Some of the helium-3 found in the terrestrial atmosphere is also a relic of atmospheric and underwater nuclear weapons testing, conducted by the three big nuclear powers before 1963.

Some of these mammals would evolve into large forms that would dominate the land, while others would become capable of living in marine, specialized terrestrial, and airborne environments.

Some salamander species are fully aquatic throughout life, some take to the water intermittently, and some are entirely terrestrial as adults.

Some salamanders that are terrestrial have lungs that are used in respiration, although these are simple and sac-like, unlike the more complex organs found in mammals.

Some terrestrial species lack both lungs and gills and perform gas exchange through their skin, a process known as valerian respiration in which the capillary beds are spread throughout the epidermis, and inside the mouth.

Some particle physics experiments must adjust for terrestrial tides.

Some terrestrial radio relays remained in service for regional connections.

Some orders of heterotardigrades are marine, others are terrestrial, but as for all tardigrades, all are aquatic in the sense that they must be surrounded by at least a film of moisture in order to be active-though they can survive in a dormant state if the habitat dries out.

Some diplurans have the ability to shed their cerci if necessary ( autotomy ); of all terrestrial arthropods, only diplurans have the ability to regenerate these lost appendages over a series of moults.

Some populations of the North American caribou migrate the furthest of any terrestrial mammal, travelling up to a year, and covering.

Some ecosystems, such as many wetlands, do not organize as a strict pyramid, because aquatic plants are not as productive as long-lived terrestrial plants such as trees.

Some of the more familiar and better-known gastropods are terrestrial gastropods ( the land snails and slugs ) and some live in freshwater, but more than two thirds of all named species live in a marine environment.

Some botanists however split Huperzia into two genera, Huperzia in the narrow sense including 10-15 species of terrestrial temperate to Arctic species, and the rest in Phlegmariurus, a primarily tropical to subtropical genus of mainly epiphytic species.

Some terrestrial mammals, especially desert rodents appear to survive without drinking but they do generate water through the metabolism of cereal seeds and they also have mechanisms to conserve water to the maximum degree.

Some terrestrial ecosystems – for example, those of the open deserts and similar arid environments – exist on irregular rainfall and the moisture it delivers to the soil, supplemented by moisture in the air.

Some digital broadcasting systems allow single-frequency network ( SFN ), where all terrestrial transmitters in a region sending the same multiplex of radio programs may use the same frequency channel without self-interference problems, further improving the system spectral efficiency.

Some MATV systems may carry 8-VSB and QAM signals, mostly in apartment buildings and similar facilities that use a combination of terrestrial antennas and cable distribution sources ( such as HITS or " Headend in the Sky ", a unit of Comcast that delivers digital channels by satellite to small cable systems ).

Some exposed outcrops appear to show faint layering, and some researchers also believe that landforms visible in images of the mouth of Ma ' adim Vallis where it enters Gusev resemble landforms seen in some terrestrial river deltas.

Some species are terrestrial and are found under logs, in or on the soil, and on plants in humid areas.

Some structures resembling the mineralized casts of terrestrial bacteria and their appendages ( fibrils ) or by-products ( extracellular polymeric substances ) occur in the rims of carbonate globules and preterrestrial aqueous alteration regions.

Some parts of the world, notably in France and the US, have also offered encrypted analog terrestrial signals, available for subscription.

Some terrestrial species throw a thread of mucus which they use as a rope to climb from one leaf to another.

Some networks use 32 kbit / s ADPCM on the terrestrial side of the network instead of 64 kbit / s PCM and the TRAU converts accordingly.

Some 500 species are found in fresh water ; and another 5, 000 species are the woodlice in the suborder Oniscidea, which are thus by far the most successful group of terrestrial crustaceans.

Some amateur astronomers use home-made radio telescopes, while others use radio telescopes that were originally built for astronomy research but have since been made available for use by amateurs.

Some exoplanets have been directly imaged by telescopes, but the vast majority have been detected through indirect methods such as radial velocity measurements.

Some others, such as the Double Cluster, are barely perceptible without instruments, while many more can be seen using binoculars or telescopes.

Some of the more notable frequency bands used by radio telescopes include:

Some space and ground based telescopes that have studied high energy astronomy include the following:

Some residents enjoy biking around the vast spaces north of the town ; at night, avid stargazers bring their telescopes to marvel at the universe.

Some are classified by the task they perform such as Solar telescopes,

Some telescopes use primary mirrors which are made differently.

Some of the telescopes operated by the US Department of Defense are involved in researching man-made ( e. g. spacecraft, monitoring satellites, rockets, and laser technology ) rather than celestial objects.

Some have sea views, telescopes and balconies.

Some of these dark GRBs fade in the optical very rapidly, others are dimmer but detectable with large ( meter class ) telescopes.

Some telescopes use deliberately astigmatic optics.

Some of the telescopes are occasionally used for EVN and VLBI observations in order to create an interferometer with even larger baselines, providing images with much greater angular resolution.

Some amateur astronomers use their telescopes the same way, but direct optical viewing with eyepieces is still very common.

Some of these objects are bright enough to find and see in binoculars and small telescopes.

Some motorized telescopes sold during the mid 80s to early 90s, including the Celestron Compustar ( r ) which used a form of GoTo technology, were not programmed to allow for dates after 2000 ; making some Celestron products susceptible to the Y2K bug.

Some watch the Spooklight through binoculars or even telescopes.