航天飞机发射倒计时

在肯尼迪航天中心发射场,有一个历史悠久的倒计时钟,它自1968年阿波罗计划开始一直服役至今,每次都出现在航天飞机点火升空前的画面中。它使用老式白炽灯泡打出数字轮廓,如今已饱经风霜,全身有明显的磨损痕迹。用现在流行的一句话来说:"用倒计时来倒计时",经历过成功和悲剧,     

从发现号航天飞机的安全谈空间碎片的危害

2005年8月9日，发现号航天飞机在执行完14天的太空飞行任务后，安全返回美国爱德华兹空军基地。此次飞行是哥伦比亚号航天飞机失事后的首次飞行。虽然在此前两年半的时间里美国航宇局（NASA）耗资30多亿美元，在六个方面改善了航天飞机的性能，但整个过程并不顺利，可谓一波三折，引起了全世界的广泛关注。让美国人引以自豪的航天飞机日显老态，逐渐暴露出诸多问题，这对美国今后的航天事业也将产生深远的影响。     

Assessing the legacy of the Space Shuttle

This article reviews the core legacies of the Space Shuttle program after 25 years and suggests that, while it was not an unadulterated success, on balance the Shuttle served a valuable role in the development of spaceflight and deserves an overall positive assessment in history. There are five core legacies that deserve discussion. First, the Space Shuttle has a reputation as a mistake resulting from a policy failure that should never have been pursued. Second, it has been criticized as a program that prohibited other paths for the US space program. Third, and more positively, the Space Shuttle provided more than two decades of significant human spaceflight capability and stretched the nature of what could be accomplished in Earth orbit much beyond where it had previously been. Fourth, it served as a relatively flexible platform for scientific activities. Finally, and perhaps most significantly since the US human spaceflight program has always been focused on national prestige, the Space Shuttle served well as a symbol of American technological verisimilitude.     

航天飞机上的食品装备

在太空,航天员们也同在地球上一样,离不开一日三餐。那些专供航天飞机乘组成员的各类食品也并不神秘,都是在地球上事先装载准备好的,一些食品甚至可以在商店、超市的货架上购买到。     

“发现”号航天飞机小传

1983年10月,美国第三架航天飞机"发现"号正式完工出厂;11月,正式加入航天飞机队伍。从此时起,"发现"号开始来往于天地之间,前后共成功完成了近40次太空飞行任务,超过了航天飞机队伍中的其他任意一架。在NASA专家的眼中,"发现"号是美国航天飞机队伍中最值得信任的一架。     

A reappraisal of the Space Shuttle programme

The conventional wisdom holds that the Space Shuttle programme has been a ‘policy failure’ because NASA compromised its original concept in the face of weak political commitment and inadequate funding. However, a detailed reappraisal of the history shows that this reasoning is ambiguous, counterfactual and contrary to experience. Congressional and presidential support for the Shuttle has consistently been generous despite flawed and shifting justifications for the programme advanced by NASA. Among the lessons to be learned are the need for more rigorous congressional oversight and the development of smaller, quicker and independent civil space programmes.     

The decision to develop the Space Shuttle

Many of the problems that the Space Shuttle programme has had in meeting its goals of routine and cost-effective access to space can be traced to various characteristics of the decision to develop the Space Shuttle. That decision was made through a process of bureaucratic politics, with little attention given to future users of the Shuttle. The design chosen for development was a poor compromise between demanding Pentagon and NASA requirements and a limited budget.     

航天飞机自动着陆技术概念研究

自动着陆段是航天飞机整个飞行任务的最后一段 ,它是指从离地高度 30 0 0m的自动着陆入口到航天飞机在跑道上着陆滑跑的这一段飞行。在自动着陆段 ,航天飞机着陆采用对基准轨迹跟踪的方式 ,就是根据预先设计好的基准轨迹 ,各模态的制导系统将航天飞机的高度误差和高度速率误差按照一定制导律得出法向加速度指令 ,去控制飞机 ,以跟踪基准轨迹。本文还阐述了速度控制、起落架着地后的俯仰速率控制、横滚改出及飞行员人工监控和接管航天飞机着陆等内容。自动着陆技术的概念研究为以后航天飞机自动着陆系统的开发提供了必要的设计思想与工程实现手段     

Study of vibration microaccelerations onboard the International Space Station

The results of studying vibration microaccelerations aboard the International Space Station are presented. The study was performed using the measurement data of the MAMS low-frequency and the SAMS high-frequency accelerometers. For the study, six intervals of measurements were selected, performed in 2005. During these intervals the station was flying in the standard orbital orientation, attitude control engines were not switched on, and the crew rested. Discrete and continuous spectra were analyzed on selected intervals. The most significant disturbances with the discrete spectrum (cyclic trends) have been found. Using the second order autoregression model, parameters of the most significant disturbances with the continuous spectrum were determined. This study was carried out as a part of the technical experiment “The ISS environment”.     

美发射军用航天飞机试验机

<正>在由NASA提出方案10多年后,现属美国空军项目的一种无人军用航天飞机试验机4月22日由一枚宇宙神5/501型火箭从卡纳维拉尔角空军站发射升     

航天飞机先进固体火箭发动机的推进剂

综述了美国航天飞机走进固体火箭发动机的推进剂配方研制，制造工艺和工艺过程中的质量控制。     

Attached payloads on SPACEHAB, growing from the Space Shuttle to the Space Station

Although NASA's Space Shuttle is largely dedicated in the near term to Space Station assembly, 10–16 day flight opportunities still abound for spacecraft technology demonstration payloads, and experiments for the established earth and space science communities. This paper will present the latest developments of SPACEHAB flight systems in order to accommodate the flight needs of these communities on the Space Shuttle today and the Space Station tomorrow. In particular, some examples of payloads from these disciplines will be introduced together with the accommodation and experiment objectives.     

Determination of the Microacceleration Quasisteady Component onboard the International Space Station

A comparison of two methods of determination of the microacceleration quasisteady component arising onboard the International Space Station was performed. In the first method the acceleration was calculated using the relative motion of the station reconstructed on the basis of telemetry data. The second method was a direct measurement of the microacceleration by a low-frequency accelerometer and a smoothing of the data obtained. The used measurements were made by the American accelerometer MAMS. The above comparison can theoretically be used to refine the position of the station center of mass relative to its body.     

美国航天飞机故障一览

美国航天飞机在22年的飞行中曾发生过大大小小的故障无数起。挑战者号和哥伦比亚号悲剧只是这些故障的最高“体现。这里我们有选择地把美国航天飞机此前发生的各类故障罗列于此，不难看出偶然出现的飞行灾难其实有其必然性。     

2010航天飞机第一次飞行

<正>2010年1月6日,奋进号航天飞机被送上位于佛罗里达州的肯尼迪航天中心的发射台,预计于美国东部时间2010年2月上旬凌晨发射,执行STS-130任务。如果一切能按计划顺利进行的话,这将是美国航天飞机退役前的最后一次夜间发射任务。     

Relative efficacy of the proposed Space Shuttle antimotion sickness medications

Space motion sickness has been estimated as affecting between 1/3 and 1/2 of all space flight participants. NASA has at the moment proposed a combination of promethazine and ephedrine (P/E) and one of scopolamine and dextroamphetamine (S/D), both given orally, as well as a transdermally applied scopolamine (TAS), as preventive and ameliorative measures. The reported double-blind study, tests the early phase actions and efficacy of the transdermal scopolamine (Transderm (TM)-V of ALZA Corporation) and compares these in detail to the oral medications. Motion sickness resistance was tested by standardized head movements while accelerating at 0.2 degree/sec2 to a maximum rotation of 240 degrees/sec, with an intermediate plateau of 10 min at 180 degrees/sec. To permit weighting motion sickness protection against other system influences, cardiovascular, psychological (subjective and objective), and visual parameter changes were documented for the three therapeutic modes. The relative impact of the various modalities on operational and experimental components of space missions is discussed. A comparison to intramuscularly administered promethazine (a backup therapeutic mode suggested for Space Shuttle use) is also included.     

美国航天飞机商业化的若干问题

航天飞机是一种能够运送人类往返于外层空间和大气空间的特殊运载工具，具有兼顾军用和民用并且造价昂贵的特点。美国是目前世界上唯一拥有这一运载工具的国家。从航天飞机的背景来看，它虽然是美国和苏联在冷战时期进行技术竞赛所带来的空间成就，但     

Survey of mission evolution and flexibility in the Space Shuttle program

Given the diversity of missions it has accomplished and the myriad of adaptations it has undergone, the US Space Shuttle is widely regarded as a highly flexible space vehicle. With the Shuttle’s upcoming 2011 retirement, it is instructive to survey the history of this vehicle’s flexibility for the insights it can provide to the design and characterization of flexibility in future space systems. Data are presented on the evolution of mission requirements over time for 120 missions performed by the Space Shuttle over a period of some 27 years. Distinct trends in the time domain – as well as their causes – are identified and discussed, and early manifest plans from 1982 serve as a confirmation that these trends were not originally anticipated. Eight examples are then presented of engineering modifications that allowed the Shuttle to adapt and accommodate these requirement changes. Several additional instances of Shuttle flexibility are explored, such as post-Columbia disaster modification, upgrade programs and derived vehicles, and one case in which flexibility was inhibited by an early design decision.