page_title: Solar Orbiter
hierarchical_section_title: Solar Orbiter
context_page_description: The Solar Orbiter is a Sun-observing satellite, developed by the European Space Agency. SolO is intended to perform detailed measurements of the inner heliosphere and nascent solar wind, and perform close observations of the polar regions of the Sun, which is difficult to do from Earth, both serving to answer the question "How does the Sun create and control the heliosphere?"
  SolO makes observations of the Sun from an eccentric orbit moving as close as ≈60 solar radii, or 0.284 astronomical units, placing it inside Mercury's perihelion of 0.3075 au. During the mission the orbital inclination will be raised to about 24°. The total mission cost is US$1.5 billion, counting both ESA and NASA contributions.
  SolO was launched on 10 February 2020. The mission is planned to last 7 years.
context_section_description: The Solar Orbiter (SolO) is a Sun-observing satellite, developed by the European Space Agency (ESA). SolO is intended to perform detailed measurements of the inner heliosphere and nascent solar wind, and perform close observations of the polar regions of the Sun, which is difficult to do from Earth, both serving to answer the question "How does the Sun create and control the heliosphere?"
  SolO makes observations of the Sun from an eccentric orbit moving as close as ≈60 solar radii (RS), or 0.284 astronomical units (au), placing it inside Mercury's perihelion of 0.3075 au. During the mission the orbital inclination will be raised to about 24°. The total mission cost is US$1.5 billion, counting both ESA and NASA contributions.
  SolO was launched on 10 February 2020. The mission is planned to last 7 years.
caption: A comparison of the size of the Sun as seen from Earth (left, 1 au) and from the Solar Orbiter spacecraft (0.284 au, right).