I think you mean without producing a sonic boom- that speed is far in excess of the speed of sound.

Hi Bearded Bruce.

That is exactly what I meant. Thank you for catching that error.

A sonic boom is what occurs when a plane flies faster than the speed of sound.

The speed of sound fluctuates depending on the altitude, and the atmospheric conditions at the time. If memory serves; the speed of sound varies deom 734-749MPH at sea level.

I have to agree with BillD- I am certain that alien species with high technology exist, I just doubt that they would travel here and remain hidden.

I have never seen an alien; so I am unsure whether Aliens came here and remain hidden For all we know they may have some rules like the prime directive in Star Trek.

As far as my sightings of UFOs; they may have been classified government projects for all I know.

I will say that Einstein's perception that nothing can travel faster than lightis bunk. Sub atomic particles have been known to exceed the speed of light.

For all we know; the aliens may be able to enter a different dimension where there are different laws of physics.

The ancient Kabbalists claimed there were 10 different dimensions. Even theoretical physicist Michio Kaku Ph.D believes there are between 10 (hmmmmm) and 26 different dimensions. Dr. Kaku is the author of several books "Hyperspace" the most known, and teaches phusics at New York university.