Indium liquid metal ion sources have been flying for more than 10 years on a variety of spacecraft for spacecraft potential control and as the core element of mass spectrometers. Since 1995, a dedicated indium field emission electric propulsion (In-FEEP) thruster has been under development and recently passed a 2000-h endurance test. The In-FEEP thruster is a micropropulsion device for the 1-100 µN thrust range with low thrust noise and high resolution. The latest performance characteristics including direct thrust measurements and beam profiles are summarized. This information is very important for many upcoming missions that require ultraprecise dragfree control such as the Gravity Field and Steady-State Ocean Circulation Mission, LISA, Terrestrial Planet Finder/Darwin, or SMART-2. Nomenclature c = thrust coefficient factor, % e = elementary charge, 1.6 × 10 −19 C F = force, N g = standard gravitational acceleration, 9.81 m · s −2 I B , I E , I extr , I PS = ion beam, emitter, extractor, plume shield current, A I sp = specific impulse, s m ion = indium ion mass, 1.906 × 10 −25 kg m R = reservoir mass, kġ m ion ,ṁ droplet ,ṁ = ion, droplet, total mass flow rate, kg · s −1 r = emitter-accelerator distance, m U B , U E = extractor bias, emitter voltage, V v = velocity, m · s −1 η m = mass efficiency, % τ = temperature, K

This paper presents the results of a series of tests performed on a set of field emission electric propulsion (FEEP) emitters, including recording of the current/voltage characteristic curves and ion beam scanning with electrostatic probes, This work was aimed at collecting reliable, systematic thruster performance data to be used as a basis for the definition of a reference thruster mathematical model (not reported here). Four FEEP emitters with three different slit height values were tested. Thrust produced covered the 1-170 uN range. Repeatability of thruster performance was found to depend on the degree of wetting of the emitter slit and on the presence of glow discharge between the electrodes. The latter represented an undesired effect and was therefore eliminated after the first series of experiments. Wetting, on the contrary, proved to be of the utmost importance. In some cases, thruster performance improved by up to as much as 150% within a few days of the beginning of the test, as a result of enhanced slit wetting

This article examines the morphological features of the dog during the Roman Age on the basis of osseous and dental remains dug up in Pompeii. The material, consisting of 113 canine bones and teeth, was subjected to both morphological and morphometrical analyses and was compared with modern canine breeds. In most cases, the age at death, shoulder height and other phenotypic features were ascertained. The examined Pompeian canine population fell mainly into two categories: small- and large-sized animals. Among the former, one brachycephalic and two dolichocephalic subjects were included. Such morphological features agree with what is described in numerous texts and appears in mosaics, bas-reliefs and frescoes of the Roman Age. As small-sized dogs cannot be classified as Canes Venatici (sporting dogs), Canes Villatici (watch dogs) and Canes Pastorales (shepherd dogs) according to Columella's De re rustica, these animals may be considered as lapdogs.

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