太空船嘗試有史以來最接近太陽

NASA is making headlines with its Parker Solar Probe, which is on a mission to achieve the closest-ever approach to the Sun. This spacecraft is currently diving into the Sun's outer atmosphere, a region known for its extreme heat and intense radiation. During this daring fly-by, the Parker Solar Probe will be out of communication with Earth for several days, leaving scientists anxiously awaiting a signal that is expected to arrive at 05:00 GMT on December 28. The primary goal of this mission is to enhance our understanding of the Sun and its complex behavior. Dr. Nicola Fox, the head of science at NASA, expressed her excitement about the mission, stating, 'For centuries, people have studied the Sun, but you don't experience the atmosphere of a place until you actually go visit it. ' This highlights the importance of direct exploration in gaining insights into the Sun's atmosphere. The Parker Solar Probe was launched in 2018 and has already completed 21 orbits around the Sun, gradually getting closer with each pass. However, the upcoming Christmas Eve visit is particularly significant as it will set a new record. At its closest point, the probe will be just 3. 8 million miles away from the Sun's surface. While this distance may seem vast, Dr. Fox provided a relatable analogy: 'We are 93 million miles away from the Sun, so if I put the Sun and the Earth one meter apart, Parker Solar Probe is four centimeters from the Sun - so that's close. ' The spacecraft will face extreme conditions, including temperatures reaching 1,400 degrees Celsius and radiation levels that could potentially damage its onboard electronics. To protect itself, the Parker Solar Probe is equipped with a robust shield made of carbon-composite material that is 11. 5 centimeters thick. The spacecraft's strategy is to make quick passes, moving at an astonishing speed of 430,000 miles per hour. This speed is equivalent to traveling from London to New York in less than 30 seconds! The Parker Solar Probe's incredible velocity is a result of the immense gravitational pull it experiences as it approaches the Sun. One of the key scientific questions that the mission aims to address is the mystery of why the Sun's outer atmosphere, known as the corona, is so much hotter than its surface. Dr. Jenifer Millard, an astronomer, explained, 'The surface of the Sun is about 6,000 degrees Celsius, but the corona, this tenuous outer atmosphere that you can see during solar eclipses, reaches millions of degrees - and that is further away from the Sun. So how is that atmosphere getting hotter? ' The mission will also provide valuable insights into solar wind, which is a continuous stream of charged particles emitted from the corona. When these particles interact with the Earth's magnetic field, they create stunning auroras in the sky. However, this space weather can also pose challenges, such as disrupting power grids and communication systems. Dr. Millard emphasized the significance of understanding the Sun's activity, stating, 'Understanding the Sun, its activity, space weather, the solar wind, is so important to our everyday lives on Earth. ' As the Parker Solar Probe remains out of contact with Earth, NASA scientists are filled with anticipation. Dr. Fox mentioned that once they receive a signal from the probe, the team will send her a text with a green heart emoji to confirm that the spacecraft is safe. She admitted to feeling nervous about this ambitious mission, but she has confidence in the probe's design. 'I will worry about the spacecraft. But we really have designed it to withstand all of these brutal, brutal conditions. It's a tough, tough little spacecraft. ' If the Parker Solar Probe successfully navigates this challenging phase, it will continue its groundbreaking mission around the Sun in the years to come.