NASA / JPL-Caltech / ASU Ars Technica had the opportunity to tour NASA’s Jet Propulsion Laboratory in California this week, matching for a sneak peek at the near-completion Psyche spacecraft. Named after the asteroid it will explore, this ambitious mission is set to launch in August with a Falcon Heavy rocket. Scientists hope that learning more about this unusual asteroid will improve our understanding of planet formation and the early days of our solar system. Discovered in March 1852 by the Italian astronomer Annibale de Gasparis, 16 Psyche is an M-type asteroid (meaning it has a high content of minerals) that revolves around the Sun in the main asteroid belt, with an unusual potato shape. The long-held hypothesis is that the Soul is the exposed metal core of a protoplanet (micro-planet) from the earliest days of our solar system, with the cortex and mantle stripped of a single collision (or multiple collisions) with other objects. In recent years, scientists have concluded that mass and density estimates are inconsistent with an all-metal residue. Rather, a complex mixture of metals and silicates is more likely. Alternatively, the asteroid could once have been a parent body for a particular class of stony iron meteorites, one that dissolved and reassembled into a mixture of metal and silicate. Or maybe it’s an object like 1 Ceres, a dwarf planet in the asteroid belt between the orbits of Mars and Jupiter – other than 16 Psyche may have experienced a period of volcanic iron during cooling, leaving highly enriched metals in these volcanic centers. Magnification / Multiple projections of 16 Souls depicted by the Very Large Telescope. Scientists have long suspected that metal nuclei are hidden deep inside terrestrial planets such as Earth. But these cores are buried too far beneath rocky mantles and crusts for researchers to discover. As the only metal-core body discovered, Psyche provides the perfect opportunity to shed light on how rocky planets in our solar system (Earth, Mercury, Venus and Mars) may have formed. NASA approved the Psyche mission in 2017, intending to send a spacecraft into orbit around the asteroid and collect critical data on its characteristics. Advertising
“Our understanding of what the Soul can be has not changed that much in recent years,” Linda Elkins-Tanton of Arizona State University, lead researcher on the Psyche mission, told Ars. “It must have had a lot of metal, but we never really learned how much. It could be part of a metal core of a tiny planet from the beginning of the solar system, or it could be something that never melted and never formed, but “It has metal mixed in it, like pebbles with rock. We will not really know until we get there.” Various instruments will be on board the Psyche spacecraft to collect this valuable scientific data. There is a multi-spectrum imaging device capable of producing high enough resolution images for scientists to tell the difference between the metallic and silicate (mineral) components of an asteroid. The job of mapping the asteroid’s composition and identifying all the elements falls within a gamma-ray and neutron spectrometer. There is also a magnetometer that will measure and map any remnants of a magnetic field. Finally, a microwave radiocommunication system will also be able to measure the asteroid’s gravitational field by collecting data on its internal structure. Zoom / A tiny model of the Psyche spacecraft. Jennifer Wellett The chassis, made by a satellite company called Maxar Technologies, was delivered last April. It is about the size of a passenger truck and was built largely from commercial, off-the-shelf technology. “Once in space, the spacecraft will use an innovative propulsion device known as Hall propellers to reach the asteroid,” Ars Space editor Eric Berger wrote last year. “This will be the first time a spacecraft has dared deep space using Hall propellers, and without this technology, the Psyche mission would probably not have been possible – certainly not at a cost of just under $ 1 billion.” Here is a little more from Berger about this innovative approach: Advertising
Chemical propulsion engines are ideal for removing rockets from the Earth’s surface when you need an intense burst of energy to get out of the planet’s gravitational well. But chemical rocket engines are not the most efficient engines in the world, as they launch propulsion. And when a spacecraft is in space, there are more fuel efficient means of transportation. NASA has experimented with [solar electric propulsion] technology for a while. The space agency first tested the propulsion technology in the Deep Space 1 mission, which was launched in 1998, and later in the 2007 Dawn mission, which visited Vesta and Ceres in the asteroid belt. These spacecraft used ion propellants. Hall propellers, on the other hand, use a simpler design, with a magnetic field to restrict the flow of the propellant. These propellers were invented in the Soviet Union and later adapted for commercial purposes by Maxar and other companies. Many of the largest geostationary communications satellites today, such as those provided by DirecTV, use Hall launchers to maintain stations. The use of Hall propeller-based technology has enabled mission scientists and engineers to design a smaller and more affordable spacecraft. Each of the Hall propellers in Psyche will generate three times as much thrust as the ion propellers on the Dawn spacecraft and can process twice as much power. This will allow the spacecraft to reach the asteroid Psyche, located in the main belt, in January 2026, after a journey of 3.5 years. The Psyche team tested the twin solar panels in March, connecting the panels to the spacecraft’s hull and unfolding them lengthwise, before storing the panels until the August launch. The five-panel, cross-shaped solar panels are the largest to be installed in the JPL, with an area of ​​800 square feet (75 square meters). They are specially designed to operate in low light conditions, away from the Sun.