Exempel på nebula

• We have shown that for reasonable assumptions regarding the proto-planetary nebula, magnetic reconnection in a dusty plasma can result in localized heating of dust particles.

• The reason for this revisitation lies in the fact that complex organic matter resembling a petroleum fraction may exist in certain protoplanetary nebulae.

• These objects probably retained the prebiotic material present in the pre-solar nebula and deposited it on our planet.

• More realistically, the nebula would be evolving under the influence of internal viscous forces and the tidal forces of embedded giant planets.

• Among several sources, gas-grain reactions operating in the solar nebula have been well recognized to play an important role in nebular chemistry.

• In any event, the physical aspects of the moon, the planets, the nebulae will be able to be studied and charted under favourable conditions.

• The resulting spectrum is able to match the emission spectrum of a protoplanetary nebula.

• These include the 21 and 30 mm emission features, and the extended red emission observed in protoplanetary nebulae and planetary nebulae.

• The constraints for its formation in the solar nebula are too demanding so it cannot be formed at all under those conditions.

• It has been supposed that the formation of macromolecular material was probably related to thermal alteration in the solar nebula or the meteorite parent body.

• Star-forming regions within the nebulae encountered may thus be seeded by significant numbers of microorganisms.

• Much of the interstellar gas as well as gaseous nebulae are plasmas.

• An average-size star will then shed its outer layers as a planetary nebula.

• Thus, these petroleum fractions can be used as model for the matter present in the interstellar medium or in the protoplanetary nebulae.

• In this introduction, we have started from the observation that petroleum fractions may exist in certain protoplanetary nebulae.