Collaborative Study on Solar Wind Conducted by ESA and NASA

As the total solar eclipse approaches, the Solar Orbiter and Parker Solar Probe, both led by ESA and NASA respectively, are taking advantage of their close approach to the Sun to study the plasma that streams from it. These two spacecraft have eccentric orbits, allowing them to get a close-up look at the Sun and then move farther away to recover from the intense heat and radiation. For the first time, both spacecraft will be at their closest approach to the Sun, known as “perihelion,” concurrently. Additionally, their positioning will be at right angles to each other as they observe the Sun. This alignment is significant because it allows Solar Orbiter to capture images of the region on the Sun where the solar wind is produced, which will later hit Parker Solar Probe.

The data collected by both missions will be compared to gain a better understanding of the properties of the solar wind. Since Solar Orbiter is closer to the Sun, its telescopes will observe with higher resolution. Parker Solar Probe, on the other hand, will sample the nearly pristine solar wind a few hours after it has been imaged by Solar Orbiter. This collaboration between the two missions will provide valuable insights into the connection between the Sun and its heliosphere.

One might wonder how Solar Orbiter can observe something that later reaches Parker Solar Probe, given their distance from the Sun. The answer lies in the difference between remote sensing and in situ instruments. Solar Orbiter primarily carries remote sensing instruments, which detect light waves from the Sun at different wavelengths. It takes approximately 2.5 minutes for light to reach Solar Orbiter’s instruments at its closest approach. On the other hand, Parker Solar Probe carries mostly in situ instruments, which directly measure particles and fields in its immediate vicinity. In this case, Parker Solar Probe will measure solar wind particles that travel at speeds of over a million kilometers per hour.

An important goal for the scientists involved in these missions is to observe a coronal mass ejection (CME) heading towards Parker Solar Probe. If successful, they will be able to study the restructuring of the Sun’s outer atmosphere during the CME in great detail and compare these observations with the structure observed in situ by Parker Solar Probe.

This collaboration between Solar Orbiter and Parker Solar Probe extends beyond studying the solar wind. Parker Solar Probe’s instruments are designed to sample the Sun’s corona, providing direct evidence of the conditions of the plasma in that region and how it’s accelerated outwards towards the planets. Solar Orbiter, while pursuing its own scientific goals, will also provide contextual information to imropve the understanding of Parker Solar Probe’s in situ measurements. By working together, the two spacecraft will collect complementary data sets that will generate more scientific insights than either mission could achieve alone.

In addition to its contributions to studying the solar wind, the data collected by Solar Orbiter will also be used to predict the shape of the Sun’s corona during the upcoming total solar eclipse. Researchers from Predictive Science Inc. utilize data from telescopes on and around Earth to create a 3D model of the solar corona. Incorporating data from Solar Orbiter’s Polarimetric and Helioseismic Imager (PHI) instrument for the first time will allow them to include information on the Sun’s magnetic field and improve their predictions.

It is important to note that observing a total solar eclipse requires proper eye protection. Total solar eclipses provide rare opportunities to witness the Sun’s outer atmosphere, which is usually outshone by its brilliant surface. However, wearing appropriate eclipse sunglasses is necessary to avoid eye damage.

The collaboration between Solar Orbiter and Parker Solar Probe during their missions to study the Sun and its effects on the solar system is yielding valuable insights. By using their unique capabilities and data collection methods, these spacecraft are advancing our understanding of the Sun and its impact on our planetary neighborhood.