Fenrir, page 45
“The triangulation agrees, and I do not immediately find any other close matches.”
Stephanie glared at the dim dot. It was, in its way, the opposite of Fenrir; that had been too ludicrously bright for its circumstances.
If this was in the asteroid belt, it should be brighter. It would have been hit by the same intensity of radiation, which would be converted ultimately into heating, which would then reradiate out. It would vary some, based on heat capacity, albedo, and so on . . . but in gamma, the reflective albedo of either stony or metallic asteroids wouldn’t be nearly that different.
She bit her lip, thinking. If the object had absorbed the same amount of energy, then . . . “Alerith,” she said slowly, “give me the video of several asteroids from their particular Flashbulb moments on. See if you can do the same for this one.”
After a few minutes, four pictures appeared and ran through a quick video sequence. Three of them looked basically identical; they flared briefly, then quickly went from very bright to very dim to gone.
The mystery dot, however, merely appeared initially in the dim, dim state she had already seen . . . and remained that way for several seconds before fading back out.
“You see that, Alerith?”
“I do. I am unfamiliar with any celestial phenomenon that would behave in that manner.”
“Neither am I.” Her gut was tightening. “Alerith, can you search for any other objects showing a similarly anomalous brightness curve—reaching basically a dim peak and remaining there longer than other objects at that distance?”
“This will take some time. Have you formed a hypothesis?”
A chill had now crept down from her scalp to her spine. “I’m starting to, and I don’t like it one bit.”
Alerith’s simulated skin pulsed with concern. “Can you clarify?”
“If a blast of radiation hits a rock, it’s going to either go through the rock, or get turned to heat when it stops inside the rock. So for an asteroid, that blast of gammas should just warm it up right away, then get radiated off on a standard curve. Right?”
“The exact curve will vary but . . . yes, the general shape and behavior should be similar.”
“The only way I can think of that an asteroid wouldn’t act that way—would act like what we’re seeing—is if it somehow caught the heat in some kind of heat sink, a reservoir, and then reemitted it over a much longer time period.”
Alerith was silent. “But that would make no sense for an asteroid.”
“But it would for a manufactured object. One covered, maybe, by the same material as your radiator, so all heat is distributed across the whole surface, and then to the interior, where it can be more slowly released.”
She looked up to the dim, now menacing, dot. “Something that’s trying to do the almost impossible: hide in space. And it would have stayed hidden, if we hadn’t been watching most of the Solar System when Tulima Ohn went up; even the designers couldn’t have expected a million-ton antimatter flashbulb.”
“Do you believe your people built this?”
“Mine?” She laughed, but there wasn’t much humor in it. “Not mine, or yours. We were asking how your Vorsadama could be targeted so accurately. The answer is the same way we called in artillery strikes in the old days. Forward observers in every possible target. Track the motion of everything in the solar system. In all the solar systems of interest.
“Then, when you’re ready . . . just pull the trigger.”
FINIS
Eric Flint, Fenrir
