Nebil Misconi - Academia.edu (original) (raw)

Papers by Nebil Misconi

Research paper thumbnail of Ground-Based Observations of Near Ecliptic Zodiacal Light Brightness

Springer eBooks, 1985

Ground-based observations of the evening zodiacal light taken by Weinberg and Mann from Mt. Halea... more Ground-based observations of the evening zodiacal light taken by Weinberg and Mann from Mt. Haleakala, Hawaii, during March 1966 are used to derive a table of zodiacal light brightnesses at high spatial resolution (as little as 0.5° in differential ecliptic longitude X-X and 1.0° in ecliptic latitude 0) over the region 29. 5°< X-X < 56° ,-30°<6<30°. Significant differences are found in the brightness distributions above and below the ecliptic plane. Brightness, polarization, color and angular dependence of the light of the night sky were systematically observed by Weinberg and Mann from Mt. Haleakala, Hawaii between 1965 and 1969 (Weinberg and Mann, 1967). One of the several observing techniques that was used involved scanning the main cone of the zodiacal light over a range of 160° in azimuth centered on the ecliptic, beginning (evening) or ending (morning) with the onset of astronomical twilight. A multicolor photopolarimeter scanned back and forth in azimuth at 2.5 deg/sec, incrementing elevation in 1° steps between 5° and 24°. A sample of these data, taken in March 1966 at 5080A\ is reduced to isolate the zodiacal light. Additional data and full details of the observations, calibration, and data reduction will be presented elsewhere. Data below elevation 10° are omitted here due to difficulties in the atmospheric corrections. The measured brightnesses were converted to absolute units (Si0(V) r ") b y r e f e r e n c e t o a calibrated (by NBS Fritz Peak Observatory), 17.8-cm diameter ^C-activated phosphor source. The source was placed over the objective before and after each night's observations, filling both the aperture and the 3° diameter field of view (FOV). Bright stars were used to obtain an independent absolute calibration, the two methods agreeing to better than 5 percent. Extinction corrections were made with coefficients derived from observations of bright stars using the same instrument. Atmospheric scattering corrections followed the method outlined by Weinberg (1964). The brightness contributed by "resolved" stars in each FOV were subtracted using a special merged star catalog developed for each color used with this instrument. Background starlight was subtracted using data obtained from Pioneer 10 observations beyond the asteroid belt, where the zodi

Research paper thumbnail of Preliminary Results on the Photometric Axis of the Zodiacal Light from Ground-based Observations

Bulletin of the American Astronomical Society, Mar 1, 1977

Research paper thumbnail of Possible Effects of Mars on the Symmetry Plane of Interplanetary Dust

Bulletin of the American Astronomical Society, 1977

Research paper thumbnail of The Interaction of Small Particles with Laser Beams

0~-INdsri t 7. ' ;td 4. PERFORMING ORGANIZATION m " NUMBER(S) 5 MONITORING ORGANIZATION REPORT NU... more 0~-INdsri t 7. ' ;td 4. PERFORMING ORGANIZATION m " NUMBER(S) 5 MONITORING ORGANIZATION REPORT NUMBER(S) ' ,=~I DD FORM 1473.84 MAR 83 APR edition may be used until exhausted SECURITY CLASSIFICATION O THIS PAGE All other editions are obsolete 4,-, 6-., .. , o; %% %.' ?. ' <t * .-% % "4z'r erPp.?'

Research paper thumbnail of Detecting the light of the night sky in Mars

Natural Science, 2011

In this paper a new methodology is outlined to detect the dust content in the Martian atmosphere ... more In this paper a new methodology is outlined to detect the dust content in the Martian atmosphere during nighttime. In the previous Lander missions to Mars, scientists were able to determine the dust load in the Martian atmosphere during daylight using spectral lines of the Sun. Since the dynamics of Martian dust storms had been determined to be very rapid changing over times of hours and not days, it is imperative to determine the dust load during nighttime, so future astronauts to Mars can take protective measures for their equipment. They can also factor this effect for their planned activities during daytime. The new methodology greatly improves the classical method for determining the extinction in the Earth's atmosphere. The classical method uses observations of bright stars from which the optical depth,  total , can then be deduced from the classical brightness equation. The classical method succeeds reasonably well at high elevation angles from the horizon but fails dramatically at low elevation angles. It also determines  total from the slope of a plot of observed brightness of a bright star vs. air mass at all elevations. The plot shows a straight line at high elevations angles, which then curves and becomes uncertain at low elevation angles. The new methodology bypasses this severe difficulty by simply eliminating this plot, and by acquiring the brightness of a bright star above the atmosphere (no extinction) and compares it to the observed brightness of the same star below the atmosphere at all elevations.

Research paper thumbnail of N O T I C e This Document Has Been Reproduced from Microfiche. Although It is Recognized That Certain Portions Are Illegible, It is Being Released in the Interest of Making Available as Much

The report describRs the development of a tilotelemetry system that ig hermetically sealed within... more The report describRs the development of a tilotelemetry system that ig hermetically sealed within a total hip replacement implant. This task was performed through a cooperative effort between JPL and the Biomechanics Section of the Division of Orthopedic Surgery at UCLA. The telemetry system transmits six channels of stress data in order to reconstruct the major forces acti^ig on the neck of the prosthesis and uses an induction power coupling technique to eliminate the need for internal batteries. The report discus qes the activities associated with the telemetry microminiaturization, data recovery console, hardware fabrications, power inductiori systems, electrical and mechanical testing and hermetic sealing test results.

Research paper thumbnail of Brightness contribution of zodiacal dust along the line of sight in and pout of the elliptic plane and in the F-corona

Planetary and Space Science, 1987

Research paper thumbnail of Interplanetary dust dynamics. II - Poynting-Robertson drag and planetary perturbations on cometary dust. III - Dust released from P/Enke - Distribution with respect to the zodiacal cloud

Icarus, 1987

Whereas the inner planets' perturbations on meteoroids' and larger interplanetary bodies' orbits ... more Whereas the inner planets' perturbations on meteoroids' and larger interplanetary bodies' orbits have been studied extensively, they are usually neglected in studies of the dynamics of smaller particles producing the zodiacal light through scattering of sunlight. Forces acting on these dust particles are fairly well known and include radiation forces and interaction with the solar wind. This article is the first in a series aimed at improving our knowledge of the dynamical evolution of dust in interplanetary space by studying the combined effects of these perturbations including gravitational perturbations by the planets Venus, Earth, Mars, and Jupiter. The necessity of including effects of the inner planets in dust dynamics investigations is established. Sample trajectories are presented to illustrate commonly occurring phenomenae, such as nonmonotonic changes in semimajor axis, eccentricity, inclination, and in the line of nodes. These perturbations are shown to be due to the inner planets as opposted to Jupiter or nongravitational forces. ,o 1986 Academic Press, Inc.

Research paper thumbnail of The Inner Zodiacal Light: What is the Brightness Distribution along the Line of Sight?

Bulletin of the American Astronomical Society, Jun 1, 1974

Research paper thumbnail of Radiation-induced rotation of small celestial bodies

Final Report Florida Inst of Tech Melbourne Dept of Mechanical and Aerospace Engineering, Mar 1, 1992

The rotation was studied of particles in a simulated space environment via a technique known as L... more The rotation was studied of particles in a simulated space environment via a technique known as Laser Particle Levitation. The combination of both a high vacuum and optical laser levitation to negate the effects of Earth's gravity, simulate the space environment. The rotation mechanism under study is known as the 'Windmill Effect,' which is a spin mechanism that suggests that the interaction of the photon field from a star with the surface irregularities of cosmic dust will cause them to spin due to the imbalance in the directionality of the scattered photons which necessitates a non-zero angular momentum. This conclusion is based on the random nature of the orientation of the sites of surface irregularities. The general object is to study the behavior of particles in orbits around the Earth, both natural and man made, as well as interplanetary and circumstellar particles. To meet this objective, an apparatus was constructed which was designed to allow optical levitation in a vacuum.

Research paper thumbnail of On the photometric axis of the zodiacal light

Astronomy and Astrophysics, Nov 1, 1977

Research paper thumbnail of The interaction of solid particles with laser beams

Light scattering curves of intensity vs. scattering angle were made of layers of transparent sili... more Light scattering curves of intensity vs. scattering angle were made of layers of transparent silica particles, single silica particles isolated by optical levitation; using an Argon ion laser light source and a goniometer mounted silicon photodiode detector. Scattering measurements of spherical particles demonstrated an excellent agreement with Mie theory. Spheroids and irregular particles were also measured. Dynamics of particles in

Research paper thumbnail of Coronal Mass Ejections, Ion Drag and Rotational Bursting of the Dust

Research paper thumbnail of The Position of the Symmetry Plane of Interplanetary Dust in the Gegenschein

Research paper thumbnail of Solar Flare Effects on the Zodiacal Light?

Astronomy and Astrophysics, Oct 1, 1976

Research paper thumbnail of The radiation-induced rotation of cosmic dust particles: A feasibility study

Research paper thumbnail of Studies of a laser/nuclear thermal-hardened body armor. Final report, 31 Jan 91-30 Sep 91

The problem of laser/nuclear hardening of body armors and other applications, such as rigid wall,... more The problem of laser/nuclear hardening of body armors and other applications, such as rigid wall, etc, has been investigated in this study. Earlier results from studies of hardening against space systems, which were supported by the Air Force Office of Scientific Research (AFOSR) and carried out by the Principal Investigator during 1984 to 1989 are summarized. The concepts of particle

Research paper thumbnail of Can cometary dust perturbed by the inner planets be an explanation for the observed distribution of interplanetary dust?

Research paper thumbnail of Journey From a Comet Parent Body to 1 AU, Orbital Evolution of Dust Particles

Research paper thumbnail of Quasi-analytical solutions for APSIDAL motion in the three-body problem: Sun—minor planet—Jupiter

Earth, Planets and Space, 1999

Research paper thumbnail of Ground-Based Observations of Near Ecliptic Zodiacal Light Brightness

Springer eBooks, 1985

Ground-based observations of the evening zodiacal light taken by Weinberg and Mann from Mt. Halea... more Ground-based observations of the evening zodiacal light taken by Weinberg and Mann from Mt. Haleakala, Hawaii, during March 1966 are used to derive a table of zodiacal light brightnesses at high spatial resolution (as little as 0.5° in differential ecliptic longitude X-X and 1.0° in ecliptic latitude 0) over the region 29. 5°< X-X < 56° ,-30°<6<30°. Significant differences are found in the brightness distributions above and below the ecliptic plane. Brightness, polarization, color and angular dependence of the light of the night sky were systematically observed by Weinberg and Mann from Mt. Haleakala, Hawaii between 1965 and 1969 (Weinberg and Mann, 1967). One of the several observing techniques that was used involved scanning the main cone of the zodiacal light over a range of 160° in azimuth centered on the ecliptic, beginning (evening) or ending (morning) with the onset of astronomical twilight. A multicolor photopolarimeter scanned back and forth in azimuth at 2.5 deg/sec, incrementing elevation in 1° steps between 5° and 24°. A sample of these data, taken in March 1966 at 5080A\ is reduced to isolate the zodiacal light. Additional data and full details of the observations, calibration, and data reduction will be presented elsewhere. Data below elevation 10° are omitted here due to difficulties in the atmospheric corrections. The measured brightnesses were converted to absolute units (Si0(V) r ") b y r e f e r e n c e t o a calibrated (by NBS Fritz Peak Observatory), 17.8-cm diameter ^C-activated phosphor source. The source was placed over the objective before and after each night's observations, filling both the aperture and the 3° diameter field of view (FOV). Bright stars were used to obtain an independent absolute calibration, the two methods agreeing to better than 5 percent. Extinction corrections were made with coefficients derived from observations of bright stars using the same instrument. Atmospheric scattering corrections followed the method outlined by Weinberg (1964). The brightness contributed by "resolved" stars in each FOV were subtracted using a special merged star catalog developed for each color used with this instrument. Background starlight was subtracted using data obtained from Pioneer 10 observations beyond the asteroid belt, where the zodi

Research paper thumbnail of Preliminary Results on the Photometric Axis of the Zodiacal Light from Ground-based Observations

Bulletin of the American Astronomical Society, Mar 1, 1977

Research paper thumbnail of Possible Effects of Mars on the Symmetry Plane of Interplanetary Dust

Bulletin of the American Astronomical Society, 1977

Research paper thumbnail of The Interaction of Small Particles with Laser Beams

0~-INdsri t 7. ' ;td 4. PERFORMING ORGANIZATION m " NUMBER(S) 5 MONITORING ORGANIZATION REPORT NU... more 0~-INdsri t 7. ' ;td 4. PERFORMING ORGANIZATION m " NUMBER(S) 5 MONITORING ORGANIZATION REPORT NUMBER(S) ' ,=~I DD FORM 1473.84 MAR 83 APR edition may be used until exhausted SECURITY CLASSIFICATION O THIS PAGE All other editions are obsolete 4,-, 6-., .. , o; %% %.' ?. ' <t * .-% % "4z'r erPp.?'

Research paper thumbnail of Detecting the light of the night sky in Mars

Natural Science, 2011

In this paper a new methodology is outlined to detect the dust content in the Martian atmosphere ... more In this paper a new methodology is outlined to detect the dust content in the Martian atmosphere during nighttime. In the previous Lander missions to Mars, scientists were able to determine the dust load in the Martian atmosphere during daylight using spectral lines of the Sun. Since the dynamics of Martian dust storms had been determined to be very rapid changing over times of hours and not days, it is imperative to determine the dust load during nighttime, so future astronauts to Mars can take protective measures for their equipment. They can also factor this effect for their planned activities during daytime. The new methodology greatly improves the classical method for determining the extinction in the Earth's atmosphere. The classical method uses observations of bright stars from which the optical depth,  total , can then be deduced from the classical brightness equation. The classical method succeeds reasonably well at high elevation angles from the horizon but fails dramatically at low elevation angles. It also determines  total from the slope of a plot of observed brightness of a bright star vs. air mass at all elevations. The plot shows a straight line at high elevations angles, which then curves and becomes uncertain at low elevation angles. The new methodology bypasses this severe difficulty by simply eliminating this plot, and by acquiring the brightness of a bright star above the atmosphere (no extinction) and compares it to the observed brightness of the same star below the atmosphere at all elevations.

Research paper thumbnail of N O T I C e This Document Has Been Reproduced from Microfiche. Although It is Recognized That Certain Portions Are Illegible, It is Being Released in the Interest of Making Available as Much

The report describRs the development of a tilotelemetry system that ig hermetically sealed within... more The report describRs the development of a tilotelemetry system that ig hermetically sealed within a total hip replacement implant. This task was performed through a cooperative effort between JPL and the Biomechanics Section of the Division of Orthopedic Surgery at UCLA. The telemetry system transmits six channels of stress data in order to reconstruct the major forces acti^ig on the neck of the prosthesis and uses an induction power coupling technique to eliminate the need for internal batteries. The report discus qes the activities associated with the telemetry microminiaturization, data recovery console, hardware fabrications, power inductiori systems, electrical and mechanical testing and hermetic sealing test results.

Research paper thumbnail of Brightness contribution of zodiacal dust along the line of sight in and pout of the elliptic plane and in the F-corona

Planetary and Space Science, 1987

Research paper thumbnail of Interplanetary dust dynamics. II - Poynting-Robertson drag and planetary perturbations on cometary dust. III - Dust released from P/Enke - Distribution with respect to the zodiacal cloud

Icarus, 1987

Whereas the inner planets' perturbations on meteoroids' and larger interplanetary bodies' orbits ... more Whereas the inner planets' perturbations on meteoroids' and larger interplanetary bodies' orbits have been studied extensively, they are usually neglected in studies of the dynamics of smaller particles producing the zodiacal light through scattering of sunlight. Forces acting on these dust particles are fairly well known and include radiation forces and interaction with the solar wind. This article is the first in a series aimed at improving our knowledge of the dynamical evolution of dust in interplanetary space by studying the combined effects of these perturbations including gravitational perturbations by the planets Venus, Earth, Mars, and Jupiter. The necessity of including effects of the inner planets in dust dynamics investigations is established. Sample trajectories are presented to illustrate commonly occurring phenomenae, such as nonmonotonic changes in semimajor axis, eccentricity, inclination, and in the line of nodes. These perturbations are shown to be due to the inner planets as opposted to Jupiter or nongravitational forces. ,o 1986 Academic Press, Inc.

Research paper thumbnail of The Inner Zodiacal Light: What is the Brightness Distribution along the Line of Sight?

Bulletin of the American Astronomical Society, Jun 1, 1974

Research paper thumbnail of Radiation-induced rotation of small celestial bodies

Final Report Florida Inst of Tech Melbourne Dept of Mechanical and Aerospace Engineering, Mar 1, 1992

The rotation was studied of particles in a simulated space environment via a technique known as L... more The rotation was studied of particles in a simulated space environment via a technique known as Laser Particle Levitation. The combination of both a high vacuum and optical laser levitation to negate the effects of Earth's gravity, simulate the space environment. The rotation mechanism under study is known as the 'Windmill Effect,' which is a spin mechanism that suggests that the interaction of the photon field from a star with the surface irregularities of cosmic dust will cause them to spin due to the imbalance in the directionality of the scattered photons which necessitates a non-zero angular momentum. This conclusion is based on the random nature of the orientation of the sites of surface irregularities. The general object is to study the behavior of particles in orbits around the Earth, both natural and man made, as well as interplanetary and circumstellar particles. To meet this objective, an apparatus was constructed which was designed to allow optical levitation in a vacuum.

Research paper thumbnail of On the photometric axis of the zodiacal light

Astronomy and Astrophysics, Nov 1, 1977

Research paper thumbnail of The interaction of solid particles with laser beams

Light scattering curves of intensity vs. scattering angle were made of layers of transparent sili... more Light scattering curves of intensity vs. scattering angle were made of layers of transparent silica particles, single silica particles isolated by optical levitation; using an Argon ion laser light source and a goniometer mounted silicon photodiode detector. Scattering measurements of spherical particles demonstrated an excellent agreement with Mie theory. Spheroids and irregular particles were also measured. Dynamics of particles in

Research paper thumbnail of Coronal Mass Ejections, Ion Drag and Rotational Bursting of the Dust

Research paper thumbnail of The Position of the Symmetry Plane of Interplanetary Dust in the Gegenschein

Research paper thumbnail of Solar Flare Effects on the Zodiacal Light?

Astronomy and Astrophysics, Oct 1, 1976

Research paper thumbnail of The radiation-induced rotation of cosmic dust particles: A feasibility study

Research paper thumbnail of Studies of a laser/nuclear thermal-hardened body armor. Final report, 31 Jan 91-30 Sep 91

The problem of laser/nuclear hardening of body armors and other applications, such as rigid wall,... more The problem of laser/nuclear hardening of body armors and other applications, such as rigid wall, etc, has been investigated in this study. Earlier results from studies of hardening against space systems, which were supported by the Air Force Office of Scientific Research (AFOSR) and carried out by the Principal Investigator during 1984 to 1989 are summarized. The concepts of particle

Research paper thumbnail of Can cometary dust perturbed by the inner planets be an explanation for the observed distribution of interplanetary dust?

Research paper thumbnail of Journey From a Comet Parent Body to 1 AU, Orbital Evolution of Dust Particles

Research paper thumbnail of Quasi-analytical solutions for APSIDAL motion in the three-body problem: Sun—minor planet—Jupiter

Earth, Planets and Space, 1999

Research paper thumbnail of Laser & Particle Beams Paper-1.docx

Abstract. A new technique for levitating solid particles inside a vacuum chamber is developed us... more Abstract. A new technique for levitating solid particles inside a vacuum chamber is developed using a proton beam. This new technique differs from the classical laser-levitation technique invented by Ashkin in that it does not heat up light-absorbing levitated particles to vaporization. This unique property of the method will make it possible to levitate real interplanetary dust particles in a vacuum chamber and study their spin-up dynamics in a ground-based laboratory. It is found that a flux of protons from a proton gun of ~ 1015 cm-2 sec-1 is needed to levitate a 10 mm particle. Confinement of the levitated particle can be achieved by a Z or θ pinch to create a gravity well, or by making the beam profile doughnut in shape. In levitating real interplanetary particles, two spinup mechanisms can be investigated using this technique: one is the Paddack Effect and the other is a spinup mechanism by the interaction of F-coronal dust with CMEs (Coronal Mass Ejections) suggested by this author. The real interplanetary particles were collected by Brownlee and associates (also known as the Brownlee Particles) from the Earth's upper atmosphere. It is anticipated that other applications of studying micron sized particles in microgravity environment using this technique will develop as the scientific community is made aware of this new technique.