Harker David E, Woodward Charles E, Wooden Diane H
Center for Astrophysics and Space Sciences, University of California, San Diego, 9500 Gilman Drive, Department 0424, La Jolla, CA 92093-0424, USA.
Science. 2005 Oct 14;310(5746):278-80. doi: 10.1126/science.1119143. Epub 2005 Sep 15.
Gemini-N observed the properties of dust ejected from the nucleus of comet 9P/Tempel 1 before and after its encounter with Deep Impact. Marked changes were seen in the 7.8- to 13-micrometer spectral energy distribution and derived grain properties of the inner coma. A strong, broad silicate feature dominated by emission from amorphous pyroxene, amorphous olivine, and magnesium-rich crystalline olivine had developed by 1 hour after impact. The ejected dust mass is congruent with 10(4) to 10(6) kilograms on the basis of our models. Twenty-six hours later the silicate feature had faded, leaving a smooth featureless spectrum, similar to that observed before the impact, suggesting that the impact did not produce a new active region releasing small particles on the nucleus.
双子星-N号观测了9P/坦普尔1号彗星核在与深度撞击号相遇前后喷射出的尘埃的特性。在彗发内部7.8至13微米的光谱能量分布以及由此推导的颗粒特性方面观察到了显著变化。撞击后1小时，一个由非晶辉石、非晶橄榄石和富镁结晶橄榄石的发射主导的强烈、宽阔的硅酸盐特征形成。根据我们的模型，喷射出的尘埃质量相当于10⁴至10⁶千克。26小时后，硅酸盐特征消失，留下了一个平滑无特征的光谱，类似于撞击前观测到的光谱，这表明撞击并未产生一个在彗核上释放小颗粒的新活跃区域。
