Planetary Radio: Space Exploration, Astronomy and Science · The Planetary Society

IMAP and the shape of the heliosphere

·57 min·3 clips

IBEX found the unexpected ENA ribbon, and McComas says IMAP will test what plasma physics created it.

Sarah El-Ahmad opens with IMAP and the heliosphere. She introduces the heliosphere as the huge, invisible bubble around the sun and planets, a region that shields us from much of the radiation in the galaxy, and she frames IMAP as the mission built to trace that outer edge from about a million miles from Earth. David McComas joins the discussion. He is the professor of astrophysical sciences at Princeton University and the principal investigator of NASA's IMAP and IBEX missions, and the conversation, with Matias, a professor of astrophysical sciences at MIT, and Martina Gyulidou, quickly shifts from mission basics to the bigger question of how tiny particles can reveal the shape and behavior of the solar system's protective shield. Martina Gyulidou is part of that exchange. She is identified as a heliophysicist at Johns Hopkins Applied Physics Laboratory, former IMAP Ultra instrument lead, and current IMAP project scientist and co-investigator, which keeps the science and the hardware closely tied together. The mission has 10 instruments. Rather than treating them as separate pieces, the show emphasizes that IMAP was built with an infrastructure that lets the data come together quickly, so the team can talk about fundamental physics processes instead of isolated instrument papers. IBEX comes back into the story. McComas says the earlier mission found that high solar wind activity near the sun shows up in the outer heliosphere years later as energetic neutral atoms, or ENAs, and IMAP is meant to carry that work forward with both remote sensing and local solar-wind measurements. L1 matters here. Because IMAP sits about a million miles from Earth, it can sample the solar wind locally while also watching how particles and acceleration processes line up all the way out through the termination shock and beyond. The interview stays patient. Sarah El-Ahmad lets the guests unpack the terms and the architecture of the mission before she closes the hour, and Bruce Betts follows for What's Up.

As heard by us

IMAP turns the heliosphere into a mission with visible edges.

Planetary Radio takes IMAP and turns it into a focused look at the heliosphere, the invisible bubble around the sun and planets that keeps out much of the galaxy's radiation.

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Why you'd press play

You get the heliosphere explained with less fog than the word usually brings.

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