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NASA NTRS2010

Luminous Efficiency of Hypervelocity Meteoroid Impacts on the Moon Derived from the 2006 Geminids, 2007 Lyrids, and 2008 Taurids

Since early 2006 the Meteoroid Environment Office at NASA's Marshall Space Flight Center has been consistently monitoring the Moon for impact flashes produced by meteoroids striking the lunar surface. During this time, several meteor showers have produced multiple impact flashes on the Moon. The 2006 Geminids, 2007 Lyrids, and 2008 Taurids were observed with average rates of 5.5, 1.2, and 1.5 meteors/hr, respectively, for a total of 12 Geminid, 11 Lyrid, and 12 Taurid lunar impacts. These showers produced a sufficient, albeit small sample of impact flashes with which to perform a luminous efficiency analysis similar to that outlined in Bellot Rubio et al. for the 1999 Leonids. An analysis of the Geminid, Lyrid, and Taurid lunar impacts is carried out herein in order to determine the luminous efficiency in the 400-900 nm wavelength range for each shower. Using the luminous efficiency, the kinetic energies and masses of these lunar impactors can be calculated.

Moser, D. E.↗
NASA NTRS2010

Lunar Meteoroid Impact Observations and the Flux of Kilogram-Size Meteoroids

Meteor showers dominate the environment in this size range and explain the evening/morning flux asymmetry of 1.5:1. With sufficient numbers of impacts, this technique can help determine the population index for some showers. Measured flux of meteoroids in the 100g to kilograms range is consistent with other observations. We have a fruitful observing program underway which has significantly increased the number of lunar impacts observed. Over 200 impacts have been recorded in about 4 years. This analysis reports on the 115 impacts taken under photometric conditions during the first 3 full years of operation. We plan to continue for the foreseeable future as follows: 1) Run detailed model to try explain the concentration near the trailing limb; 2) Build up statistics to better understand the meteor shower environment; 3) Provide support for robotic seismometers and dust missions; and 4) Deploy near-infrared and visible cameras with dichroic beamsplitter to 0.5m telescope in New Mexico.

Suggs, Rob↗
NASA NTRS2010

Luminous Efficiency of Hypervelocity Meteoroid Impacts on the Moon Derived from the 2006 Geminids, 2007 Lyrids, and 2008 Taurids

Since early 2006 the Meteoroid Environment Office (MEO) at NASA s Marshall Space Flight Center has been consistently monitoring the Moon for impact flashes produced by meteoroids striking the lunar surface. During this time, several meteor showers have produced multiple impact flashes on the Moon. The 2006 Geminids, 2007 Lyrids, and 2008 Taurids were observed with average rates of 5.5, 1.2, and 1.5 meteors/hr, respectively, for a total of 12 Geminid, 12 Lyrid, and 12 Taurid lunar impacts. These showers produced a sufficient, albeit small sample of impact flashes with which to perform a luminous efficiency analysis similar to that outlined in Bellot Rubio et al. (2000) for the 1999 Leonids. An analysis of the Geminid, Lyrid, and Taurid lunar impacts is carried out herein in order to determine the luminous efficiency in the 400-800 nm wavelength range for each shower. Using the luminous efficiency, the kinetic energies and masses of these lunar impactors can be calculated.

Moser, D. E.↗
NASA NTRS2010

Combined Aircraft and Satellite-Derived Storm Electric Current and Lightning Rates Measurements and Implications for the Global Electric Circuit

Using rotating vane electric field mills and Gerdien capacitors, we measured the electric field profile and conductivity during 850 overflights of electrified shower clouds and thunderstorms spanning regions including the Southeastern United States, the Western Atlantic Ocean, the Gulf of Mexico, Central America and adjacent oceans, Central Brazil, and the South Pacific. The overflights include storms over land and ocean, with and without lightning, and with positive and negative fields above the storms. The measurements were made with the NASA ER-2 and the Altus-II high altitude aircrafts. Peak electric fields, with lightning transients removed, ranged from -1.0 kV/m to 16 kV/m, with a mean value of 0.9 kV/m. The median peak field was 0.29 kV/m. Integrating our electric field and conductivity data, we determined total conduction currents and flash rates for each overpass. With knowledge of the storm location (land or ocean) and type (with or without lightning), we determine the mean currents by location and type. The mean current for ocean storms with lightning is 1.6 A while the mean current for land storms with lightning is 1.0 A. The mean current for oceanic storms without lightning (i.e., electrified shower clouds) is 0.39 A and the mean current for land storms without lightning is 0.13 A. Thus, on average, land storms with or without lightning have about half the mean current as their corresponding oceanic storm counterparts. Over three-quarters (78%) of the land storms had detectable lightning, while less than half (43%) of the oceanic storms had lightning. We did not find any significant regional or latitudinal based patterns in our total conduction currents. By combining the aircraft derived storm currents and flash rates with diurnal lightning statistics derived from the Lightning Imaging Sensor (LIS) and Optical Transient Detector (OTD) low Earth orbiting satellites, we reproduce the diurnal variation in the global electric circuit (i.e., the Carnegie curve) to within 4% for all but two short periods of time. This excellent agreement with the Carnegie curve was obtained without any tuning or adjustment of the satellite or aircraft data. Given our data and assumptions, mean contributions to the global electric circuit are 0.7 kA (ocean) and 1.1 kA (land) from lightning-producing storms, and 0.22 kA (ocean) and 0.04 (land) from electrified shower clouds, resulting in a mean total conduction current estimate for the global electric circuit of 2.0 kA. Breaking the results down into mean storm counts reveals 1100 for land storms with lightning, 530 for ocean storms without lightning, 390 for ocean storms with lightning, and 330 for land storms without lightning.

Mach, Douglas M.↗
NASA NTRS2011

Luminous Efficiency of Hypervelocity Meteoroid Impacts on the Moon Derived from the 2006 Geminids, 2007 Lyrids, and 2008 Taurids

Since early 2006, NASA s Marshall Space Flight Center has been routinely monitoring the Moon for impact flashes produced by meteoroids striking the lunar surface. During this time, several meteor showers have produced multiple impact flashes on the Moon. The 2006 Geminids, 2007 Lyrids, and 2008 Taurids were observed with average rates of 5.5, 1.2, and 1.5 meteors/hr, respectively, for a total of 12 Geminid, 12 Lyrid, and 12 Taurid lunar impacts. These showers produced a sufficient, albeit small sample of impact flashes with which to perform a luminous efficiency analysis similar to that outlined in Bellot Rubio et al. (2000a, b) for the 1999 Leonids. An analysis of the Geminid, Lyrid, and Taurid lunar impacts is carried out herein in order to determine the luminous efficiency in the 400-800 nm wavelength range for each shower. Using the luminous efficiency, the kinetic energies and masses of these lunar impactors can be calculated from the observed flash intensity.

Moser, D. E.↗
NASA NTRS2007

Predicting the Blast of Lunar Soil Under a Rocket's Exhaust Jet

The blast of lunar soil represents a problem for the future missions planned for the moon. When the lander approached the ground during the Apollo missions, huge showers of dust particles were sent in all directions at extremely high velocities - including upwards towards the landing spacecraft. This represents a clear danger to the lander because the loss of visibility and the damage that can be produced to the vehicle itself. If there had been equipment on the ground, these showers of particles would have created a sand blasting effect over the equipment, possibly damaging optics and contaminating the equipment and depending on the size and velocity of the particles maybe even more extensive damage as the particles penetrated the outer surface of the equipment. Since the there is no air on the moon to slow down the particles, they can travel large distances at high speeds, in fact in some instances they can reach near escape velocity and go into an orbit around the moon and come all the way back to almost the same point where they were at the beginning; meaning that some of the lunar dust that came up during landing will shower back over the site. Once on the surface, the extremely fine dust had a habit of getting itself everywhere. During the Apollo missions it not only covered the astronauts' suits, but managed to work its way inside, damaging airtight joints and scratching up glass visors. The dust found its way inside the spacecraft, contaminating the floor and electronic systems inside, clogging air filters in the process. This is due to the fact that the lunar soil is extremely cohesive. The Lunar soil causes all of the same problems as sand does on Earth but unlike sand particles on Earth, which have smooth spherical shapes, the dust on the Moon is more like small particles of glass with sharper edges since there is no erosion on the lunar surface. During the Apollo missions the dust problem did not cause a big problem due to the fact of the length of duration of the missions. But as NASA plans to have long term missions to the moon the dust problem becomes an issue, due to multiple landings and the equipment that will be accumulated on the site. In order to mitigate these problems it is needed first to understand the physics of the problem in order to find the most suitable solution to protect equipment and vehicles during the next lunar missions..

Diaz, Carlos J. Sanchez↗
NASA NTRS2012

The Track Imaging Cerenkov Experiment

We describe a dedicated cosmic-ray telescope that explores a new method for detecting Cerenkov radiation from high-energy primary cosmic rays and the large particle air shower they induce upon entering the atmosphere. Using a camera comprising 16 multi-anode photomultiplier tubes for a total of 256 pixels, the Track Imaging Cerenkov Experiment (TrICE) resolves substructures in particle air showers with 0.086deg resolution. Cerenkov radiation is imaged using a novel two-part optical system in which a Fresnel lens provides a wide-field optical trigger and a mirror system collects delayed light with four times the magnification. TrICE records well-resolved cosmic-ray air showers at rates ranging between 0.01-0.1 Hz.

Wissel, S. A.↗
NASA NTRS2012

Practical Applications of Cosmic Ray Science: Spacecraft, Aircraft, Ground-Based Computation and Control Systems, and Human Health and Safety

Three twentieth century technological developments, 1) high altitude commercial and military aircraft; 2) manned and unmanned spacecraft; and 3) increasingly complex and sensitive solid state micro-electronics systems, have driven an ongoing evolution of basic cosmic ray science into a set of practical engineering tools needed to design, test, and verify the safety and reliability of modern complex technological systems. The effects of primary cosmic ray particles and secondary particle showers produced by nuclear reactions with the atmosphere, can determine the design and verification processes (as well as the total dollar cost) for manned and unmanned spacecraft avionics systems. Similar considerations apply to commercial and military aircraft operating at high latitudes and altitudes near the atmospheric Pfotzer maximum. Even ground based computational and controls systems can be negatively affected by secondary particle showers at the Earth s surface, especially if the net target area of the sensitive electronic system components is large. Finally, accumulation of both primary cosmic ray and secondary cosmic ray induced particle shower radiation dose is an important health and safety consideration for commercial or military air crews operating at high altitude/latitude and is also one of the most important factors presently limiting manned space flight operations beyond low-Earth orbit (LEO). In this paper we review the discovery of cosmic ray effects on the performance and reliability of microelectronic systems as well as human health and the development of the engineering and health science tools used to evaluate and mitigate cosmic ray effects in ground-based atmospheric flight, and space flight environments. Ground test methods applied to microelectronic components and systems are used in combinations with radiation transport and reaction codes to predict the performance of microelectronic systems in their operating environments. Similar radiation transport codes are used to evaluate possible human health effects of cosmic ray exposure, however, the health effects are based on worst-case analysis and extrapolation of a very limited human exposure data base combined with some limited experimental animal data. Finally, the limitations on human space operations beyond low-Earth orbit imposed by long term exposure to galactic cosmic rays are discussed.

Atwell, William↗
NASA NTRS2011

The Track Imaging Cerenkov Experiment

We describe a. dedicated cosmic-ray telescope that explores a new method for detecting Cerenkov radiation from high-energy primary cosmic rays and the large particle air shower they induce upon entering the atmosphere. Using a camera comprising 16 multi-anode photomultiplier tubes for a total of 256 pixels, the Track Imaging Cerenkov Experiment (TrICE) resolves substructures in particle air showers with 0,086 deg resolution. Cerenkov radiation is imaged using a novel two-part optical system in which a Fresnel lens provides a wide-field optical trigger and a mirror system collects delayed light with four times the magnification. TrICE records well-resolved cosmic-ray air showers at rates ranging between 0.01-0.1 Hz.

Wissel, S. A.↗
NASA NTRS2013

The NASA Fireball Network

In the summer of 2008, the NASA Meteoroid Environments Office (MEO) began to establish a video fireball network, based on the following objectives: (1) determine the speed distribution of cm size meteoroids, (2) determine the major sources of cm size meteoroids (showers/sporadic sources), (3) characterize meteor showers (numbers, magnitudes, trajectories, orbits), (4) determine the size at which showers dominate the meteor flux, (5) discriminate between re-entering space debris and meteors, and 6) locate meteorite falls. In order to achieve the above with the limited resources available to the MEO, it was necessary that the network function almost fully autonomously, with very little required from humans in the areas of upkeep or analysis. With this in mind, the camera design and, most importantly, the ASGARD meteor detection software were adopted from the University of Western Ontario's Southern Ontario Meteor Network (SOMN), as NASA has a cooperative agreement with Western's Meteor Physics Group. 15 cameras have been built, and the network now consists of 8 operational cameras, with at least 4 more slated for deployment in calendar year 2013. The goal is to have 15 systems, distributed in two or more groups east of automatic analysis; every morning, this server also automatically generates an email and a web page (http://fireballs.ndc.nasa.gov) containing an automated analysis of the previous night's events. This analysis provides the following for each meteor: UTC date and time, speed, start and end locations (longitude, latitude, altitude), radiant, shower identification, light curve (meteor absolute magnitude as a function of time), photometric mass, orbital elements, and Tisserand parameter. Radiant/orbital plots and various histograms (number versus speed, time, etc) are also produced. After more than four years of operation, over 5,000 multi-station fireballs have been observed, 3 of which potentially dropped meteorites. A database containing data on all these events, including the videos and calibration information, has been developed and is being modified to include data from the SOMN and other camera networks.

Cooke, William J.↗
NASA NTRS2012

Practical Applications of Cosmic Ray Science: Spacecraft, Aircraft, Ground Based Computation and Control Systems and Human Health and Safety

In this paper we review the discovery of cosmic ray effects on the performance and reliability of microelectronic systems as well as on human health and safety, as well as the development of the engineering and health science tools used to evaluate and mitigate cosmic ray effects in earth surface, atmospheric flight, and space flight environments. Three twentieth century technological developments, 1) high altitude commercial and military aircraft; 2) manned and unmanned spacecraft; and 3) increasingly complex and sensitive solid state micro-electronics systems, have driven an ongoing evolution of basic cosmic ray science into a set of practical engineering tools (e.g. ground based test methods as well as high energy particle transport and reaction codes) needed to design, test, and verify the safety and reliability of modern complex electronic systems as well as effects on human health and safety. The effects of primary cosmic ray particles, and secondary particle showers produced by nuclear reactions with spacecraft materials, can determine the design and verification processes (as well as the total dollar cost) for manned and unmanned spacecraft avionics systems. Similar considerations apply to commercial and military aircraft operating at high latitudes and altitudes near the atmospheric Pfotzer maximum. Even ground based computational and controls systems can be negatively affected by secondary particle showers at the Earth's surface, especially if the net target area of the sensitive electronic system components is large. Accumulation of both primary cosmic ray and secondary cosmic ray induced particle shower radiation dose is an important health and safety consideration for commercial or military air crews operating at high altitude/latitude and is also one of the most important factors presently limiting manned space flight operations beyond low-Earth orbit (LEO).

Atwell, William↗
NASA NTRS2015

Practical Applications of Cosmic Ray Science: Spacecraft, Aircraft, Ground-Based Computation and Control Systems, Exploration, and Human Health and Safety

In this presentation a review of galactic cosmic ray (GCR) effects on microelectronic systems and human health and safety is given. The methods used to evaluate and mitigate unwanted cosmic ray effects in ground-based, atmospheric flight, and space flight environments are also reviewed. However not all GCR effects are undesirable. We will also briefly review how observation and analysis of GCR interactions with planetary atmospheres and surfaces and reveal important compositional and geophysical data on earth and elsewhere. About 1000 GCR particles enter every square meter of Earth’s upper atmosphere every second, roughly the same number striking every square meter of the International Space Station (ISS) and every other low- Earth orbit spacecraft. GCR particles are high energy ionized atomic nuclei (90% protons, 9% alpha particles, 1% heavier nuclei) traveling very close to the speed of light. The GCR particle flux is even higher in interplanetary space because the geomagnetic field provides some limited magnetic shielding. Collisions of GCR particles with atomic nuclei in planetary atmospheres and/or regolith as well as spacecraft materials produce nuclear reactions and energetic/highly penetrating secondary particle showers. Three twentieth century technology developments have driven an ongoing evolution of basic cosmic ray science into a set of practical engineering tools needed to design, test, and verify the safety and reliability of modern complex technological systems and assess effects on human health and safety effects. The key technology developments are: 1) high altitude commercial and military aircraft; 2) manned and unmanned spacecraft; and 3) increasingly complex and sensitive solid state micro-electronics systems. Space and geophysical exploration needs drove the development of the instruments and analytical tools needed to recover compositional and structural data from GCR induced nuclear reactions and secondary particle showers. Finally, the possible role of GCR secondary particle showers in addressing an important homeland security problem, finding nuclear contraband and weapons, will be briefly reviewed.

Koontz, Steve↗
NASA NTRS2015

The 2016 Perseids

The Perseid meteor shower has been observed since ancient times. One of the most prolific annual showers, the Perseids have also been known to outburst. At least two spacecraft have suffered anomalies potentially caused by meteoroid impacts during Perseid outbursts. Olympus, an ESA telecommunications satellite, was likely impacted by a Perseid meteoroid during the 1993 outburst that ultimately led to the termination of the spacecraft's mission. Landsat-5, an imaging satellite jointly managed by NASA and the USGS, lost gyro stability during the peak of the Perseids in 2009. The Perseid meteor shower is expected to outburst again in 2016. Stream model predictions place the peak activity on the night of August 11-12 (UT) as the Earth passes through several old debris trails from parent comet 109P/Swift-Tuttle. Observing geometry favors Europe at the onset, but increased activity for about half a day means that North America is also well-placed for observations. A call for observations to characterize the stream and constrain numerical models is made. Modeling results, observing geometry, and spacecraft risk during the 2016 Perseids will be discussed.

Moser, D. E.↗
NASA NTRS2015

Optical Meteor Systems Used by the NASA Meteoroid Environment Office

The NASA Meteoroid Environment Office (MEO) uses two main meteor camera networks to characterize the meteoroid environment: an all sky system and a wide field system to study cm and mm size meteors respectively. The NASA All Sky Fireball Network consists of fifteen meteor video cameras in the United States, with plans to expand to eighteen cameras by the end of 2015. The camera design and All-Sky Guided and Real-time Detection (ASGARD) meteor detection software [1, 2] were adopted from the University of Western Ontario's Southern Ontario Meteor Network (SOMN). After seven years of operation, the network has detected over 12,000 multi-station meteors, including meteors from at least 53 different meteor showers. The network is used for speed distribution determination, characterization of meteor showers and sporadic sources, and for informing the public on bright meteor events. The NASA Wide Field Meteor Network was established in December of 2012 with two cameras and expanded to eight cameras in December of 2014. The two camera configuration saw 5470 meteors over two years of operation with two cameras, and has detected 3423 meteors in the first five months of operation (Dec 12, 2014 - May 12, 2015) with eight cameras. We expect to see over 10,000 meteors per year with the expanded system. The cameras have a 20 degree field of view and an approximate limiting meteor magnitude of +5. The network's primary goal is determining the nightly shower and sporadic meteor fluxes. Both camera networks function almost fully autonomously with little human interaction required for upkeep and analysis. The cameras send their data to a central server for storage and automatic analysis. Every morning the servers automatically generates an e-mail and web page containing an analysis of the previous night's events. The current status of the networks will be described, alongside with preliminary results. In addition, future projects, CCD photometry and broadband meteor color camera system, will be discussed.

Kingery, A. M.↗
NASA NTRS2020

Exploring a Potentially Significant New(?) Mechanism for Methane Generation on Mars

An unexplored mechanism for methane production on Mars is presented here. Meteor showers have been hypothesized [1] as an explanation for episodic martian methane events [2-7], as the timing of meteor showers consistently correlates with the episodic methane events. The hypothesis [1] relied on production of methane via UV photolysis of extraterrestrial carbonaceous material [8,9] following dissemination of material into the martian atmosphere and onto the surface. Recently, new insights have emerged about an overlooked mechanism for methane production – plasma methanation [10,11] of martian atmospheric CO2 in meteor plasma. This mechanism can generate methane in addition to that produced by the previously explored methods of direct thermal evolution and UV photolysis, adding to the total methane budget produced through meteor infall. It also delivers methane in a rapid manner consistent with past observations of episodic methane “plumes” on Mars, and at altitudes where methane is rapidly removed afterwards. Methane produced by plasma methanation occurs at high altitude, which matches observations made on Mars where measurements collected through the full thickness of the martian atmosphere are of consistently higher methane concentrations (>10 ppbv [2-6]) than those recorded on the surface by the Mars Science Laboratory (MSL) rover (<10 ppbv [7]). High-altitude methane should be detected by the ESA Trace Gas Orbiter (TGO) which has not noted any methane to date. This result is puzzling regardless of the source of methane, but may be explained by the random nature of meteor shower outbursts – a significant infall may simply not have occurred (yet) during the ~3-Earth-year period of TGO observations.

Fries, M.↗
NASA NTRSDate not supplied

Timed Collections in the NASA Cosmic Dust Aircraft Collected Particle Collection Including Previous Collectors

The NASA Cosmic Dust Collections includes a collection of interplanetary particles gathered using high-altitude aircraft (the Aircraft Collected Particle collection, or ACP). These particles include cosmic-origin particles as well as particles of terrestrial origin such as volcanic ash, solid rocket motor effluent, and terrestrial dust. The cosmic-origin dust comes from two principal sources - material originating from the diffuse interplanetary background which are uncoupled from the orbits of larger bodies, and cometary-origin particles which are dynamically coupled with the orbits of their parent bodies to form dust streams. These dust stream particles generate short-lived, annual meteor showers and are important because, if they can be identified as originating from a given dust stream, they can be studied in the laboratory as samples of a specific comet. Collecting these particles requires dedicated ACP flights which are timed to coincide with a specific meteor shower. These “timed collections” hold the promise of providing samples from a suite of comets including those never visited by spacecraft [1-3]. This abstract describes a recent (Dec 2020) timed collection attempt, lists previous timed collections with collected particles available for request from the NASA Cosmic Dust Collections, as well as listing ACP collectors which were collected when no meteor showers were active for potential use as control samples.

cosmic dust↗
NASA NTRS1973

Comet Encke: Meteor metallic ion identification by mass spectrometer

Positive metallic ions have been measured in the earth's atmosphere between 85 and 120 km, during the period of the beta Taurids meteor shower, which is associated with Comet Encke. The ions originate during and following ablation of extraterrestrial debris by the earth's atmosphere. The enhancement of metal ion density during meteor showers is primary evidence for their extraterrestrial origin. The present results were obtained from a rocket-borne ion mass spectrometer.

Goldberg, R. A.↗
NASA NTRS1974

International Cosmic Ray Conference, 13th, University of Denver, Denver, Colo., August 17-30, 1973, Proceedings. Volumes 3 & 4

Volumes 3 and 4 contain papers dealing with measurements of muons and neutrinos, ultrahigh-energy interactions, extensive air showers, and details of experimental techniques and instrumentation. Attention is given to the zenith angle and underground depth dependence of cosmic ray muons, muon charge ratios and energy spectra, extraterrestrial sources of neutrinos, strong interaction data from new accelerators, searches for quarks and other new particles, hadron fluxes and propagation in the atmosphere, high-energy gamma-ray measurements, and new models and theories for high-energy strong interactions. Extensive air showers are examined in papers dealing with associated Cerenkov light, radio emission, structure, the hadron content, and primaries. The design, operation, and performance of various detectors are explained. Individual items are announced in this issue.

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