E and F
The third planet from the Sun.
The blocking of some or all of the
light from one object by another. This eclipse image is courtesy
of NASA DFRC.
- Electric charge
- A physical state based on the amount and location of electrons and
protons in matter. Matter with more electrons than protons is negatively charged. Matter that attracts free electrons is positively charged.
- The negatively charged part of an atom. It orbits the atom's nucleus. Electrons are very light compared to protons and
More about electrons...
- Electron volt (eV)
- The unit used to describe the total energy carried by a particle. It is the energy gained by an electron (or proton, same size of electric charge) moving through a voltage difference of one volt.
- Electrostatic analyzer
- An instrument that identifies particles by measuring the electrostatic deflection in the system. This instrument is in both the SWEPAM and SWICS instruments on the ACE spacecraft.
- Electrostatic deflection
- The amount of bending of a particle's flight path in a constant electric
field. This property is used in an electrostatic analyzer.
- A material consisting of atoms, all with the same atomic number. Approximately 90 different elements are known to exist in nature and several others have been created in nuclear reactions. For more information about the elements, see the Periodic Table of the Elements.
- The ability to do work. There are many types of energy including light, electricity, heat, and nuclear energy.
- Energy-loss stack
- The arrangement in an instrument of a stack of detectors, each of which measures the energy loss of particles as they slow and stop in the stack. Energy-loss stacks are used in both the SIS and CRIS instruments on the
- An imaginary line around the center of a body where every point on the line
is an equal distance from the poles. The equator defines the boundary between the northern and southern hemispheres.
- Outside our galaxy.
- The rate of particle flow over time.
- A type of nuclear reaction in which two atomic nuclei combine to form a heavier nucleus, releasing energy.
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