International Journal of Mass Spectrometry 295 (2010) 124–132 Contents lists available at ScienceDirect International Journal of Mass Spectrometry journal homepage: www.elsevier.com/locate/ijms Development of an evolved gas-time-of-flight mass spectrometer for the Volatile Analysis by Pyrolysis of Regolith (VAPoR) instrument Stephanie A. Getty a,∗ , Inge L. ten Kate a,b , Steven H. Feng a , William B. Brinckerhoff a , Eric H. Cardiff a , Vincent E. Holmes a,c , Todd T. King a , Mary J. Li a , Erik Mumm d , Paul R. Mahaffy a , Daniel P. Glavin a a NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771, USA b Goddard Earth Science and Technology Center, 5523 Research Park Drive, Suite 320, University of Maryland Baltimore County, Baltimore, MD 21228, USA c Bastion Technologies, 7535 Mission Drive, Lanham, MD 20706-2291, USA d Honeybee Robotics, 460W. 34th Street, New York, NY 10001, USA article info Article history: Received 9 April 2010 Received in revised form 17 June 2010 Accepted 18 June 2010 Available online 30 June 2010 Keywords: Time-of-flight Pyrolysis Planetary science Mass spectrometry Field emission Carbon nanotube abstract Low power, robust technologies are appealing for in situ planetary science throughout the Solar System. The VAPoR (Volatile Analysis by Pyrolysis of Regolith) instrument is under development toward studying soil composition, volatiles, and trapped noble gases in the polar regions of the Moon and on the surface of other airless bodies. VAPoR will ingest a soil sample and conduct analysis by pyrolysis and time-of-flight mass spectrometry (ToF-MS). Two components of the system have been characterized in parallel devel- opment: a field-tested sample heater design and a laboratory-based time-of-flight mass spectrometer that emphasizes reduced mass and power through the use of micro- and nanotechnology. The pyrolysis field unit, vacuum-coupled to a commercial residual gas analyzer, has been used in Hawaii to analyze Mauna Kea soils. Water was detected, as were key inorganic pyrolysis products, including CO 2 and SO 2 , and organic volatiles, including methane, benzene, toluene, and various hydrocarbon fragments. In paral- lel development, a laboratory reflectron time-of-flight mass spectrometer has been designed, assembled, and tested using electron impact ionization from a carbon nanotube electron gun. Preliminary testing reveals a mass resolution of 270. Published by Elsevier B.V. 1. Introduction Measuring the chemical composition of solid bodies in our Solar System is key to understanding the formation and evolution of the planets and their moons. One possible instrument for in situ chemi- cal analysis of planetary atmospheres and surface regolith is VAPoR, Volatile Analysis by Pyrolysis of Regolith [1]. As part of a landed or roving mission to the surface of a solid body, VAPoR enables compo- sitional and isotopic measurements of volatiles released from solid surface samples on airless bodies including the Moon, asteroids, comets, and the icy moons of the Outer Planets. With the addition of a miniature turbo-pump, VAPoR could also operate in higher ∗ Corresponding author at: NASA Goddard Space Flight Center, Materials Engi- neering Branch, Mailstop 541.0, Greenbelt, MD 20771, USA. Tel.: +1 301 286 9760. E-mail addresses: stephanie.a.getty@nasa.gov (S.A. Getty), inge.l.tenkate@nasa.gov (I.L. ten Kate), steven.h.feng@nasa.gov (S.H. Feng), william.b.brinckerhoff@nasa.gov (W.B. Brinckerhoff), eric.h.cardiff@nasa.gov (E.H. Cardiff), vincent.holmes@nasa.gov (V.E. Holmes), todd.t.king@nasa.gov (T.T. King), mary.j.li@nasa.gov (M.J. Li), mumm@honeybeerobotics.com (E. Mumm), paul.r.mahaffy@nasa.gov (P.R. Mahaffy), daniel.p.glavin@nasa.gov (D.P. Glavin). pressure environments including Mars and Titan. As depicted in Fig. 1, VAPoR combines a sample carousel of 6 individually heated pyrolysis ovens with a miniaturized, low-power and low-mass time-of-flight mass spectrometer (ToF-MS). Powdered or ground soil samples collected by a rover or lander sample acquisition system and delivered to the VAPoR ovens can be heated to temper- atures up to 1200 ◦ C to liberate the volatile constituents for direct measurement by the ToF-MS. Two independent units have been built and tested to understand the performance of the different instrument components. A laboratory breadboard was developed to test and calibrate the ToF-MS, and a portable field unit consist- ing of a custom made high temperature pyrolysis oven, coupled to a commercial RGA mass spectrometer via a vacuum system, was built to demonstrate the feasibility of conducting vacuum pyrolysis evolved gas measurements in the field. Calibration of the VAPoR field unit can help to identify the bulk chemistry of the soil samples, including the presence of water, hydrocarbons, noble gases, and evolved gas signatures correspond- ing to carbonates, sulfates, and nitrates. Evidence for aqueous alteration and the presence of water and hydrocarbons in planetary regolith will provide insight into the occurrence of astrobiology- 1387-3806/$ – see front matter. Published by Elsevier B.V. doi:10.1016/j.ijms.2010.06.020