朝鲜的Teapodong-2 Unha导弹发射：我们会学到什么？

适应症朝鲜计划推出的导弹，目的是将卫星放入轨道上。朝鲜人正在用纯粹无害的平民术语描绘发射，甚至命名了韩国人的“银河系”，以强调其面向太空的功能。在西方，火箭被称为Taepodong-2被认为是远程（但不是真正的洲际范围）弹道导弹。

即使火箭发射了卫星，最近的新闻报道ReportsReports假设有效载荷部分似乎是卫星的形状和大小，这将是他们军事弹道导弹计划的重要一步。在苏联和美国太空计划的早期，军事和平民火箭发展之间几乎没有区别，而朝鲜即将推出的发射也是如此。我想在本文中讨论的问题是，外界可以学到多少朝鲜测试是否经历了多少，它告诉我们他们的弹道导弹能力是什么？

According to the朝鲜陈述，夸蒙兴（Kwangmyongsong-2）或明亮的星光灯光，卫星是一颗通信卫星。当然，这是透明的荒谬。大多数通信卫星都在地球同步轨道上，远远超出了朝鲜人的范围。在低地轨道上的一颗卫星将不是一个有用的通信卫星，我不相信任何人都希望朝鲜人推出整个卫星。也许“通信卫星”的意思是，卫星将与我们交流，而不是被人们用来互动。根据朝鲜的说法，他们的最后一颗卫星于1998年8月发射，绕地球绕着地球绕着“不朽的革命”曲调，“金正恩将军的歌”。（这与称呼，夸米龙或明亮的星光或明亮的洛德星，是金正恩无数的sobriquets之一。）实际上，这种卫星实际上从未存在。来自朝鲜ReportsReports以外的所有报道称，火箭的最后阶段爆炸，破坏了卫星。美国太空司令部从未跟踪任何可能是朝鲜卫星的物体，也没有发现太空的传播。（有一个音乐先例：第一个中国卫星，它具有明显的区别，即实际进入轨道，传递了曲调：“The East Is Red。”）

1998年发布的发射将陶波多1导弹作为太空发射车（SLV）。Taepodong-1由鼻子导弹组成，作为第一阶段，将Hwasong-6导弹作为第二阶段。（我们应该记住，一些朝鲜导弹，例如鼻子和Hwasong-6，已经生产了数量，甚至是出口，因此它们的特征很好。陶波多奇是不同的，它们从未成功地测试流动，并且它们是从其他组件组合在一起。我有点不舒服地将它们的名称分配好，好像它们是生产导弹；在这个阶段，每个人都可能一次一次。我们将看到。）在1998年的飞行中，增加了第三阶段以提升小卫星进入轨道。正是第三阶段显然失败了，因此朝鲜可能会获得有关前两个阶段表现的大量和重要数据，而这本来可以构成军事弹道导弹的两个阶段。

The Taepodong-2 was tested only once in 2006 and exploded about 40 seconds into its flight and it seems this upcoming launch is a retry of that failed test. The first stage of the Taepodong-2 appears similar to the Chinese CSS-2 missile. David Wright speculates that the first stage will have four Nodong engines operating together. A single Nodong serves as the second stage. The North Koreans have declared warning zones where the first and second stages are expected to impact.大卫·赖特（David Wright）和Geoffrey Forden已经从宣布的溅落区域中向后工作，以查看它们是否与Taepodong-2的假定配置一致，并结帐。

如果朝鲜人不参加这项测试，那对世界会更好（也许最好的结果是火箭炸毁了几秒钟的飞行测试 - 我们总是可以希望），但是如果他们进行测试，世界其他地方可能会尽可能多地学习它，我们可以学到很多东西。
该导弹正在从SLV期望的那种发射台上发射。它正在公开场合组装，朝鲜人没有努力隐藏导弹。媒体发布了一些低分辨率的图像，但是美国和其他人的照片是可以拍摄更高分辨率图像的照片，也许可以看到细节降至几厘米。可以想象的是，美国和其他人也足够大胆，可以在附近驾驶无人机，以拍摄更详细的照片。但是，除非无人机被击落，否则不要指望任何一方都有任何公开宣布。因此，尽管我们在外面推测导弹的大小和形状是什么，但国家情报部门已经知道，在导弹飞行之前。

该导弹将由雷达跟踪 - 美国人和日本人在该地区有雷达船，韩国和日本将具有基于地面的雷达 - 这将提供导弹轨迹的详细，即时的逐局记录。这允许计算加速度，从而使我们能够计算推力与火箭的重量的比率。如果我们知道其中一个，那么我们就可以计算另一个，我们将找到确定重量的方法。

火箭将加速加速，加速度的速度会增加，因为发动机的推力保持恒定（一些更先进的火箭会随着发动机的限制而花哨的东西，但是朝鲜人可能还没有）一直在燃烧燃料。因此，我们不知道火箭，推力或燃油流的重量，但是我们可以找出所有比率和一些未知数在方程式中取消的。通过看到加速度变化的速度，我们可以找出火箭技术最重要的措施之一，即特定的冲动。特定的冲动是给定燃料量提供的“冲动”或总推动（技术上的动量变化）的数量。它以牛顿秒/千克或英语单位为磅/磅进行测量。（一些美国工程​​师取消分子中的力量和分母中的质量磅，并以几秒钟的单位报告特定的冲动，这会使任何好的物理学家哭泣。相信我，我会收到很多信件，以解释我的方式totally wrong and don’t understand specific impulse.) The specific impulse depends on the type of fuel, the efficiency of the combustion, and the maximum temperatures and pressures that the rocket engine can stand, all things that are technical challenges, making specific impulse a good measure of overall technical sophistication of a rocket builder.

Keep in mind that, for long-range rockets, the initial weight of the fuel is about 90% of the total weight, the structure—the tanks, engines, and so forth—are most of the remaining 10% and only a couple of percent of the total weight is payload. So when the rocket first takes off, the fuel is mostly lifting itself. So the efficiency of converting the fuel into thrust is critical; small changes in efficiency translate into large changes in payload that can be delivered to great distances.

作为前两个阶段，它们将落回地球。雷达也将能够跟踪其轨迹，并通过落入大气中的方式来测量它们如何减速。如果我们知道舞台的阻力系数，那么原则上，我们可以找出空阶段的重量。问题在于，随着阶段的下降，阶段将以某种复杂的方式翻滚。即便如此，通过测量每个瞬间的雷达横截面，尤其是在各种雷达频率下，并比较一个以上雷达的测量值，一台计算机可以发展出舞台如何掉落然后计算空气电阻的图片，然后从那是空阶段的重量。我不知道准确性是否足够出色，可以根据中国CSS-2导弹的知识来添加我们从其他来源获得的信息。当阶段在大气中分解时，所有赌注都关闭了，但第一个阶段至少可能会击中水。这提出了一个有趣的可能性，可以回收碎片，但预测的影响区域在非常深水上。

根据过去的朝鲜实践，我们知道火箭使用的推进剂的一般类别，但不是精确的类型。氧化剂将是四氧化氮或硝酸或两者的某些混合物。燃料可能是煤油或更有活力的东西，例如二甲基肼。这两个阶段可以使用不同的推进剂。我想知道，通过观察火箭的羽流，也许是从空间中观察到的，以及对光谱的分析，可以确定推进剂的类型。我与几个人讨论了这个想法，共识是您可以识别原子物种，但不能识别比率。因此，这些频谱会揭示氮，但没有足够的信息来知道它来自硝酸或肼。实际上，特定的冲动将是推进剂类型的更好指示。

Remember that radar tracking gives us ratios, of weight to thrust, for example. If we had one, we could calculate the other but we cannot calculate payload mass directly. If this were a ballistic missile test, then the weight of the reentry vehicle could be determined by watching how it decelerated in the atmosphere. Then we could make a guess as to whether they could build a nuclear bomb within that size and weight. But this looks to be a satellite launch. Instead of a reentry vehicle, the rocket will have a small third stage that will push a small satellite into orbit. The payload ends up in a ballistic orbit in space where there is no air resistance (or very little). So a one kilogram satellite will follow the same trajectory as a thousand kilogram satellite. That is unfortunate, because if we knew how much the third stage weighed, or how much the rocket could launch into space, then we could calculate how far the rocket could throw a payload of any chosen weight. Because the payload ends up in space, we have to make some guesses about the weight.

Telemetry offers the potential for a great deal of information. By intercepting telemetry, we could get direct information on fuel flows and the like. Since the Taepodong-2 is still being developed—they have never had a successful launch—one would expect the North Koreans to have the rocket heavily instrumented and to transmit all those data back. They might do that but, in past flights, their telemetry has been quite limited.

Could the United States shoot the rocket down? Well, sort of. We do not have the capability to intercept the boosting rocket. But a satellite has to be boosted up to the point where it enters its orbit. (In fact, that is sort of the definition of the “orbit,” the point where the boosting stops and the object goes into an unpowered ballistic trajectory; if it is a ballistic trajectory that doesn’t later intercept the atmosphere, we call it an orbit.) The United States has already demonstrated that it can intercept low altitude satellites; lat year the Navy拦截一个古老的美国间谍卫星在腐烂的轨道。那t was in some ways an easier target because the path could be calculated days in advance. While the North Korean satellite is still under power and being boosted up to orbit, it will not have a perfectly predictable path, making intercept complex but not impossible especially because, based on the predicted first and second stage impact areas, we can make a good guess about the flight path and the Aegis missile could be positioned to make an intercept of the third stage or the satellite before it reached final orbit. Note that this intercept would destroy the satellite, which is a stunt which is just a North Korean stunt anyway, but does not deny any information to the North Koreans about what they presumably really care about, a two-stage ballistic missile with military applications. So, intercept of the third stage might give the U.S. some macho pleasure but would not accomplish any military goal. (It would have political implications that I won’t even try to guess at.)

这是否意味着宙斯盾会作为洲际弹道导弹防御？不，由于几个原因，例如，弹道导弹不必为轨道上的重新进入车辆供电，火箭燃烧了三到五分钟，RV正在途中，轨迹在途中指向，而不是水平，快速，迅速超出了宙斯盾的范围。

Overall, the outside world will gather a lot of information about the Taepodong-2 as a ballistic missile based on this satellite test. We will not know the exact payload and range of the ballistic missile version but will certainly know a great deal more than we do now. Unfortunately, so will the North Koreans. Especially since their test of a nuclear explosive, this is a dangerous development.