Measuring Earth’s axial tilt with a telescope

2017 ◽  
Vol 52 (3) ◽  
pp. 033003 ◽  
Author(s):  
R Suat Isildak ◽  
H Asuman Küçüközer ◽  
Hakan Isik
Keyword(s):  
Author(s):  
Suresh K

We are on a planet that orbits the Sun which emits a huge amount of energy. The climate we experience is a result of an energy gradient across Earth and an imbalance in energy across the world due to axial tilt of Earth rotation.


Solar Physics ◽  
1993 ◽  
Vol 145 (1) ◽  
pp. 105-109 ◽  
Author(s):  
Robert F. Howard
Keyword(s):  

2017 ◽  
Vol 870 ◽  
pp. 215-222
Author(s):  
Vu Van Duy ◽  
Vu Toan Thang ◽  
Pham Van Hung

Calibration for torque measurement devices has become a great demand in many industrial areas. The most important in a calibration process is decreasing its uncertainty. This paper presents in building formula to evaluate the measurement uncertainty for torque standard machine using air rotary bearing which is experimented at the Hanoi University of Science and Technology. The uncertainty of the device is composed of the uncertainty of the component elements such as arm length, load, friction torque, axial tilt, vibration load...etc. Based on them the formula is built to estimate the measurement uncertainty of torque standard machine, find out factors that affect most to the measurement uncertainty value, therefore it can benefit the further researches to improve the accuracy of the torque standard machine.


2020 ◽  
Vol 12 (2) ◽  
pp. 1
Author(s):  
Puthalath Koroth Raghuprasad

This study identifies the unique features accompanying the phenomenon of synchronous rotation of the major (proximal) satellites of the gas giants and the earth’s moon, and the special features leading to the ‘negative’ rotation of Venus, Uranus and Pluto, as well as the most peripheral small satellites of the gas giants. Such features help us understand how these phenomena occur but also, by combining all of the observations help explain other (regular) planetary motions as well. In the synchronously rotating satellites, the salient features are the satellites’ low axial tilts and both the orbital speed and the axial rotation speed increasing with proximity to the mother body. In “negative” rotation, axial tilts are in excess of 120° and the axial rotation speeds are significantly delayed; this delay is most pronounced in Venus, which has an axial tilt of -174°. A scrutiny of the orbital parameters of all the satellites of the gas giants alone will yield sufficient data to propose a working hypothesis of how mutual gravitation, combined with spin (axial rotation and orbital motion), the distance from the mother, and centrifugal force can explain all motions. It confirms our belief that the process of planetary motions is a continuum from the synchronous, through degrees of non-synchronicity (or regular orbits), to the negative rotations, all depending on the degree of influence from mother bodies, as a product of distances from them. Thus, the nearest large satellites with the least axial tilts display synchronous rotation. Those satellites that are intermediate in distance from the mother show nonsynchronous axial rotation and correspondingly slower orbital speeds. The small peripheral satellites display axial tilts over 120 degrees and rotate negatively. In all these orbital motions, centrifugal force is the crucial restraining influence; lest, the orbiting bodies will tend to fall into the mother bodies. How all these pieces of the puzzle fit together in the orderly movements of bodies in the universe is the underlying theme of this article.


2018 ◽  
Vol 14 (S345) ◽  
pp. 291-292
Author(s):  
Yutong Shan ◽  
Gongjie Li

AbstractObliquity (axial tilt) and its variability could play an important role in the climate and habitability of a planet. We explore the spin-axis dynamics of two specific habitable zone exoplanets, Kepler-62f and Kepler-186f, using numerical and analytical techniques. Based on our current understanding of their orbital architecture, we find that, in contrast with the typical conditions in the Solar System, Kepler-62f and 186f should have low obliquity variations except in fine-tuned conditions. Extra undetected planetary companions and/or the existence of a satellite could either stabilize or destabilize obliquities at a variety of values.


Author(s):  
Gabriel E. Soto ◽  
Stephen J. Young ◽  
Maryann E. Martone ◽  
Thomas J. Deerinck ◽  
Stephan Lamont ◽  
...  

One of the limitations of electron microscopy has been the requirement for very thin samples to allow penetration of the electron beam. It is often the case that structures of interest are not contained within a single thin section. In these cases, serial sectioning techniques are required to reconstruct the object in its entirety. The use of higher voltage electron microscopes has allowed researchers to examine specimens up to fifty times thicker than those suitable for a conventional TEM. However, images from thick sections are often difficult to interpret as the electron micrograph is essentially a projection of the overlapping material within the section. The method of computerized axial tilt electron microscopic tomography offers the potential to visualize and analyze information contained in a thick section by deriving a three dimensional volume from a series of projections acquired by collecting images of the specimen at successive tilt increments about the Y axis. Unfortunately there are practical limitations to the resolution that can be obtained using this technique with very thick sections. Resolution of the tomogram increases with finer tilt sampling and an increased range of tilts but decreases with section thickness.


Solar Physics ◽  
1996 ◽  
Vol 169 (2) ◽  
Author(s):  
RobertF. Howard
Keyword(s):  

Solar Physics ◽  
1991 ◽  
Vol 136 (2) ◽  
pp. 251-262 ◽  
Author(s):  
Robert F. Howard
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document