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The Parker Solar Probe (PSP or Parker Probe, earlier known as the Solar Probe, Solar Probe Plus, and Solar Probe+) is a spacecraft launched in 2018 to observe the corona of the Sun from near the corona's outer reaches. It is in an eccentric solar orbit which will be tweaked through Venus flybys as the mission proceeds, to further reduce the perihelion. In January 2021, the probe passed closer to the Sun than any previous spacecraft, roughly 0.1 AU. Instruments:
Close approaches during the mission (distances from the center of the Sun):
| solar radii | million km | AU | |
| PSP perihelion, 1/2021 | 20.3 | 14.1 | 0.09 |
| PSP perihelion, 1/2022 | 13.3 | 9.3 | 0.062 |
| PSP perihelion, eventual goal | 9.9 | 6.9 | 0.046 |
| for comparison: | |||
| solar radius | 1 | 0.696 | 0.00465 |
| corona (cited values vary) | 6 | 4.2 | 0.0279 |
| Venus's orbit | 156 | 108.2 | 0.72 |
| Mercury's orbit | 83 | 57.9 | 0.387 |
(Another source cited the corona as extending twice that far, clearly beyond the Parker Probe's nearest encounters.)