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Gennady Detinich
The cigar-like asteroid Oumuamua has given astronomers an interesting mystery. It appeared from nowhere at a speed for interstellar travel, and after a maneuver near the Sun, began to move away with an unusually large acceleration that cannot be explained by gravity alone. A similar trick could be pulled by an interstellar cruiser or a comet, but the first is incredible in itself, and the second did not manifest itself in any way, for example, in the form of a comet’s tail. What was it?
Asteroid ‘Oumuamua as imagined by an artist. Image Source: ESO
In the latest issue of the magazine Nature came out article two astronomers, in which, they believe, explained all the oddities of the behavior of the asteroid Oumuamua, without fantastic assumptions and distortions.
Molecular hydrogen is to blame, scientists are sure. Passing near the Sun from a solid frozen state to a gaseous state in the process of sublimation, hydrogen played the role of gas engines that gave the asteroid ‘Oumuamua an unusually high acceleration without visible traces of evaporation. Unlike the sublimation of water ice, as in the case of comets, hydrogen remains invisible to observations in optical telescopes. Therefore, it was impossible to detect the comet-like acceleration of ‘Oumuamua using ordinary observations, while others, for example, in the radio range, did not think of doing it.
In addition, simulations have shown that if the asteroid received non-gravitational acceleration from the evaporation of water ice, this would explain only 50% of the increase in speed, while molecular hydrogen emissions fit perfectly into the obtained data on the asteroid’s trajectory. But where does the deposit of molecular hydrogen come from in an asteroid? It’s simple, scientists say. The process of the impact of ionized radiation on water has long been known, during which water molecules are split, and the same molecular hydrogen is obtained.
The asteroid ‘Oumuamua traveled indefinitely through interstellar space, where ionized radiation bombarded its surface and innards. The molecular hydrogen arising there remained trapped in the water ice until the passage near the Sun melted the ice and allowed the hydrogen to escape through peculiar thawed nozzles into space and give the asteroid acceleration. The melting of the ice was relatively modest and therefore we did not observe a tail at Oumuamua, but the evaporating hydrogen did its best so that some scientists suspected an interstellar ship or a natural object adapted for this mission in the asteroid.
According to the authors of the work, this “can explain many of ‘Oumuamua’s special properties without fine-tuning or resorting to extraordinary claims about the nature of the object.”