Speckle interferometry applied to asteroids and other solar system objects Download PDF EPUB FB2
Get this from a library. Speckle interferometry applied to asteroids and other solar system objects: final report for NAGW August - July [Jack D Drummond; E Keith Hege; United States. National Aeronautics and Space Administration.]. Electronic speckle pattern interferometry (ESPI), also known as TV Holography, is a technique which uses laser light, together with video detection, recording and processing to visualise static and dynamic displacements of components with optically rough surfaces.
The visualisation is in the form of fringes on the image where each fringe normally represents a displacement of half. TMC are good objects for speckle interferometric ob-servations. SPECKLE INTERFEROMETRY AT TELESCOPES OF OBSERVATORIO ASTRONOMICO NACIONAL Speckle interferometry is the main method for ac-curate astrometric measurements of binary and mul-tiple stars.
We chose this technique because it is simple and less expensive than other. Basically, the instrument records the accumulated power spectrum of target objects (in this case asteroids) and nearby stars used as calibrators to derive the speckle transfer function (STF).
This is the Fourier transform of the autocorrelation of the point spread function and depends on both the telescope aperture and the atmospheric Cited by: The speckle interferometry method has been applied to the observations of some binary and multiple asteroids and asteroids that were suspected of being binary or multiple in following works [Roberts et al, ; Cellino et al, ].
Obtained observations allowed to determine the shapes and the sizes of the by: 2. Speckle interferometry of Herculina performed on January 17yields triaxial ellipsoid dimensions of ( ± 14) × ( ± 12) × ( ± 12) km, and a north pole for the asteroid within 7° of RA = 7 b 47 m and DEC = −39° (ecliptic coordinates γ = ° β = −59°).
In addition, a “spot” some 75% brighter than the rest of the asteroid is inferred from both speckle Cited by: Speckle interferometry measurements of the asteroids Hygiea and Eunomia Article (PDF Available) in Astronomy and Astrophysics (1).
Results of speckle observations at the m SOAR telescope in ( measures of systems, 27 non-resolutions) are reported. The aim is Author: Andrei Tokovinin. Interferometry is a family of techniques in which waves, usually electromagnetic waves, are superimposed, causing the phenomenon of interference, which is used to extract information.
Interferometry is an important investigative technique in the fields of astronomy, fiber optics, engineering metrology, optical metrology, oceanography, seismology, spectroscopy (and its. described. This instrument was tested at the SOAR 4-m telescope in the speckle-interferometry regime.
The data were processed by the standard speckle algorithm permitting derivation of binary-star parameters. We observed 29 objects with separations from 21 mas to ″, mostly southern binaries with known orbits.
Some pairs require orbit Cited by: A simple method is presented for the measurement of in-plane rotation (angle and sign) of an object by use of the conventional in-plane sensitive electronic speckle pattern interferometry technique combined with the two-wavelength laser diode method.
The advantage of this method is that it can be used to measure the angle of rotation in a simple way by determination of. Diffraction-limited images, of resolution many times finer than what is ordinarily obtainable through large earth-bound telescopes, can be obtained by first measuring the modulus of the Fourier transform of an object by the method of Labeyrie's stellar speckle interferometry, and then reconstructing the object by an iterative by: 8.
The C-type (chondrite) asteroids are most common, probably consist of clay and silicate rocks, and are dark in appearance.
They are among the most ancient objects in the solar system. The S-types ("stony") are made up of silicate materials and. The parameter characterizing nonisoplanatic effects in speckle interferometry can be measured by observing double stars. An experimental method is developed which permits estimation of this parameter in the presence of inherently large photon and detector noises as well as unequal double-star component brightnesses.
Data are presented on five double stars ranging from. Pluto Articles (sorted by author) This list contains articles. Measurement of the diameter of Pluto by speckle interferometryAstrophysical Journal, Part 2 - Letters to the Editor, vol.
Dec. 1,p. Speckle interferometry applied to asteroids and other solar system objectsIn NASA, Washington Reports of. interferometry at radio wavelengths, interferometry in the frequency domain applied to spectroscopy, or more general electro-optics theoretical and laboratory research.
Spatial interferometry in astronomy at optical wavelengths, with its roots in the 19th Century, is nonetheless a comparatively immature field. The active period of. The book “Holographic and Speckle Interferometry” by Robert Jones and Catherine Wykes  gives a detailed introduction to the field of Speckle interferometry, and a detailed introduction to the light-in-flight technique, which is used with speckle metrology in this thesis can be found in the book.
Dudinov V.N. et al. () Speckle Interferometry with the BTA Telescope. In: Humphries C.M. (eds) Instrumentation for Astronomy with Large Optical Telescopes.
Astrophysics and Space Science Library (A Series of Books on the Recent Developments of Space Science and of General Geophysics and Astrophysics Published in Connection with the Journal Cited by: 1.
Fig. EV5 radar echo power received by Green Bank as a function of time on Decem with s resolution, showing speckles moving over the station. Given a speckle scale of km, the average speckle duration of ± s gives a speckle v elocity of ± km/s, as expected from EV5's distance and rotation rate.
Optical interferometry in astronomy is resolved by an interferometer if the fringe contrast goes to zero at the longest baseline. As motivated in the last paragraph, this occurs when the angular separation is λ/2b, where b is the Size: 2MB.
Astronomers have invented a clever technique to improve telescope performance. This trick makes it appear as if we have a bigger telescope than we really do.
The technique, called interferometry, uses widely separated telescopes in a special arrangement to increase the resolution of fine details in astronomical objects.
In our earlier discussion of telescopes, we. () “Ninth planet in our solar system” Speaker – Kat Volk. There is intriguing evidence for a ninth planet in our solar system says Kat Volk, a post-doctoral researcher in the UA Department of Planetary on this project.
If planet nine were to exist, it would have a huge impact on the study of the solar system. Other articles where Speckle interferometry is discussed: star: Stellar radii: A more recent method, called speckle interferometry, has been developed to reproduce the true disks of red supergiant stars and to resolve spectroscopic binaries such as Capella.
The speckle phenomenon is a rapidly changing interference-diffraction effect seen in a highly magnified diffraction image.
Planetary Radar Astronomy. INTRODUCTION. Radar studies of the planets and smaller bodies in the solar system are driven by the desire to understand how our solar system formed and evolved and, in the case of near-Earth asteroids (NEAs), by the concern that some of these small objects may pose a threat to Earth.
Astronomical interferometers can produce higher resolution astronomical images than any other type of telescope. At radio wavelengths, image resolutions of a few micro-arcseconds have been obtained, and image resolutions of a fractional milliarcsecond have been achieved at visible and infrared simple layout of an astronomical interferometer is a parabolic.
We report the results of speckle-interferometric observations of high proper-motion metalpoor stars made with the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences. We resolve eight objects—G, G, BD+19° A, G, G, G, G, and G—into individual components and we Cited by: 6.
Purchase Basics of Interferometry - 1st Edition. Print Book & E-Book. ISBNaligned in the direction of speckle motion or spaced much closer together than the speckle scale, we can still determine the target’s sense of rotation. Speckles from prograde-rotating asteroids will move from east to west, and those from retrograde rotators from west to east.
Thus the motion of the speckle pattern indicates the sense of. speckle interferometry as it lacked the acquisition accuracy required by our acquisition system. However, the east auxiliary is a much more accurate telescope in terms of control (Harshaw et al.
) and so was chosen for our speckle observing run in May of Use of the East Auxiliary Telescope introduced a new set of : Richard Harshaw, Jimmy Ray, David Douglass, Lori Prause, Russell Genet.
The possibility of this method application to the binary and multiple asteroid systems investigations had been expressed by various researchers as far back as 20 years ago (Prokof’eva and Tarashchuk, ).The speckle interferometry method has been applied to the observations of some binary and multiple asteroids and asteroids that were.
Interferometry (in this case “astronomical interferometry”) is a technique that astronomers use to obtain the resolution of a large telescope by using multiple smaller telescopes.
The electromagnetic radiation collected at each of a number of separate small telescopes is combined to re-create the image that would have been obtained with the.In LIGO, this causes one arm of the interferometer to get longer while the other gets shorter, then vice versa, back and forth as long as the wave is passing.
The technical term for this motion is "Differential Arm" motion, or differential displacement, since the arms are simultaneously changing lengths in opposing ways, or differentially. Speckle interferometry is a method for attainment high angular resolution using full aperture of the large telescope.
We give a brief description of the main principles of the method and the history of its development at large telescopes. The main fields of application of the method are the binary and multiple star research, study of the circumstellar gas and dust Author: Yuri Balega.