- MACHOs
- Massive Compact Halo Objects
- magnetic storms
- Magnetic storms
- A large-scale disturbance of the magnetosphere, often initiated by the arrival of an interplanetary shock originating at the Sun.
- magnetopause
- Magnetopause
- The boundary surface between the solar wind and the magnetosphere where the pressure of the magnetic field equals the pressure of the solar wind
- magnetosphere
- Magnetosphere
- magnetosphers
- Magnetosphers
- The region surrounding a celestial body where its magnetic field controls the motions of charged particles.
- magnetotail
- Magnetotail
- The portion of a planetary magnetosphere which is pushed in the direction of the solar wind
- Maunder minimum
- A 70-year period from 1645 to 1715 when sunspots were rare.
- MEPAG
- Mars Exploration Planning & Analysis Group
- mesoscale
- Mesoscale
- Of or relating to a meteorological phenomenon approximately 10 to 1000 kilometers in horizontal extent.
- meteor
- Meteors
- meteors
- Meteor
- Any of the small particles of matter in the solar system that are directly observable only by their incandescence from frictional heating on entry into the atmosphere.
- meteorites
- metetorite
- Meteorites
- Meteorite
- A meteor that reaches the surface of the earth without being completely vaporized.
- meteorology
- Meterology
- Meterological
- meteorlogical
- Study of the atmosphere and its phenomena.
- MFRP
- Mars Fundamental Research Program
- microphysical
- Microphysical
- microphysics
- Microphysics
- The physics of molecules, atoms, and elementary particles.
- MIDEX
- Medium Explorer
- MIDP
- Mars Instrument Development Project
- Milky Way
- milky way
- The galaxy of which the sun and the solar system are a part and which contains the myriads of stars that create the light of the Milky Way.
- mission
- Mission
- Missions
- missions
- NASA Science-funded activity with the purpose of meeting goals laid out by presidential directive, and detailed in Science Mission Directorate's strategic plan.
- mitigate
- Mitigate
- To cause to become less harsh or hostile.
- ML3N
- Mars Long-lived Lander Network
- MMS
- Magnetospheric Multiscale
- modeling
- Modeling
- model
- models
- Models
- A mathematical representation of a process, system, or object developed to understand its behavior or to make predictions. The representation always involves certain simplifications and assumptions.
- MODIS
- Moderate Resolution Imaging Spectrometer
- modulated
- modulate
- modulates
- Modulated
- Modulate
- Modulates
- To vary the amplitude, frequency, or phase of (a carrier wave or a light wave) for the transmission of information (as by radio); to vary the velocity of electrons in an electron beam.
- MU-SPIN
- Minority University-Space Interdisciplinary Network