Scientists find first evidence of dynamo generation on an asteroid
About 4.6 billion years ago, the solar system was little more than a tenuous disk of gas and dust. In the span of merely 10 million years, this soup evolved to form today’s massive, complex planets. In the intervening period, however, the solar system contained a mixture of intermediary bodies — small chunks of rock, the remnants of which today are known as asteroids. Although not much is known about the early composition of asteroids, some scientists suspect that such information may reveal an unexpected diversity of planetary bodies within the early solar system. Now a new study published this week in Science has found evidence that Vesta, the second-most-massive asteroid in the solar system, once harbored a dynamo — a molten, swirling mass of conducting fluid generating a magnetic field — resembling that in much larger planets like Earth. Researchers at MIT say the findings suggest that asteroids like...