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1.
第23太阳活动周不会是强活动周 总被引：5，自引：1，他引：4
利用最新的太阳黑子观测资料和线性相关统计模式,对第２３太阳活动周的极大月平滑黑子相对数和黑子数物极大年均值进行预测,预报因子分别是每个太阳周上升相第２６个月的月平滑黑子相对数和第三年的黑子数年均值,预测结果表明,第２３周太阳黑子数的极大值不会高,极大月平滑黑子相对为１１５．４±１４．９,极大年均值为１１８．９±１１．６,平滑黑子数极大不会出现在１９９９年,很可能出现在２０００年。 相似文献
2.
张桂清 《中国天文和天体物理学报》1999,(2)
利用最新的太阳黑子观测资料和线性相关统计模式,对第２３太阳活动周的极大月平滑黑子相对数和黑子数的极大年均值进行预测．预报因子分别是每个太阳周上升相第２６个月的月平滑黑子相对数和第三年的黑子数年均值．预测结果表明,第２３周太阳黑子数的极大值不会高,极大月平滑黑子相对数为１１５．４±１４．９,极大年均值为１１８．９±１１．６．平滑黑子数极大不会出现在１９９９年,很可能出现在２０００年． 相似文献
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4.
LSTAR模型用于太阳黑子相对数预测的初步研究 总被引：1，自引：0，他引：1
郑大伟 《中国科学院上海天文台年刊》1993,(14):164-169
本采用了1891年至1988年期间的太阳黑子相对数的月均值资料序列，进行了用非线性时间序列分析的跳步门限自回归（LSTAR）模型作预测的研究。三年的预测结果表明，预测值与实际月均值之间的相对误差约为17％，预测值的平滑值与实际月均值的平滑值之间的相对误差接近8％左右，该方法预测的初步尝试结果表明，1992年每月的太阳黑子相对数仍将可能稳定在100以上，第22周太阳黑子相对数的谷值期将可能发生在1996年。 相似文献
5.
本文分析了第２１ 、２２ 、２３ 太阳活动周的上升期２３ 个月（ 月均值） 太阳黑子资料。结果表明：太阳黑子相对数和面积南北不对称。２３ 周的太阳黑子相对数和面积（２３ 个月的平均） 高于２２ 周,但低于２１ 周。我们估计第２３ 周峰年为２０００ 年３ 月或１９９９ 年１２ 月。 相似文献
6.
利用压强改正莫斯科中子监测值,对第２３太阳活动周的未来发展趋势作了预测,推测第 ２３周太阳活动和第 ２２周相当,约在 ２００１年达到 １５１± １６的极大月平均黑子相对数． 相似文献
7.
简单介绍了灰色拓扑理论的原理,以1944—2008年各年的太阳黑子数年均值为基础,利用灰色拓扑预测方法建立了灰色拓扑预测模型群,并应用该模型群对第24、25和26太阳活动周自2009年到2039年共30 yr的太阳黑子数年均值进行了预测.预测结果表明,太阳黑子数极大年将可能出现在2014年、2023年和2033年,峰值分别为90、110和130,推测将在2017年、2025年和2039年达到极小值,极小值分别为20、20和10. 相似文献
8.
太阳黑子相对数的分维研究 总被引：4，自引：0，他引：4
本文用非线性动力系统理论控制了现代太阳周（１８５０年１月－１９９２年５月）黑子相对数月平均变化的动力行为和可预报性，计算了它的分维数。结果表明，太阳黑子数月均变化是一个复杂的低维浑沌系统，可用有限个参数描述，所需变量至少为３个，最多为７个，本文还讨论了黑子数月均值的可预报时间尺度，平均可预报时间尺度为１５０个月，本文建议利用最小二乘直线拟合的最小方差来判定最佳无标度区，所得分维数较客观，并简要讨论 相似文献
9.
对云南天文台１９６４年１月至１９９６年１２月期间的太阳黑子相对数与《Ｓｏｌａｒ－ＧｅｏｐｈｙｓｉｃａｌＤａｔａ》上对应的数据进行了比较,结果发现,云南天文台的黑子相对数,在整体上及各个太阳活动周内与《Ｓｏｌａｒ－ＧｅｏｐｈｙｓｉｃａｌＤａｔａ》上的数据在较大程度上是线性相关,相对误差一般小于１０％,在第２１太阳活动周内,二者符合得极好,第２０太阳活动周内,符合较较好（统计上略微偏小）,第２２太阳尖 相似文献
10.
太阳黑子数月平均变化的长期行为的可预报性 总被引：2，自引：0，他引：2
本用非线性动力系统理论探讨了现代太阳周（１８５０年１月－１９９２年５月）黑子相对数月平均变化过程的可预报性。用时间延迟方法重构吸引子，计算它的最大Ｌｙａｐｕｎｏｖ指数（λ１＝０．０２３±０．００４ ｂｉｔｓ／月），估算了用这些黑子数进行确定性预报的理论时限（ｔ＝３．６±０．６年）。结果表明，动力系统的可预报性与它的最大Ｌｙａｐｕｎｏｖ指数有直接关系，黑子数月平均变化过程的演化不是周期的，也不是拟 相似文献
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In this paper, the expressions of variations of the dynamical ellipticity and the principal moments of inertia due to the
deformations produced by the zonal part of the tidal potential are obtained. Starting from these expressions, we have studied
from equations related to Hamiltonian theory, their effects on the nutation and finally we have evaluated numerically such
influences, with a level of truncation at 0.1 μas. Thus we have shown that some coefficients are quite large with respect
to the usual accuracy of up-to-date observations.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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14.
It is shown that phosphorus availability is in close balance with the phosphorus requirement of the bacterial grain model.
This correspondence, which would be fortuitous if the interstellar grains were of inorganic origin, points to the correctness
of the biological model.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
15.
We have extended our Monte Carlo model of exospheres [Wurz, P., Lammer, H., 2003. Icarus 164 (1), 1-13] by treating the ion-induced sputtering process from a known surface in a self-consistent way. The comparison of the calculated exospheric densities with experimental data, which are mostly upper limits, shows that all of our calculated densities are within the measurement limits. The total calculated exospheric density at the lunar surface of about 1×107 m−3 as result of solar wind sputtering we find is much less than the experimental total exospheric density of about 1012 m−3. We conclude that sputtering contributes only a small fraction of the total exosphere, at least close to the surface. Because of the considerably larger scale height of atoms released via sputtering into the exosphere, sputtered atoms start to dominate the exosphere at altitudes exceeding a few 1000 km, with the exception of some light and abundant species released thermally, e.g. H2, He, CH4, and OH. Furthermore, for more refractory species such as calcium, our model indicates that sputtering may well be the dominant mechanism responsible for the lunar atmospheric inventory, but observational data does not yet allow firm conclusions to be drawn. 相似文献
16.
The area density distribution of bright photospheric points on the quiet solar surface is not uniform. The distributions show some considerable pecularities. This article is a study of their characteristics during the four last solar activity minima in Bartels longitudes. The bright-photospheric-point distributions on the equatorial and polar solar surface exhibit a type of sectoral-hemispherical asymmetry. The density distributions vary a lot, but have the tendency to alternate with a period of 22 years. The phase origin of density concentrations is the first structural pecularity of the photospheric point distributions. The simultaneous appearance of bright regions on the equatorial and polar solar surface in spatial antiphase lock and, at the same time, the half-phase shift (11 years) between polar and equatorial cycles suggests a synchronous distribution process. This time synchronization is the second important pecularity of density concentrations. Therefore, the solar activity organization in minima occurs according to strict synchronization, like being under the control of a very precise clock. 相似文献
17.
M. Melek 《Astrophysics and Space Science》2002,281(4):743-750
A non-conventional approach is developed and used to find the primordial angular gradient, anisotropy, of the temperature
of the Cosmic Microwave Background Radiation (CMBR), as well as the density fluctuations in an adiabatic expanding universe.
The obtained results is a consequence of considering the magnitude of the angular gradient of the temperature of the CMBR
as a constant function with respect to the proper time of the spatially perturbed FRW expanding universe.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
18.
Rodney S. Gomes Tabaré Gallardo Julio A. Fernández Adrián Brunini 《Celestial Mechanics and Dynamical Astronomy》2005,91(1-2):109-129
We study the transfer process from the scattered disk (SD) to the high-perihelion scattered disk (HPSD) (defined as the population
with perihelion distances q > 40 AU and semimajor axes a>50 AU) by means of two different models. One model (Model 1) assumes
that SD objects (SDOs) were formed closer to the Sun and driven outwards by resonant coupling with the accreting Neptune during
the stage of outward migration (Gomes 2003b, Earth, Moon, Planets 92, 29–42.). The other model (Model 2) considers the observed population of SDOs plus clones that try to compensate for observational
discovery bias (Fernández et al. 2004, Icarus , in press). We find that the Kozai mechanism (coupling between the argument of perihelion, eccentricity, and inclination),
associated with a mean motion resonance (MMR), is the main responsible for raising both the perihelion distance and the inclination
of SDOs. The highest perihelion distance for a body of our samples was found to be q = 69.2 AU. This shows that bodies can
be temporarily detached from the planetary region by dynamical interactions with the planets. This phenomenon is temporary
since the same coupling of Kozai with a MMR will at some point bring the bodies back to states of lower-q values. However,
the dynamical time scale in high-q states may be very long, up to several Gyr. For Model 1, about 10% of the bodies driven
away by Neptune get trapped into the HPSD when the resonant coupling Kozai-MMR is disrupted by Neptune’s migration. Therefore,
Model 1 also supplies a fossil HPSD, whose bodies remain in non-resonant orbits and thus stable for the age of the solar system,
in addition to the HPSD formed by temporary captures of SDOs after the giant planets reached their current orbits. We find
that about 12 – 15% of the surviving bodies of our samples are incorporated into the HPSD after about 4 – 5 Gyr, and that
a large fraction of the captures occur for up to the 1:8 MMR (a ⋍ 120 AU), although we record captures up to the 1:24 MMR
(a ≃ 260 AU). Because of the Kozai mechanism, HPSD objects have on average inclinations about 25°–50°, which are higher than
those of the classical Edgeworth–Kuiper (EK) belt or the SD. Our results suggest that Sedna belongs to a dynamically distinct
population from the HPSD, possibly being a member of the inner core of the Oort cloud. As regards to 2000 CR105 , it is marginally within the region occupied by HPSD objects in the parametric planes (q,a) and (a,i), so it is not ruled
out that it might be a member of the HPSD, though it might as well belong to the inner core. 相似文献
19.
A. Akhperjanian R. Kankanian V. Sahakian A. Heusler C.-A. Wiedner H. Wirth 《Experimental Astronomy》1998,8(2):135-152
The raytracing technique was used to derive a suitable design for the HEGRA system of Cherenkov telescopes, which is at present commissioned at La Palma. The reflectors with a diameter of 3.9 m consist of 30 spherical mirrors with focal lengths in the range of 4.88 – 4.94 m. It is shown that 93% of the photons from the Cherenkov light emitted by an extended air shower are contained in the camera pixels, 0.25° in diameter, for the full field of view of = ± 2.5°. The optical performance of the HEGRA design is compared to other layouts. 相似文献
20.