主页 > 国内 >

上锁的房间

NASA spacecraft launched to mysterious and rare metal asteroid_我的网站

3c认证

一 | CAPE CANAVERAL, Fla. -- NASA’s Psyche spacecraft rocketed away Friday on a six-year journey to a rare metal-covered asteroid.Most asteroids tend to be rocky or icy, and this is the first exploration of a metal world. Scientists believe it may be the battered remains of an early planet's core, and could shed light on the inaccessible centers of Earth and other rocky planets.SpaceX launched the spacecraft into an overcast midmorning sky from NASA’s Kennedy Space Center. Named for the asteroid it’s chasing, Psyche should reach the huge, potato-shaped object in 2029.“It's so thrilling,” said Laurie Leshin, director of NASA’s Jet Propulsion Laboratory. Added Arizona State University's Jim Bell, part of the Psyche team: “What a great ride so far.”An hour later, the spacecraft separated successfully from the rocket's upper stage and floated away, drawing applause from ground controllers.After decades of visiting faraway worlds of rock, ice and gas, NASA is psyched to pursue one coated in metal. Of the nine or so metal-rich asteroids discovered so far, Psyche is the biggest, orbiting the sun in the outer portion of the main asteroid belt between Mars and Jupiter alongside millions of other space rocks. It was discovered in 1852 and named after Greek mythology’s captivating goddess of the soul.“It’s long been humans’ dream to go to the metal core of our Earth. I mean, ask Jules Verne,” lead scientist Lindy Elkins-Tanton of Arizona State University said ahead of the launch. “The pressure is too high. The temperature is too high. The technology is impossible,” she said. “But there’s one way in our solar system that we can look at a metal core and that is by going to this asteroid.”Astronomers know from radar and other observations that the asteroid is big — about 144 miles (232 kilometers) across at its widest and 173 miles (280 kilometers) long. They believe it’s brimming with iron, nickel and other metals, and quite possibly silicates, with a dull, predominantly gray surface likely covered with fine metal grains from cosmic impacts.Otherwise, it’s a speck of light in the night sky, full of mystery until the spacecraft reaches it after traveling more than 2 billion miles (3.6 billion kilometers).Scientists envision spiky metal craters, huge metal cliffs and metal-encrusted eroded lava flows greenish-yellow from sulfur — “almost certain to be completely wrong,” according to Elkins-Tanton. It's also possible that trace amounts of gold, silver, platinum or iridium — iron-loving elements — could be dissolved in the asteroid's iron and nickel, she said. “There's a very good chance that it’s going to be outside of our imaginings, and that is my fondest hope," she said.Believed to be a planetary building block from the solar system’s formation 4.5 billion years ago, the asteroid can help answer such fundamental questions as how did life arise on Earth and what makes our planet habitable, according to Elkins-Tanton.On Earth, the planet's iron core is responsible for the magnetic field that shields our atmosphere and enables life.Led by Arizona State University on NASA’s behalf, the $1.2 billion mission will use a roundabout route to get to the asteroid. The van-size spacecraft with solar panels big enough to fill a tennis court will swoop past Mars for a gravity boost in 2026. Three years later, it will reach the asteroid and attempt to go into orbit around it, circling as high as 440 miles (700 kilometers) and as close as 47 miles (75 kilometers) until at least 2031.The spacecraft relies on solar electric propulsion, using xenon gas-fed thrusters and their gentle blue-glowing pulses. An experimental communication system is also along for the ride, using lasers instead of radio waves in an attempt to expand the flow of data from deep space to Earth. NASA expects the test to yield more than 10 times the amount of data, enough to transmit videos from the moon or Mars one day.The spacecraft should have soared a year ago, but was held up by delays in flight software testing attributed to poor management and other issues. The revised schedule added extra travel time. So instead of arriving at the asteroid in 2026 as originally planned, the spacecraft won’t get there until 2029.That’s the same year that another NASA spacecraft — the one that just returned asteroid samples to the Utah desert — will arrive at a different space rock as it buzzes Earth.___The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.。 8 月 25 日消息，据易车消息，广汽传祺越 7 将于 9 月 2 日正式开启预售。

二 | 据此前报道，8 月 7 日，新车已开启先享计划，199 元限时购至高价值 20000 元越 7 先享臻选权益。传祺越 7 是广汽传祺品牌首款硬派越野 SUV，新车采用当下硬派越野流行的“方盒子”车身轮廓，前脸为封闭式设计，搭配纵向排列的三颗日间行车灯。车顶前部集成激光雷达，前翼子板处配备传感器硬件，将搭载高阶辅助驾驶功能。车身尺寸方面，新车长宽高分别为 4999（选装后 5045）/2004（2030）/1933（1916）mm，轴距为 2900mm。通过性参数方面，接近角 30°、离去角 33°，高配带空气悬架版本接近角可达 33°、离去角 35°，最小离地间隙 180-270mm 可调。内饰方面，传祺越 7 搭载星河智舱 ADiGO 7.0，配备贯穿式全景星际屏，拥有 1.1 米超宽全景视野。新车配备 170mm 电动长滑轨及四六分独立座椅，进一步提升空间灵活性。座舱行业首发搭载高通 QCM8838 旗舰芯片，为智能座舱与高阶辅助驾驶提供算力支撑。动力方面，传祺越 7 搭载广汽自研“星源插混 GMC 3.0 雷霆版”系统，由 1.5T 混动发动机（最大功率 125kW）、驱动电机及 P4 后电驱组成，系统综合最大功率达 400kW，轮端扭矩可达 10000N·m。底盘采用首创的“一体化嵌入式大梁”结构，整车扭转刚度达 38000N·m/°，全系标配前后牙嵌式机械差速锁和中央能量锁（三把锁）。新车电池提供 28.3kWh、38.883kWh、45.975kWh 三种容量，对应 CLTC 纯电续航里程分别为 116km、180km 与 188km。