2.13卫星、航天飞机和空间站
Section outline
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Why are satellites important?
::为什么卫星很重要?In 1900, a category 4 devastated Galveston, Texas. It claimed the lives of between 6,000 and 12,000 people. By contrast, the death toll from Hurricane Katrina was about 1,800 people. Why the difference? Although Hurricane Katrina (and Harvey and Maria and others) was a modern tragedy, it would have been much worse without the advance warning of many weather satellites .
::1900年,德克萨斯州Galveston遭受了4类破坏,Galveston遭受了6000至12,000人的生命。相反,卡特里娜飓风造成的死亡人数约为1800人。为什么有区别?虽然卡特里娜飓风(以及哈维和玛丽亚等)是一场现代悲剧,但如果没有许多气象卫星的事先警告,情况会更糟。Rockets
::火箭火箭Humans did not reach space until the second half of the 20th century. They needed somehow to break past Earth's gravity. A rocket moves rapidly in one direction. The device is propelled by particles flying out of it at high speed in the other direction.
::人类直到20世纪下半叶才到达太空。 他们需要某种方式打破地球的引力。 火箭朝一个方向飞来飞去。 这个装置是由粒子高速从它向另一个方向飞去而推动的。How Rockets Work
::火箭如何工作Rockets were used for centuries in wars and for fireworks before anyone could explain how they worked. In 1687 Sir Isaac Newton developed his Laws of Motion. The third law says: To every action there is an equal and opposite reaction. In other words, when a rocket's propulsion pushes in one direction, the rocket moves in the opposite direction ( Figure ).
::火箭在战争和烟火中使用了几个世纪,没有人能够解释它们是如何工作的。 1687年,艾萨克·牛顿爵士制定了他的《运动法》。 第三种法律说:对于每一个行动,都有平等和相反的反应。 换句话说,当火箭的推进向一个方向推进时,火箭向相反的方向移动(图 ) 。A rocket pushes in one direction so that it moves in the opposite direction.
::一枚火箭向一个方向推进,以便向相反的方向移动。For a long time, many people believed that a rocket wouldn’t work in space. There would be nothing for the rocket to push against. But they do work! Fuel is ignited in a chamber. The gases in the chamber explode. The explosion creates pressure that forces the gases out of one side of the rocket. The rocket moves in the opposite direction ( Figure ). The force pushing the rocket is called thrust .
::长期以来,许多人认为火箭在太空是行不通的。 火箭是不会在太空发射的。 但是,火箭是不会发射的。 但是,他们确实行得通。 燃料是在一个舱室中点燃的。 室内气体爆炸。 爆炸造成了压力,迫使火箭的一边排放气体。 火箭向相反的方向移动(图 ) 。 推火箭的力量被称为推力。This Space Shuttle launch shows how the thrust of the rocket pushes the shuttle upward into the sky.
::这次航天飞机的发射表明火箭的推力是如何将航天飞机推向天空的。A Rocket Revolution
::火箭革命For centuries, rockets were powered by gunpowder or other solid fuels. These rockets could travel only short distances. Around the turn of the 20th century, liquid fuel rockets were developed. Liquid fuel gave the rockets enough power to escape Earth’s gravity. By using multiple stages, empty fuel containers could drop away. This reduced the mass of the rocket so that it could fly higher.
::几个世纪以来,火箭都是用火药或其他固体燃料来动力的。 这些火箭只能走很短的路。 在20世纪初左右,液体燃料火箭得到了开发。 液体燃料使火箭有足够的能量来躲避地球的引力。 通过使用多个阶段,空燃料容器可以下降。 这降低了火箭的重量,使其飞得更高。Satellites
::卫星卫星One of the first uses of rockets in space was to launch satellites . A satellite is an object that orbits a larger object. An orbit is a circular or elliptical path around an object. Natural objects in orbit are called natural satellites. The Moon is a natural satellite. Human-made objects in orbit are called artificial satellites.
::火箭在空间的最初用途之一是发射卫星,卫星是围绕较大物体运行的物体,轨道是围绕物体环绕的环形或椭圆路径,轨道上的自然物体称为自然卫星,月球是天然卫星,轨道上人为物体称为人造卫星。How a Satellite Stays in Orbit
::卫星如何留在轨道上Newton’s law of universal gravitation describes how an object can orbit a planet . Every object in the is attracted to every other object by gravity. Gravity also keeps you from floating away into the sky. Why doesn't gravity cause satellites to crash into Earth?
::牛顿的普遍引力法则描述了一个物体如何绕着一个行星运行。 引力吸引了所有其他物体。 引力也阻止了你漂浮在天空中。 为什么引力不导致卫星坠入地球?Newton used an example to explain how gravity makes orbiting possible. Imagine a cannonball launched from a high mountain ( Figure ). If the cannonball is launched at a slow speed, it will fall back to Earth. This is shown as paths (A) and (B). If the cannonball is launched at a fast speed, Earth curves away at the same rate that the cannonball falls. The cannonball then goes into a circular orbit, as in path (C). If the cannonball is launched even faster, it could go into an elliptical orbit (D). It might even leave Earth’s gravity and go into space (E).
::牛顿以一个例子来解释重力如何使轨道轨道成为可能。想象一下从高山(图 ) 发射的炮弹。如果炮弹以缓慢的速度发射,它就会掉回地球。这被显示为路径(A)和(B)。如果炮弹以快速速度发射,地球曲线就会以与炮弹弹落速度相同的速度移动。炮弹随后进入环绕轨道,就像在路径(C)一样。如果炮弹发射得更快,它可能进入椭圆轨道(D)。它甚至可能离开地球的引力,进入空间(E)。Isaac Newton explained how a cannonball fired from a high point with enough speed could orbit Earth.
::Isaaac Newton解释了一枚炮弹如何以足够快的速度从高点发射到地球轨道。Unfortunately, Newton’s idea would not work in real life. A cannonball launched at a fast speed from Mt. Everest would burn up in the atmosphere . However, a rocket can launch straight up, then steer into orbit. It won't burn up in the atmosphere. So a rocket can carry a satellite above the atmosphere and then release the satellite into orbit.
::不幸的是,牛顿的想法在现实生活中行不通。 从珠穆朗玛峰快速发射的炮弹会在大气中燃烧。 然而,火箭可以直接发射,然后飞入轨道。 它不会在大气中燃烧。 因此,火箭可以在大气层上携带卫星,然后将卫星释放到轨道上。Satellite Orbits
::卫星轨道Satellites have different views depending on their orbit. Satellites may be put in a low orbit. These satellites orbit from north to south over the poles. These satellites view a different part of Earth each time they circle. Imaging and weather satellites need this type of view.
::卫星视轨道的不同而有不同的观点,卫星可置于低轨道上,这些卫星从北向南在极上方轨道上运行,这些卫星每次绕圈时都观测地球的不同部分,成像卫星和气象卫星需要这种视角。Satellites may be placed so that they orbit at the same rate the Earth spins. The satellite then remains over the same on the surface. Communications satellites are often placed in these orbits.
::卫星可被放置,以便以地球旋转的相同速度运行,卫星在地面上仍然处于同样的轨道上,通信卫星往往被放置在这些轨道上。Types of Satellites
::卫星类型类型The first artificial satellite was launched just over 50 years ago. Thousands are now in orbit around Earth. Satellites also orbit the Moon, the , , , , and . Satellites have many different purposes. There are satellites for communications and navigation. There are satellites for taking pictures of a planet's surface.
::第一颗人造卫星是50多年前发射的,数千颗卫星现已在环绕地球的轨道上运行,卫星还绕月球、月球、卫星、卫星和卫星运行,卫星有许多不同的目的,有卫星用于通信和导航,有卫星用于拍摄行星表面。Dozens of satellites collect data about Earth. NASA’s Landsat satellites make detailed images of Earth’s continents and coastal areas. Other satellites study the oceans, atmosphere, polar ice sheets, and other Earth systems. This data helps us to monitor climate change. Other long-term changes in the planet are also best seen from space. Satellite images help scientists understand how Earth’s systems affect one another. Different satellites monitor different wavelengths of energy .
::数十颗卫星收集了关于地球的数据。美国航天局的大地卫星对地球大陆和沿海地区做了详细的图像。其他卫星研究海洋、大气、极地冰盖和其他地球系统。这些数据帮助我们监测气候变化。地球的其他长期变化也最好从空间观察。卫星图像有助于科学家了解地球系统如何相互影响。不同的卫星监测不同的能量波长。Space Stations
::空间站Humans have a presence in space at the International Space Station (ISS) ( Figure ). Modern space stations are constructed piece by piece to create a modular system. The primary purpose of the ISS is scientific research, especially in medicine, biology, and physics.
::人类在国际空间站有空间存在(图......),现代空间站是用一个模块系统逐件建造的,其主要目的是科学研究,特别是医学、生物学和物理学方面的科学研究。A photograph of the International Space Station was taken from the space shuttle Atlantis in June 2007.
::2007年6月,从亚特兰蒂斯航天飞机拍摄了国际空间站的照片。Space Shuttles
::航天飞机Craft designed for human spaceflight, like the Apollo missions, were very successful. They were also very expensive and could not carry much cargo. They could be used only once. To outfit the ISS, NASA needed a space vehicle that was reusable. It needed to be able to carry large pieces of equipment. The cargo might include satellites, space , or sections of a space station. The resulting spacecraft is called a space shuttle ( Figure ).
::与阿波罗飞行任务一样,为载人航天飞行设计的手工艺非常成功,也非常昂贵,无法运载大量货物,只能使用一次。为了装备国际空间站,美国航天局需要一台可再使用的航天器,需要能够运载大量设备。货物可能包括卫星、空间或空间站的部分。由此产生的航天器被称为航天飞机(图 )。Atlantis on the launch pad in 2006. Since 1981, the space shuttle has been the United States’ primary vehicle for carrying people and large equipment into space.
::自1981年以来,航天飞机一直是美国载人和大型设备进入太空的主要载体。A space shuttle has three main parts. The part you are probably most familiar with is the orbiter . The orbiter has wings like an airplane. When a space shuttle launches, the orbiter is attached to a huge fuel tank that contains liquid fuel. On the sides of the fuel tank are two large "booster rockets." All of this is needed to get the orbiter out of Earth’s atmosphere. Once in space, the orbiter can be used to release equipment (such as a satellite or supplies for the International Space Station). It can be used to repair existing equipment, such as the Hubble Space Telescope . Astronauts can even do experiments directly on board the orbiter.
::航天飞机有三个主要部件。 您可能最熟悉的部分是轨道器。 轨道器有像飞机一样的翅膀。 当航天飞机发射时, 轨道器被附在装有液体燃料的巨型燃料箱上。 在燃料箱的两侧是两枚大型的“ 推进火箭 ” 。 所有这一切都是为了让轨道器离开地球大气层。 一旦进入太空, 轨道器就可以用来释放设备( 如卫星或国际空间站的供应) 。 它可以用来修理现有的设备, 如哈勃空间望远镜。 宇航员甚至可以在轨道器上直接进行实验。When the mission is complete, the orbiter re-enters Earth’s atmosphere. The craft flies back to Earth more like a glider than an airplane. The Space Shuttle program did 135 missions between 1981 and 2011, when the remaining shuttles were retired. Since the space shuttles have retired, the ISS is serviced by Russian Soyuz spacecraft.
::当飞行任务完成时,轨道器重新进入地球大气层。飞行器飞回地球时更像滑翔机而不是飞机。1981年至2011年期间,航天飞机计划完成了135次飞行任务,而当时剩下的航天飞机已经退役。 自从航天飞机退役以来,国际空间站由俄罗斯联盟航天器提供维修服务。You can visit the retired shuttles around the country:
::您可访问全国各地的退休穿梭飞机:- Enterprise at the Intrepid Sea-Air-Space Museum, New York City.
::纽约市因诺琴蒂海空空间博物馆企业。
- Discovery at the National Air and Space Museum, Chantilly Virginia.
::在Chantilly Virginia国家航空和空间博物馆发现
- Atlantis at the Kennedy Space Center, Florida.
::佛罗里达肯尼迪太空中心的亚特兰蒂斯
- Endeavour at the California Science Center, Los Angeles.
::努力在洛杉矶加州科学中心工作
SpaceX
::SpaceXOn May 30, 2020 NASA and SpaceX sent Robert Behnken and Douglas Hurley to the International Space Station from the Kennedy Space Center in Florida. These astronauts were testing SpaceX’s Falcon 9 rocket and Crew Dragon spacecraft on their ability to transport people to and from the International Space Station.
::2020年5月30日,美国航天局和宇宙航空研究开发公司(SpaceX)将罗伯特·贝肯和道格拉斯·赫尔利送至佛罗里达肯尼迪航天中心的国际空间站。 这些宇航员正在测试太空船的“猎鹰9号”火箭和“龙轮”号航天器,以测试他们运送人员往返国际空间站的能力。This illustration shows the Crew Dragon spacecraft in low Earth orbit.
::本图展示了低地球轨道上的 " 龙船 " 航天器。This historic launch is the first commercially built spacecraft to take astronauts into Earth’s orbit. It is also the first time in the United States launched its astronauts from US soil since NASA’s Space Shuttle Program ended in 2011. Falcon 9 is also the first rocket that can send things into Earth’s orbit and then be reused for another flight.
::这次历史性的发射是第一个将宇航员带入地球轨道的商业建造的航天器。 这也是美国自美国航天局航天飞机方案于2011年结束以来首次从美国土壤中发射宇航员。 猎鹰9号也是第一枚能够将物体送入地球轨道,然后再用于另一场飞行的火箭。These amazing firsts all contribute to NASA’s Commercial Crew Program which partners NASA with private companies to build space transport systems to make space travel and research cheaper and more effective.
::这些令人惊异的先锋都为美国航天局的商业机组人员方案做出了贡献,该方案与美国航天局和私营公司合作,建设空间运输系统,使空间旅行和研究更便宜、更有效。Science Friday: How A LEGO Shuttle Got To Space
::科学星期五:GEGO航天飞机如何进入太空How would you get a LEGO shuttle to space? In this video by Science Friday, Raul Oaida, 18-years-old, attached a LEGO shuttle, a video camera and a GPS tracker, to a huge helium balloon and sent them into space. The shuttle reached an altitude of 115,000 feet before heading back to Earth.
::如何让LEGO航天飞机飞到太空?在这段视频中,18岁的Laul Oaida科学星期五将LEGO航天飞机、摄像头和全球定位系统跟踪器附在一个巨大的氦气球上并将其送入太空。该航天飞机在返回地球之前达到115,000英尺的高度。Summary
::摘要- Rockets are propelled into space by particles flying out one end at high speed. This allows them to escape gravity.
::火箭被粒子以高速从一端飞出,推入太空,这样它们就能够逃脱引力。
- Thousands of artificial satellites orbit Earth. Satellites are used for imaging, communications, navigation, and human habitation.
::卫星用于成像、通信、导航和人类居住。
- Space stations are continuously inhabited by humans. The humans reach the space station by space shuttle.
::空间站不断有人类居住,人类乘航天飞机到达空间站。
Review
::回顾- How does a rocket work?
::火箭怎么用?
- Why are there so many satellites orbiting Earth at this time?
::为什么现在有这么多卫星环绕地球运行?
- How do artificial satellites stay in orbit? Is this how natural satellites, like the Moon, stay in orbit?
::人造卫星如何留在轨道上?像月球一样,自然卫星如何留在轨道上?
Explore More
::探索更多Use the resources below to answer the questions that follow.
::利用以下资源回答以下问题。- How do scientists study Earth from space?
::科学家如何从空间研究地球?
- What does the Aqua satellite do?
::Aqua卫星是做什么的?
- What does the Terra satellite do?
::Terra卫星是做什么的?
- What is Landsat?
::什么是大地卫星?
- Why is it important?
::为什么这很重要?
- What has been learned from Landsat images?
::从Landsat图像中学到了什么?
Science Friday: How A LEGO Shuttle Got To Space
::科学星期五:GEGO航天飞机如何进入太空How would you get a LEGO shuttle to space? In this video by Science Friday, Raul Oaida, 18-years-old, attached a LEGO shuttle, a video camera and a GPS tracker, to a huge helium balloon and sent them into space. The shuttle reached an altitude of 115,000 feet before heading back to Earth.
::如何让LEGO航天飞机飞到太空?在这段视频中,18岁的Laul Oaida科学星期五将LEGO航天飞机、摄像头和全球定位系统跟踪器附在一个巨大的氦气球上并将其送入太空。该航天飞机在返回地球之前达到115,000英尺的高度。 - Enterprise at the Intrepid Sea-Air-Space Museum, New York City.
