The heliosphere is created by the Sun as a protective bubble of the ionized gas magnetic field that encompasses the entire Solar System. It protects the Earth and other planets from deadly cosmic forces that shape the protective shield.

Now, a team of astrophysicists from different institutions has made a breakthrough discovery that will add to the understanding of how the heliosphere has taken its shape. The team is headquartered at Boston University and led by BU astrophysicist Merav Opher.

(Photo: Wikimedia Commons)
This graphic shows the position of the Voyager 1 and Voyager 2 probes, relative to the heliosphere, a protective bubble created by the Sun that extends well past the orbit of Pluto.


The Heliosphere is Shaped Like a Flattened Croissant

Scientists believe that the heliosphere is a protective bubble created by the Sun to protect the planet within the Solar System from powerful radiation coming out of supernovae when stars in the universe explode, Jerusalem Post reported.

Moreso, they believe that the heliosphere extends beyond the Solar System, providing a massive buffer against cosmic radiation. But no one knows the details of the heliosphere, such as its shape and size.

Although, scientists theorize that it is shaped like a deflated croissant. An academic study in 2020 led by Opher, an Israeli-born astronomy professor, discovered the heliosphere's possible shape. Opher also heads the NASA Diversity, Realize, Integrate, Venture, Educate (DRIVE) Science Center that investigates and develops predictive models of the heliosphere known as the Solar-wind with Hydrogen Ion Exchange and Large-scale Dynamics (SHIELD).

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Neutral Hydrogen Gives the Heliosphere Its Shape

Researchers explain that it is important to study the shape of the heliosphere to understand how it provides protection to the Solar System. There are a lot of theories surrounding how galactic cosmic rays impact the structure of the heliosphere, like whether it has wrinkles and folds.

According to Science Daily, Opher and his team built computer simulations of the heliosphere based on the models built on observable data as well as theoretical astrophysics. They looked for answers to several puzzling questions, like how the heliosphere got its shape, how its ionized particles evolve that affect the processes in the heliosphere, or how the heliosphere interact and influence interstellar medium, and how dos it filters cosmic rays.

Opher said that they combined theory, modeling, and observations to build comprehensive models that work together and help understand the puzzles of this protective bubble.

In the study titled, "A Turbulent Heliosheath Driven by the Rayleigh-Taylor Instability," published in The Astrophysical Journal, they reveal that neutral hydrogen particles from outside the Solar System most likely play a crucial role in the shape of the heliosphere.

According to Tech Explorist, neutral hydrogen has equal amounts of positive and negative charges that create no charge at all. Opher explained that neutral hydrogen comes streaming through the Solar System. They tested the effects of neutrals on the shape of the heliosphere and noticed that the jets coming from the Sun became super stable when they took the neutrals out.

But when put back, it becomes unstable. Scientists theorize that this instability cause disturbance in the solar winds and jets, leading to the split shape pr croissant form of the heliosphere. But astrophysicists have not yet developed ways to observe the heliosphere's actual condition.

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Check out more news and information on the Heliosphere in Science Times.