Yes, absolutely, shielding matters and is especially important for the SAA. ISS-RAD was moved around Station every few months during 2018, which explains part of the variation. And MSL-RAD is under ~ 23 g cm^-2 of CO2, so of course the comparison is not apples to apples. But it’s interesting how it seems to be working out, even if the “agreement” is the product of numerous factors that are sort of conspiring to give such similar results.

 

 

From: Mark D Looper <mark.d.looper@aero.org>
Date: Wednesday, January 9, 2019 at 12:03 PM
To: "Zeitlin, Cary J (JSC-SD2)[WYLE LABORATORIES, INC.]" <cary.j.zeitlin@nasa.gov>, Harlan Spence <spence@guero.sr.unh.edu>
Cc: "crater-team@lists.sr.unh.edu" <crater-team@lists.sr.unh.edu>
Subject: Re: [Crater-team] Link to paper - requires a subscription :-(

 

Is it not also a matter of shielding, in that the LEO SAA spectrum is falling with energy and thus is comparatively easy to shield against, whereas the interplanetary GCR spectrum rises up to very deeply penetrating energies?  What were the assumptions in the paper(s) warning about interplanetary radiation exposure?  The plot you sent is for detectors relatively open to space, right?

 

Mark D. Looper
Space Sciences Department
The Aerospace Corporation
M/S M2-260
P.O. Box 92957
Los Angeles, CA 90009-2957
Mobile: 310-529-3406
Voicemail: 310-336-6302

 

From: Crater-team <crater-team-bounces@lists.sr.unh.edu> on behalf of "Zeitlin, Cary J (JSC-SD2)[WYLE LABORATORIES, INC.]" <cary.j.zeitlin@nasa.gov>
Date: Wednesday, January 9, 2019 at 9:51 AM
To: Harlan Spence <spence@guero.sr.unh.edu>
Cc: "crater-team@lists.sr.unh.edu" <crater-team@lists.sr.unh.edu>
Subject: Re: [Crater-team] Link to paper - requires a subscription :-(

 

 

Good point! Nuance is completely lost in these things.

 

OTOH, the exposure isn’t all that different in LEO, as I’ve been learning since we started getting ISS-RAD data. The geomagnetic field is protective, but in terms of dose, the SAA passes more or less undo the protection. So the difference is mostly that the LEO spectrum is more populated at low-LET than deep space, which is an even greater degree of nuance.

 

 

From: Harlan Spence <spence@guero.sr.unh.edu>
Date: Wednesday, January 9, 2019 at 11:44 AM
To: "Zeitlin, Cary J (JSC-SD2)[WYLE LABORATORIES, INC.]" <cary.j.zeitlin@nasa.gov>
Cc: "crater-team@lists.sr.unh.edu" <crater-team@lists.sr.unh.edu>
Subject: Re: [Crater-team] Link to paper - requires a subscription :-(

 

Hi Cary,

 

   One issue is that the press picked up on this and said that all the prior studies showing that space radiation is a problem is now called into question.  So there’s a bit of damage control for those who didn’t understand the nuances between LEO and deep space exposure.

 

= Harlan

________________________________



Harlan E. Spence



Director, Institute for the Study of Earth,



   Oceans, & Space and Prof. of Physics 
Morse Hall, Room 306 
University of New Hampshire



8 College Road



Durham, NH 03824-3525







Phone: 603-862-0322



Fax:   603-862-1915







http://www.eos.unh.edu/Faculty/Spence
________________________________







On Jan 9, 2019, at 2:37 PM, Zeitlin, Cary J (JSC-SD2)[WYLE LABORATORIES, INC.] <cary.j.zeitlin@nasa.gov> wrote:

 

 

Thanks for the links – I’m glad they did this, even with all the caveats about sample size, etc.

 

From: Crater-team <crater-team-bounces@lists.sr.unh.edu> on behalf of Harlan Spence <spence@guero.sr.unh.edu>
Date: Wednesday, January 9, 2019 at 11:32 AM
To: "crater-team@lists.sr.unh.edu" <crater-team@lists.sr.unh.edu>
Subject: [Crater-team] Link to paper - requires a subscription :-(

 

 

________________________________




Harlan E. Spence




Director, Institute for the Study of Earth,




   Oceans, & Space and Prof. of Physics 
Morse Hall, Room 306 
University of New Hampshire




8 College Road




Durham, NH 03824-3525









Phone: 603-862-0322




Fax:   603-862-1915









http://www.eos.unh.edu/Faculty/Spence
________________________________