Solar probes. Computer artwork of probes (unmanned spacecraft) being used to investigate the Sun. The red swirls may represent the solar wind, a stream of charged particles continuously emitted by the Sun. The probes have radio antennae (dish-shaped) to transmit data from their sensors back to Earth. The probe at lower centre has its solar panels (rectangles) deployed to generate energy from the sunlight. Several solar probes have been launched from Earth and placed in orbit about the Sun.