Biological Sciences in Space
Online ISSN : 1349-967X
Print ISSN : 0914-9201
ISSN-L : 0914-9201
11 巻, 1 号
選択された号の論文の4件中1~4を表示しています
  • 石川 洋二
    1997 年 11 巻 1 号 p. 3-12
    発行日: 1997年
    公開日: 2006/02/01
    ジャーナル フリー
    Five conditions for life to arise are discussed with referring to early Martian environment. The key to determine whether any life form appeared on Mars is found to be the early Martian carbon dioxide atmospheric pressure and then the temperature. The importance to determine the heat flow is indicated. The items to be measured for future Martian exploration are listed. The surface materials, which has been poorly understood, are emphasized for further exploration. Two strategies for search for life on Mars, “step by step” strategy and quick strategy, are suggested.
  • 小林 憲正
    1997 年 11 巻 1 号 p. 13-21
    発行日: 1997年
    公開日: 2006/02/01
    ジャーナル フリー
    McKay et al. Detected polycyclic aromatic hydrocarbons (PAHs) in Martian meteorite ALH 84001 by twostep laser mass spectrometry. From the presence of PAHs, together with other results, they concluded that there were past life of Mars. On the other hands, no organisms nor organic compounds were detected in Martian regolith in Viking experiments in 1976. In order to obtain solid evidence for organisms or bioorganic compounds compounds on Mars, further analyses of Martian samples are required. There may be four classes of organic compounds on Mars, which are (i) organic compounds abiotically formed from primitive Mars atmosphere, (ii) Organic compounds delivered out of Mars, (iii) Organic compounds biotically formed by Mars organisms, and (iv) Organic compounds abiotically formed from the present Mars atmosphere. Possible organic compounds on Mars and analytical methods for them are discussed.
  • 山下 雅道
    1997 年 11 巻 1 号 p. 22-28
    発行日: 1997年
    公開日: 2006/02/01
    ジャーナル フリー
    Scientific debate related to possible martian life is summarized in this article. Even there is no firm conclusion yet to convince the existance of life on Mars, intensive studies on the meteorite ALH84001 have invoked many valuable findings.
  • Takeo Ohnishi, Akihisa Takahashi, Kumio Okaichi, Ken Ohnishi, Hideki M ...
    1997 年 11 巻 1 号 p. 29-34
    発行日: 1997年
    公開日: 2006/02/01
    ジャーナル フリー
    Two strains of cellular slime mold Dictyostelium discoideum, a radiationsensitive mutant and the parental wild-type strain, were used to investigate the effects of microgravity and/or cosmic radiation on their morphology through the whole life span from spores to fruiting bodies for about 7 days in space shuttle of NASA. We found almost no effect of space environment on amoeba cell growth in both strains. It was also observed that almost the same number and shape of fruiting bodies in space compared to the control experiments on earth. These results suggest that there is little effect of microgravity and space radiation on germination, cell aggregation, cell differentiation and cell morphology in the cellular slime mold.
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