IAS Gyan

Daily News Analysis

IBEX

10th March, 2023 Science and Technology

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Context

  • NASA is reviving a 15-year-old IBEX probe after a recent system reset.

About the probe IBEX

  • Interstellar Boundary Explorer (IBEX) was launched in 2008 to map the edge of the solar system - the outer edge of the heliosphere, focusing on the "bubble" that represents the boundary between the sun's environment and interstellar space.
  • Engineers equipped it with two energetic neutral atom (ENA) imagers, IBEX-Hi and IBEX-Lo. Both instruments allow the probe to collect and separate ions of different energy levels.
  • IBEX forms part of a network of spacecraft studying the solar wind (or constant stream of particles from our sun) alongside the sun itself to gain a better understanding of how the heliosphere shapes our solar system.

Findings

  • The spacecraft fully mapped the heliosphere in its first year after launch and gets entire-sky images every six months. Its most famous discovery is uncovering a dense region of particles, nicknamed the "IBEX ribbon."
  • During its lifetime, IBEX has reported that the heliosphere has no bow shock, an area of higher density and energy where the sun’s magnetic field encounters interstellar plasma.
  • It also found the relative speed of the heliosphere was 23.2 km/s, about half of the previous estimates. In 2013, IBEX revealed the heliosphere has a four-lobed tail on its trailing end.
  • In 2008, NASA only needed IBEX to last for two years, but it has long since surpassed that. As it comes up on 15 years in space, IBEX is still ready to make discoveries about the border of our solar system.

 

 

HELIOSPHERE

The heliosphere is the magnetosphere and outermost atmospheric layer of the Sun. It takes the shape of a vast, bubble-like region of space. It is the cavity formed by the Sun in the surrounding interstellar medium. The "bubble" of the heliosphere is continuously "inflated" by plasma originating from the Sun, known as the solar wind. As part of the interplanetary magnetic field, the heliosphere shields the Solar System from significant amounts of cosmic ionizing radiation; uncharged gamma rays etc.

HELIOPAUSE

Heliopause marks the end of a region created by our sun that is called the heliosphere. At heliopause the interstellar medium and solar wind pressures balance.

TERMINATION SHOCK

The termination shock is the boundary marking one of the outer limits of the Sun's influence and is one boundary of the solar system. It is where the bubble of solar wind particles slows down so that the particles are traveling slower than the speed of sound.

HELIOSHEATH

The "heliosheath", is a broad transitional region between the termination shock and the heliosphere's outmost edge, the "heliopause".

PRELIMS PRACTICE QUESTION

Q. Choose the correct answer with reference to the following statements.

A.    Interstellar Boundary Explorer (IBEX) was launched in 2008 by European Space Agency to map the edge of the solar system.

B.    During its lifetime, IBEX has reported that the heliosphere has no bow shock, an area of higher density and energy where the sun’s magnetic field encounters interstellar plasma.

1) A only

2) B only

3) Both A and B

4) Neither A nor B

Answer: 2

 

https://www.space.com/nasa-ibex-flight-computer-normal-march-2023