16 research outputs found
Master Robotic Net
The main goal of the MASTER-Net project is to produce a unique fast sky
survey with all sky observed over a single night down to a limiting magnitude
of 19 - 20mag. Such a survey will make it possible to address a number of
fundamental problems: search for dark energy via the discovery and photometry
of supernovas (including SNIa), search for exoplanets, microlensing effects,
discovery of minor bodies in the Solar System and space-junk monitoring. All
MASTER telescopes can be guided by alerts, and we plan to observe prompt
optical emission from gamma-ray bursts synchronously in several filters and in
several polarization planes.Comment: 10 pages, 8 figure
Transient detections and other real-time data processing from wide-field chambers MASTER-VWF
At present time Robotic observatory making is of current importance. Having a
large field of view and being able to point at anywhere, Robotic astronomical
systems are indispensable when they looking for transients like grb, supernovae
explosions, novae etc, as it's impossible in these cases to foresee what you
should point you telescope at and when. In work are described prompt GRB
observations received on wide-field chambers MASTER-VWF, and also methods of
the images analysis and transients classifications applied in real-time data
processing in this experiment. For 7 months of operation 6 synchronous
observations of gamma-ray burst had been made by MASTER VWF in Kislovodsk and
Irkutsk. In all cases a high upper limits have been received (see tabl \ref
{tab_grbwf} and fig. \ref {allgrb}).Comment: 21 pages, 21 figure, 2 tables, Advances in Astronomy in pres
Transient Detections and Other Real-Time Data Processing from MASTER-VWF Wide-Field Cameras
Another Shipment of Six Short-Period Giant Planets from TESS
We present the discovery and characterization of six short-period, transiting
giant planets from NASA's Transiting Exoplanet Survey Satellite (TESS) --
TOI-1811 (TIC 376524552), TOI-2025 (TIC 394050135), TOI-2145 (TIC 88992642),
TOI-2152 (TIC 395393265), TOI-2154 (TIC 428787891), & TOI-2497 (TIC 97568467).
All six planets orbit bright host stars (8.9 <G< 11.8, 7.7 <K< 10.1). Using a
combination of time-series photometric and spectroscopic follow-up observations
from the TESS Follow-up Observing Program (TFOP) Working Group, we have
determined that the planets are Jovian-sized (R = 1.00-1.45 R),
have masses ranging from 0.92 to 5.35 M, and orbit F, G, and K stars
(4753 T 7360 K). We detect a significant orbital eccentricity
for the three longest-period systems in our sample: TOI-2025 b (P = 8.872 days,
= ), TOI-2145 b (P = 10.261 days, =
), and TOI-2497 b (P = 10.656 days, =
). TOI-2145 b and TOI-2497 b both orbit subgiant host
stars (3.8 g 4.0), but these planets show no sign of inflation
despite very high levels of irradiation. The lack of inflation may be explained
by the high mass of the planets; M (TOI-2145
b) and M (TOI-2497 b). These six new discoveries
contribute to the larger community effort to use {\it TESS} to create a
magnitude-complete, self-consistent sample of giant planets with
well-determined parameters for future detailed studies.Comment: 20 Pages, 6 Figures, 8 Tables, Accepted by MNRA
TOI-1259Ab – a gas giant planet with 2.7 per cent deep transits and a bound white dwarf companion
We present TOI-1259Ab, a 1.0RJup gas giant planet transiting a 0.71R⊙ K-dwarf on a 3.48 d orbit. The system also contains a bound white dwarf companion TOI-1259B with a projected distance of ∼1600 au from the planet host. Transits are observed in nine TESS sectors and are 2.7 per cent deep – among the deepest known – making TOI-1259Ab a promising target for atmospheric characterization. Our follow-up radial velocity measurements indicate a variability of semiamplitude , implying a planet mass of 0.44MJup. By fitting the spectral energy distribution of the white dwarf, we derive a total age of Gyr for the system. The K dwarf’s light curve reveals rotational variability with a period of 28 d, which implies a gyrochronology age broadly consistent with the white dwarf’s total age
A Possible Alignment Between the Orbits of Planetary Systems and their Visual Binary Companions
Astronomers do not have a complete picture of the effects of wide-binary companions (semimajor axes greater than 100 au) on the formation and evolution of exoplanets. We investigate these effects using new data from Gaia Early Data Release 3 and the Transiting Exoplanet Survey Satellite mission to characterize wide-binary systems with transiting exoplanets. We identify a sample of 67 systems of transiting exoplanet candidates (with well-determined, edge-on orbital inclinations) that reside in wide visual binary systems. We derive limits on orbital parameters for the wide-binary systems and measure the minimum difference in orbital inclination between the binary and planet orbits. We determine that there is statistically significant difference in the inclination distribution of wide-binary systems with transiting planets compared to a control sample, with the probability that the two distributions are the same being 0.0037. This implies that there is an overabundance of planets in binary systems whose orbits are aligned with those of the binary. The overabundance of aligned systems appears to primarily have semimajor axes less than 700 au. We investigate some effects that could cause the alignment and conclude that a torque caused by a misaligned binary companion on the protoplanetary disk is the most promising explanation
CREATION OF HIGH-PRECISION ANALYTICAL THEORY OF MOTION OF EARTH ARTIFICIAL SATELLITES (EAS)
There the differential equations of motion have been studied in view to creation of algorithms for representation of EAS motion in the analytical foRm. The manner to calculate and to use the characteristics of staging orbit, the software package to analyse the observation of EAS with the flight altitudes from 800 to 40000 km have been developedAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio
Features of geosynchronous space objects motion near 75oE
Spacecrafts in geostationary orbit are subject to a complex set of disturbances that involve changes in orbital parameters. Corrections to the orbit are regularly carried out to keep the satellite at a given point of standing. The geostationary satellites must be moved to the disposal orbit after finishing their service life. Otherwise they begin to move towards the nearest stable point of libration and to make oscillatory movements in longitude, regularly approaching different satellites, which creates a threat of collision. The theory of motion for large space objects is well developed and their movement is predictable. However, small-sized fragments of space debris, are highly susceptible to difficult-to-predict non-gravitational disturbances. It is important to study the orbital motion of space objects that perform libration movements near 75∘E,where the majority of Russian working geostationary satellites are located. Optical measurements at observatories in Zvenigorod, at the Terskol peak and on Sanglokh Mount (Tajikistan) of some of the librational geosynchronous objects were performed. Results of the analysis of some of the geosynchronous small-sized fragments are given