The chamber dome is removed after NASA’s Interstellar Mapping and Acceleration Probe (IMAP) completed TVAC testing at the agency’s Marshall Space Flight Center in Huntsville, Alabama.
Image Credit: NASA/Johns Hopkins APL/Princeton/Ed Whitman
NASA’s IMAP (Interstellar Mapping and Acceleration Probe) has successfully completed thermal vacuum testing at the agency’s Marshall Space Flight Center in Huntsville, Alabama, as part of its journey toward launch as soon as this fall. As a modern-day celestial cartographer, IMAP will help researchers better understand the boundary of the The bubble-like region surrounding the solar system inflated by the solar wind, shielding the solar system from interstellar radiation., a sort of magnetic bubble surrounding and protecting our Solar System.
NASA’s IMAP (Interstellar Mapping and Acceleration Probe) arrived at the agency’s Marshall Space Flight Center on March 18, 2025, to undergo testing prior to launch. Video Credit: NASA's Goddard Space Flight Center
Thermal vacuum testing is one of the major environmental tests completed before launch, consisting of two parts: thermal balance and thermal cycling.
Thermal balance tests the thermal design of the spacecraft to verify it works correctly. The IMAP mission underwent a series of hot and cold test cases during which the spacecraft is configured in a flight-like operating mode while the test chamber simulates corresponding conditions outside the spacecraft. For each case, the spacecraft stayed in this state for a day or more, allowing the IMAP team to observe the temperatures that the spacecraft settles out to and how its thermal design functions in these conditions, as well as compare that to predictions from the spacecraft’s thermal model.
Thermal cycling tested how IMAP will operate in both hot and cold conditions to verify that all hardware and software functions correctly. In both hot and cold conditions, IMAP went through several tests, including:
- Performance testing of all spacecraft subsystems and instruments
- A week-long mission simulation where the mission operations team practices controlling the spacecraft from the mission operations center as they would in flight
- Timekeeping testing to verify the onboard clock and timekeeping system are accurate at different temperatures
- Radio The number of repetitions per unit time of the oscillations of an electromagnetic wave (or other wave). The higher the frequency, the greater the energy of the radiation and the smaller the wavelength. Frequency is measured in Hertz. compatibility testing with NASA’s A NASA network of radio telescopes used to communicate with spacecraft beyond Earth's orbit.
NASA’s IMAP (Interstellar Mapping and Acceleration Probe) is shown in the The part of the electromagnetic spectrum whose radiation has somewhat greater frequencies and smaller wavelengths than those of ultraviolet radiation. Because x-rays are absorbed by the Earth's atmosphere, x-ray astronomy is performed in space. and Cryogenic Facility chamber after completing TVAC testing at the agency’s Marshall Space Flight Center in Huntsville, Alabama.
Image Credit: NASA/Johns Hopkins APL/Princeton/Ed Whitman
In March, IMAP departed from the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, where engineers integrated IMAP’s instruments, subsystems, and components and ran them through a gauntlet of tests, including shock testing, to ensure mission success. With the completion of the thermal vacuum tests in April, IMAP has now passed all major instrument and spacecraft tests prior to launch. Next, IMAP will travel to the Astrotech Space Operations Facility near NASA’s Kennedy Space Center in Florida, where it will integrate with the launch vehicle and undergo final preparations ahead of launch.
The IMAP mission will study the heliosphere — the Sun’s magnetic bubble that shields our Solar System — to better understand its protective boundary. With 10 instruments built by multiple organizations, the spacecraft will sample, analyze, and map Charged particles (electrons, protons, and other ions) that are moving very fast (high energy). If the particles originate at the Sun, they are known as solar energetic particles (SEPs)., Charged atomic particles moving in space with very high energies and velocities close to the speed of light; most originate beyond the solar system, but some of relatively low energy area produced in solar flares (called Solar Energetic Particles), and some intermediate energy, called anomalous cosmic rays, are produced at the edge of our solar system., and the A stream of charged particles, mostly protons and electrons, that escapes into the Sun's outer atmosphere at high speeds and streams out into the solar system in all directions. streaming toward Earth from the edges of interstellar space. It will also continually monitor The conditions and activity observed in interplanetary space caused by the Sun’s activity, such as solar flares, solar storms, and coronal mass ejections (CMEs). Severe space weather conditions directed towards Earth can impact infrastructure and technology on Earth, as well as satellites, spacecraft, and astronauts in its trajectory. to protect human and robotic space explorers.
Learn more on NASA's IMAP Blog.
Princeton University Professor and Principal Investigator, David J. McComas, leads IMAP with an international team of more than 25 partner institutions. APL is managing the development phase and building the spacecraft and will operate the mission. The IMAP mission is the fifth mission in NASA’s Solar Terrestrial Probes (STP) Program portfolio. The Explorers and The study of the Sun and its connection to the solar system, including the physical processes that occur in the space environment. Projects Division at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the STP Program for the agency’s Heliophysics Division of NASA’s Science Mission Directorate.