The Solar System may be enveloped in a bubble of space, which can sometimes become wrinkled.
Data from a spacecraft orbiting Earth has revealed ripple structures in the termination shock and heliopause: shifting regions of space that mark one of the boundaries between the space inside the Solar System, and what’s outside – interstellar space.
These results demonstrate that it is possible to see the boundaries of the Solar System in detail and how they change over time.
This information will allow scientists to better understand the heliosphere. It is a region of space that pushes out from our Sun and shields the planets within the Solar System from cosmic radiation.
There are many ways in which the Sun influences the surrounding space. One such way is the solar wind. This supersonic flow ionized plasma in a continuous stream is one example. It blows past planets and through the Kuiper Belt before eventually reaching the vast void between stars.
The moment at which the flow is below the speed sound waves can travel through diffuse interstallar media is known as the Termination shockThe point at which it can no longer resist the slight pressure of interstellar spaces is called the heliopause.
Both Voyager probes are available. Crossed the heliopauseThey are now effectively cruising through interstellar Space, providing us with the first in situ measurements for this shifting boundary. NASA’s Interstellar Boundary Explorer (NASA) is another tool that scientists use to map the heliopause. It was launched in 2009 and has been in operation since then.IBEX).
IBEX is an indicator of energized neutral Atoms. These atoms are formed when the Sun’s solar winds collide with interstellar winds at the Solar System boundary. Some of these atoms are sent further into space while others are returned to Earth. When the strength of solar wind which produced them is considered, The return of energized neutron particles can be used to map out the boundary’s shape, much like cosmic echolocation.
Maps of the structure and evolution of the solar wind pressure, and the energetic neutral atom emission have been used to map the heliosphere’s structure in the past. This allowed for a smoothing of both time and space. Over a period of approximately six months, however, the dynamic solar wind pressure increased by about 50 percent.
A team of scientists led by astrophysicist Eric Zirnstein of Princeton University has used this shorter-scale event to obtain a more detailed snapshot of the shape of the termination shock and heliopause – and found huge ripples, on the scale of tens of astronomical units (one astronomical unit is the average distance between Earth and the Sun).
They also did simulations and modeling to see how the high-pressure wind acted on the Solar System boundary. They discovered that the pressure front reached 2015’s termination shock, sending a pressure wave through a region known as the inner Heliosheath between the termination shock & the heliopause.
A reflected wave travels back to the heliopause and collides with the still-incoming flow charged plasma behind the pressure front. This creates a storm of energetic neutron atoms which fills the inner Heliosheath when the reflected waves arrives back at the termination shocked.
Also, the measurements of the team show a marked shift in the distance to heliopause. Voyager 1 reached the heliopause at a distance in 2012 of 122 astronomical unit. 2016: The team measured the distance to Voyager 1’s heliopause at 131 astronomical Units. In 2012, Voyager 1 was located at 136 astronomical Units from the sun.
The measurement of the heliopause by the team in Voyager 2’s direction in 2015 is more complicated. It was calculated in 103 astronomical Units with an error margin 8 astronomical Units. Voyager 2 was still within the error margin at 109 astronomical unit distance from the Sun. It crossed the heliopause in 2018 at a distance astronomical units of 119.
Both measurements indicate that the shape and size of the heliopause change, and it is not insignificant. It is not clear why.
In 2025, however, a new probe to space will be launched to measure energetic neutron emission with greater precision and over a wider energy spectrum. The team believes that this will answer many of the puzzles about the bizarre, invisible, and ‘wrinkly bubble that protects our little planetary systems from the strangeness in space.
The research was published in Astronomy of Nature.
