Dozens of mysterious objects have suddenly appeared at a shadowy high-security Nevada test range airport.

Satellite imagery from December 6 reveals unusual activity captured outside a dozen hangars of the top secret Tonopah Test Range Airport located on the northern edge of the Nevada Test and Training Range.

The base is known as the facility where aircraft experimented on at the infamous Area 51 base become operational according to The Drive.

The objects were snapped by a Planet Labs' PlanetScope satellite at 10.15am local time, revealing a small fleet of unidentified aircraft in the southern 'canyon' of hangars.

Dozens of mystery objects appeared at the Tonopah Test Range Airport located on the northern edge of the Nevada Test and Training Range on December 6 (pictured)

Just visible: The grainy footage from the satellite picture shows shadows at the exit of the hangars circled

The day before: Satellite images reveal NO unusual activity around the hangars on December 5

The Tonopah Test Range was first created in a program where American fighter pilots secretly flew and tested captured Russian MIGs against their fellow aviators.

Since then the remote airport and range, which boasts over fifty hangars, has become home to the remaining fleet of retired F-117 Nighthawk stealth aircraft.

Today Tonopah and the range support a number of clandestine programs as well as testing, however recently unusual activity has been spotted around a dozen hangars, which has been caught on satellite footage.

But the December 6 satellite image is unique because it revealed some program was active in the hangars that day and roughly fighter-sized jets were pictured outdoors.

The objects were snapped by a Planet Labs' PlanetScope satellite at 10.15am local time, revealing a small fleet of unidentified aircraft in the southern 'canyon' of hangars (illustrated top left in red - here)

The base pictured above in this satellite image from 1990

However, it's not clear what type of aircraft those small white blobs in the satellite images actually are.

They could be unmanned combat air vehicles, RQ-179 Sentinel derivative aircraft, stealth helicopters or manned spy aircraft.

As for now it's still a mystery as to what these objects are and what they will be used for.

One reason they could be out is to troubleshoot any satellite data-link issues before departing. Another theory is that the aircraft may have been out to be fueled.

Experimental: One theory is that the craft pictured could be a fully operational version of the X-45A Unmanned Combat Air Vehicle. A prototype of which is pictured here in 2002

High tech: Another theory from aviation enthusiasts is that the aircraft poking out of the hangars could be a version of the X-47B - which is designed to fly off an aircraft carrier

SPECIFICATIONS OF THE U.S. NAVY'S LATEST STEALTH DRONE Design: Tailless, cranked-kite

Wingspan: 62ft

Length: 32ft

Max Altitude: >40,000ft

Speed: High subsonic

Max Unrefuelled Range: >2,100 nautical miles

Max Unrefuelled Flight Time: >6 hours

Take-off Weight: 44,000lbs

Powerplant: Pratt & Whitney F100-PW-220U

Twin Weapons Bays: 4,500lbs payload Advertisement

Another theory as to whey so many secretive aircraft were captured at the same time is that some speculate the planes are going out on a mission together.

It is not thought that the photographed craft are F-117 jets because their profiles do not match and it known that there are only six left at the base - not nearly a dozen

Furthermore the F-117s are not based in a series of hangars further north on the facility that the satellite images photographed.

A Lockheed F-117 Nighthawk F-117 flying over mountains in Nevada in 2002. The F-117 was officially retired on April 22, 2008 and has since been housed at the Tonopah base

The base has been pretty busy in the second half of 2019. Much of the visible daytime activity picked up by satellite occurs on the northern end of the ramp by the Blue and White clusters.

The base is also an established testing station for USSOCOM aviation-related initiatives.

According to The Drive, Tonopah is a place where secret aircraft end up after being used in experimentation and development states at Area 51.

Once at Tonopah the aircraft become semi-operational or even fully operational - but often remain a secret as with the F-117 and RQ-179 aircraft.