Posted on by Mark Thompson

NASA Announces a New Class of Space Missions: Probe Explorers

NASA has sent a whole host of spacecraft across the Solar System and even beyond. They range from crewed ships to orbit and to the Moon to robotic explorers. Among them are a range of mission classes from Flagships to Discovery Class programs. Now a new category has been announced: Probe Explorers. This new category will fill the gap between Flagship and smaller missions. Among them are two proposed missions; the Advanced X-ray Imaging Satellite and the Probe Far-Infrared Mission for Astrophysics. 

NASA’s new Probe Explorers program aims to cultivate creative ideas to explore the Universe. The category is one of the largest astrophysics program from the American space agency. Nicola Fox, NASA’s associate administrator of Science Mission Directorate said of the category ‘..it has taken creativity to new heights,’ adding ‘selected concepts could enable ground breaking science responsive to the top astrophysics priorities of the decade, develop key technologies for future flagship missions, and offer opportunities for the entire community.’

The two projects that have been proposed are now due for additional scrutiny. They will each received $5million to undertake a 12 month concept study. After this period, a detailed evaluation will be undertaken to select one of the proposals in 2026 to launch in 2032. The chosen mission will become the first of NASA’s Probe Explorer program.

The Advanced X-ray Imaging Satellite is planned to be a large, flat field-of-view giving a high level of spatial resolution. It’s perfectly suited to the study of supermassive black holes and how galaxies evolve. It’s principle investigator Christopher Reynolds from the University of Maryland is keen to see it build on the results of previous X-ray observatories in understanding the power sources of a number of violent events across the Universe. 

This image shows Hercules A, a galaxy in the Hercules constellation. The X-ray observations show superheated gas, and the radio observations show jets of particles streaming away from the AGN at the center of the galaxy. The jets are almost 1 million light-years long. Image Credits: X-ray: NASA/CXC/SAO; visual: NASA/STScI; radio: NSF/NRAO/VLA.

The other mission in with a chance of the 2032 launch is the Probe Far-Infrared Mission for Astrophysics. The observatory would be a 1.8 metre telescope designed to study the far-infrared radiation that is permeating space. The James Webb Space Telescope has an infrared capability but this new proposal will help to cover the electromagnetic spectrum which is between the JWST and radio telescopes.  Managed by the Jet Propulsion Laboratory, it will attempt to answer questions about the origins of planets, of supermassive black holes, stars and cosmic dust. 

Annotated image of Digel Cloud 2S captured by Webb’s NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument), with compass arrows, a scale bar, colour key, and graphic overlays for reference. The north and east compass arrows show the orientation of the image on the sky. Note that the relationship between north and east on the sky (as seen from below) is flipped relative to direction arrows on a map of the ground (as seen from above). The scale bar is labelled in light-years and arcseconds. One light-year is equal to about 9.46 trillion kilometres. One arcsecond is equal to 1/3600 of one degree of arc (the full Moon has an angular diameter of about 0.5 degrees). The actual size of an object that covers one arcsecond on the sky depends on its distance from the telescope. This image shows invisible near- and mid-infrared wavelengths of light that have been translated into visible-light colours. The colour key shows which NIRCam and MIRI filters were used when collecting the light. The colour of each filter name is the visible light colour used to represent the infrared light that passes through that filter. In the main cluster are five white arrows, which highlight the paths of five protostar jets.

The Explorers Program launched in 1958 and the Probe Explorer is just a small part is this the oldest NASA program still running today. Its main objective is to provide low cost access to space with frequent launches. Missions are science led and must be relevant to NASA’s Science Mission Directorate’s astrophysics and heliophysics program. There has been significant success from the Explorers Program in the decades since its inception from the discovery of the Earth’s radiation belts to the launch of more than 90 science led missions.

Source : NASA Establishes New Class of Astrophysics Missions, Selects Studies