Why is it better if Interstellar aliens do not really care about human civilization ?

The US Air Force has recently released UFO videos which has caused a surge of speculation about aliens. There is also the possibility that the sightings were of something other than alien spaceships.

18 year veteran F18 pilot with video evidence believes it was aliens

U.S Navy pilot, Cmdr. David Fravor was the commanding officer of the A-41 Black Aces, a squadron of F/A-18 Hornet fighter planes doing an exercise some 60 to 100 miles off the coast between San Diego and Ensenada, Mexico, in advance of a deployment to the Persian Gulf for the Iraq War, he said.

An order came in for him to suspend the exercise and do some “real-world tasking,” about 60 miles west of their location, Fravor said. He said he was told by the command that there were some unidentified flying objects descending from 80,000 feet to 20,000 feet and disappearing; he said officials told him that they had been tracking a couple dozen of these objects for a few weeks.

When they arrived closer to the point, they saw the object, flying around a patch of whitewater in the ocean beneath.

“A White Tic-Tac, about the same size as a Hornet, 40-feet long with no wings,” Fravor described. “Just hanging close to the water.”

The object created no rotor wash – the visible air turbulence left by the blades of a helicopter – he said, and began to mirror the pilots as they pursued it, before it vanished.

“As I get closer, as my nose is starting to pull back up, it accelerates and it’s gone,” he said. “Faster than I’d ever seen anything in my life. We turn around, say let’s go see what’s in the water and there’s nothing. Just blue water.”

If it was aliens then they traveled at least 100 million times farther than the moon

The distance to the moon is 238000 miles.
The distance to the Sun is 93 million miles which is 380 times further than the moon.
A light year is 63400 times farther than the distance from the Earth to the Sun.
The nearest star is about4.2 light years. This is thus over 100 million times further than the moon.

NASA has made over 1000 unmanned missions. There have been about ten times more unmanned versus manned missions.

Voyager 1 is 141 AU from Earth and Voyager 2 is 117 AU from Earth.

New Horizon recently visited Pluto and is now 41 AU from Earth.

Our unmanned space missions have gone over 53000 times further than our manned missions.

The fastest outward-bound spacecraft yet sent, Voyager 1, has covered 1/600 of a light-year in 30 years and is currently moving at 1/18,000 the speed of light. At this rate, a journey to Proxima Centauri would take 80,000 years.

If deceleration on arrival is desired and cannot be achieved by any means other than the engines of the ship, then the lower bound for the required energy is doubled to mass times velocity squared.

The velocity for a manned round trip of a few decades to even the nearest star is several thousand times greater than those of present space vehicles. This means that due to the square of velocity term in the kinetic energy formula, millions of times as much energy is required. Accelerating one ton to one-tenth of the speed of light requires at least 450 petajoules or 4.50×10^17 joules or 125 terawatt-hours (world energy consumption 2008 was 143,851 terawatt-hours) without factoring in the efficiency of the propulsion mechanism.

If the F18 pilot in 2004 saw aliens, then the Tic Tac F18 sized ship probably weighed about 20 tons. The aliens had to decelerate in order to be flying around the Earth.

The minimum energy used to travel normal space would be about 2500 terawatt hours. This assumes the aliens originated from the nearest star. They might need to travel 10 times, 100 times or thousands of times further.

A sample return mission would cost at least another 2500 terawatt hours to fly back to their home system. This would not seem to be worthwhile as any analysis would be doable by a 20-ton vehicle. Also, recall that the Air Force said they were tracking a couple dozen objects for a few weeks. If there were 25 that were the same size then it was 500 tons worth of alien vehicles. Sending one ton of spaceship uses up 0.85 times the energy of our entire civilization for one year. 500 tons of spaceship is at least the power for 425 years of a civilization like ours.

We have already discovered that our solar system has abundant water and all other materials. Earth has nothing that is not abundant elsewhere in the solar system. For life on Earth, it would be far more energy efficient to alter a biosphere to support life than to go to another solar system and take over a biosphere.

Ferdinand Magellan traveled 42,000 miles in his travels around the world with his sailing fleet. Interstellar aliens would be at least like Magellan to an island civilization that never left a 200-yard lagoon. This is the comparative distance of the manned moon missions. However, they did float bottles out two miles.

If humans develop interstellar capabilities then it will first be with vastly better telescopes which could image the surface of exoplanets down to about 1-mile pixel resolution or less. Gigapixel and terapixel imaging of exoplanets out to 100 light years should be doable and affordable. This can happen over the next twenty years.

The next and possibly parallel steps would be to send one gram or so chipsail ships out via laser propulsion for flybys of the nearest stars. This can happen over the next thirty to forty years. It is not just the time to develop the infrastructure and technology it is also the flight times. Once the initial launch systems are created then it would make sense to repeatedly launch the probes. Missions could be sent once per day. A swarm of probes would be sent.

Scaling up the launch systems to send larger vehicles would cost more energy.

We would be very interested in the first alien life forms that are encountered on interstellar missions. We might justify sending many unmanned missions and setting up deceleration on the receiving end. This would be regardless of the technology level of the aliens we encounter.

It is probable that there would be more lower technology or even no technology civilizations than high technology civilizations. If this is the case if humans explored out a few hundred light years and investigated thousands to millions of systems then there would be less interest in the low technology civilizations.

On Earth only a small fraction of the jobs are related to investigating animals and plants.

On Earth, the first lower technology civilizations did not get good treatment. Eventually some lower technology civilizations were not harmed but only studied.

In general it would probably be far safer for us if the Aliens were experienced with interstellar encounters and were even bored with lower technology civilizations.