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1.
A summary is given about the Minor Planet survey performed in 1984 on Tautenburg Schmidt plates. We discovered 84 planets and calculated 205 positions for them. Among them are 17 numbered planets, 16 already earlier observed and 51 new planets with provisional designations. Tautenburg observations could give a tribute to seven planets numbered in the period of this report. The planet 1964 EC discovered in Tautenburg has received the permanent number (3181). In honor of Dr. PAUL AHNERT (*22. 11. 1897) this planet obtained the name Ahnert. 相似文献
2.
F. Brngen 《Astronomische Nachrichten》1990,311(2):123-131
A summary is given about the minor planet survey performed in 1988 on Tautenburg Schmidt plates. There were discovered 386 asteroids and 1218 positions were calculated for them. These are 87 numbered objects and 299 asteroids with provisional designations, 252 of them have new designations. Tautenburg observations contributed to 40 planets numbered in the period of this report, including eight discovered in Tautenburg. 相似文献
3.
A summary is given about the Minor Planet survey performed in 1982 on Tautenburg Schmidt plates. We discovered 229 planets and calculated 643 positions for them. Tautenburg observations have given a tribute to ten planets numbered in 1982. Planet (2424) discovered by us has received the name Tautenburg. 相似文献
4.
F. B
rngen 《Astronomische Nachrichten》1988,309(1):53-55
A summary is given about the Minor Planet survey performed in 1986 on Tautenburg Schmidt plates. There were discovered 129 asteroids and calculated 312 positions for them. These are 29 numbered objects and 100 asteroids with provisional designations, six of them have no new designations. Tautenburg observations could give a tribute to five planets numbered in the period of this report, including the asteroid 1981 VW1 discovered in Tautenburg which received the number (3499) and the name Hoppe. 相似文献
5.
F. Brngen 《Astronomische Nachrichten》1987,308(2):139-141
A summary is given about the Minor Planet survey performed in 1985 on Tautenburg Schmidt plates. There were discovered 95 asteroids and calculated 168 positions for them. These are 20 numbered objects and 75 asteroids with provisional designations, two of them have no new designation. Tautenburg observations could give a tribute to twelve planets numbered in the period of this report. Two asteroids discovered in Tautenburg have received numbers and names: (3245) Jensch = 1973 UL5 and (3338) Richter = 1973 UX5. 相似文献
6.
Here is a summary about the Minor Planet survey performed in 1981 on Tautenburg Schmidt plates. We discovered 294 planets and calculated 614 positions for them. 相似文献
7.
F. B
rngen 《Astronomische Nachrichten》1996,317(3):217-223
A summary is given about the Minor Planet survey performed in 1994 on Tautenburg Schmidt plates. 321 asteroids were observed and 1171 positions are calculated for them. These are 200 asteroids with provisional designations (102 of them have new designations) and 121 numbered objects. Tautenburg observations could give a tribute to 73 planets numbered in the period of this report. Fourteen Tautenburg asteroids have been numbered. 相似文献
8.
F. Brngen 《Astronomische Nachrichten》1989,310(1):79-84
Es wird eine Übersicht gegeben über die im Jahr 1987 auf Tautenburger Schmidtplatten gefundenen Kleinen Planeten. Es wurden 290 Objekte entdeckt und für diese 845 Positionen gerechnet. Es handelt sich um 75 numerierte Objekte, von denen drei auf der kritischen Liste von EMP 1988 stehen, sowie um 215 Planetoiden mit provisorischen Bezeichnungen. Von letzteren erhielten 191 neue Bezeichnungen. Für 17 im Berichtszeitraum numerierte Planeten haben Tautenburger Beobachtungen einen Beitrag geleistet. Darunter sind zwei in Tautenburg entdeckte Planetoiden: 1967 GF1 erhielt die Nummer (3539) und den Namen Weimar, der Trojaner 1973 UF5 die Nummer (3540) und den Namen Protesilaos. A summary is given about the Minor Planet survey performed in 1987 on Tautenburg Schmidt plates. There were discovered 290 asteroids and calculated 845 positions for them. These are 75 numbered objects and 215 asteroids with provisional designations, 191 of them have new designations. Tautenburg observations could give a tribute to 17 planets numbered in the period of this report, including two asteroids discovered in Tautenburg: 1967 GF1 received the number (3539) and the name Weimar, the Trojans 1973 UF5 the number (3540) and the name Protesilaos. 相似文献
9.
F. Brngen 《Astronomische Nachrichten》1995,316(3):187-194
A summary is given about the Minor Planet survey performed in 1993 on Tautenburg Schmidt plates. 392 asteroids were observed and 1462 positions are calculated for them. These are 297 asteroids with provisional designations (217 of them have new designations) and 95 numbered objects. Ten new designations originate from the KSO-ARI-Survey IV. Tautenburg observations could give a tribute to 50 planets numbered in the period of this report. Six Tautenburg asteroids have been numbered (Tab. 3). 相似文献
10.
自1995年第一颗类太阳恒星周围的系外行星发现以来,随着已发现的系外行星数目的增多,对系外行星性质的统计分析变得重要和有意义。截至2011年6月9日,共发现系外行星555颗。以这些系外行星的轨道参数为依据,对系外行星的性质进行统计分析,得出了一些有意义的结论。同时简要介绍现有的行星形成与演化模型并依据得出的行星统计性质对其进行检验,这对于系外行星的进一步探测具有一定的指导作用。 相似文献
11.
《Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science》1999,24(5):553-556
Giant planets in circumstellar disks can migrate inward from their initial (formation) positions at several AUs. Inward radial migration of the planet is caused by torques between the planet and the disk; outward radial migration of the planet is caused by torques between the planet and the spinning star, and by torques due to Roche lobe overflow and consequent mass loss from the planet. We present self-consistent numerical considerations of the problem of migrating giant planets by summing torques on planets for various physical parameters of the disk and of planets. We find that Jupiter-mass planets can stably arrive and survive at small heliocentric distances, thus reproducing observed properties of some of the recently discovered extra-solar planets. The range of fates of massive planets is broad, and some perish by losing all their mass onto the central star during Roche lobe overflow, while others survive for the lifetime of the central star. Surviving planets cluster into two groups when examined in terms of final mass and final heliocentric distance: those which have lost mass and those which have not. Some of the observed extrasolar planets fall into each of these two exclusive classes. We also find that there is an inner boundary for planets' final heliocentric distances, caused by tidal torques with the central star. Planets in small orbits are shown to be stable against atmospheric loss. 相似文献
12.
13.
We calculate the evolution of planets undergoing a strong tidal encounter using smoothed particle hydrodynamics (SPH), for a range of periastron separations. We find that outside the Roche limit, the evolution of the planet is well-described by the standard model of linear, non-radial, adiabatic oscillations. If the planet passes within the Roche limit at periastron, however, mass can be stripped from it, but in no case do we find enough energy transferred to the planet to lead to complete disruption. In light of the three new extrasolar planets discovered with periods shorter than two days, we argue that the shortest-period cases observed in the period-mass relation may be explained by a model whereby planets undergo strong tidal encounters with stars, after either being scattered by dynamical interactions into highly eccentric orbits, or tidally captured from nearly parabolic orbits. Although this scenario does provide a natural explanation for the edge found for planets at twice the Roche limit, it does not explain how such planets will survive the inevitable expansion that results from energy injection during tidal circularization. 相似文献
14.
B. Funk E. Pilat-Lohinger R. Dvorak F. Freistetter B. Èrdi 《Celestial Mechanics and Dynamical Astronomy》2004,90(1-2):43-50
Since the first extrasolar planet was discovered about 10 years ago, a major point of dynamical investigations was the determination
of stable regions in extrasolar planetary systems where additional planets may exist. Using numerical methods, we investigate
the dynamical stability in known multiple planetary systems (HD74156, HD38529, HD168443, HD169830) with special interest on
the region between the two known planets and on the mean motion resonances inside this region. As a dynamical model we take
the restricted 4-body problem containing the host star, the two planets and massless test-planets. For our numerical integrations,
we used the Lie-integrator and additionally the Fast Lyapunov Indicators as a tool for detecting chaotic motion. We also investigated
the inner resonances with the outer planet and the outer resonances with the inner planet with test-planets located inside
the resonances. 相似文献
15.
We have investigated obliquity variations of possible terrestrial planets in habitable zones (HZs) perturbed by a giant planet(s) in extrasolar planetary systems. All the extrasolar planets so far discovered are inferred to be jovian-type gas giants. However, terrestrial planets could also exist in extrasolar planetary systems. In order for life, in particular for land-based life, to evolve and survive on a possible terrestrial planet in an HZ, small obliquity variations of the planet may be required in addition to its orbital stability, because large obliquity variations would cause significant climate change. It is known that large obliquity variations are caused by spin-orbit resonances where the precession frequency of the planet's spin nearly coincides with one of the precession frequencies of the ascending node of the planet's orbit. Using analytical expressions, we evaluated the obliquity variations of terrestrial planets with prograde spins in HZs. We found that the obliquity of terrestrial planets suffers large variations when the giant planet's orbit is separated by several Hill radii from an edge of the HZ, in which the orbits of the terrestrial planets in the HZ are marginally stable. Applying these results to the known extrasolar planetary systems, we found that about half of these systems can have terrestrial planets with small obliquity variations (smaller than 10°) over their entire HZs. However, the systems with both small obliquity variations and stable orbits in their HZs are only 1/5 of known systems. Most such systems are comprised of short-period giant planets. If additional planets are found in the known planetary systems, they generally tend to enhance the obliquity variations. On the other hand, if a large/close satellite exists, it significantly enhances the precession rate of the spin axis of a terrestrial planet and is likely to reduce the obliquity variations of the planet. Moreover, if a terrestrial planet is in a retrograde spin state, the spin-orbit resonance does not occur. Retrograde spin, or a large/close satellite might be essential for land-based life to survive on a terrestrial planet in an HZ. 相似文献
16.
We represent 266 positions of 77 minor planets determined from plates taken in 1972 and in 1979–1980 with the Schmidt telescope 1340/2000/4000 of KARL SCHWARZSCHILD Observatory Tautenburg. 相似文献
17.
The TrES‐2 system harbors one planet which was discovered with the transit technique. In this work we investigate the dynamical behavior of possible additional, lower‐mass planets. We identify the regions where such planets can move on stable orbits and show how they depend on the initial eccentricity and inclination. We find, that there are stable regions inside and outside the orbit of TrES‐2b where additional, smaller planets can move. We also show that those planets can have a large orbital inclination which makes a detection with the transit technique very difficult (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
18.
Since 1995, more than 200 extra-solar planets have been discovered, demonstrating not only that planetary systems are common, but also that planets may come in a large variety of flavors. As the number of detections grows, statistical studies of the properties of exoplanets and their host stars can be conducted to unravel some of the key physical and chemical processes leading to the formation of planetary systems. In this paper we describe the major techniques used to search for extra-solar planets. In particular, we discuss in more detail the radial-velocity and the transit techniques, responsible for the discovery of the bulk of the known planets orbiting solar-type stars. We then present the main results from the planet surveys, describing the global properties of the newfound worlds. 相似文献
19.
Es wird eine Übersicht gegeben über die im Jahr 1992 auf Tautenburger Schmidtplatten gefundenen Kleinen Planeten. Es wurden 518 Objekte beobachtet und für diese 2396 Positionen gerechnet. Es handelt sich um 408 Planetoiden mit provisorischer Bezeichnung, unter denen 274 neu vergebene Bezeichnungen sind, sowie um 110 numerierte Objekte. Für 172 Tautenburger Objekte wurden Bahnen aus einer Opposition gerechnet. Für 55 im Berichtszeitraum numerierte Planeten haben Tautenburger Positionen einen Beitrag geleistet. Acht Tautenburger Planetoiden wurden numeriert (Tab. 3). A summary is given about the Minor Planet survey performed in 1992 on Tautenburg Schmidt plates. 518 asteroids were observed and 2396 positions are calculated for them. These are 408 asteroids with provisional designations (274 of them have new designations) and 110 numbered objects. One-opposition orbits have been computed for 172 Tautenburg asteroids. Tautenburg observations could give a contribution to 55 planets numbered in the period of this report. Eight Tautenburg asteroids have been numbered (Tab. 3). 相似文献
20.
J. R. Donnison 《Earth, Moon, and Planets》2014,113(1-4):73-97
Limits are placed on the range of orbits and masses of possible moons orbiting extrasolar planets which orbit single central stars. The Roche limiting radius determines how close the moon can approach the planet before tidal disruption occurs; while the Hill stability of the star–planet–moon system determines stable orbits of the moon around the planet. Here the full three-body Hill stability is derived for a system with the binary composed of the planet and moon moving on an inclined, elliptical orbit relative the central star. The approximation derived here in Eq. (17) assumes the binary mass is very small compared with the mass of the star and has not previously been applied to this problem and gives the criterion against disruption and component exchange in a closed form. This criterion was applied to transiting extrasolar planetary systems discovered since the last estimation of the critical separations (Donnison in Mon Not R Astron Soc 406:1918, 2010a) for a variety of planet/moon ratios including binary planets, with the moon moving on a circular orbit. The effects of eccentricity and inclination of the binary on the stability of the orbit of a moon is discussed and applied to the transiting extrasolar planets, assuming the same planet/moon ratios but with the moon moving with a variety of eccentricities and inclinations. For the non-zero values of the eccentricity of the moon, the critical separation distance decreased as the eccentricity increased in value. Similarly the critical separation decreased as the inclination increased. In both cases the changes though very small were significant. 相似文献