Meteor Activity Outlook for January 31-February 6, 2009

February is the only month of the year that sees a fall in rates in both hemispheres. As seen from the northern hemisphere, sporadic rates continue the fall that began in January. This will continue until June when rates reach their nadir. After a brief peak of activity in January, sporadic rates in the southern hemisphere also slide downward until March. Shower activity is low this month but decidedly more interesting in the southern hemisphere. During February there are several sources of activity in the southern morning sky. Most notable is the Alpha Centaurids, which are active during the entire month of February. Other sources are scattered from Carina through Puppis, Vela, and on into Centaurus and Lupus. None of these even rate as a minor shower but together, along with the Alpha Centaurids, create some interesting viewing during the summer nights south of the equator. Only a trace of this activity can be seen from the northern tropics. The Antihelion radiant remains north of the celestial equator and produces a modest 1-2 meteors per hour from Leo. The weak Delta Leonids become active at mid-month but are few and far between, even at maximum activity. During this period the moon reaches it first quarter phase on Monday February 2nd. At this time the moon lies ninety degrees east of the sun and will set near midnight local standard time (LST). Late next week the waxing gibbous moon begins to interfere with morning observations as it sets later and later each morning. The estimated total hourly rates for evening observers this week is near three as seen from the northern hemisphere and four for those situated south of the equator. For morning observers the estimated total hourly rates should be near fourteen for those located in the mid-northern hemisphere (45 N) and twenty for those viewing from the mid-southern hemisphere (45 S). Locations between these two extremes would see activity between the listed figures. These rates assume that you are watching from rural areas away from all sources of light pollution. The actual rates will also depend on factors such as personal light and motion perception, local weather conditions, alertness and experience in watching meteor activity. The radiant positions and rates listed below are exact for Saturday night/Sunday morning January 31/February 1. These positions do not change greatly day to day so the listed coordinates may be used during this entire period. Most star atlases (available at science stores and planetariums) will provide maps with grid lines of the celestial coordinates so that you may find out exactly where these positions are located in the sky. A planisphere or computer planetarium program is also useful in showing the sky at any time of night on any date of the year. Activity from each radiant is best seen when it is positioned highest in the sky, either due north or south along the meridian, depending on your latitude. It must be remembered that meteor activity is rarely seen at the radiant position. Rather they shoot outwards from the radiant so it is best to center your field of view so that the radiant lies at the edge and not the center. Viewing there will allow you to easily trace the path of each meteor back to the radiant (if it is a shower member) or in another direction if it is a sporadic. Meteor activity is not seen from radiants that are located below the horizon. The positions below are listed in a west to east manner in order of right ascension (celestial longitude). The positions listed first are located further west therefore are accessible earlier in the night while those listed further down the list rise later in the night. The following showers are expected to be active this week: The wide Antihelion (ANT) radiant is now centered at 09:40 (145) +13. This area of the sky lies in western Leo, five degrees northwest of the first magnitude Regulus (Alpha Leonis). This radiant is best placed near 0100 LST, when it lies on the meridian and is located highest in the sky. Due to the large size of this radiant, any meteor radiating from eastern Cancer or western Leo could be a candidate for this shower. Rates at this time should be near two per hour no matter your location. With an entry velocity of 30 km/sec., the average Antihelion meteor would be of medium-slow speed. The Alpha Centaurids (ACE) are active from a radiant located at 13:32 (203) -58. This area of the sky is located in southeastern Centaurus, four degrees southwest of the second magnitude star Epsilon Centauri. As seen from the southern hemisphere, current rates would be 2-3 per hour. These meteors are best seen near 0500 local standard time when the radiant lies highest above the horizon. This shower is not visible north of 32 degrees north latitude and also poorly seen in the northern tropics. The southern hemisphere offers a much better view of this activity as the radiant lies much higher in the southern sky. Those located at high southern latitudes will actually encounter morning twilight before the radiant reaches culmination. At 56 km/sec. the Alpha Centaurids will usually produce meteors of swift velocity. As seen from the mid-northern hemisphere (45N) one would expect to see approximately twelve Sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near two per hour. As seen from the mid-southern hemisphere (45S), morning rates would be near fifteen per hour as seen from rural observing sites and three per hour during the evening hours. Locations between these two extremes would see activity between the listed figures. The table below presents a summary of the expected activity this week. Rates and positions are exact for Saturday night/Sunday morning but may be used all week.

[size=-1]SHOWER	[size=-1]DATE OF MAXIMUM ACTIVITY	[size=-1]CELESTIAL POSITION	[size=-1]ENTRY VELOCITY	[size=-1]CULMINATION	[size=-1]HOURLY RATE	[size=-1]CLASS*[/td]
[size=-1]	[size=-1]	[size=-1]RA (RA in Deg.) DEC	[size=-1]Km/Sec	[size=-1]Local Standard Time	[size=-1]North-South	[size=-1]
Antihelion (ANT)	-	09:40 (145) +13	30	01:00	2 - 2	II
Alpha Centaurids (ACE)	Feb 07	13:32 (203) -58	56	05:00	<1 - 3	II

哪个帮翻译一下!我的英文太烂了!

用Google翻译，大概内容就能看懂了。

下文是我用Google翻译导出的，仅供参考：

2月是唯一的一个月的一年将下降，利率在两个半球。作为从北半球，零星率继续下降的1月开始。这将持续到6月利率达到其最低点。经过简短的活动高峰期在1月份，零星的利率在南半球也下滑到3月。淋浴活动低，但在本月果断更有趣的是南半球。 2月期间有几个来源的活动今天上午在南部的天空。最值得注意的是阿尔法Centaurids ，这是活跃在整个2月份。其他来源分散由卡里纳马通过船尾座，船帆座，并在进入半人马座和狼疮性。所有这些甚至率为未成年人的淋浴，但同时，随着阿尔法Centaurids ，创造一些有趣的观赏夜在夏季赤道以南。只有微量的这种活动可以看出北部热带地区。该Antihelion辐射仍然北部的天体赤道和生产适度1-2流星每小时从低地球轨道。狮子座流星雨的薄弱三角洲成为活跃在月中，但是，却并不多见，即使在最大的活动。在此期间，月球第一季度达到这阶段星期一2月2日。此时月亮是90度，东部的太阳，将设置近午夜当地标准时间（反演） 。下周晚些时候的打蜡拱起月亮开始干扰上午意见，因为它集之后，后来每天早上。估算的总费率每小时晚上观察员本周三附近看到从北半球和4个是位于赤道以南。上午观察员估计总数小时费率应该接近14对那些设在中期北半球（ 45 N ）和二十那些从中期南半球（ 45县） 。地点这两极之间会看到列出的活动之间的数字。这些利率假设您正在关注来自农村地区远离所有来源的光污染。实际利率也将取决于个人的因素，如光线和运动知觉，当地的天气状况，警觉和经验，看流星雨的活动。辐射阵地和利率下面列出确切的星期六晚上/周日早上一月31/February 1 。这些立场不会改变大大每天上市的坐标，因此可用于在这整个时期。大多数明星地图集（可在科学商店和天文馆）将提供地图与网格线的天体坐标，以便您可以找到确切位置这些职位都设在了天空。阿planisphere或计算机天文馆计划也是有益的，显示在任何时候天空夜间在任何日期的一年。活动从每个看到辐射是最好的位置时，在天空中最高的，无论是由于北方或南方沿经络，这取决于您的纬度。必须记住，流星雨的活动是很少见到的辐射立场。相反，他们打出的向外辐射，使最好的方法是中心您的视野，这样的辐射处于边缘而不是中心。看那里，您就可以轻松地追踪路径每个流星回到辐射（如果是淋浴会员） ，或在另一个方向如果是零星的。流星雨的活动是不是从radiants位于地平线下。以下的职位列出在西向东的方式，以便权利阿森松（天体经度） 。列在第一位的位置位于西进一步早些时候因此可在夜间，而上市的进一步下降后上升的名单中过夜。以下阵雨预计将在本周活跃：广泛Antihelion （新界适用）辐射中心，现在是09:40 （ 145 ） 13 。这一领域的天空在于西方利奥五度西北第一级雷（阿尔法莱奥尼斯） 。这种辐射是最适合近0100善堂，当位于经络，位于天空中最高的。由于规模大的辐射，任何流星雨辐射东部癌症或西方利奥可能成为候选人这一淋浴。利率在这个时候应该是近两年每小时无论您的位置。同一个项目的速度30公里/秒。平均Antihelion流星雨将中等速度缓慢。阿尔法Centaurids （ ACE ）的活跃从一个辐射设在13点32分（ 203 ） -58 。这一领域的天空位于东南半人马座，四度西南第二级明星小量人马座。作为从南半球，目前的利率将是2月3日每小时。这些流星雨的最佳附近看到当地标准时间0500时，辐射是最高在地平线以上。这是不可见的淋浴以北的北纬32度也很差看到在北部热带地区。南半球提供了一个更好的观点这项活动作为辐射在于更高在南部的天空。这些位于高纬度地区南部将实际遇到的曙光之前，辐射达到高潮。在56公里/秒。阿尔法Centaurids通常会产生流星雨的速度迅速。作为从中期北半球（ 45N ）一个希望看到大约12零星流星每小时在拂晓前最后一小时的从农村观测地点。晚报率将是近两年每小时。作为从中期南半球（ 45秒） ，今天上午率将接近15每小时可以看到来自农村的观测场地和三个每小时在晚上。地点这两极之间会看到列出的活动之间的数字。下面的表格总结了预期的活动，这个星期。利率和立场是正确的星期六晚上/周日早晨，但可用于所有的一周。