5 a b s t r a c t 6 Available online xxxx 12 13UV photon-driven condensed phase cosmic ice reactions have been the main focus in understanding the extra-14 terrestrial synthesis of complex organic molecules. Low-energy (≤20 eV) electron-induced reactions, on the 15 other hand, have been largely ignored. In this article, we review studies employing surface science techniques 16 to study low-energy electron-induced condensed phase reactions relevant to astrochemistry. In particular, we 17 show that low-energy electron irradiation of methanol ices leads to the synthesis of many of the same complex 18 molecules formed through UV irradiation. Moreover, our results are qualitatively consistent with the hypothesis 19 that high-energy condensed phase radiolysis is mediated by low-energy electron-induced reactions. In addition, 20 due to the numbers of available low-energy secondary electrons resulting from the interaction of high-energy 21 radiation with matter as well as differences between electron-and photon-induced processes, low-energy 22 electron-induced reactions are perhaps as, or even more, effective than photon-induced reactions in initiating 23 condensed-phase chemical reactions in the interstellar medium. Consequently, we illustrate a need for 24 astrochemical models to include the details of electron-induced reactions in addition to those driven by UV 25 photons. Finally, we show that low-energy electron-induced reactions may lead to the production of unique 26 molecular species that could serve as tracer molecules for electron-induced condensed phase reactions in the 27 interstellar medium. 28 Astrochemistry 31 Low-energy electrons 32 Temperature programmed desorption 33 Infrared reflection absorption spectroscopy 34 Cosmic ices 35 Interstellar medium 36 Synthesis of prebiotic molecules 37 38 39 40 41 45 is filled with complex molecules [2]. In addition to these optical spectral 46 absorption bands, vibrational emission bands have been used to telescop-47 ically identify complex molecules such as polyaromatic hydrocarbons 48 (PAHs Q6 ), fullerenes (C 60 , C 70 ), and diamondoids [3]. Moreover, (sub) mil-49 limeter rotational transitions of molecules have been exploited to identify 50 within interstellar and circumstellar clouds approximately 200 different 51 gas phase molecules including glycolaldehyde (HOCH 2 CHO) [4], a poten-52 tial prebiotic molecule. The synthesis of such complex/prebiotic mole-53 cules in the interstellar medium is thought to occur via three possible 54 mechanisms: (1) gas-phase reactions, (2) surface reactions on bare 55 carbonaceous or silicaceous dust grains, and (3) energetic processing of 56~100 ML (monolayer)-thick ice mantles surrounding micron-sized dust 57 grains [5]. In this review, we will explore the use of surface science tech-58 niques to understand the third mechanism, energetic ice processing, 59 which includes both surface and bulk reactions. Specifically, we will re-60 view the recent work which examines the role of low-energy electrons 61 in the synthesis of prebiot...