The Mote in God's Eye by Larry Niven, Jerry Pournelle

Cargill.”
    The First Lieutenant sounded resentful when he came on. Blaine was intruding on his dinner party. Rod felt an inner satisfaction for doing it. “Jack, get to the bridge. I want this bird moving. I’ll have a minimum time course to land us on Brigit, and I mean minimum. You can run the tanks, but get us there fast.”
    “Aye aye, sir. Passengers aren’t going to like it.”
    “Rape the— Uh, my compliments to the passengers, and this is a Fleet emergency. Too bad about your dinner party, Jack, but get your passengers into hydraulic beds and move this ship. I’ll be on the bridge in a minute.”
    “Yes, sir.” The intercom went Silent for a moment, then Staley’s voice hooted through the ship. “NOW HEAR THIS. NOW HEAR THIS. STAND BY FOR PROLONGED ACCELERATION ABOVE TWO GRAVITIES. DEPARTMENT HEADS SIGNAL WHEN SECURED FOR INCREASED ACCELERATION.”
    “OK,” Blaine said. He turned to Whitbread. “Punch that damned vector designation into the computer and let’s see where the hell that intruder comes from.” He realized he was swearing and made an effort to calm down. Intruders—aliens? Good God, what a break! To be in command of the first ship to make contact with aliens.
    “Let’s just see where they’re from, shall we?”
    Whitbread moved to the input console next to Blaine’s desk. The screen swam violently, then flashed numbers.
    “Blast your eyes, Whitbread, I’m not a mathematician! Put it on a graph!”
    “Sorry, sir.” Whitbread fiddled with the input controls again. The screen became a black volume filled with blobs and lines of colored light. Big blobs were stars colored for type, velocity vectors were narrow green lines, acceleration vectors were lavender, projected paths were dimly lit red curves. The long green line— Blaine looked at the screen in disbelief, then laid his finger along the knot in his nose. “From the Mote. Well, I will be go to hell. From the Mote, in normal space.” There was no known tramline to the intruder’s Star. It hung in isolation, a yellow fleck near the super giant Murcheson’s Eye. Visions of octopoids danced in his head.
    Suppose they were hostile? he thought suddenly. If Old Mac had to fight an alien ship, she’d need more work. Work they’d put off because it ought to be done in orbit, or dirtside, and now they’d have to do it at two plus gee.
    But it was MacArthur ’s baby—and his. Somehow they’d do it.

5  The Face of God
    Blaine made his way quickly to the bridge and strapped himself into the command chair. As soon as he was settled he reached for the intercom unit. A startled Midshipman Whitbread looked out of the screen from the Captain’s cabin.
    Blaine gambled. “Read it to me, Mister.”
    “Uh—sir?”
    “You have the regs open to the standing orders on alien contact, don’t you? Read them to me, please.” Blaine remembered looking them up, long ago, for fun and curiosity. Most cadets did.
    “Yes, sir.” Visibly, Whitbread wondered if the Captain had been reading his mind, then decided that it was the Captain’s prerogative. This incident would start legends. “‘Section 4500: First contact with nonhuman sentient beings. Note: Sentient beings are defined as creatures which employ tools and communication in purposeful behavior. Subnote: Officers are cautioned to use judgment in applying this definition. The hive rat of Makassar, as an example, employs tools and communication to maintain its nest, but is not Sentient.
    “‘Section One: Upon encounter with sentient nonhuman beings, officers will communicate the existence of such aliens to nearest Fleet command. All other objectives will be considered secondary to this accomplishment.
    Section Two: After the objective described in section one is assured, officers will attempt to establish communication with the aliens, provided however that in so doing they are not authorized to risk their command unless so ordered by higher authority. Although officers will not