| タイトル | Detection of water vapor in Halley's comet |
| 著者(英) | Davis, D. S.; Mumma, M. J.; Weaver, H. A.; Williams, M.; Larson, H. P. |
| 著者所属(英) | Johns Hopkins Univ.|Arizona Univ.|NASA Goddard Space Flight Center |
| 発行日 | 1986-06-20 |
| 言語 | eng |
| 内容記述 | Gaseous, neutral H2O was detected in the coma of comet Halley on 22.1 and 24.1 December 1985 Universal Time. Nine spectral lines of the nus band (2.65 micrometers) were found by means of a Fourier transform spectrometer on the NASA-Kuiper Airborne Observatory. The water production rate was about 6 x 10 to the 28th molecules per second on 22.1 December and 1.7 x 10 to the 29th molecules per second on 24.1 December UT. The numbers of spectral lines and their intensities are in accord with nonthermal-equilibrium cometary models. Rotational populations are derived from the observed spectral line intensities and excitation conditions are discussed. The ortho-para ratio was found to be 2.66 + or - 0.13, corresponding to a nuclear-spin temperature of 32 K (+5 K, -2 K), possibly indicating that the observed water vapor originated from a low-temperature ice. |
| NASA分類 | ASTROPHYSICS |
| レポートNO | 86A43853 |
| 権利 | Copyright |
| URI | https://repository.exst.jaxa.jp/dspace/handle/a-is/383655 |
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