流星目视观测

流星目视观测

    一个简单的流星观测方法就是我们所说的“计数方法”。观测者使用录音机或者纸笔来记录流星的个数，估计流星的星等并判断是否属于要观测的流星群（比如属于英仙座流星群或者不属于）。这个方法可以适用于大流星群，例如象限仪座流星雨，英仙座流星和双子座流星雨。

    你要决定哪种观测方法可以顺利的使你进行观测，绘图还是计数。从你决定去观测，你必须明白这些问题：绘图的主要缺点是当你绘图的这部分时间对于观测是无效时间。如果流星频率很高，你可能要在你观测的时间中花费一半来绘图，这样的观测结果就变得相当不可靠，这种情况发生在所有流星活动较大时，例如在八月或者十月。或者当主要的大流星群在活动的时期。想象一下你将要在十月观测，一个大流星群猎户座流星群和两个小流星群金牛座流星群、双子座epsilon流星群正在活动。这样的流星频率除非你能将每个你看到的流星画下来。在这种情况下，你应当比较两种流星的观测方法了。
    使用绘图方法观测所有可能属于两个小流星群的流星，但是流星明显归属于猎户座流星群和偶发流星的可以使用计数方法。这就是说，当你记录前一颗流星时眼睛不离开天空，用录音机记录最新的一颗流星数据（或者写下你看到的详细情况）。这样的话你就降低了无效时间，仍然确保了这个小流星群观测的精确度。当你一小时观测超过20颗流星时，你只要画出属于这个小流星群的流星，其他的流星可以只计数。
    记录开始和结束观测的时间，这个大流星群可以被认为只有较小活动。
只要你每小时观测到的流星少于20颗，你就可以把每颗你看到的流星画下来。当流星频率很高时，如每小时50颗，你只要专注于产生这个较大活动的流星。

来源 http://www.imo.net/visual

Visual Meteor Observation

An easy way to observe meteors visually is what we call the 'counting method.' The observer notes the meteors seen on a tape recorder or just a piece of paper. He gives the estimated magnitude of the meteor and whether or not it belonged to the observed shower (e.g. Perseid or non-Perseid). This method is applicable for major shower maxima like the Quadrantids, Perseids, and Geminids.

You have to decide which observing method, plotting or counting, can be used most favourably. Since you want to have as much information as possible out of your observation, the answer to this question seems to be clear: plotting. But plotting has the main disadvantage that the time used for plotting meteors is dead time. If the meteor frequency is too high, it may happen that you spend, say up to 50% of your observing time for the plotting procedure. Such an observation becomes quite unreliable. This situation occurs when the total meteor activity is high, such as in August or October, or when a major shower is active.

Imagine you want to observe in October. Then a major shower, the Orionids, and two minor showers, the Taurids and epsilon-Geminids, are active. The meteor frequency may be such that your observation becomes useless if you plot each meteor seen. In this case you should combine both methods.

All meteors which could belong to one of the minor showers are plotted while obvious Orionids and Sporadics are "counted" according to the guidelines for major-shower observations, i.e. you record the latter meteor data onto tape (or write the details as notes) without taking your eyes off the sky, while plotting the former meteors. In this way you reduce the amount of dead time but still enable an accurate shower association to be obtained for the minor showers.

As soon as you see more than 20 meteors per hour you should plot only meteors which could belong to a minor shower; other meteors are "counted" only.

Please note that at the beginning and near the end of their activity periods the major showers have to be considered as minor ones as well since they then produce low rates.

As long as you see less than 20 meteors per hour you can plot all meteors seen, and when the frequency becomes very high, say 50 meteors per hour, you should only concentrate on the major shower which causes this activity.

好家伙！和gohomemen 一样牛！

先加15MFB鼓励！