- Tennis power couple de Minaur and Boulter get engaged
- Supermaxi yachts eye record in gruelling Sydney-Hobart race
- Hawaii's Kilauea volcano erupts, spewing columns of lava
- El Salvador Congress votes to end ban on metal mining
- Five things to know about Panama Canal, in Trump's sights
- NBA fines Minnesota guard Edwards $75,000 for outburst
- Haitians massacred for practicing voodoo were abducted, hacked to death: UN
- Inter beat Como to keep in touch with leaders Atalanta
- Man Utd boss Amorim questions 'choices' of Rashford's entourage
- Trump's TikTok love raises stakes in battle over app's fate
- Is he serious? Trump stirs unease with Panama, Greenland ploys
- England captain Stokes to miss three months with torn hamstring
- Support grows for Blake Lively over smear campaign claim
- Canada records 50,000 opioid overdose deaths since 2016
- Jordanian, Qatari envoys hold talks with Syria's new leader
- France's second woman premier makes surprise frontline return
- France's Macron announces fourth government of the year
- Netanyahu tells Israel parliament 'some progress' on Gaza hostage deal
- Guatemalan authorities recover minors taken by sect members
- Germany's far-right AfD holds march after Christmas market attack
- Serie A basement club Monza fire coach Nesta
- Mozambique top court confirms ruling party disputed win
- Syrian medics say were coerced into false chemical attack testimony
- NASA solar probe to make its closest ever pass of Sun
- London toy 'shop' window where nothing is for sale
- Volkswagen boss hails cost-cutting deal but shares fall
- Accused killer of US insurance CEO pleads not guilty to 'terrorist' murder
- Global stock markets mostly higher
- Not for sale. Greenland shrugs off Trump's new push
- Acid complicates search after deadly Brazil bridge collapse
- Norwegian Haugan dazzles in men's World Cup slalom win
- Arsenal's Saka out for 'many weeks' with hamstring injury
- Mali singer Traore child custody case postponed
- France mourns Mayotte victims amid uncertainy over government
- UK economy stagnant in third quarter in fresh setback
- African players in Europe: Salah leads Golden Boot race after brace
- German far-right AfD to march in city hit by Christmas market attack
- Ireland centre Henshaw signs IRFU contract extension
- Bangladesh launches $5bn graft probe into Hasina's family
- US probes China chip industry on 'anticompetitive' concerns
- Biden commutes sentences for 37 of 40 federal death row inmates
- Clock ticks down on France government nomination
- Mozambique on edge as judges rule on disputed election
- Mobile cinema brings Tunisians big screen experience
- Honda and Nissan to launch merger talks
- Police arrest suspect who set woman on fire in New York subway
- China vows 'cooperation' over ship linked to severed Baltic Sea cables
- Australian tennis star Purcell provisionally suspended for doping
- Luxury Western goods line Russian stores, three years into sanctions
- Wallace and Gromit return with comic warning about AI dystopia
Planet spiralling into star may offer glimpse into Earth's end
For the first time astronomers have identified a planet that is spiralling towards a cataclysmic collision with its ageing sun, potentially offering a glimpse into how Earth could end one day.
In a new study published on Monday, a team of mostly US-based researchers said they hope the doomed exoplanet Kepler-1658b can help shed light on how worlds die as their stars get older.
Kepler-1658b, which is 2,600 light years from Earth, is known as a "hot Jupiter" planet.
While similar in size to Jupiter, the planet orbits its host star an eighth of the distance between our Sun and Mercury, making it far hotter than the gas giant in our own Solar System.
Kepler-1658b's orbit around its host star takes less than three days -- and it is getting shorter by around 131 milliseconds a year, according to the study published in The Astrophysical Journal Letters.
"If it continues spiralling towards its star at the observed rate, the planet will collide with its star in less than three million years," said Shreyas Vissapragada, a postdoc at the Harvard–Smithsonian Center for Astrophysics and the study's lead author.
"This is the first time we've observed direct evidence for a planet spiralling towards its evolved star," he told AFP.
An evolved star has entered the "subgiant" phase of the stellar life cycle, when it starts expanding and becoming brighter.
Kepler-1658b's orbit is being shortened by the tides, in a similar process to how Earth's oceans rise and fall every day.
This gravitational push-and-pull can work both ways -- for example the Moon is very slowly spiralling away from Earth.
- Earth's 'ultimate adios'? -
So could Earth be heading towards a similar doom?
"Death-by-star is a fate thought to await many worlds and could be the Earth's ultimate adios billions of years from now as our Sun grows older," the Center for Astrophysics said in a statement.
Vissapragada said that "in five billion years or so, the Sun will evolve into a red giant star".
While the tidally-driven processes seen on Kepler-1658b "will drive the decay of the Earth's orbit towards the Sun," that effect could be counter-balanced by the Sun losing mass, he said.
"The ultimate fate of the Earth is somewhat unclear," he added.
Kepler-1658b was the first exoplanet ever observed by the Kepler space telescope, which launched in 2009. However it took nearly a decade of work before the planet's existence was confirmed in 2019, the Center for Astrophysics said.
Over 13 years, astronomers were able to observe the slow but steady change in the planet's orbit as it crossed the face of its host star.
One "big surprise" was that the planet itself is quite bright, Vissapragada said.
Previously it had been thought this was because it is a particularly reflective planet, he said.
But now the researchers believe the planet itself is far hotter than anticipated, possibly due to the same forces that are driving it towards its star.
P.Cavaco--PC