I told the girls all I knew of the approaching wanderer. The density was similar to that of Earth. The oncoming velocity and the calculated elements of its orbit now were such that within a few weeks more the new planet would round our Sun and presumably head outward again. It would pass within a few million miles of us, causing a disturbance to Earth's orbit, even a change of the inclination of our axis, affecting our tides and our climate.
"So I've heard," Venza interrupted me. "They say that, and then they stop. Why can't a newscaster tell you what is so mysterious?"
"For a very good reason, Venza: because you can't throw people into a panic. This whole thing, up to today, has been withheld from the public of Earth and Venus. The Martian Union tried to withhold it, but could not. Every heliogram between the worlds is censored."
"And still," said Venza sarcastically, "you don't tell us what is so mysterious about this wanderer."
"For one thing," I said, "it changes its direction. No normal heavenly body does that. They calculated the elements of its orbit last April. They've done it twenty times since, and every time the projected orbit is different. Just a little at first, but last week the accursed thing actually took a sudden turn, as though it were a spaceship."
The girls stared at me. "What does that mean?" Anita asked.
"They're beginning to make wild guesses but we won't go into that."
"What else is mysterious?" Venza demanded.
"The thing isn't normally visible."