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Moser, Danielle

Publications and source records attributed to Moser, Danielle.

29 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS2014

The 2014 May Camelopardalid Meteor Shower

On May 24, 2014 Earth will encounter multiple streams of debris laid down by Comet 209P LINEAR. This will likely produce a new meteor shower, never before seen. Rates predicted to be from 100 to 1000 meteors per hour between 2 and 4 AM EDT, so we are dealing with a meteor outburst, potentially a storm. Peak rate of ~200 per hour best current estimate. Difficult to calibrate models due to lack of past observations. Models indicate mm size particles in stream, so potential risk to Earth orbiting spacecraft.

Cooke, Bill↗
NASA NTRS2013

Large Meteoroid Impact on the Moon 17 March 2013

NASA's routine monitoring of lunar impact flashes has recorded nearly 300 impacts since 2006. On 17 March 2013 the brightest event to date was observed in two 0.35m telescopes at the Marshall Space Flight Center. With a peak red magnitude brighter than 4.3 and an impact flash visible for over 1 second, the impact kinetic energy was equivalent to nearly 5 tons of TNT. A possible association with a meteor shower observed in the Earth's atmosphere will be described. Corresponding crater dimensions and observability of the impact crater by Lunar Reconnaissance Orbiter will also be discussed.

Suggs, Robert M.↗
NASA NTRS2013

Large Meteoroid Impact on the Moon 17 March 2013

NASA's routine monitoring of lunar impact flashes has recorded nearly 300 impacts since 2006. On 17 March 2013 the brightest event to date was observed in two 0.35m telescopes at the Marshall Space Flight Center. With a peak red magnitude brighter than 4.3 and an impact flash visible for over 1 second, the impact kinetic energy was equivalent to nearly 5 tons of TNT. A possible association with a meteor shower observed in the Earth's atmosphere will be described. Corresponding crater dimensions and observability of the impact crater by Lunar Reconnaissance Orbiter will also be discussed.

Suggs, Robert M.↗
NASA NTRS2011

Lunar Impact Detections During the 2010 Geminid Meteor Shower

Lunar video observations are routinely conducted at the NASA Marshall Space Flight Center in Huntsville Alabama for the detection of meteoroid impacts. Over 240 impacts have been detected since the start of the observing program initiated approximately 5 years ago. During this time it has been fairly rare that lunar observing conditions and the weather have been favorable during the peak of the major showers. However, observing conditions were marginally favorable during the peak of the 2010 Geminids. On Dec. 14, 2010 approximately 5.5 hours of video were recorded. Even though the lunar phase was just outside the constraints established for optimum lunar impact monitoring, the resulting video was of sufficient quality that 21 lunar impacts were detected yielding an average impact rate of approximately 4 per hour. This compares to 17 lunar impacts detected over 40 nights of observations ( approximately 100 hours of lunar video) yielding an average impact rate of 1 per 6 hours for the whole of 2010, excluding Dec. 14. The results of the 2010 Geminid lunar impact detections will be discussed along with previous results from the 2006 Geminid shower that also coincided within the lunar observing window.

Suggs, Ron↗
NASA NTRS2010

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

This slide presentation reviews NASA's program that observes and investigates the impact of meteoroids on the mooon. The meteor showers dominate the environment in the 100g to kilograms range. With a sufficient number of observed impacts the technique outlined can help determine the population index for some of the meteoroid showers.

Suggs, Rob↗
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 NTRS2008

Flux of Kilogram-Sized Meteoroids from Lunar Impact Monitoring

Routine lunar impact monitoring has harvested over 110 impacts in 2 years of observations using 0.25, 0.36 and 0.5 m telescopes and low-light-level video cameras. The night side of the lunar surface provides a large collecting area for detecting these impacts and allows estimation of the flux of meteoroids down to a limiting luminous energy. In order to determine the limiting mass for these observations, models of the sporadic meteoroid environment were used to determine the velocity distribution and new measurements of luminous efficiency were made at the Ames Vertical Gun Range. The flux of meteoroids in this size range has implications for Near Earth Object populations as well as for estimating impact ejecta risk for future lunar missions.

Suggs, Robert↗
NASA NTRS2008

Flux of Kilogram-sized Meteoroids from Lunar Impact Monitoring. Supplemental Movies

These videos, and audio accompany the slide presentation "Flux of Kilogram-sized Meteoroids from Lunar Impact Monitoring." The slide presentation reviews the routine lunar impact monitoring that has harvested over 110 impacts in 2 years of observations using telescopes and low-light level video cameras. The night side of the lunar surface provides a large collecting area for detecting these impacts and allows estimation of the flux of meteoroids down to a limiting luminous energy.

Suggs, Robert↗
NASA NTRS2007

Measurement of Primary Ejecta From Normal Incident Hypervelocity Impact on Lunar Regolith Simulant

The National Aeronautics and Space Administration (NASA) continues to make progress toward long-term lunar habitation. Critical to the design of a lunar habitat is an understanding of the lunar surface environment. A subject for further definition is the lunar primary ejecta environment. The document NASA SP-8013 was developed for the Apollo program and is the latest definition of the primary ejecta environment. There is concern that NASA SP-8013 may over-estimate the lunar primary ejecta environment. NASA's Meteoroid Environment Office (MEO) has initiated several tasks to improve the accuracy of our understanding of the lunar surface primary ejecta environment. This paper reports the results of experiments on projectile impact into pumice targets, simulating lunar regolith. The Ames Vertical Gun Range (AVGR) was used to accelerate spherical Pyrex projectiles of 0.29g to velocities ranging between 2.5 km/s and 5.18 km/s. Impact on the pumice target occurred at normal incidence. The ejected particles were detected by thin aluminum foil targets placed around the pumice target in a 0.5 Torr vacuum. A simplistic technique to characterize the ejected particles was formulated. Improvements to this technique will be discussed for implementation in future tests.

Edwards, David L.↗
NASA NTRS2004

Meteor Outbursts and Storms from the Spacecraft Hazard Perspective

The recent Leonid meteor storms have propelled meteor shower forecasting from an idea into the realm of practical application, invoked several times per year by numerous spacecraft. This paper will describe shower activity predictions, which give zenith hourly rate (ZHR) as a function of time, and how these are translated into spacecraft risks. Common spacecraft meteor shower mitigation strategies will also be discussed, and the important issue as to when to implement such operations considered. It should be noted that, while the recent meteor storms did not result in the loss of a vehicle, there were a few spacecraft anomalies attributed to Leonid strikes, and the nature of these will be commented upon. Finally, we assess the current state of the art in shower forecasting, and take a look "down the road" at some possible outbursts in the near future.

Cooke, William↗