Gold along with Silver and Copper are excellent conductors of both electricity and heat because of the single outer electron that is mostly lost to the atom and is free to move around the metal. These free electrons are easily displaced when a voltage is applied. While Silver has the highest electrical conductivity of any of the metals, Gold has the advantage of greater corrosion resistance.

Explorer 1 was the first U.S. satellite and the first satellite to carry science instruments. The primary science instrument on Explorer 1 was a cosmic
ray detector designed to measure the radiation environment in Earth orbit.
The satellite was launched on Jan. 31, 1958, from Cape Canaveral in Florida.
Explorer 1 followed a looping flight path that orbited Earth once every 114 minutes. The satellite itself was 80 inches long and 6.25 inches in diameter. It entered Earth's atmosphere and burned up on March 31, 1970, after more than 58,000 orbits. (Courtesy: NASA).

The Parker Solar Probe will perform its scientific investigations in a hazardous region of intense heat and solar radiation. Flying into the outermost part of the sun's atmosphere, known as the corona, Parker Solar Probe will employ a combination of measurements and imaging to revolutionize our understanding of the corona and expand our knowledge of the origin and evolution of the solar wind. (Courtesy: NASA).

The Orbiting Carbon Observatory 2, or OCO-2, is an Earth satellite mission designed to study the sources and sinks
of carbon dioxide globally and provide scientists with a better idea of how carbon is contributing to climate change. The mission launched July 2, 2014, from Vandenberg Air Force Base in California. (Courtesy: NASA/JPL).

The Optical Payload for Laser (communications) Science, or OPALS, is a technology demonstration aboard the International Space Station designed to test the use of focused laser energy for space communications. OPALS arrived at the space station on April 20, 2014, aboard SpaceX's Dragon cargo spacecraft. (Courtesy: NASA/JPL).

Soil Moisture Active Passive, or SMAP, is an Earth satellite mission designed to measure and map Earth's soil moisture and freeze/thaw state to better understand terrestrial water, carbon and energy cycles. Using an advanced radiometer, the satellite peers beneath clouds, vegetation and other surface features to monitor water and energy fluxes, helping improve flood predictions and drought monitoring. Launched early 2015. (Courtesy: NASA/JPL).

The Nuclear Spectroscopic Telescope Array, or NuSTAR mission will study the universe in high energy X-rays to better understand the dynamics of black holes, exploding stars and the most extreme active galaxies. Launched in 2012. (Courtesy: NASA/JPL).

The Geostationary Operational Environmental Satellite-R Series (GOES-R) is the nation’s next generation of geostationary weather satellites. The GOES-R series will offer improved detection and observation of environmental phenomena that directly affects public safety, protection of property and our nation’s economic health and prosperity. (Courtesy: NASA).

The LUX (Large Underground Xenon) experiment is a 370 kg liquid xenon time-projection chamber that aims to directly detect galactic dark matter in an underground laboratory 1 mile under the earth, in the Black Hills of South Dakota, USA. Dark Matter comprises 23% of the energy density of the universe. Detecting its interactions with normal matter, and studying its properties, is one the most challenging problems in modern day physics. (Courtesy:Sanford Underground Research Facility/UC Berkeley.)

Juno's Mission:
Determine how much water is in Jupiter's atmosphere, which helps determine which planet formation theory is correct. Look deep into Jupiter's atmosphere to measure composition, temperature, cloud motions and other properties. Map Jupiter's magnetic and gravity fields, revealing the planet's deep structure. Explore and study Jupiter's magnetosphere near the planet's poles, especially the auroras – Jupiter's northern and southern lights –providing new insights about how the planet's enormous magnetic force field affects its atmosphere. (Courtesy NASA/JPL).

Jupiter's Great Red Spot is a large storm system similar to a hurricane on Earth, except much larger - about three times the size of Earth. Located in Jupiter's southern hemisphere, the storm rotates counterclockwise, with one rotation taking about 6 days. It has endured for at least the last 400 years. This is one of the latest images (7/2017) from the Juno Spacecraft. (Courtesy: NASA/JPL).

A closeup view of a solar eruption shooting out into space as seen by NASA's STEREO-B on March 12, 2012. The orange image is of extreme ultraviolet light, while the part of the image in green is from a different STEREO telescope showing visible light beyond the edge of the solar disk. (Courtesy NASA/JPL).

STEREO (Solar TErrestrial RElations Observatory) is the third mission in NASA's Solar Terrestrial Probes program (STP). The mission, launched in October 2006, has provided a unique and revolutionary view of the Sun-Earth System. The two nearly identical observatories - one ahead of Earth in its orbit, the other trailing behind - have traced the flow of energy and matter from the Sun to Earth. STEREO has revealed the 3D structure of coronal mass ejections; violent eruptions of matter from the sun that can disrupt satellites and power grids, and help us understand why they happen. (Courtesy NASA/JPL).

Advanced Composition Explorer (ACE) observes particles of solar, interstellar, interplanetary, and galactic origins, spanning the energy range from solar wind ions to galactic cosmic ray nuclei. ACE also provides near-real-time solar wind information over short time periods. When reporting space weather, ACE can provide an advance warning (about one hour) of geomagnetic storms that can overload power grids, disrupt communications on Earth, and present a hazard to astronauts. ACE orbits the L1 libration point which is a point of Earth-Sun gravitational equilibrium about 1.5 million km from Earth and 148.5 million km from the Sun. Launched August 1997. (Courtesy NASA/CALTECH).

THEMIS is a mission to investigate what causes auroras in the Earth's atmosphere to dramatically change from slowly shimmering waves of light to wildly shifting streaks of color. The process that triggers substorms occurs deep within the Earth's magnetosphere, the region of space surrounding the Earth that is dominated by the Earth's magnetic field. At substorm orbit, stretched magnetic field lines snap back to a configuration similar to that of a bar magnet, energizing charged particles and dumping them into the Earth's upper atmosphere, where they produce shimmering aurora that can be seen at high latitudes in both the northern and southern hemisphere. Discovering what causes auroras to change will provide scientists with important details on how the magnetosphere works and the important Sun-Earth connection. Launched February 2007. (Courtesy NASA/UC BERKELEY).

NASA's Earth Observing System is a series of polar-orbiting satellites designed for long term global observations of the land surface, biosphere, solid Earth, atmosphere and oceans. Some of the satellites in the EOS series are AQUA, AURA, CALIPSO, CLOUDSAT and TERRA. (Courtesy NASA/JPL).

Providing insight into our planet's global hydrologic cycle, Aqua is part of NASA's EOS series of satellites. AQUA will collect data on global precipitation, evaporation, and the cycling of water as it observes our Earth's oceans, atmosphere, land, ice, snow cover and vegetation. Launched May 2002. (Courtesy NASA/JPL).

AURA is another EOS satellite that will be used to gather data on the dynamics of the Earth's upper and lower atmosphere and its underlying chemistry. Aura will study trace gasses in the atmosphere so we can better understand global climate change, global warming, the global movement of polluted air, and ozone depletion in the stratosphere. Launched July 2004. (Courtesy NASA/JPL).

NASA's Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) spacecraft is designed to study the role that clouds and aerosols play in regulating Earth's weather, climate and air quality. Calipso's instruments will provide statistics on the geographic and vertical distribution of aerosols around the globe and also monitor subvisible clouds in the upper troposphere and polar stratospheric clouds. Launched May 2006. (Courtesy NASA/JPL).

NASA's CLOUDSAT satellite, in conjunction with CALIPSO, will be used to study the role that clouds and aerosols play in regulating Earth's weather, climate and air quality. CLOUDSAT's primary instrument is a 94 GHz cloud profiling radar that will be used to provide estimates of the percentage of Earth's clouds that produce rain. The radar will also provide vertically-resolved estimates of how much water and ice are in Earth's clouds and estimate how efficiently the atmosphere produces rain from condensates. Launched May 2006. (Courtesy NASA/JPL).

NASA's TERRA satellite is considered the flagship mission in NASA's Earth Observing System. TERRA carries five instruments that observe Earth's atmosphere, ocean, land, snow, ice, and energy budget. TERRA observations will reveal humanity's impact on the planet and provide crucial data about natural hazards like fire and volcanoes. Launched December 1999.
(Courtesy NASA/JPL).

The Kepler Mission is specifically designed to survey our region of the Milky Way galaxy in order to locate Earth-size and smaller planets in or near the habitable zone of its parent star and also to determine the fraction of the hundreds of billions of stars in our galaxy that might have such planets. Kepler finds planets by looking for tiny dips in the brightness of a star when a planet crosses in front of or transits the star. Launched March 2009. (Courtesy NASA/JPL).

Mars Odyssey is an orbiter carrying science experiments designed to make global observations of Mars to improve our understanding of the planet's climate and geologic history, including the search for water and evidence of life-sustaining environments. One of the chief scientific goals that 2001 Mars Odyssey will focus on is mapping the chemical elements and minerals that make up the Martian surface. Odyssey also served as a communication relay for landers such as the Mars Exploration Rovers Spirit and Opportunity. Launched April 2001. (Courtesy NASA/JPL).

The Mars Atmosphere and Volatile EvolutioN or MAVEN mission will orbit Mars to explore how the sun may have stripped Mars of most of its atmosphere, turning a planet once possibly habitable to microbial life into a cold and barren desert world. MAVEN will be the first spacecraft mission dedicated to exploring the upper atmosphere of Mars. Launched November 2013. (Courtesy NASA/JPL).

New Horizons is a mission designed to fly by Pluto and its moon Charon and transmit images and data back to Earth. It will then continue on into the Kuiper Belt where it will fly by one or more Kuiper Belt Objects and return further data. The primary objectives are to characterize the global geology and morphology and map the surface composition of Pluto and Charon and characterize the atmosphere of Pluto and its escape rate. Launched on 19 January 2006, flyby of Pluto will occur nominally on 14 July 2015. (Courtesy NASA/JHUAPL/SwRI).

The Deep Space Climate Observatory, or DSCOVR, will maintain the nation's real-time solar wind monitoring capabilities which are critical to the accuracy and lead time of NOAA's space weather alerts and forecasts.
Without timely and accurate warnings, space weather events like the geomagnetic storms caused by changes in solar wind have the potential to disrupt nearly every major public infrastructure system, including power grids, telecommunications, aviation and GPS. (Courtesy NASA).

In this photo, captured by the AQUA satellite, the Barents Sea north of Norway is awash in colorful swirls of blue and green in July of 2003. This spectacular display of color reveals the biological richness of these cold, nutrient rich waters with a bloom of tiny marine plants called phytoplankton.
The colors can be produced by a variety of pigments, including chlorophyll, that the plants use to harness sunlight for photosynthesis. The brightest blue color is sometimes the result of a kind of phytoplankton called a coccolithophore that has a calcium carbonate (chalk) covering. This chalky covering is bright white, and mixes with the blue reflection off the water to produce brilliant hues. (Courtesy NASA/JPL).

In July 2012, a massive ice island broke free of the Petermann Glacier in northwestern Greenland. On July 16, the giant iceberg could be seen drifting down the fjord, away from the floating ice tongue from which it calved.

On July 21, 2012, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite captured this image of the iceberg's continuing journey. This image has been rotated and north is toward the right. This detailed image reveals that the iceberg covers an area of about 32.3 square kilometers (12.5 square miles). (Courtesy NASA/JPL).

This Mars surface image was taken by the Thermal Emission Imaging System (THEMIS) on board the Mars Odyssey spacecraft. The image shows an impact crater with ejecta that does not completely encircle the crater. This typically indicates the impact occurred at an angle. (Courtesy NASA/JPL/ASU).

Charon and Pluto: This composite of enhanced color images of Pluto and Charon was taken by NASA’s New Horizons spacecraft as it passed
through the Pluto system. (Courtesy: NASA).