ST. GEORGE — A spacecraft headed to Mercury made a flyby past Earth on Friday as it completed a crucial maneuver.
The maneuver was part of the spacecraft’s seven-year journey to the nearest planet to the Sun, a rocky world that plays an important role in revealing how the inner planets were formed and what conditions emerged to sustain life on Earth more than 4 billion years ago.
The spacecraft, dubbed “BepiColombo,” is part of a joint mission between the European Space Agency and the Japanese Aerospace Exploration Agency and whizzed by Earth at an altitude of nearly 7,900 miles above the planet’s surface as it continued along its complicated path to Mercury.
One goal of the mission is to help scientists understand how Mercury — and, in turn, the entire solar system — formed.
The spacecraft was launched in 2018 on an Arien 5 rocket, a heavy-lift rocket that stands more than five stories high.
This is the first mission of its kind for the European Space Agency, as all previous interplanetary endeavors involved sending spacecraft and probes to the outer planets orbiting along the outskirts of the solar system millions of miles from Earth.
Instead, the joint endeavor is sending a spacecraft in the opposite direction as it hurtles toward the innermost planet, which is roughly 40 million miles from the sun.
The payload consists of two scientific orbiters, the first of which is a planetary orbiter to map Mercury at different wavelengths as it charts the planet’s mineralogy and elemental composition. The second, a magnetospheric orbiter, will be used to determine whether the interior of the rocky planet is molten or not. The equipment will also be used to analyze Mercury’s magnetic field, a phenomenon that remains confusing for scientists even today.
BepiColombo is a particularly challenging mission, the space agency says, in that Mercury is so small and so close to the sun. It orbits incredibly fast, so any spacecraft visiting the innermost planet has to travel at break-neck speeds in order to catch up to it as it whizzes around the center of our solar system.
At the same time, the spacecraft will be pulled inward by the sun’s massive gravity, so it will need to apply the brakes as it hurtles toward its destination so it can fall into a stable orbit instead of getting tugged off course.
Friday’s maneuver was at an angle designed to slightly reduce the spacecraft’s speed with respect to the sun, an adjustment which allowed BepiColombo to head deeper into the solar system. The arduous path to Mercury requires nine planetary encounters with Earth, Venus and Mercury which will slow the spacecraft down before it slips into orbit around the rocky planet in 2025, according to the European Space Agency.
BepiColombo will use the gravity of Earth, Venus and Mercury in combination with the thrust provided by electric propulsion powered by the sun. The probe will loop around Venus twice in order to further reduce its speed and put itself on track to meet its target.
The mission is scheduled to continue for at least one year and may be extended.
The first missions to Mercury – NASA’s Mariner 10 and Messenger
The first mission to Earth’s tiny neighbor took place more than 50 years ago, when NASA sent the first probe, Mariner 10. The probe performed three separate passes of the planet between 1974-1975 as it studied the surface and physical characteristics of Mercury. Using the gravity of Venus, the probe was propelled toward the innermost planet during the first of three trips around Mercury. During the final approach, Mariner came within 200 miles of the planet’s surface, NASA says.
The Mariner mission accomplished a number of firsts, including the first to use the solar wind as a major means of spacecraft orientation during flight, the first to visit two planets during the same mission and the first to use gravity assist to change its flight path – a mechanism that is still in use today.
In August 2004, NASA’s Messenger probe was launched on its four-year journey to reach the rocky planet, making its first flyby in 2008. Messenger became the second mission to reach Mercury as it orbited the planet from March 2011 until it was intentionally sent plunging into the surface of Mercury at more than 8,750 mph on April 30, 2015, creating a crater that was roughly 52 miles across.
While the crater is not visible from Earth, it will be visible to the BepiColombo probe, and its instruments will be able to study the crater left in the wake of the doomed spacecraft.
Copyright St. George News, SaintGeorgeUtah.com LLC, 2020, all rights reserved.