“阿里安”火箭1995年月均一发

阿里安空间公司最近公布“阿里安”运载火箭１９９５年的发射计划如下：１．１月，发射欧空局的第二颗地球资源卫星ＥＲＳ－２。２．２月，发射国际通信卫星－７０６。３．３月，发射美国休斯公司的第三颗直接广播卫星ＤＢＳ－３。４．３月，发射法国第一颗军事侦察卫星太阳神－１。５．４月，发射日本电报电话公司（ＮＴＴ）的“Ｎ－星”卫星。６．５月，发射泛美卫星公司的ＰＡＳ－４卫星和以色列Ｓｐａｃｅｃｏｍ卫星通信公司的Ａｍｏｓ卫星。７．６月，发射卢森堡ＳＥＳ公司的Ａｓｔｒａ－１Ｅ卫星。８．８月，发射法国电信公司（Ｔｅｌ…     

Influence of ionic inorganic solutes on self-assembly and polymerization processes related to early forms of life: implications for a prebiotic aqueous medium

A commonly accepted view is that life began in a marine environment, which would imply the presence of inorganic ions such as Na+, Cl-, Mg2+, Ca2+, and Fe2+. We have investigated two processes relevant to the origin of life--membrane self-assembly and RNA polymerization--and established that both are adversely affected by ionic solute concentrations much lower than those of contemporary oceans. In particular, monocarboxylic acid vesicles, which are plausible models of primitive membrane systems, are completely disrupted by low concentrations of divalent cations, such as magnesium and calcium, and by high sodium chloride concentrations as well. Similarly, a nonenzymatic, nontemplated polymerization of activated RNA monomers in ice/eutectic phases (in a solution of low initial ionic strength) yields oligomers with > 80% of the original monomers incorporated, but polymerization in initially higher ionic strength aqueous solutions is markedly inhibited. These observations suggest that cellular life may not have begun in a marine environment because the abundance of ionic inorganic solutes would have significantly inhibited the chemical and physical processes that lead to self-assembly of more complex molecular systems.     

欧洲人士鼓吹欧空局接受军事任务

欧洲空间局历来是以发展为和平利用外层空间的航天技术为己任的。但近年来，由于民用空间任务经费削减，军事空间任务前景看好，军事和民用部门都希望尽量节省空间支出，因此，在今后的年代里，欧空局有望接受军事空间任务。一些欧洲的政府官员预测，欧空局最终将成为欧洲联盟的两用空间研究组织，既向民用部门，也向军事部门提供卫星技术。欧空局已经同西欧联盟签订了正式的合同，正在成为欧盟的防御力量。欧盟正日益重视从空间进行战略观察的任务。欧空局局长Ｌｕｔｏｎ认为，欧空局的章程并不影响它接受军事部门的地球观察卫星任务。“虽…     

卫星装点未来

３０多年前，当第一颗通信卫星发射时，谁能预见到后来的巨大进展？卫星从来没有像今天那样在改善世界通信和全球信息业务方面，拥有灿烂的前景。我相信，今后的１０年将比过去的３０年更加辉煌。我个人对未来发展的设想是，今后１０年内，卫星系统将会像“信息自动售货机...     

NASA局空地通信系统商业化的设想与机遇

１９９５年１１月美国航空航天局（ＮＡＳＡ）负责空间通信的副局长指示哥达德航天中心采办通信业务，该业务“等同”于当前由ＮＡＳＡ拥有的深空网２６米子网所提供的业务，并且在１９９７年９月３０日办完。作者领导一个小组利用以性能为基础的固定价格合同法完成了这一项任务。这种方法采取了一些新措施，以简化评估过程。这项工作以１９９６年３月向工业界发布求购草案而结束。此后不久，哥达德航天中心发布了一份为对地观测系统     

Haze aerosols in the atmosphere of early Earth: manna from heaven

An organic haze layer in the upper atmosphere of Titan plays a crucial role in the atmospheric composition and climate of that moon. Such a haze layer may also have existed on the early Earth, providing an ultraviolet shield for greenhouse gases needed to warm the planet enough for life to arise and evolve. Despite the implications of such a haze layer, little is known about the organic material produced under early Earth conditions when both CO(2) and CH(4) may have been abundant in the atmosphere. For the first time, we experimentally demonstrate that organic haze can be generated in different CH(4)/CO(2) ratios. Here, we show that haze aerosols are able to form at CH(4) mixing ratios of 1,000 ppmv, a level likely to be present on early Earth. In addition, we find that organic hazes will form at C/O ratios as low as 0.6, which is lower than the predicted value of unity. We also show that as the C/O ratio decreases, the organic particles produced are more oxidized and contain biologically labile compounds. After life arose, the haze may thus have provided food for biota.     

德国可能大幅度增加航天预算

据巴黎的观察家们分析，德国政府经过多年的犹豫不决之后，终于决定在今后１０年（１９９５～２００４年）内，为发展航天技术投资１００亿马克（６５亿美元），并将发展军用航天技术。据称，这个计划是由德国总理办公室作出的，但能否生效还有待于德国的大选。只要科尔继续当选总理，此项决定将会在年底宣布。法国一位高级官员认为，德国介入军用航天是欧洲的一个重大事件。自德意志立宪法庭批准德国的维和部队可以进驻北大西洋公约集团以外的地区之后，德国政府日益感到，它需要通信卫星和观测卫星来支持其部队，而不能仅仅依赖其他国家的…     

欧盟支持建立全欧侦察卫星系统

６月２０日，西欧联盟议员在巴黎开会。会议建议，欧盟应参加以法国为首的侦察卫星计划。欧盟建议将大阳神－２光学侦察卫星及其后续的“Ｈｏｒｕｓ”雷达卫星纳入该组织的泛欧计划。该计划应先以法德联合计划的形式起步，然后逐步扩大到欧盟的其他成员国。德国外文部长金克尔在会议上发言，主张欧洲必须建立自己的侦察卫星第统，下一代侦察工呈的费用应当由欧盟全体成员国共同承担。他呼吁欧盟各成员对太阳种－２计划提供财政支持。欧洲侦察卫星系统将从法、德两国为核心。该系统的第一颗卫星太阳神－１Ａ于今年７月７日发射；第二颗卫星大…