Solar Sentinels

The Solar Sentinels was a proposed space mission to Sun. Solar Sentinels was proposed in 2006 in conjunction with other Sun missions, and a Solar Sentinels lite was proposed in 2008.

It might have studied the Sun during its solar maximum, the last before the beginning of the Orion program. Six spacecraft will be launched, which will separate into three groups. The Solar Sentinels are part of the NASA program Living With a Star.

The goals of the Solar Sentinels are:

This mission's driving energy is that the solar maximum of solar cycle 24 will be the final one before the first upcoming manned missions to the Moon and Mars. This means that this will be the last chance to understand the solar storms and the deadly radiation of a solar maximum.

There will be six spacecraft: four identical spacecraft which will explore the inner heliosphere, one spacecraft which will take its post near Earth, and the final sentinel to trail slowly behind Earth. They are discussed in greater detail below.

The majority of the sentinels are the Inner Heliospheric Sentinels (IHS), which will observe the Sun at distances of 0.25 AU. This will be a challenge to scientists and engineers working on these probes, as this is one-fourth the distance between the Earth and the Sun. These probes will make in-situ measurements of energetic particles and plasma. Instruments to measure X-ray, radio, and neutron emissions will be included. Part of the mission plan includes Venus flybys.

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