Science & Technology

This image is taken by the Event Horizon Telescope (EHT) and shows the shadow of the black hole at the centre of our own galaxy, the Milky Way -Event Horizon Telescope Collaboration

Our galaxy is huge. Our Sun is just one star amongst more than 200 billion in the Milky Way. We like to think that we are special. But our Sun, along with the Earth, is located in the outskirts of our galaxy. We are so far away from the centre of the galaxy, that even travelling at the speed of light, it would still take 26,000 years to get to it.

But the centre of the galaxy is a busy place. There are a lot more stars in that region compared to our place in the galaxy. But there, right at the centre, is also a giant black hole.

Now the existence of black holes was first predicted as a consequence of Einstein’s General Theory of Relativity. The gravity of such objects is supposed to be so intense that not even light can escape from it — hence the name, ‘black hole’. This inference was so strange that Einstein himself doubted their actual existence.

But nature does not rely on scientific reputations. Later work showed that stars much larger than our Sun would indeed end up in the strange state of black holes. Our Sun will never become one. Instead, it will end its life as a white dwarf, a weird object but considerably less strange than a black hole. I don’t know if we should feel happy or sad about our Sun.

Astronomers have unveiled the first image of the supermassive black hole that resides at the centre of our own Milky Way galaxy. This result offers new insights on how giant black holes interact with their surroundings

As you can imagine, it is challenging to find black holes. But they cannot hide themselves completely. When material falls on to a black hole, it usually forms a disk. The material in the disk is sped to incredibly high speeds before it falls into the ‘event horizon’ — the place of no return. Nothing can escape the event horizon, but the disk around it can get very hot due to friction, and can betray its presence by emitting X-rays or other forms of light.

In our own galaxy, astronomers have occasionally detected stars orbiting invisible partners. Cygnus X-1, for example, is one such system, where the disk is so hot that it emits light in the form of high-energy X-rays. We do not see the black hole directly, but all indications suggest that it is one.

These black holes are the end-state of stars that are 20 to 50 times more massive than our Sun. However, astronomers have also discovered black holes that are millions or even billions of times more massive than our Sun. These are called supermassive black holes and they reside almost exclusively at the centre of all large galaxies. Their formation is still a mystery. One such supermassive black hole was depicted in the 2014 sci-fi movie Interstellar.

In 2019, however, astronomers took the image of the shadow of the event horizon of a supermassive black hole at the centre of M87, a galaxy located 55 million light years away. This was the first time humans had directly seen the area right around the event horizon.

Now the existence of black holes was first predicted as a consequence of Einstein’s General Theory of Relativity. The gravity of such objects is supposed to be so intense that not even light can escape from it — hence the name, ‘black hole’. This inference was so strange that Einstein himself doubted their actual existence.

It took an incredible effort. Astronomers combined eight telescopes on four continents to create that image. In effect, they turned the entire Earth into a telescope. This combination of telescopes is called the Event Horizon Telescope (EHT).

The Milky Way also has a supermassive black hole at its centre. We have known about its existence as we have seen its gravity speed up stars and gas clouds around it. In fact, the 2020 Nobel Prize was shared by Andrea Ghez and Reinhard Genzel for observations that showed the existence of this supermassive back hole. We call this black hole Sagittarius A*, shortened to Sgr A*, but pronounced Sagittarius A Star.

But what does it look like? Can we see the light right next to its event horizon?

You would think that imaging our very own supermassive black hole would be easier than the one located at the heart of M87, 55 million light years away. That is not the case. First, our own Sgr A* is much smaller in mass. It is only four million times the mass of our Sun. In comparison, the one in M87 is 1,500 times bigger, or more than six billion times the mass of our Sun.

In 2019, astronomers took the image of the shadow of the event horizon of a supermassive black hole at the centre of M87, a galaxy located 55 million light years away. This was the first time humans had directly seen the area right around the event horizon. It took an incredible effort.

This is important, as it results in material moving faster closer to the event horizon, making it difficult to combine images from the set of telescopes that make up EHT. Second, since we are located in the disk of the galaxy, we have to see through a lot of material between us and Sgr A*.

This past week, the EHT team finally released the first-ever image of the shadow of the supermassive black hole at the centre of the Milky Way. It looks like a doughnut. I should clarify that this is not visible light. Instead, astronomers are seeing this in radio waves.

The central part is dark because any light across that region falls into the black hole, creating a shadow or a silhouette of the event horizon. The size of this dark region is about 65 million km across, comparable to the orbit of planet Mercury in our solar system. Amazingly, the size of the doughnut fits perfectly well with the predictions of Einstein’s General Theory of Relativity.

This is a stunning confirmation of our physics and prior observations. Nature is under no obligation to follow our musings. And yet, here we are.

The next time you are feeling a bit down, perhaps after reading the world news, think about this: tiny beings on a small planet, orbiting an ordinary star in the far outskirts of the Milky Way, have confirmed the existence of a mysterious supermassive black hole at the centre of our galaxy.

The team of Earthlings behind the EHT should get news headlines across the galaxy.

The writer is Professor of Integrated Science & Humanities at Hampshire College in the US. He is also an astronomer affiliated with the Five College Astronomy Department (FCAD) in Massachusetts and hosts shows on the YouTube channel Kainaat Astronomy in Urdu

A rocket of SpaceX Falcon 9 carrying the company’s Crew Dragon spacecraft blasts off to the International Space Station at Nasa’s Kennedy Space Centre in Florida on Friday.—AFP/File The first fully private mission reached the International Space Station early on Saturday with a four-member crew from startup company Axiom Space.

The National Aeronautics and Space Administration (Nasa) has hailed the three-way partnership with Axiom and SpaceX as a key step towards commercialising the region of space known as “Low Earth Orbit,” leaving the agency to focus on more ambitious voyages deeper into the cosmos.

A SpaceX Falcon 9 rocket with the Crew Dragon capsule Endeavor docked at 1229 GMT on Saturday and the crew entered the space station nearly two hours later, after launching from the Kennedy Space Centre in Florida on Friday.

Commanding the Axiom Mission 1 (Ax-1) is former Nasa astronaut Michael Lopez-Alegria, a dual citizen of the US and Spain, who flew to space four times over his 20-year-career, and last visited the International Space Station (ISS) in 2007.

He is joined by three paying crewmates: American real estate investor Larry Connor, Canadian investor and philanthropist Mark Pathy and Israeli former fighter pilot, investor and philanthropist Eytan Stibbe.

“We're here to experience this but we understand there's a responsibility,” Connor said in comments shown on Nasa's live feed.

As the first civilian crew, he said, they “need to get it right.”

The widely reported price for tickets — which includes eight days on the outpost, before eventual splashdown in the Atlantic — is $55 million.

While wealthy private citizens have visited the ISS before, Ax-1 is the first mission featuring an all-private crew flying a private spacecraft to the outpost.

Houston-based Axiom pays SpaceX for transportation, and Nasa also charges Axiom for use of the ISS.

Research projects On board the ISS, which orbits 250 miles (400 kilometres) above sea level, the quartet will carry out 25 research projects, including an MIT technology demonstration of smart tiles that form a robotic swarm and self-assemble into space architecture.

Another experiment involves using cancer stem cells to grow mini tumors, and then leveraging the accelerated ageing environment of microgravity to identify biomarkers for early detection of cancers.

“Our guys aren't going up there and floating around for eight days taking pictures and looking out of the cupola,” Derek Hassmann, operations director of Axiom Space, told reporters at a pre-launch briefing.

In addition, crewmember Stibbe plans to pay tribute to his late friend Ilan Ramon, Israel's first astronaut, who died in the 2003 Space Shuttle Columbia disaster when the spaceship disintegrated upon reentry.

Surviving pages from Ramon's space diary, as well as mementos from his children, will be brought to the station by Stibbe.

The Axiom crew will live and work alongside the station's regular crew: currently three Americans and a German on the US side, and three Russians on the Russian side.

The company has partnered for a total of four missions with SpaceX, and Nasa has already approved in principle the second, Ax-2.

Axiom sees the voyages as the first steps of a grander goal: to build its own private space station. The first module is due to launch in 2024.

The plan is for the station to initially be attached to the ISS, before eventually flying autonomously when the latter retires and is deorbited sometime after 2030.

AN ARTIST’s rendering, provided by Stanford University, shows how double ridges on the surface of Jupiter’s moon Europa may form over shallow, refreezing water pockets within an ice shell.—Reuters PARIS: Ridges that criss-cross the icy surface of Jupiter’s moon Europa indicate there are shallow pockets of water beneath, boosting hopes in the search for extra-terrestrial life, scientists said on Tuesday.

Europa has long been a candidate for finding life in our solar system due to its vast ocean, which is widely thought to contain liquid water — a key ingredient for life.

There is a problem: the ocean is predicted to be buried 25-30km beneath the moon’s icy shell. However water could be closer to the surface than previously thought, according to new research published in the journal Nature Comm­unications.

The finding came partly by chance, when geophysicists studying an ice sheet in Greenland watched a presentation about Europa and spotted a feature they recognized.

“We were working on something totally different related to climate change and its impact on the surface of Greenland when we saw these tiny double ridges,” said the study’s senior author Dustin Schroeder, a geophysics professor at Stanford University.

They realized that the M-sh­aped icy crests on Gree­n­land looked like smaller versions of double ridges on Europa, which are the most common feature on the moon.

Europa’s double ridges were first photographed by Nasa’s Galileo spacecraft in the 1990s, but little was known about how they were formed.

The scientists used ice-penetrating radar to observe that Greenland’s ridges were formed when water pockets around 30 metres (100 feet) below the ice sheet’s surface refroze and fractured.

“This is particularly exciting, because scientists have been studying double ridges on Europa for more than 20 years and have not yet come to a definitive answer for how double ridges form,” said lead study author Riley Culberg, an electrical engineering PhD student at Stanford.

“This was the first time that we were able to watch something similar happen on Earth and actually observe the subsurface processes that led to the formation of the ridges,” he said.

“If Europa’s double ridges also form in this way, it suggests that shallow water pockets must have been (or maybe still are) extremely common.”

Europa’s water pockets could be buried five kilometres beneath the moon’s ice shell — but that would still be much easier to access than the far deeper ocean.

Water closer to the surface would also contain “interesting chemicals” from space and other moons, increasing the “possibility that life has a shot,” Schroeder said in a statement.

“If there is life in Europa, it almost certainly was completely independent from the origin of life on Earth... that would mean the origin of life must be pretty easy throughout the galaxy and beyond,” project scientist Robert Pappalardo said.

BEIJING: Three Chinese astronauts returned to Earth on Saturday after 183 days in space, marking the end of China’s longest crewed mission as it continues its quest to become a major space power.
The Shenzhou-13 spacecraft was the latest mission in Beijing’s drive to rival the United States, after landing a rover on Mars and sending probes to the Moon.
Live footage from state broadcaster CCTV showed the capsule landing in a cloud of dust, with ground crew who had kept clear of the landing site rushing in helicopters to reach the capsule.
The two men and one woman — Zhai Zhigang, Ye Guangfu and Wang Yaping — returned to Earth shortly before 10am Beijing time (0200 GMT), after six months aboard the Tianhe core module of China’s Tiangong space station.
China’s longest crewed mission completes, as plans afoot to launch Shenzhou-14
Ground crew applauded as the three astronauts took turns to report that they were in good physical condition.
Mission commander Zhai was the first to emerge from the capsule roughly 45 minutes after the landing, waving and grinning at cameras as he was lifted by ground crew into a specially designed chair before being bundled into a blanket. “I’m proud of our heroic country,” Zhai said in an interview with CCTV shortly after leaving the capsule.
“I feel extremely good.” The trio originally launched in the Shenzhou-13 from China’s northwestern Gobi Desert last October, as the second of four crewed missions during 2021-22 sent to assemble the country’s first permanent space station — Tiangong, which means “heavenly palace”.
Wang became the first Chinese woman to spacewalk last November, as she and her colleague Zhai installed space station equipment during a six-hour stint.
Zhai, 55, is a former fighter pilot who performed China’s first spacewalk in 2008, while Ye is a People’s Liberation Army pilot.
The trio have completed two spacewalks, carried out numerous scientific experiments, set up equipment and tested technologies for future construction during their time in orbit.
The astronauts spent the past few weeks tidying up and preparing the cabin facilities and equipment for the crew of the incoming Shenzhou-14, expected to be launched in the coming months.

KOUROU, France: Arianespace’s Ariane 5 rocket with NASA’s James Webb Space Telescope onboard lifts up from the launchpad at the Guiana Space Center yesterday. – AFP
KOUROU, France: The world’s most powerful space telescope yesterday blasted off into orbit, headed to an outpost 1.5 million km from Earth, after several delays caused by technical hitches. The James Webb Space Telescope, some three decades and billions of dollars in the making, left Earth enclosed in its Ariane 5 rocket from Kourou Space Centre in French Guiana.
“What an amazing day. It’s truly Christmas,” said Thomas Zurbuchen, head of scientific missions for NASA, which together with the European and Canadian space agencies, ESA and ACS, built the telescope. ESA chief Josef Aschbacher said he was “very happy to say that we’ve delivered the spacecraft into orbit very precisely… that Ariane 5 performed extremely well”.
This was key, since placing the spacecraft in orbit helps economize on the fuel the telescope will need to reach its final destination and perform well after that. It is expected to take a month to reach its remote destination. It is set to beam back new clues that will help scientists understand more about the origins of the Universe and Earth-like planets beyond our solar system.
Named after a former NASA director, Webb follows in the footsteps of the legendary Hubble – but intends to show humans what the Universe looked like even closer to its birth nearly 14 billion years ago. Speaking on social media, Webb project co-founder John Mather described the telescope’s unprecedented sensitivity. “#JWST can see the heat signature of a bumblebee at the distance of the Moon,” he said. All that power is needed to detect the weak glow emitted billions of years ago by the very first galaxies to exist and the first stars being formed.

The telescope is unequalled in size and complexity. Its mirror measures 6.5 m in diameter – three times the size of the Hubble’s mirror – and is made of 18 hexagonal sections. It is so large that it had to be folded to fit into the rocket. That maneuver was laser-guided with NASA imposing strict isolation measures to limit any contact with the telescope’s mirrors from particles or even human breath.

Once the rockets have carried Webb 120 km, the protective nose of the craft, called a “fairing”, will be shed to lighten the load. To protect the delicate instrument from changes in pressure at that stage, rocket-builder Arianespace installed a custom decompression system. “Exceptional measures for an exceptional client,” said a European Space Agency official in Kourou on Thursday.
Crew on the ground were to know whether the first stage of the flight was successful about 27 minutes after launch. Once it reaches its station, the challenge will be to fully deploy the mirror and a tennis-court-sized sun shield. That intimidatingly complex process will take two weeks and must be flawless if Webb is to function correctly. Its orbit will be much farther than Hubble, which has been 600 km above the Earth since 1990.

The location of Webb’s orbit is called the Lagrange 2 point and was chosen in part because it will keep the Earth, the Sun and the Moon all on the same side of its sun shield. Webb is expected to officially enter service in June. – AFP

Crypto-currency exchange BitMart says hackers have stolen about $150m (£113m) worth of tokens from its "hot wallets".
Those affected, one storing Ethereum and one Binance Smart Chain tokens, "carry a small percentage of assets on BitMart and all of our other wallets are secure and unharmed", it said.
But the first security company to notice the hack estimated the stolen tokens were worth closer to $200m.
Bitmart is suspending customer withdrawals until further notice.
The real victims of mass crypto-hacks

RIP Mr Goxx: cryptocurrency-trading hamster dies
"At this moment we are still concluding the possible methods used," it said.
"We are now conducting a thorough security review and we will post updates as we progress." And it would try to "maintain transparency" as it dealt with the aftermath of the attack.
Many investors recommend moving large amounts of crypto-currency not needed for day-to-day trading to "cold" storage, disconnected from the wider internet. Mt Gox handled most of the world's Bitcoin transactions - until 850,000 bitcoins went "missing", shuttering the company. And since then, attacks have been a constant problem for crypto-exchanges and investors. And the latest follows the pattern we are becoming used to - huge amounts of stolen crypto-currency and tiny amounts of detail from the victim.

We do not know:
exactly how much money was stolen
whether it came from customers' wallets or a central pot owned by Bitmart
whether the company will repay users
Past hacks have seen a multitude of outcomes.

Sometimes users are refunded, sometimes they are partially refunded, sometimes the company goes bust and on one occasion a hacker even returned all the money. The only certainty is this hack will add further fuel to the fire for people calling for regulation of these increasingly important companies.

Pakistan and Facebook have partnered to fight Covid-19. — AP/File

ISLAMABAD: Pakistan and Facebook have partnered to fight Covid-19 as the world’s prominent social media platform has provided Marketing Partner Support and Ad Credits for campaigns against the deadly virus and helped the government increase its engagement rates with the public on these posts.

As part of these campaigns, Facebook and some ministries focused on creating videos and messages for boosting “vaccine confidence” amongst the public.

The messaging campaigns helped the Ministry of Health increase its total number of page likes to 470,000, increasing the government’s ability to connect with the people and provide information to its stakeholders.

In a statement, Facebook has said it is important to come together as a community to protect each other through credible health information and support vaccine confidence in the community.

Messages prepared for boosting people’s confidence regarding vaccination

As Covid-19 vaccines are becoming more readily available to larger groups, Facebook launched its new profile frames in partnership with the Ministry of Health that allow users to share their support for getting vaccinated with their family and friends.

Research shows when people see others who they know and trust getting the vaccine, they are encouraged to do the same. A campaign to create awareness about spotting Covid-related misinformation on social media has been launched in Urdu for the Facebook community in Pakistan in partnership with the Digital Media Wing of the Ministry of Information.

This can particularly be effective when it comes to encouraging those who are otherwise unsure about getting themselves vaccinated.

The statement contains a message by Dr Faisal Sultan, Special Assistant to the Prime Minister on Health, who said that 76 per cent of the target population has been reached through social media messaging campaigns.

“The pandemic has brought to the forefront the importance of using digital tools for transmitting critical health information to citizens and keeping them safe and healthy,” Dr Sultan said, adding that Facebook has worked to take aggressive steps to remove harmful misinformation and connect people to resources from health authorities.

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