A Nasa spacecraft is attempting to make history with the closest-ever approach to the Sun.
The Parker Solar Probe is plunging into our star’s outer atmosphere, enduring brutal temperatures and extreme radiation.
It is out of communication for several days during this burning hot fly-by and scientists will be waiting for a signal, expected at 05:00 GMT on 28 December, to see if it has survived.
The hope is the probe could help us to better understand how the Sun works.
According to Dr Nicola Fox, head of science at Nasa “For centuries, people have studied the Sun, but you don’t experience the atmosphere of a place until you actually go visit it.
It has already swept past the Sun 21 times, getting ever nearer, but the Christmas Eve visit is record-breaking.
At its closest approach, the probe is 3.8 million miles (6.2 million km) from our star’s surface.
This might not sound that close, but Nasa’s Nicola Fox puts it into perspective: “We are 93 million miles away from the Sun, so if I put the Sun and the Earth one metre apart, Parker Solar Probe is four centimetres from the Sun – so that’s close.”
The probe will have to endure temperatures of 1,400C and radiation that could frazzle the onboard electronics.
It is protected by a 11.5cm (4.5 inches) thick carbon-composite shield but the spacecraft’s tactic is to get in and out fast.
In fact, it will be moving faster than any human-made object, hurtling at 430,000mph – the equivalent of flying from London to New York in less than 30 seconds.
Parker’s speed comes from the immense gravitational pull it feels as it falls towards the Sun.
