The Alpha Quadrant
Station Log, Commander Benjamin Sisko, Stardate 46393.8: I am settling into command of Deep Space 9, the former Cardassian mining station, now a Federation outpost located in the Denorios Belt of the Bajoran system.
I have decided to take another visit through the nearby wormhole that provides a shortcut from the Alpha Quadrant of the galaxy DS9 and Bajor is in, into the Gamma Quadrant 70,000 light years away.
Lieutenant Commander Jadzia Dax, the station science officer, will accompany me through the wormhole on an exploratory mission. My expectations are to go through the wormhole, conduct our findings, and return to DS9 and the Alpha Quadrant without incident.
USS Rio Grande
Starfleet Danube-class runabout
"Wonder what we'll find on the other side, Benjamin?" Dax asked. "Now that we'll be able to go through unimpeded."
"The unknown," Sisko replied. "Slowing to one-fourth-quarter impulse. The wormhole should open up--"
The commander was interrupted by a beep from the console at his flight controller station.
"Commander, I'm reading some very unusual neutrino readings," Dax said.
"From the wormhole?"
"Negative. The disturbance isn't coming from the wormhole. It's about 200,000 kilometers off our stern."
"I'm bringing the runabout to a full stop. Sisko to Ops: our sensors are reading a major neutrino disturbance."
On board Deep Space Nine, within the Operations Center, Bajoran Major Kira Nerys oversaw a busy crew of Starfleet and Bajoran officers. "We're reading the same thing," Kira said. "This disturbance is in the Denorios Belt, same distance from the sun as the wormhole, in a different place."
"The location is fixed, Major, but in the opposite direction," said Starfleet Lieutenant Kaine.
"How so?" she asked.
"Major, on the Lagrangian point scale, if Bajor's sun is the center; Bajor at L1; and the wormhole at L3; then the disturbance is at L5."
"Did you get that, Commander?"
"Loud and clear," Sisko replied. "The Gamma Quadrant can wait. Dax, turn the Rio Grande around. We're going to see what's going on here."
"Commander, I recommend keeping your distance," Kira said, her voice coming through the com. "We don't know what we're dealing with."
"Understood, Major. I have every intention of taking care. And, every intention of seeing what this is myself. We'll keep this channel open."
"Affirmative, Commander," Sisko and Dax heard Kira say.
The Rio Grande turned from the wormhole and proceeded to the place where the neutrino disturbance was detected.
"Ten thousand kilometers from the disturbance and closing," Dax reported. "Slowing to one-eighth impulse. This is as good a time as any to begin scans."
"I agree, Lieutenant," Sisko said. "Bring the Rio Grande within 50 kilometers."
"While I understand Major Kira's concern, preliminary scans didn't indicate any danger from this phenomenon."
"No, Commander, they didn't. However, any further scans can be done at this distance, or from the station itself if necessary."
"We could," Sisko replied, "or we can get our hands a little dirty. What do you say...Old Man?"
Dax smiled, and guided the Rio Grande to within fifty kilometers of the disturbance.
"Captain, I'm noticing some similarities between this, and the wormhole--"
"Wormhole? A second wormhole?" Sisko replied. "Did you hear that, Major?"
"Yes, Captain, and I recommend--"
Without any warning, the star-specked blackness of space that the Rio Grande was looking out on exploded in light. Before either Sisko or Dax could react, another wormhole had opened, and the runabout was inside.
The Rio Grande traveled safely through the second wormhole. Instead of emerging somewhere else in the galaxy, though, the Rio Grande found itself halfway between a planet and its moon. The system's sun could be seen in the distance, as the runabout was over the planet's night side.
"Oxygen/nitrogen atmosphere like a Class M planet, 78 percent nitrogen, 21 percent oxygen," Dax replied. "Readings indicate an industrial civilization, spacecraft in orbit. Life forms on the planet's moon."
Sisko, listening to Dax, also was looking closely at the city lights on the surface of the planet.
"...possible Type I civilization," Dax continued. "I'm picking up signals on multiple frequen--"
She stopped talking briefly when she noticed something on the sensors.
"Warp signature?" Dax scanned the source of the signature. "A ship, twice as large as the Rio Grande and equipped with a primitive warp drive."
"Primitive?" Sisko asked.
"Not much more advanced than Zefram Cochrane's test vehicle, but definitely a warp-capable ship...as I said, I'm also picking up signals consistent with 21st-century Earth, military and civilian...Benjamin, I've just noticed a spike in signals from the lunar surface."
"I hope we haven't been spotted," Sisko deadpanned, realizing the opposite was likely the truth.
"Military. I'll put it on the com."
She picked up the transmission in mid-stream. "--unidentified object appeared out of the, ah, cosmic cloud or whatever that thing was. It's stationary for the moment--"
"We've been spotted, Old Man," Sisko said, his eyes locked on the light pattern of the northern continent. "Perform an astrometic scan and tell me exactly what it indicates."
Dax performed the scan. "Captain, according to these scans, we're orbiting--"
"Earth," Sisko replied. "But not the one we know."
"Area scans indicate the largest object in orbit are a Stanford torus above the northern continent," Dax said. "The moon has a series of small bases holding about 5,000 people. However the astrometic scans don't indicate we travelled back in time; they're what you'd expect to see if we were orbiting the Earth we're familiar with right now."
"So the question isn't WHEN we are, but WHERE," Sisko mused.
"Alternate universe!" they both said simultaneously, moments later.
Leaving unnoticed was no longer an option. The wormhole and the Rio Grande had already been seen, and not just by military surveillance from the lunar surface and satellites orbiting the planet. The opening of the wormhole was visible to anyone on the planet's surface.
On both sides of the second wormhole, the destinies of several civilizations had changed forever.