Exploration of Mars failed upon impact. Mars 4 flew by the planet at a range of 2200 km returning one swath of pictures and radio occultation data, which constituted the first detection of the nightside ionosphere on Mars. Mars 7 probe separated prematurely from the carrying vehicle due to a problem in the operation of one of the onboard systems (attitude control or retro-rockets) and missed the planet by . In 1964, NASA's Jet Propulsion Laboratory made two attempts at reaching Mars. Mariner 3 and Mariner 4 were identical spacecraft designed to carry out the first flybys of Mars. Mariner 3 was launched
ISIS (space probe instrument) ISIS (space probe instrument) Integrated Science Investigation of the Sun, stylized IS☉IS, is an instrument aboard the Parker Solar Probe, a space probe designed to study the Sun. IS☉IS is focused on measuring energetic particles from the Sun, including electrons, protons, and ions. The parent spacecraft was launched in early August 2018, and with multiple flybys of Venus will study the heliosphere of the Sun from less that 4 million kilometers or less than 9 solar radii. IS☉IS consists of two detectors, EPI-Lo and EPI-Hi, corresponding to detection of relatively lower and higher energy particles. EPI-Lo is designed to detect