Enlarge / ESA's Solar Orbiter mission will face the Sun from Mercury's orbit as it approaches it.
ESA / ATG Medialab
Shortly before midnight on Sunday, a spaceship from Cape Canaveral, Florida, launches on a mission to the sun. Known as the Solar Orbiter, this spacecraft will spend the next seven years immersing in and immersing in the extremely inhospitable environment around the sun. This gives us a first look at the poles of the sun, which are crucial for understanding their wrong magnetic field. It will also help uncover the occurrence of violent solar storms that cause plasma to shoot down to earth, where it can turn off satellites and disrupt our electricity grids.
The Solar Orbiter mission is managed by the European Space Agency [ESA] and has been under construction for almost two decades. It complements NASA's Parker Solar Probe, launched in 2018, that will fly closer to the sun than any spacecraft in history. Just a year after starting his mission, Parker is delivering four times more data about the solar environment than expected, says Nour Raouafi, a heliophysicist at John Hopkins University's Applied Physics Laboratory and a Parker project scientist. “We venture into regions of space that we have never explored before,” says Raouafi. "Every observation is a potential discovery."
Solar Orbiter will expand Parker's vast database with a range of 10 instruments, including six that can directly image the sun. This is a luxury that Parker is not able to use, as it gets too close to the sun to image it directly without instantly frying the sensors on a camera. But both Parker and Solar Orbiter are equipped with a range of instruments to study the environment around the sun, such as: B. the magnetic field, the plasma ejections and the irregular eruptions of high-energy particles from the sun's atmosphere or the corona.
Compared to Parker, Solar Orbiter will keep its distance from the sun and never venture closer than about 26 million miles. This is exactly in the orbit of Mercury, a hellish region of the solar system, in which the spaceship suffers temperatures above 900 degrees Fahrenheit while being attacked by high-energy particles that are pushed open by the sun.
Solar Orbiter's hard-hitting instruments are protected from the heat by a shield that is covered with doors that open regularly so that the spacecraft's instruments can image the sun. The Solar Orbiter's heat shield is about half the size of an average parking lot and a mixture of modern and ancient technology. The outermost layer consists of a fraction of a millimeter thick titanium strip, which is coated on the side facing the sun with charred animal bones. This is the same material used by prehistoric people to paint cave walls, but because of its properties, it is also great for radiating heat from a spaceship.
Daniel Verscharen, instrument researcher at Solar Orbiter, is particularly interested in what the ship will reveal about the solar wind, the plasma that continuously flows away from the solar corona. The particles in this plasma can reach speeds of over 1 million miles an hour, but scientists are unsure how the atmosphere of the sun will accelerate them to these high speeds. Solar wind is a constant aspect of space weather, similar to the air temperature on Earth. Sometimes the solar wind is strong, sometimes it is weak, but always in the background.
And just as the earth occasionally hosts extreme weather events, so does the sun. Known as coronal mass ejections, these solar storms can launch more than a billion tons of plasma into space at a speed that makes the solar wind appear slow. This wave of solar material carries its own magnetic field – and if it happens to flow over the earth, it looks like a mallet hitting a gong. When the plasma wave reaches Earth, it ripples in a so-called geomagnetic storm over our own magnetic field.
Earth's atmosphere and magnetosphere defuse the high-energy solar particles and protect us all from cancer when the sun spits plasma. And while the current generated by the colliding magnetic fields flows through the atmosphere, breathtaking aurors emerge, whose blue-green light shimmers over the earth's poles. If the coronal mass ejection is strong enough, it can generate electrical currents on the floor that overwhelm the power grid. Geomagnetic storms can also devastate Earth's GPS satellites by heating the atmosphere, creating drag and causing the satellites to move out of their programmed orbits.
While coronal mass ejections can cause many problems on Earth, they are also of great importance for space agencies that want to send astronauts to the moon or Mars, where they are not protected by a strong magnetic field. If they are hit by one of the sun's plasma waves, they can be exposed to radiation equivalent to 300,000 x-rays at a time – well above the lethal dose of radiation.
"We hope that all of the information we receive from the sun will help us understand the effects of its activity on Earth and protect us a bit better from what is currently quite unpredictable," said Jayne Lefort, research associate at Solar Orbiter Operations Lead at the European Space Agency.
The sun has been a subject of mystery and reverence throughout human history, but with the launch of Solar Orbiter, we're getting a little closer to understanding.
This story originally appeared on wired.com.
