*The bow shock is a region of the heliosphere where the solar wind collides with the interstellar medium.*
*Scientists have long theorized that the heliosphere has a bow shock, but it has never been directly observed.*
*New data from the Interstellar Boundary Explorer (IBEX) spacecraft show that the heliosphere does not have a bow shock.*
*IBEX is a NASA spacecraft that was launched in 2008 to study the boundary between the heliosphere and the interstellar medium.*
*IBEX measures the energetic neutral atoms (ENAs) that are produced when solar wind particles collide with interstellar atoms.*
*The distribution of ENAs around the heliosphere can be used to infer the shape of the heliosphere.*
*The IBEX data show that the heliosphere is not a smooth bubble, but rather has a complex shape with several large-scale bulges and cavities.*
*The absence of a bow shock suggests that the interaction between the solar wind and the interstellar medium is more complex than previously thought.*
*The IBEX data are providing new insights into the nature of the heliosphere and its interaction with the interstellar medium.*
