Sydney woke up to a scorcher early this morning, with the weather reaching 28 degrees at sunrise.

In the six decades since the Soviets first launched Yuri Gagarin into space in 1961, there have been a handful of space-related disasters.

Launching humans into space is an inherently risky practice.

To prepare astronauts for the microgravity environment of space, they take part in rigorous training and simulations to get their bodies used to zero gravity and weightlessness.

Time spent in space can impact blood pressure, spatial orientation, balance, hand-eye coordination and even bone density.

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Two American astronauts, who were launched on a test mission to the International Space Station back on June 5 last year, have been left indefinitely stuck in space due to problems with spacecraft the Boeing Starliner.

When Barry 'Butch' Wilmore and Sunita Williams launched into space, they only expected to stay for eight days.

Initially, it was expected Wilmore and Williams would return to earth by February 2025.

Now, after spending Christmas and New Year's at the International Space Station, the Space X-led mission to rescue the pair has been delayed even further.

Elon Musk's Space X delayed the mission over a last-minute technical issue last week.

The long-awaited mission is now under way after the Falcon 9 rocket blasted off from Nasa's Kennedy Space Center in Florida.

Over the past nine months, Wilmore and Williams have faced the tough reality that their bodies will slowly but surely feel the impacts of extended time spent in space.

Though they would have been well-prepared, some side effects are impossible to avoid.

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What are the physical effects of prolonged exposure to zero gravity?

According to NASA, extended periods without the earth's gravity can have an impact on human bones. Zero-gravity means the bones in the lower portion of the body (legs, hips, spine) are doing significantly less work.

Weight-bearing bones lose an average of 1 to 1.5 per cent of mineral density (bone mass) per month during space flight.

Low bone mineral density leads to an increased risk of broken bones. If too much is lost, there is a risk of developing osteoporosis.

Astronauts in space also face decreases in blood volume and can develop increased arrhythmias.

What happens to your body when you go to space?

There are other significant effects of extended periods in space on human health. The Centre for Space Medicine at the Baylor College of Medicine notes it can have a neurological impact on astronauts.

Without gravity, the messages the brain sends to muscles and internal organs can change.

An example of this is the inner ear receiving "conflicting" inputs from the brain than what is normally expected on earth. This can result in disorientation, space motion sickness, and a general loss of sense of direction.

Astronauts have reported this makes even basic tasks difficult while in space.

For their safety, returning astronauts are usually placed in chairs to recover immediately upon arriving back on Earth.

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There are also optical side effects of being in space. Astronauts can experience vision changes, including Associate Neuro-ocular Syndrome (SANS), which causes swelling behind the eye.

Astronauts may also notice a decrease in muscle mass, so those in space perform resistive exercises to mimic lifting weights to keep strength in their arms and legs.

NASA notes astronauts have reported back pain during space flight.

What happens to your organs in space?

In the absence of gravity, the gastrointestinal system can suffer. Gravity helps move food through the GI tract and without it, the system can experience a decrease in motility.

It also makes going to the toilet quite a difficult and unpleasant task in space.

What happens to astronauts' teeth in space?

Teeth are also bones. So astronauts will experience a loss of bone mass in their teeth, too.

NASA requires oral screening procedures for potential astronauts to avoid issues including dental fillings being weakened or the loss of crowns and bridges.

Does radiation affect astronauts in space?

Humans are protected from harmful space radiation while on Earth. Astronauts, however, are at risk of being exposed to this radiation beyond Low Earth Orbit (LEO).

Prolonged exposure to radiation can result in sickness such as degenerative disease or cancer.

The shell of a spacecraft works to protect astronauts from radiation.

"Currently, the main operational countermeasure against the adverse effects of radiation is simply limiting astronaut exposure, which means limiting the amount of time astronauts are allowed to be in space," NASA notes in its report Space Faring: The Radiation Challenge.

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Is it possible to reverse the effects of prolonged space travel on the body?

Some of the effects of space travel begin to reverse after returning to Earth, including vision changes and spatial orientation, but some effects are permanent.

Cognitive performance takes some time to readjust when getting used to the Earth's gravity again.

A study in Scientific found bone density can take a long time, if ever, to return to normal.

"We've seen astronauts who had trouble walking due to weakness and lack of balance after returning from spaceflight, to others who cheerfully rode their bike on Johnson Space Center campus to meet us for a study visit," said co-author Dr Steven Boyd, a professor in the Cumming School of Medicine at the University of Calgary (UCalgary), Canada. 

"There is quite a variety of responses among astronauts when they return to Earth."

"Bone loss happens in humans—as we age, get injured, or any scenario where we can't move the body, we lose bone," explained lead author Dr Leigh Gabel, an assistant professor in the Faculty of Kinesiology, also at UCalgary.

What psychological challenges do astronauts face during space missions?

Space exploration and extended periods in space can have an adverse effect on the mental health of astronauts.

The isolation, disruption of sleep and cognitive dysfunction can cause space travellers to feel irritable and emotional while in space.

NASA notes there can be a negative psychological impact on its astronauts and is looking into how to mitigate this risk.

This includes having astronauts learn a language, examining the idea of a 'space garden' for them to tend to and providing virtual environments for exercise equipment.

Anthony Albanese has said he's open to any requests for Australia to help facilitate peace in Ukraine.

The Prime Minister's message comes as he joined world leaders in an international meeting to discuss the on-going conflict and a potential ceasefire deal.

"Australia is open to considering any requests to contribute to a future peacekeeping effort in support of the just and lasting peace we all want for Ukraine," Albanese said in a statement issued yesterday.

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"Australia is always open to considering any new proposals to support Ukraine – which we do so based on our capacity and comparative strengths."

The Coalition of the Willing virtual meeting was hosted by Albanese's British counterpart, Keir Starmer, as they urged Vladimir Putin to commit to a ceasefire deal to end the three-year war.

Ukraine's President Volodymyr Zelenskyy joined the 30 leaders from Europe, Canada and New Zealand, as well as officials from NATO and the European Union's executive.

The meeting took place in the wake of a US proposal for a 30-day ceasefire in Ukraine, which Zelenskyy has backed.

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Putin has indicated that he supports a truce in principle but has set out a host of details that need to be clarified before agreeing to a ceasefire.

During the meeting, Albanese reiterated Australia's strong and steadfast support for Ukraine and restated that Australia will stand with Ukraine "for as long as it takes".

"This is a struggle not just for the people of Ukraine and their national sovereignty. This is a struggle for the international rule of law," the Australian prime minister said.

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"President Putin's regime has imperialist designs, for Ukraine and beyond. We must ensure Russia's illegal and immoral actions are not rewarded through any peace process."

The PM added that "Australia supports all meaningful progress towards a just and enduring peace in Ukraine" but realises that "pressure will need to be applied on Russia to engage in good faith".

"We have a proud tradition of supporting peace through eighty years of contributions to international peacekeeping missions. Of course, peacekeeping missions by definition require a precondition of peace," he said.

Australia has so far committed $1.5 billion in aide to Ukraine, with $1.3 billion of that in military support, through vital equipment and training of forces.

Starmer convened the meeting, the second in two weeks, as a means of helping Ukraine in the face of a change of approach by the US, following the return of President Donald Trump, as well as gauging support for any future possible peacekeeping mission.

Many more countries were involved this time than the previous meeting on March 2.

He said there was a "stronger collective resolve and new commitments were put on the table," both in relation of the "coalition of the willing in terms of defending the deal" and also on the wider issue of the defence and security of Europe.

Without providing precise details, Starmer again said the allies were ready to put troops into Ukraine in order to safeguard the peace after any ceasefire.

The UK and France have been working to get Ukraine's allies to provide troops, weapons or other aid to a European military force that could be deployed to reassure Ukraine and deter Russia from attacking again.

"We will build up Ukraine's own defenses and armed forces, and be ready to deploy as a 'coalition of the willing' in the event of a peace deal, to help secure Ukraine on the land, at sea, and in the sky," he added.

Zelenskyy emerged from the meeting calling for strengthened sanctions to pressure Russia into accepting a ceasefire without conditions that could pave the way for a peace deal.

In a series of posts on X, he said "Moscow understands one language" and that a 30-day ceasefire "without killings" would create a window in which "it would truly be possible to negotiate all aspects of a real peace."

He also said it wasn't up to Putin who is stationed in Ukraine after any peace agreement as he gave his backing to a European contingent on the ground with an American "backstop."

"If Putin wants to bring some foreign contingent onto Russia's territory, that's his business. But it is not his business to decide anything about Ukraine's and Europe's security," Zelenskyy said.

Ukraine, under severe military pressure on parts of the front line three years after Russia's full-scale invasion, has already endorsed the truce proposal.

Russia's army has gained battlefield momentum, and analysts say Putin likely will be reluctant to rush into a ceasefire while he feels he has an advantage.

"The world is watching," Starmer said.

"My feeling is that sooner or later he is going to have to come to the table and engage in serious discussions."

– Reported with Associated Press.

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A popular tourist beach near Denmark on Western Australia's south west coast has been closed, after a snorkeller disappeared in the water more than 24 hours ago.

The search was suspended this evening and will start again tomorrow morning with police divers from Perth heading to the area.

A man in his 60s was snorkelling among the rocks at Greens Pool in William Bay near Denmark just after 4pm yesterday, when he got in distress.

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It's understood witnesses were unable to reach him before losing sight of the man.

Rescue crews were sent out but have been hampered by weather conditions and poor visibility.

9News has been told the man was visiting WA with his family.

The William Bay National Park remains closed and people are being told to avoid the area.

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One man remains on the run after two people allegedly assaulting a man with a machete during an attempted robbery in Brisbane.

Police believe a 48-year-old was inside his car, on Audrey Street in Camp Hill, about 6am today when he was approached by the pair.

The two men were allegedly armed with a machete and threatened the man, demanding his keys.

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After he refused to hand over the keys, he was allegedly assaulted by the men and suffered cuts to his arm and chest.

"I didn't have the keys on me," the victim, who didn't want to be identified, told 9News.

"And then very lucky an electrician came around the corner and basically waved them down and as that was happening, they lunged and cut through my arm and chest."

"Not very good at all, [it] needs to be stamped out very quickly."

He was taken to Princess Alexandra Hospital with non-life-threatening injuries, where he was treated and has since been released.

They left empty handed from the victim's home, fleeing the scene in a Kia Sorrento before emergency services arrived.

The Kia had allegedly been stolen from a property in Kangaroo Point overnight and was found abandoned nearby. Police confirmed the pair also stole two BMWs from a home just around the corner from the victim's.

One of the two men has since been arrested, a 21 year old man at Redcliffe.

Investigations are ongoing, and police urge anyone with dashcam footage or CCTV to contact them.

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A teenager killed in a horror off-road crash in Perth's north is being remembered as a "true blue Aussie".

Seb Foufas, 18, was crushed in the passenger seat of a Isuzu utility when the ute rolled on dirt tracks just before 11pm yesterday.

Today on Pinjar's mudflats a tragic picture is painted by tyre marks in the sand and discarded shirt left behind, along with broken glass and broken hearts.

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"I got a phone call at about 2.30 this morning and one of our other good mates goes 'oh look Jack, obviously you're best mates with him and unfortunately he's passed away'," friend Jack Jenkins told 9News.

The heavy diesel mechanic was out for a cruise when the driver lost control.

"No one deserves to die this young, but he was too good of a person to leave this earth too early," friend Shae Jenkins told 9News.

Friends today remembering Foufas as a top bloke with a heart of gold.

"He was just very top bloke, very true blue Aussie with his long mullet," Shae said.

"Never failing to make you smile, you know sometimes he'd work his 14-hour days doing a bit of overtime you know and you'd ask to see him and straight away he'd say 'yeah cool'," Jack said.

Foufas was passionate about cars and four wheel driving.

The teenager's friends say he regularly came to places like the mud flats to have fun off road.

His 19-year-old mate behind the wheel is tonight speaking with police.

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A 30-year-old man was charged today after a wild police chase through the outer suburbs of Perth earlier this week.

Matthew Ryan Allen, the driver of the allegedly stolen Mazda CX5, is tonight behind bars after being accused of 40 minutes of mayhem that put innocent drivers at risk.

"When he came back through he was just like really relaxed, sitting in his car as if he was just on a little cruise," witness, Wendy Harris, said.

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Footage supplied by the Police Air Wing showed the car driving through Warnbro, Waikiki and Rockingham about 9.20am (12.20pm AEDT) on Thursday, allegedly speeding, driving on the wrong side of the road, and running red lights.

Cars and trucks can be seen swerving out of the driver's way as he allegedly weaved through traffic, and ploughed over the median strip while being tracked by the police helicopter.

At one point the driver drives through a car wash before entering a deserted lot.

"People are coming in and out of the car wash all the time and if he'd have come through at the wrong moment, he would have just totaled somebody else off as well," Harris said.

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Rejoining the highway, the car swerved onto the shoulder of the road, hit a tree and rolled.

The driver could be seen getting out of the car and running away on foot before he was arrested nearby.

Allan was charged with stealing a car and driving recklessly, failing to stop, driving without a licence, driving with fake registration plates, and damaging property.

He was denied bail in court and remains in custody. He is set to reappear in Rockingham Magistrates Court on April 11.

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Two Kiwis to wake up much richer on Sunday morning.

An out-of-control bushfire is burning dangerously close to homes in Melbourne's east under erratic winds and heatwave conditions.

A Watch and Act warning has been issued for a fire burning through dense and dry bushland at Dr Ken Leversha Reserve in Montrose, at the foot of the Dandenong Ranges.

The Country Fire Authority urge residents in Montrose and Kilsyth to prepare to leave as gusty winds blow flames in the direction of homes to its south and east. 

KEEP UP TO DATE WITH WARNINGS HERE: https://emergency.vic.gov.au/respond/

https://twitter.com/vicemergency/status/1900773453520924704?ref_src=twsrc%5Etfw

There are homes within 50 to 100 metres of the fire in Montrose.

The bushfire ignited about 2pm today and has since burned through more than eight hectares of land.

More than 40 firefighter trucks and three helicopters are at the scene, fighting to contain the blaze. 

"Crews are basically putting the line around it and making sure that the properties on the southern and eastern side of the fire are safe," Country Fire Authority chief officer Alen Slijepcevic said.

The concern for firefighters is strong westerly winds forecast to arrive, which threaten to worsen the conditions.

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According to the Country Fire Authority, it is too early to determine how the fire started.

Temperatures reached the mid-30s in Melbourne today as a band of heat moved over several southeast states. 

Horsham hit 39 degrees. 

The entire state of Victoria was under a high fire danger warning today, with the warning to stay in place into tomorrow. 

Temperatures in Melbourne are forecast to drop to 26 degrees tomorrow with a chance of rain.

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John Birch, 39, has been identified as the body found at a paddock in Sydney's north-west as police work on a new theory surrounding his death.

Officers were searching for a missing man when they found suspected human remains under a tarp near a home in Glenorie about 11am yesterday.

Tonight, the father and friend is being remembered as a big character with an even bigger heart.

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"It's sad for anybody to have to end their life in such a tragic way," his friend Kerry Gillett told 9News.

"If he liked you, he would give you the world. If he could, if he had it, he shared it."

Police are investigating whether Birch had been run down by a ute on Gleness St about 6am yesterday.

Neighbours reported hearing a bang.

"Up on the corner of Cat Eye Ridge Road and Gleness, there was a bang early in the morning," Glenorie resident Bob said. 

Birch did not live there but regularly frequented a house about 100 metres down the road.

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That house was crawling with detectives and forensics specialists who had spent the last 24 hours collecting evidence. 

The occupants of the home, two men and a woman, were arrested yesterday and questioned overnight.

They have all since been released without charge.

While they were in custody, an unknown person tried to break into the home to search for drugs and cash. 

Investigations remain ongoing as police await the results of a post-mortem examination.

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