scholarly journals The Visibility of Earth Transits

2004 ◽  
Vol 202 ◽  
pp. 445-447 ◽  
Author(s):  
T. Castellano ◽  
L. Doyle ◽  
D. McIntosh
Keyword(s):  
Laboratory Experiments ◽  
Ecliptic Plane ◽  
Solar Neighborhood ◽  
Geometric Condition ◽  
The Sun ◽  
Intrinsic Variability ◽  
Noise Sources ◽  
Photometric Detection ◽  
The Earth ◽  
Order Of Magnitude

The recent photometric detection of planetary transits of the solar-like star HD 209458 at a distance of 47 parsecs suggest that transits can reveal the presence of Jupiter-size planetary companions in the solar neighborhood (Charbonneau et al. 2000; Henry et al. 2000). Recent space-based transit searches have achieved photometric precision within an order of magnitude of that required to detect the much smaller transit signal of an earth-size planet across a solar-size star. Laboratory experiments in the presence of realistic noise sources have shown that CCDs can achieve photometric precision adequate to detect the 9.6 E-5 dimming of the Sun due to a transit of the Earth (Borucki et al. 1997; Koch et al. 2000). Space-based solar irradiance monitoring has shown that the intrinsic variability of the Sun would not preclude such a detection (Borucki, Scargle, Hudson 1985). Transits of the Sun by the Earth would be detectable by observers that reside within a narrow band of sky positions near the ecliptic plane, if the observers possess current Earth epoch levels of technology and astronomical expertise. A catalog of solar-like stars that satisfy the geometric condition for Earth transit visibility are presented.

The Role of Chlorine in Stratospheric Chemistry

1996 ◽  
Vol 68 (9) ◽  
pp. 1749-1756 ◽  
Author(s):  
M. J. Molina
Keyword(s):  
Laboratory Experiments ◽  
Stratospheric Ozone ◽  
The Sun ◽  
Plastic Foam ◽  
Model Calculations ◽  
Stratospheric Chemistry ◽  
Blowing Agents ◽  
Stratospheric Ozone Layer ◽  
The Earth

The chlorofluorocarbons (CFCs) are industrialchemicals used as solvents, refrigerants, plastic foam blowing agents,etc. These compounds are eventually released to the environment; theyslowly drift into the stratosphere, where they decompose, initiatinga catalytic process involving chlorine free radicals and leading toozone destruction. The stratospheric ozone layer is important for theearth's energy budget, and it shields the surface of the earth fromultraviolet radiation from the sun. Very significant depletion of theozone layer has been observed in the spring months over Antarctica duringthe last 10-15 years. Laboratory experiments, model calculations andfield measurements, which include several aircraft expeditions, haveyielded a wealth of information which clearly points to the CFCs asthe main cause of this depletion.

scholarly journals Methods to Test the “Dimming Effect” Produced by a Decrease in the Number of Photons Received from Receding Light Sources

2020 ◽  
Author(s):  
Mark Zilberman
Keyword(s):  
Light Source ◽  
Opposite Direction ◽  
Ecliptic Plane ◽  
Light Sources ◽  
The Sun ◽  
Decimal Point ◽  
Relativistic Systems ◽  
The Earth ◽  
New Models ◽  
Direction Opposite

The hypothetical “Dimming Effect” describes the change of the number of photons arriving from a moving light source per unit of time. In non-relativistic systems, the “Dimming effect” may occur due to the growing distance of light sources moving away from the receiver. This means that due to the growing distance, the photons continuously require more time to reach the receiver, which reduces the number of received photons per time unit compared to the number of emitted photons. Understandably, the proposed “Dimming effect” must be tested (confirmed or rejected) through observations. a. This article provides the formula for the calculation of “Dimming effect” values using the redshift parameter Z widely used in astronomy. b. The “Dimming effect” can possibly be detected utilizing the orbital movement of the Earth around the Sun. In accordance to the “Dimming effect”, observers on Earth will view 1.0001 more photons per time unit emitted by stars located near the ecliptic plane in the direction of the Earth orbiting the Sun. And, in contrast, observers will view only 0.9999 photons per time unit emitted by stars located near the ecliptic plane in the direction opposite to the Earth orbiting the Sun. Calculating precise measurements of the same stars within a 6-month period can possibly detect this difference. These changes in brightness are not only for specific stars, as the change in brightness takes place for all stars near the ecliptic in the direction of the Earth’s orbit around the Sun and in the opposite direction. c. The “Dimming effect” can possibly be detected in a physics laboratory using a moving light source (or mirror) and photon counters located in the direction of travel and in the opposite direction. d. In theory, Dilation of time can also be used for testing the existence of the “Dimming effect.” However, in experiments on Earth this effect appears in only the 14th digit after the decimal point and testing does not appear to be feasible. e. Why is it important to test the “Dimming effect?” If confirmed, it would allow astronomers to adjust values of "Standard Candles" used in astronomy. Since “Standard Candles” are critical in various cosmological models, the “Dimming effect” can correct models and/or reveal and support new models. If it is proved that the “Dimming effect” does not exist, it will mean that the number of photons arriving per unit of time does not depend on the speed of the light source and observer, which is not so apparent.

scholarly journals 42. Solar cosmic radiation and the interstellar magnetic field

1958 ◽  
Vol 6 ◽  
pp. 404-419 ◽  
Author(s):  
A. Ehmert
Keyword(s):  
Magnetic Field ◽  
Solar Radiation ◽  
Cosmic Radiation ◽  
The Sun ◽  
High Latitudes ◽  
Narrow Angle ◽  
The Earth ◽  
Order Of Magnitude ◽  
The Impact ◽  
Impact Zones

The increase of cosmic radiation on 23 February 1956 by solar radiation exhibited in the first minutes a high peak at European stations that were lying in direct impact zones for particles coming from a narrow angle near the sun, whilst other stations received no radiation for a further time of 10 minutes and more. An hour later all stations in intermediate and high latitudes recorded solar radiation in a distribution as would be expected if this radiation fell into the geomagnetic field in a fairly isotropic distribution. The intensity of the solar component decreased at this time at all stations according to the same hyperbolic law (~t–2).It is shown, that this decreasing law, as well as the increase of the impact zones on the earth, can be understood as the consequence of an interstellar magnetic field in which the particles were running and bent after their ejection from the sun.Considering the bending in the earth's magnetic field, one can estimate the direction of this field from the times of the very beginning of the increase in Japan and at high latitudes. The lines of magnetic force come to the earth from a point with astronomical co-ordinates near 12·00, 30° N. This implies that within the low accuracy they have the direction of the galactic spiral arm in which we live. The field strength comes out to be about 0·7 × 10–6gauss. There is a close agreement with the field, that Fermi and Chandrasekhar have derived from Hiltner's measurements of the polarization of starlight and the strength of which they had estimated to the same order of magnitude.

scholarly journals Libration of the Moon: shape of the Earth and motion of the ecliptic plane

1986 ◽  
Vol 114 ◽  
pp. 141-144
Author(s):  
M. Moons
Keyword(s):  
Gravity Field ◽  
Spherical Harmonics ◽  
Fourth Order ◽  
Center Of Mass ◽  
Ecliptic Plane ◽  
The Sun ◽  
Lunar Gravity ◽  
The Moon ◽  
Lunar Gravity Field ◽  
The Earth

Very accurate theories of the libration of the Moon have been recently built by Migus (1980), Eckhardt (1981, 1982) and Moons (1982, 1984). All of them take into account the perturbation due to the Earth and the Sun on the motion of a rigid Moon about its center of mass. Additional perturbations (influence of the planets, shape of the Earth, elasticity of the Moon, …) are also often included.We present here the perturbations due to the shape of the Earth and the motion of the ecliptic plane on our theory which already contains planetary perturbations. This theory is completely analytical with respect to the harmonic coefficients of the lunar gravity field which is expanded in spherical harmonics up to the fourth order. The ELP 2000 solution (Chapront and Chapront-Touzé, 1983) supplies us with the motion of the center of mass of the Moon.

scholarly journals Everything Is A Circle: A New Universal Orbital Model

2021 ◽  
Author(s):  
AslıPınar Tan
Keyword(s):  
Solar System ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Ecliptic Plane ◽  
The Sun ◽  
The Moon ◽  
Circular Orbits ◽  
Orbital Parameters ◽  
The Earth ◽  
Angular Velocities

Based on measured astronomical position data of heavenly objects in the Solar System and other planetary systems, all bodies in space seem to move in some kind of elliptical motion with respect to each other. According to Kepler’s 1st Law, “orbit of a planet with respect to the Sun is an ellipse, with the Sun at one of the two foci.” Orbit of the Moon with respect to Earth is also distinctly elliptical, but this ellipse has a varying eccentricity as the Moon comes closer to and goes farther away from the Earth in a harmonic style along a full cycle of this ellipse. In this paper, our research results are summarized, where it is first mathematically shown that the “distance between points around any two different circles in three dimensional space” is equivalent to the “distance of points around a vector ellipse to another fixed or moving point, as in two dimensional space”. What is done is equivalent to showing that bodies moving on two different circular orbits in space vector wise behave as if moving on an elliptical path with respect to each other, and virtually seeing each other as positioned at an instantaneously stationary point in space on their relative ecliptic plane, whether they are moving with the same angular velocity, or different but fixed angular velocities, or even with different and changing angular velocities with respect to their own centers of revolution. This mathematical revelation has the potential to lead to far reaching discoveries in physics, enabling more insight into forces of nature, with a formulation of a new fundamental model regarding the motions of bodies in the Universe, including the Sun, Planets, and Satellites in the Solar System and elsewhere, as well as at particle and subatomic level. Based on the demonstrated mathematical analysis, as they exhibit almost fixed elliptic orbits relative to one another over time, the assertion is made that the Sun, the Earth, and the Moon must each be revolving in their individual circular orbits of revolution in space. With this expectation, individual orbital parameters of the Sun, the Earth, and the Moon are calculated based on observed Earth to Sun and Earth to Moon distance data, also using analytical methods developed as part of this research to an approximation. This calculation and analysis process have revealed additional results aligned with observation, and this also supports our assertion that the Sun, the Earth, and the Moon must actually be revolving in individual circular orbits.

scholarly journals Gravity of The Sun, The Main Force Operating That Changes The Location of The Earth’s Axis of The Earth’s Mantle And, Accordingly, The Location of The Equator

2020 ◽  
pp. 188-191
Keyword(s):  
Ecliptic Plane ◽  
Earth’S Rotation ◽  
The Sun ◽  
Earth's Rotation ◽  
Earth’S Mantle ◽  
The Earth ◽  
Main Thing ◽  
A Minor ◽  
Minor Extent

The force of gravity of the sun on the earth, when the axis of the earth is found at a specific angle towards the sun in the summer and the winter, moves the earth’s mantle, including the axis of the earth’s rotation. This force is the main thing that changes the location of the axis of the earth’s rotation on the mantle of the earth and, to a minor extent or not at all, causes a change in the angle of the earth’s rotation in relation to the sun, and to the earth’s ecliptic plane.

scholarly journals Methods to Test the “Dimming Effect” Produced by a Decrease in the Number of Photons Received from Receding Light Sources

2020 ◽  
Author(s):  
M. Zilberman
Keyword(s):  
Light Source ◽  
Ecliptic Plane ◽  
Cosmological Models ◽  
Light Sources ◽  
The Sun ◽  
Decimal Point ◽  
Relativistic Systems ◽  
The Earth ◽  
New Models ◽  
Direction Opposite

Abstract The hypothetical “Dimming Effect” describes the change of the number of photons arriving from a moving light source per unit of time. In non-relativistic systems, the “Dimming effect” may occur due to the growing distance of light sources moving away from the receiver. This means that due to the growing distance, the photons continuously require more time to reach the receiver, which reduces the number of received photons per time unit compared to the number of emitted photons.Understandably, the proposed “Dimming effect” must be tested (confirmed or rejected) through observations.a. This article provides the formula for the calculation of “Dimming effect” values using the redshift parameter Z widely used in astronomy.b. The “Dimming effect” can possibly be detected utilizing the orbital movement of the Earth around the Sun. In accordance to the “Dimming effect”, observers on Earth will view 1.0001 more photons per time unit emitted by stars located near the ecliptic plane in the direction of the Earth orbiting the Sun. And, in contrast, observers will view only 0.9999 photons per time unit emitted by stars located near the ecliptic plane in the direction opposite to the Earth orbiting the Sun. Calculating precise measurements of the same stars within a 6-month period can possibly detect this difference. These changes in brightness are not only for specific stars, as the change in brightness takes place for all stars near the ecliptic in the direction of the Earth’s orbit around the Sun and in the opposite direction.c. The “Dimming effect” can possibly be detected in a physics laboratory using a moving light source (or mirror) and photon counters located in the direction of travel and in the opposite direction.d. In theory, Dilation of time can also be used for testing the existence of the “Dimming effect.” However, in experiments on Earth this effect appears in only the 14th digit after the decimal point and testing does not appear to be feasible.e. Why is it important to test the “Dimming effect?”* If confirmed, it would allow astronomers to adjust values of "Standard Candles" used in astronomy. Since “Standard Candles” are critical in various cosmological models, the “Dimming effect” can correct models and/or reveal and support new models.* If it is proved that the “Dimming effect” does not exist, it will mean that the number of photons arriving per unit of time does not depend on the speed of the light source and observer, which is not so apparent.

Reconnaissance Orbits Normal to the Ecliptic Plane

1961 ◽  
Vol 65 (606) ◽  
pp. 436-437
Author(s):  
S. W. Greenwood
Keyword(s):  
Extreme Case ◽  
Ecliptic Plane ◽  
The Sun ◽  
The Earth ◽  
Previous Note

The ecliptic plane is the plane of the orbit of the Earth round the Sun. In a previous note the velocity requirements were examined for conventional rocket vehicles to enter reconnaissance orbits around the Sun in this plane.Departure from the ecliptic plane obviously involves an increase in the velocity requirement. To some extent, all interplanetry voyages necessitate such motion, as the planets lie in planes inclined to the ecliptic. In this note, the extreme case of entry into orbits normal to the ecliptic will be considered.

scholarly journals The Next Generation Sky Survey and the Quest for Cooler Brown Dwarfs

2003 ◽  
Vol 211 ◽  
pp. 497-504 ◽  
Author(s):  
J. Davy Kirkpatrick
Keyword(s):  
Brown Dwarfs ◽  
Mass Function ◽  
Solar Neighborhood ◽  
The Sun ◽  
Next Generation ◽  
Brown Dwarf ◽  
Field Mass ◽  
The Earth ◽  
Luminosity Functions ◽  
Sky Survey

The Next Generation Sky Survey (NGSS) is a proposed NASA MIDEX mission to map the entire sky in four infrared bandpasses – 3.5, 4.7, 12, and 23 μm. The seven-month mission will use a 50-cm telescope and four-channel imager to survey the sky from a circular orbit above the Earth. Expected sensitivities will be half a million times that of COBE/DIRBE at 3.5 and 4.7 μm and a thousand times that of IRAS at 12 and 23 μm. NGSS will be particularly sensitive to brown dwarfs cooler than those presently known. Deep absorption in the methane fundamental band at 3.3 μm and a predicted 5-μm overluminosity will produce uniquely red 3.5-to-4.7 μm colors for such objects. For a limiting volume of 25 pc, NGSS will completely inventory the Solar Neighborhood for brown dwarfs as cool as Gl 229B. At 10 pc, the census will be complete to 500 K. Assuming a field mass function with α = 1, there could be one or more brown dwarfs warmer than 150 K lying closer to the Sun than Proxima Centauri and detectable primarily at NGSS wavelengths. NGSS will enable estimates of the brown dwarf mass and luminosity functions to very cool temperatures and will provide both astrometric references and science targets for NGST.

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