The 2015 Earth-Orbiting Heliophysics Fleet

The satellite orbits are color coded for their observing program:

• Magenta: TIM (Thermosphere, Ionosphere, Mesosphere) observations
• Yellow: solar observations and imagery
• Cyan: Geospace and magnetosphere
• Violet: Heliospheric observations

Near-Earth Fleet:

• Hinode: Observes the Sun in multiple wavelengths up to x-rays. SVS page
• RHESSI : Observes the Sun in x-rays and gamma-rays. SVS page
• TIMED: Studies the upper layers (40-110 miles up) of the Earth's atmosphere.
• CINDI: Measures interactions of neutral and charged particles in the ionosphere.
• SORCE: Monitors solar intensity across a broad range of the electromagnetic spectrum.
• AIM: Images and measures noctilucent clouds. SVS page
• Van Allen Probes: Two probes moving along the same orbit designed to study the impact of space weather on Earth's radiation belts. SVS page
• TWINS: Two Wide-Angle Imaging Neutral-Atom Spectrometers (TWINS) are two probes observing the Earth with neutral atom imagers.
• IRIS: Interface Region Imaging Spectrograph is designed to take high-resolution spectra and images of the region between the solar photosphere and solar atmosphere.

Geosynchronous Fleet:

• SDO: Solar Dynamics Observatory keeps the Sun under continuous observation at 16 megapixel resolution.

Geospace Fleet:

• Geotail: Conducts measurements of electrons and ions in the Earth's magnetotail.
• Magnetospheric Multi-scale (MMS): This is a group of four satellites which fly in formation to measure how particles and fields in the magnetosphere vary in space and time. SVS page
• THEMIS: This is a fleet of three satellites to study how magnetospheric instabilities produce substorms. Two of the original five satellites were moved into lunar orbit to become ARTEMIS. SVS page
• IBEX: The Interstellar Boundary Explorer measures the flux of neutral atoms from the heliopause.

Lunar Orbiting Fleet:

• ARTEMIS: Two of the THEMIS satellites were moved into lunar orbit to study the interaction of the Earth's magnetosphere with the Moon.

• MMS added
• GOES satellites removed
• Cluster satellites removed
• Camera moves around the night-side of Earth
.