Solar Orbiter Rises to Uncover the Secrets of Our Star

Featured Image: A “streak shot” of the launch of Solar Orbiter from Cape Canaveral (Image credit: Next Horizons Spaceflight/Stephen Marr)

CAPE CANAVERAL, FLORIDA – In a joint effort, NASA and ESA have launched the first major solar science mission of the 2010s and first since the Parker Solar Probe was launched in 2018.

At 11:03 pm EST Feb. 9th (0403 Feb 10 UTC), a ULA Atlas V booster rocketed off from Cape Canaveral, Florida carrying the Solar Orbiter (SolO) probe on its journey to study the Sun.

The SolO mission is being run by ESA, with NASA providing launch and support services through ULA. The SolO mission is slated to last 7.5 years, with a possible mission extension to 9.5 years. The first 3.5 years of the mission will be spent in the “cruise phase” as SolO makes its way to a highly elliptical heliospheric (Sun-centered) orbit. The planned trajectory will make use of several gravitational assists by both Earth and Venus over the cruise phase, during which time SolO will be providing valuable in situ science data about solar wind and the heliosphere. The science mission phase will be entered once SolO reaches an orbit with a perihelion (closest approach to the sun) of 0.28 AU (26 million miles) and an aphelion (farthest point from the sun) of 0.92 AU (85.6 million miles). During the cruise phase, SolO will use Venus gravity assists to place itself into an off-ecliptic inclination of 25 degrees, which will be raised to 34 degrees in the extended mission.

Solar Orbiter will fly in a complex series of orbits using Venus and Earth flybys to assist in reaching its final science orbit. (Image credit: ESA)

The goal of these orbital parameters is to place SolO into a co-rotating orbit with the sun, orbiting at the same rate the sun rotates. The inclination of this orbit is to provide the first ever views of the solar polar regions. It is hoped these views will provide new data as to the way the Sun generated the heliosphere, or region in which solar wind provides the majority of influence. The heliosphere protects the solar system from intergalactic cosmic rays. The mission is designed to study how the solar wind is generated and how the Sun generates it own internal dynamo, or magnetosphere.

The main hope for scientists is to understand how solar wind is generated and how this affects space weather. This is important to life on Earth as there are currently very limited ways to predict solar activity. Understanding the Sun’s 11-year cycle has been a goal of heliophysic scientists for quite some time, and this understanding may help with forecasting solar weather in the future. As with all science, any data obtained will provide better modeling and better understanding. The new data may answer many questions, but it will also spurn new questions that future missions will address.