Forth kind 

First kind, Sighting.
Second Kind, facts.
Third Kind, Contact
FORTH KIND, Obduction.

The aircraft came over us, and pulled us into it, It was nothing Anyone has ever seen, Terrifying. Making us crave Suicide.. It was the, Forth Kind

Forth kind by ParanoidKid July 1, 2010

Long-Duration Motion Machines of the Fourth Kind (LDMM4)

The comprehensive approach: devices that simultaneously respect all laws of thermodynamics while eliminating friction to the maximum extent—the ultimate expression of long-duration motion engineering. LDMM4 combine the energy storage optimization of LDMM1, the entropy-slowing strategies of LDMM2, and the friction elimination of LDMM3 into a single system. They're not violating physics; they're just exploiting every possible loophole to make motion last as long as physically possible. A supercooled, magnetically levitated flywheel in perfect vacuum, isolated from cosmic rays, spinning on energy stored once at the beginning—that's LDMM4. It will outlast human civilization, maybe the planet, maybe the star. LDMM4 is what you build when you want something to move longer than anything has ever moved before.

Long-Duration Motion Machines of the Fourth Kind (LDMM4) "They're designing time capsules that will spin for millions of years using superconducting magnetic levitation in deep space. That's LDMM4—all the laws respected, all the losses minimized, all the friction eliminated. It won't move forever, but it'll move longer than you can imagine. LDMM4 is the closest we'll ever get to eternity without cheating."

Long-Duration Motion Machines of the Fourth Kind (LDMM4) by Dumu The Void March 1, 2026