Payload Charging Events in the Mesosphere and Their Impact on Langmuir Type Electric Probes

Three sounding rockets were launched from Andøya Rocket Range in the ECOMA campaign in December 2010. The aim was to study the evolution of meteoric smoke particles during a major meteor shower. Of the various instruments onboard the rocket payload, this paper presents the data from a multi-Needle Langmuir Probe (m-NLP) and a charged dust detector. The payload floating potential, as observed using the m-NLP instrument, shows charging events on two of the three flights. These charging events cannot be explained using a simple charging model, and have implications towards the use of fixed bias Langmuir probes on sounding rockets investigating mesospheric altitudes. We show that for a reliable use of a single fixed bias Langmuir probe as a high spatial resolution relative density measurement, each payload should also carry an additional instrument to measure payload floating potential, and an instrument that is immune to spacecraft charging and measures absolute plasma density

On the Short-Term Variability of Turbulence and Temperature in the Winter Mesosphere

Four mesosphere–lower thermosphere temperature and turbulence profiles were obtained in situ within ∼30 min and over an area of about 100 by 100 km during a sounding rocket experiment conducted on 26 January 2015 at Poker Flat Research Range in Alaska. In this paper we examine the spatial and temporal variability of mesospheric turbulence in relationship to the static stability of the background atmosphere. Using active payload attitude control, neutral density fluctuations, a tracer for turbulence, were observed with very little interference from the payload spin motion, and with high precision (%) at sub-meter resolution. The large-scale vertical temperature structure was very consistent between the four soundings. The mesosphere was almost isothermal, which means more stratified, between 60 and 80 km, and again between 88 and 95 km. The stratified regions adjoined quasi-adiabatic regions assumed to be well mixed. Additional evidence of vertical transport and convective activity comes from sodium densities and trimethyl aluminum trail development, respectively, which were both observed simultaneously with the in situ measurements. We found considerable kilometer-scale temperature variability with amplitudes of 20 K in the stratified region below 80 km. Several thin turbulent layers were embedded in this region, differing in width and altitude for each profile. Energy dissipation rates varied between 0.1 and 10 mW kg−1, which is typical for the winter mesosphere. Very little turbulence was observed above 82 km, consistent with very weak small-scale gravity wave activity in the upper mesosphere during the launch night. On the other hand, above the cold and prominent mesopause at 102 km, large temperature excursions of +40 to +70 K were observed. Simultaneous wind measurements revealed extreme wind shears near 108 km, and combined with the observed temperature gradient, isolated regions of unstable Richardson numbers (0Kp∼5)

Mesosphere-Lower-Thermosphere Neutral Density Measurements from Low-cost COTS Accelerometers and Ionization Gauge

Measurements of aerodynamic drag on objects can be used to determine the density of the medium provided other variables are known. The Space and Atmospheric Instrumentation Laboratory launched a midlatitude sounding rocket named SpEED Demon from Wallops Flight Facility in August 2022. Among the instruments onboard were sensitive low-cost MEMS accelerometers allowing for neutral density measurements through the drag technique up to 100km in altitude. In addition to sensitive accelerometers on the main payload, four ejectable subpayloads also carry an accelerometer providing simultaneous multi-point neutral density measurements, akin to a ‘falling cylinder’ experiment. We present the flight performance and results of this drag-based density measurement technique from the SpEED Demon launch. Drag-derived density results are compared with density measurements from an ionization gauge instrument and the MSIS atmospheric model to provide validation of the technique, showing agreement within 10% in the 80-100km altitude range

Spatial and Temporal Variability in MLT Turbulence Inferred from in situ and Ground-Based Observations During the WADIS-1 Sounding Rocket Campaign

In summer 2013 the WADIS-1 sounding rocket campaign was conducted at the Andøya Space Center (ACS) in northern Norway (69° N, 16° E). Among other things, it addressed the question of the variability in mesosphere/lower thermosphere (MLT) turbulence, both in time and space. A unique feature of the WADIS project was multi-point turbulence sounding applying different measurement techniques including rocket-borne ionization gauges, VHF MAARSY radar, and VHF EISCAT radar near Tromsø. This allowed for horizontal variability to be observed in the turbulence field in the MLT at scales from a few to 100 km. We found that the turbulence dissipation rate, ε varied in space in a wavelike manner both horizontally and in the vertical direction. This wavelike modulation reveals the same vertical wavelengths as those seen in gravity waves. We also found that the vertical mean value of radar observations of ε agrees reasonably with rocket-borne measurements. In this way defined 〈εradar〉 value reveals clear tidal modulation and results in variation by up to 2 orders of magnitude with periods of 24 h. The 〈εradar〉 value also shows 12 h and shorter (1 to a few hours) modulations resulting in one decade of variation in 〈εradar〉 magnitude. The 24 h modulation appeared to be in phase with tidal change of horizontal wind observed by SAURA-MF radar. Such wavelike and, in particular, tidal modulation of the turbulence dissipation field in the MLT region inferred from our analysis is a new finding of this work

Payload charging events in the mesosphere and their impact on Langmuir type electric probes

Three sounding rockets were launched from Andøya Rocket Range in the ECOMA campaign in December 2010. The aim was to study the evolution of meteoric smoke particles during a major meteor shower. Of the various instruments onboard the rocket payload, this paper presents the data from a multi-Needle Langmuir Probe (m-NLP) and a charged dust detector. The payload floating potential, as observed using the m-NLP instrument, shows charging events on two of the three flights. These charging events cannot be explained using a simple charging model, and have implications towards the use of fixed bias Langmuir probes on sounding rockets investigating mesospheric altitudes. We show that for a reliable use of a single fixed bias Langmuir probe as a high spatial resolution relative density measurement, each payload should also carry an additional instrument to measure payload floating potential, and an instrument that is immune to spacecraft charging and measures absolute plasma density

Rocket Measurements of Electron Energy Spectra From Earth’s Photoelectron Production Layer

Photoelectrons are crucial to atmospheric physics. They heat the atmosphere, strengthen 28 planetary ambipolar electric fields, and enhance the outflow of ions to space. However, 29 there exist only a handful of measurements of their energy spectrum near the peak of 30 photoproduction. We present calibrated energy spectra of pristine photoelectrons at their 31 source by a prototype Dual Electrostatic Analyzer (DESA) instrument flown on July 11 32 2021 aboard the Dynamo-2 sounding rocket (NASA № 36.357). Photopeaks arising from 33 30.4nm He-II spectral line were observed throughout the flight above 120km. DESA also 34 successfully resolved the rarely observed N2 absorption feature. Below 10eV observations 35 were in good agreement with the GLOW suprathermal electron. Above 10eV fluxes sub36 stantially deviated from the model by as much as an order of magnitude

Balloon Borne GPSsondes that Enable Simultaneous Multi-Point Atmospheric Sensing with a Single Ground Station

Balloon-borne radiosondes provide measurements of in-situ atmospheric data such as wind velocity, temperature, and pressure, amongst many others. The Space and Atmospheric Instrumentation Laboratory at Embry-Riddle Aeronautical University has developed low cost (\u3c $150, all inclusive) GPS-enabled radiosondes that are capable of having multiple balloons simultaneously in the air communicating to a single omni-directional ground station antenna. Each GPS-sonde is equipped with a GPS Module for zonal and meridional winds, thermistor for in-situ temperature, and a pressure sensor. Slant range of greater than 120km is achieved through low-cost LoRa radio modules. Interference-free transmission timing between multiple payloads is done by time division multiplexing. The current design allows for up to six payloads to be simultaneously airborne and transmit live atmospheric data through one ground station. A higher number of simultaneous transmissions are also possible, albeit with a minor hit to spatial resolution. We present the system design, complete with hardware and software details, as well data from our current test flights and plans for future development

Low Cost Magnetometer Calibration and Distributed Simultaneous Multipoint Ionospheric Measurements from a Sounding Rocket Platform

Low cost and low size-weight-and-power magnetometers can provide greater accessibility for distributed simultaneous measurements in the ionosphere, either onboard sounding rockets or on CubeSats. The Space and Atmospheric Instrumentation Laboratory at Embry-Riddle Aeronautical University launched a midlatitude sounding rocket named SpEED Demon from Wallops Flight Facility in August 2022. SpEED Demon has a comprehensive suite of instruments for electrodynamics and neutral dynamics measurements. Among this suite is one high performance Billingsley magnetometer (TFM65VQS) and six commercial-off-the-shelf magnetometers manufactured by the PNI Corporation (RM3100). Of the six, two PNI magnetometers are situated on a deployable boom on the main payload that also carries the Billingsley magnetometer. The remaining four PNI magnetometers are distributed among four ejectable subpayloads. These low-cost and low SWaP magnetometers can achieve a resolution of approximately 1.5 nT and a precision of +/- 4 nT (one sigma) at 15 Hz in a uniform magnetic field. This performance is sufficient for detecting and measuring field aligned currents as well as a variety of other geomagnetic disturbances. The magnetometers are calibrated against an independently calibrated flux-gate magnetometer inside a Helmholtz cage. Zero field offsets are quantified inside a triple-layer mu-metal zero gauss chamber. This work will present the calibration process, the calibration results, and the flight performance of these sensors from the SpEED Demon sounding rocket launch

On the short-term variability of turbulence and temperature in the winter mesosphere

Four mesosphere–lower thermosphere temperature and turbulence profiles were obtained in situ within  ∼ 30&thinsp;min and over an area of about 100 by 100&thinsp;km during a sounding rocket experiment conducted on 26 January 2015 at Poker Flat Research Range in Alaska. In this paper we examine the spatial and temporal variability of mesospheric turbulence in relationship to the static stability of the background atmosphere. Using active payload attitude control, neutral density fluctuations, a tracer for turbulence, were observed with very little interference from the payload spin motion, and with high precision ( &lt; 0.01 %) at sub-meter resolution. The large-scale vertical temperature structure was very consistent between the four soundings. The mesosphere was almost isothermal, which means more stratified, between 60 and 80&thinsp;km, and again between 88 and 95&thinsp;km. The stratified regions adjoined quasi-adiabatic regions assumed to be well mixed. Additional evidence of vertical transport and convective activity comes from sodium densities and trimethyl aluminum trail development, respectively, which were both observed simultaneously with the in situ measurements. We found considerable kilometer-scale temperature variability with amplitudes of 20&thinsp;K in the stratified region below 80&thinsp;km. Several thin turbulent layers were embedded in this region, differing in width and altitude for each profile. Energy dissipation rates varied between 0.1 and 10&thinsp;mW&thinsp;kg−1, which is typical for the winter mesosphere. Very little turbulence was observed above 82&thinsp;km, consistent with very weak small-scale gravity wave activity in the upper mesosphere during the launch night. On the other hand, above the cold and prominent mesopause at 102&thinsp;km, large temperature excursions of +40 to +70&thinsp;K were observed. Simultaneous wind measurements revealed extreme wind shears near 108&thinsp;km, and combined with the observed temperature gradient, isolated regions of unstable Richardson numbers (0 &lt; Ri &lt; 0.25) were detected in the lower thermosphere. The experiment was launched into a bright auroral arc under moderately disturbed conditions (Kp ∼ 5).</p

Observations of Reduced Turbulence and Wave Activity in the Arctic Middle Atmosphere Following the January 2015 Sudden Stratospheric Warming

Measurements of turbulence and waves were made as part of the Mesosphere-Lower Thermosphere Turbulence Experiment (MTeX) on the night of 25–26 January 2015 at Poker Flat Research Range, Chatanika, Alaska (65°N, 147°W). Rocket-borne ionization gauge measurements revealed turbulence in the 70- to 88-km altitude region with energy dissipation rates between 0.1 and 24 mW/kg with an average value of 2.6 mW/kg. The eddy diffusion coefficient varied between 0.3 and 134 m2/s with an average value of 10 m2/s. Turbulence was detected around mesospheric inversion layers (MILs) in both the topside and bottomside of the MILs. These low levels of turbulence were measured after a minor sudden stratospheric warming when the circulation continued to be disturbed by planetary waves and winds remained weak in the stratosphere and mesosphere. Ground-based lidar measurements characterized the ensemble of inertia-gravity waves and monochromatic gravity waves. The ensemble of inertia-gravity waves had a specific potential energy of 0.8 J/kg over the 40- to 50-km altitude region, one of the lowest values recorded at Chatanika. The turbulence measurements coincided with the overturning of a 2.5-hr monochromatic gravity wave in a depth of 3 km at 85 km. The energy dissipation rates were estimated to be 3 mW/kg for the ensemble of waves and 18 mW/kg for the monochromatic wave. The MTeX observations reveal low levels of turbulence associated with low levels of gravity wave activity. In the light of other Arctic observations and model studies, these observations suggest that there may be reduced turbulence during disturbed winters