permission to view and modify call history, obtain your phone number, cellular network data, and the status of outgoing calls, add voicemail, access IP telephony services, view numbers being called with the ability to end the call or redirect it to another number and call any number.

This permission basically lets the app do anything it likes with voice communication. It can find out who you called and when or prevent you from making calls (to a particular number or in general) by constantly terminating calls. 

It can eavesdrop on your conversations or, of course, make calls anywhere at your expense, including to pay-through-the-nose numbers, Kaspersky warned.

In a bid to help struggling small businesses in Covid-19 times, Facebook has introduced Shops to help set up a single online store for customers to access on both Facebook and Instagram.

While Facebook Shops is being rolled out from Wednesday, the company will introduce Instagram Shop, a new way to discover and buy products in Instagram Explore, this summer, starting in the US.

The social networking giant also announced that it will invest in features across its family of apps to inspire people to shop and make buying and selling online easier.

"Creating a Facebook Shop is free and simple. Businesses can choose the products they want to feature from their catalogue and then customise the look and feel of their shop with a cover image and accent colours that showcase their brand," Facebook said in a statement late Tuesday.

Any seller, no matter their size or budget, can bring their business online and connect with customers wherever and whenever it's convenient for them.

People can find Facebook Shops on a business' Facebook Page or Instagram profile, or discover them through stories or ads.

"From there, you can browse the full collection, save products you're interested in and place an order — either on the business' website or without leaving the app if the business has enabled checkout in the US," informed the company.

Last month, Facebook announced $40 million in grants for 10,000 small businesses in the US to help them get through these challenging time.

The grants will go to small businesses in 34 locations where Facebook employees live and work.

The company said that in Facebook Shops, users will be able to message a business through WhatsApp, Messenger or Instagram Direct to ask questions, get support, track deliveries and more.

In the future, they will be able to view a business' shop and make purchases right within a chat in WhatsApp, Messenger or Instagram Direct.

Later this year, Facebook will add a new shop tab in the navigation bar, so people can get to Instagram Shop in just one tap.

Facebook said it is making it easier to shop for products in real time.

Soon, sellers, brands and creators will be able to tag products from their Facebook Shop or catalogue before going live and those products will be shown at the bottom of the video so people can easily tap to learn more and purchase.

"We're starting to test this with businesses on Facebook and Instagram, and we'll roll it out more broadly in the coming months," said the company.

Facebook is also working with partners like Shopify, BigCommerce, WooCommerce, ChannelAdvisor, CedCommerce, Cafe24, Tienda Nube and Feedonomics to support small businesses.