Planetary-induced sunspots inferred from WDC-Silso data.

Sunspots observation and classification are important tasks for solar astronomers. The activity of sunspots can give clues to the timing of solar flares and the solar weather in general. This paper describes a hybrid system for automatic sunspot recognition and classification. The system uses a combination of image processing and machine learning techniques to process and classify sunspot groups from digital satellite images. Sunspot data are extracted from daily images of the solar disk captured by the NASA SOHO/MDI satellite. The classification scheme attempted was the seven-class Modified Zurich scheme. The main components of the hybrid system are: 1) the image processor, 2) the feature extractor, 3) the clusterer, 4) the classification learner. Furthermore, the paper compares two clustering algorithms: hierarchical average-link and a density-based DBSCAN and examines their usefulness in dealing with sunspot data. The aim is to create clusters that closely match natural sunspot groups. Clustering is an important step in the process as the classification performance is dependent on it. In previous papers we have shown that by combining clustering with classification the overall results can be substantially improved.

Venus is Earth’s closest planetary neighbour and both bodies are of similar size and mass. As a consequence, Venus is often described as Earth’s sister planet. But the two worlds have followed very different evolutionary paths, with Earth having benign surface conditions, whereas Venus has a surface temperature of 464 °C and a surface pressure of 92 bar. These inhospitable surface conditions may partially explain why there has been such a dearth of space missions to Venus in recent years.The oxygen isotope composition of Venus is currently unknown. However, this single measurement (Delta ^{17}text{O}) would have first order implications for our understanding of how large terrestrial planets are built. Recent isotopic studies indicate that the Solar System is bimodal in composition, divided into a carbonaceous chondrite (CC) group and a non-carbonaceous (NC) group. The CC group probably originated in the outer Solar System and the NC group in the inner Solar System. Venus comprises 41% by mass of the inner Solar System compared to 50% for Earth and only 5% for Mars. Models for building large terrestrial planets, such as Earth and Venus, would be significantly improved by a determination of the Delta ^{17}text{O} composition of a returned sample from Venus. This measurement would help constrain the extent of early inner Solar System isotopic homogenisation and help to identify whether the feeding zones of the terrestrial planets were narrow or wide.Determining the Delta ^{17}text{O} composition of Venus would also have significant implications for our understanding of how the Moon formed. Recent lunar formation models invoke a high energy impact between the proto-Earth and an inner Solar System-derived impactor body, Theia. The close isotopic similarity between the Earth and Moon is explained by these models as being a consequence of high-temperature, post-impact mixing. However, if Earth and Venus proved to be isotopic clones with respect to Delta ^{17}text{O}, this would favour the classic, lower energy, giant impact scenario.We review the surface geology of Venus with the aim of identifying potential terrains that could be targeted by a robotic sample return mission. While the potentially ancient tessera terrains would be of great scientific interest, the need to minimise the influence of venusian weathering favours the sampling of young basaltic plains. In terms of a nominal sample mass, 10 g would be sufficient to undertake a full range of geochemical, isotopic and dating studies. However, it is important that additional material is collected as a legacy sample. As a consequence, a returned sample mass of at least 100 g should be recovered.Two scenarios for robotic sample return missions from Venus are presented, based on previous mission proposals. The most cost effective approach involves a “Grab and Go” strategy, either using a lander and separate orbiter, or possibly just a stand-alone lander. Sample return could also be achieved as part of a more ambitious, extended mission to study the venusian atmosphere. In both scenarios it is critical to obtain a surface atmospheric sample to define the extent of atmosphere-lithosphere oxygen isotopic disequilibrium. Surface sampling would be carried out by multiple techniques (drill, scoop, “vacuum-cleaner” device) to ensure success. Surface operations would take no longer than one hour.Analysis of returned samples would provide a firm basis for assessing similarities and differences between the evolution of Venus, Earth, Mars and smaller bodies such as Vesta. The Solar System provides an important case study in how two almost identical bodies, Earth and Venus, could have had such a divergent evolution. Finally, Venus, with its runaway greenhouse atmosphere, may provide data relevant to the understanding of similar less extreme processes on Earth. Venus is Earth’s planetary twin and deserves to be better studied and understood. In a wider context, analysis of returned samples from Venus would provide data relevant to the study of exoplanetary systems.

During the past quarter century, manned and unmanned spacecraft have explored seven planets, nearly three dozen moons, and one comet. In the process, astronomical objects have been transformed into unique worlds exhibiting a diversity of geological processes and materials. A new science of comparative planetology has developed, in which field experience on the Earth and the Moon aid in interpreting less well-known worlds. The processes that must have operated on the early Earth have been deduced from evidence from ancient surfaces of the Moon and planets. In particular, such comparative studies have demonstrated that only two geologic processes have been widespread throughout the history of the solar system: impact cratering and volcanism. Impact craters have formed throu hout solar system history, indeed the planets themselves were formed by the accumulation of millions of smaller planetesimals, each of which formed an impact crater. Earth could not have escaped the intense bombardment that churned the surfaces of Mars, Mercury, and the Moon. The impact cratering rate dramatically declined about 3.9 billion years ago, but craters 10 km across still form on the Earth on the average of one every 140,000 years, and the 1.5-km wide Meteor Crater in Arizona formed only about 25,000 years ago. Volcanic flows and cones have been observed on nearly all planets and moons in the solar system; the variety and duration of volcanism are directly related to planet mass. Thus, a relatively large planet like the Earth has a wide range of volcanic morphologies and compositions, with activity continuing throughout Earth history. In contrast, the smaller Moon produced a narrow compositional range of basaltic lava flows, with most of the lavas having erupted about 3 billion years ago. Water and sulfur volcanism have also been discovered on the cold satellites of the outer solar system, thus expanding our terrestrial concept of volcanism. Many other processes and materials exist in the solar system, but the Earth remains unique in its richness of resources to support humans. Discovery and exploitation of extraterrestrial resources are beginning and must be greatly increased to prepare for our future as a space-faring race. End_of_Article - Last_Page 1443------------

We analyze the temporal distribution of sunspot groups for even and odd cycles in the range SC12-SC24. It seems that cycle 24 is a characteristic even cycle, although with low amplitude. The number of large sunspot groups for cycle 24 is relatively smaller than for the average of both even and odd cycles SC12-SC23, and there is a deep decline of the large groups in the middle of the cycle. Temporal evolution of the sunspot groups of the even cycles is non-synchronous such that the northern hemisphere distribution of groups maximizes earlier that the southern hemisphere groups. This leads to a double-peak structure for the average even cycle. On the other hand, the distributions of the sunspot groups of odd cycles maximize simultaneously. We show that this double-peak structure intensifies the Gnevyshev gap (GG) for the even cycles, but is not its primary cause. On the contrary, we show that the GG exists for even and odd cycles, and separately on both hemispheres. We resample all cycles to have equal number of 3945 days and study the difference in the evolution of average total group area and average group area of the even and odd cycles separately. The analysis shows that there is a decline in both total area and average area in the even cycles 1445 days (about four years) after the beginning of the cycle, which is at least 99 % significant for both total and average area. The odd cycles do not have such a clear decline.

The nearly circular (mean eccentricity [Formula: see text]) and coplanar (mean mutual inclination [Formula: see text]) orbits of the solar system planets motivated Kant and Laplace to hypothesize that planets are formed in disks, which has developed into the widely accepted theory of planet formation. The first several hundred extrasolar planets (mostly Jovian) discovered using the radial velocity (RV) technique are commonly on eccentric orbits ([Formula: see text]). This raises a fundamental question: Are the solar system and its formation special? The Kepler mission has found thousands of transiting planets dominated by sub-Neptunes, but most of their orbital eccentricities remain unknown. By using the precise spectroscopic host star parameters from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) observations, we measure the eccentricity distributions for a large (698) and homogeneous Kepler planet sample with transit duration statistics. Nearly half of the planets are in systems with single transiting planets (singles), whereas the other half are multiple transiting planets (multiples). We find an eccentricity dichotomy: on average, Kepler singles are on eccentric orbits with [Formula: see text] 0.3, whereas the multiples are on nearly circular [Formula: see text] and coplanar [Formula: see text] degree) orbits similar to those of the solar system planets. Our results are consistent with previous studies of smaller samples and individual systems. We also show that Kepler multiples and solar system objects follow a common relation [[Formula: see text](1-2)[Formula: see text]] between mean eccentricities and mutual inclinations. The prevalence of circular orbits and the common relation may imply that the solar system is not so atypical in the galaxy after all.

Jupiter expedition .sc ientists Tull, Van Citters, Nather, Evans and Wells. Astronomers have studied the solar system for centuries, but they still cannot agree on how the planets originated. Many theorists assume that the planets were formed from material thrown off by the sun, either as a result of a near collision with some other star or by another means, but even those who agree on this cannot agree on whether the planets were ever hot bodies or whether they were formed by cold accretion and were never much warmer than they are now. Jupiter is the largest planet of the solar system, and it has been suggested that it may not be made of solar material at all. Some astronomers believe that Jupiter is a dead, or almost dead. star that the sun has captured into orbit. Such a situation would be by no means unique in the universe. In our Milky Way galaxy there are many examples of binary or multiple stars, in which two or more stars are bound together by gravitational forces and revolve around each other. In many of these cases bright stars have dark, cold companions. In Jupiter's case the planet's composition tends to support the idea that it may be a star. Hydrogen and helium are the two most prominent constituents of the planet's mass. These elements are abundant in stars, but they are almost lacking in the terrestrial planets, Mercury, Venus, earth and Mars, which are almost certainly not originally stars. The other large planets, however, Saturn, Uranus and Neptune, have compositions that are in many ways similar to Jupiter's, and they may share a common origin with it. Jupiter's radiation also tends to support the notion of independent stellar origin. The light received from planets is reflected sunlight, but Jupiter's radio emission shows the planet to be a few degrees hotter than heating by the sun can account for. This circumstance ,as led some astronomers to suggest that in the center of Jupiter, under layers of frozen hydrogen and helium, is the dying remnant of a stellar core that is still producing a little surplus energy. Those who would argue that Jupiter is a planet made from accretion of material thrown off by the sun point out that the elements hydrogen and helium are abundant in the sun and would be abundant in any cloud expelled by it. They are abundant in the larger planets, this argument goes, because the outer planets are large enough to have the gravity to retain them. The terrestrial planets, whose main constituents are the heavier elements iron and silicon, were too small to retain the light gases. Nobody explains why the terrestrial planets are small and the outer planets large. Pluto, the farthest planet, re-

Jupiter is the largest planet in the solar system and the fifth planet from the sun. In 1955, the Jupiter's signal had been noticed by radio lasers near Jupiter's magnetic poles. Since that, the Jupiter's activities had been studied and observed by the astronomer until now. The frequencies of Jupiter's most intense radio emissions extend from around 50 kHz up to 40 MHz. However, the observers usually listened on 20.1 Mhz because it is well above the ionospheres cut-off frequency and it is not where man made transmission frequencies would interfere. These emissions usually received with an amateur radio telescope. The Malaysia Space Agency had proposed the Radio Jupiter project to explore more about Jupiter's activities such as noise storms, flares, geomagnetic activity prediction and other scientific activities. The Radio Jupiter consist of three main components; antenna, receiver and amplifier, and recorder. This paper describes an overview of Radio Jupiter Project design and focus on designing a recorder which is a pc based software that uses as a little external hardware to record the Jupiter's signal. Finally, the data output from the system is presented and discussed.

More than ten times the Earth in diameter and 300 times as massive, Jupiter is by far the largest planet in the Solar System. Fifth in order of distance from the Sun, which it orbits in 11.8626 years, Jupiter spins more rapidly than any other planet, with a rotation period of just under 10 hours. Unlike the Earth and the other ‘terrestrial’ planets, Jupiter's principal chemical constituent is hydrogen, mainly in the molecular gaseous form at the visible cloud levels in the Jovian atmosphere, but liquid at the high pressures prevailing at much deeper levels within the planet. The electrical conductivity increases from negligible values near the cloud levels to metallic values at great depth. Differential rotation between equatorial and higher-latitude regions of the Jovian atmosphere is reflected in the two systems of zenographic longitude introduced by observers monitoring the motions of atmospheric cloud patterns. These are Systems I and II with rotation periods T 1 =35430.003s (9h 50min 30.003s) and T 2 =35740.632s (9h 55min 40.632s) respectively. The most striking feature of the cloud patterns is the durable (but longitudinally mobile) Great Red Spot, originally known as ’Hooke's Spot’, the first observations of which were recorded in the Philosophical Transactions of The Royal Society of London at the very beginning of its first issue, published in 1665. Differential rotation between the atmosphere and underlying electrically conducting regions is reflected in the need for radio astronomers to use yet another zenographic longitude system—System III, with rotation period T 3 =35729.771s (9h 55min 29.711s)––when monitoring powerful Jovian sources of non-thermal electromagnetic radiation at decimeter and decametre wavelengths. These are located in the plasma envelope of Jupiter, which is closely tied to the deep interior of the planet by lines of force of the zenomagnetic field.

ABSTRACTNumerous analyses suggest the existence of various quasi-periodicities in solar activity. The power spectrum of solar activity recorded in sunspot data is dominated by the ∼11-yr quasi-periodicity, known as the Schwabe cycle. In the mid-term range (1 month–11 yr) a pronounced variability known as a quasi-biennial oscillation is widely discussed. In the shorter time-scale a pronounced peak, corresponding to the synodic solar rotation period (∼27 d), is observed. Here we revisit the mid-term solar variability in terms of statistical dynamics of fully turbulent systems, where solid arguments are required to accept an isolated dominant frequency in a continuous (smooth) spectrum. For this, we first undertook an unbiased analysis of the standard solar data, sunspot numbers and the F10.7 solar radio flux index, by applying a wavelet tool, which allows one to perform a frequency–time analysis of the signal. Considering the spectral dynamics of solar activity cycle by cycle, we showed that no single periodicity can be separated, in a statistically significant manner, in the specified range of periods. We examine whether a model of the solar dynamo can reproduce the mid-term oscillation pattern observed in solar data. We found that a realistically observed spectrum can be explained if small spatial (but not temporal) scales are effectively smoothed. This result is important because solar activity is a global feature, although monitored via small-scale tracers like sunspots.

Asteroids and other Small Solar System Bodies (SSSBs) are of high general and scientific interest in many aspects. The origin, formation, and evolution of our Solar System (and other planetary systems) can be better understood by analysing the constitution and physical properties of small bodies in the Solar System. Currently, two space missions (Hayabusa2, OSIRIS-REx) have recently arrived at their respective targets and will bring a sample of the asteroids back to Earth. Other small body missions have also been selected by, or proposed to, space agencies. The threat posed to our planet by near-Earth objects (NEOs) is also considered at the international level, and this has prompted dedicated research on possible mitigation techniques. The DART mission, for example, will test the kinetic impact technique. Even ideas for industrial exploitation have risen during the last years. Lastly, the origin of water and life on Earth appears to be connected to asteroids. Hence, future space mission projects will undoubtedly target some asteroids or other SSSBs. In all these cases and research topics, specific knowledge of the structure and mechanical behaviour of the surface as well as the bulk of those celestial bodies is crucial. In contrast to large telluric planets and dwarf planets, a large proportion of such small bodies is believed to consist of gravitational aggregates ('rubble piles') with no -- or low -- internal cohesion, with varying macro-porosity and surface properties (from smooth regolith covered terrain, to very rough collection of boulders), and varying topography (craters, depressions, ridges) [...].

The long-term modulation of cosmic ray intensity (CRI) by different solar activity (SA) parameters and an inverse correlation between individual SA parameter and CRI is well known. Earlier, it has been suggested that the concept of multi-parametric modulation of CRI may play an important role in the study of long-term modulation of CRI. In the present study, we have tried to investigate the combined effect of a set of two SA parameters in the long-term modulation of CRI. For this purpose, we have used a new statistical technique called “Running multiple correlation method”, based on the “Running cross correlation method”. The running multiple correlation functions among different sets of two SA parameters (e.g., sunspot numbers and solar flux, sunspot numbers and coronal index, sunspot numbers and grouped solar flares, etc.) and CRI have been correlated separately. It is found that the strength of multiple correlation (among two SA parameters and CRI) and cross correlation (between individual SA parameter and CRI) is almost similar throughout the period of investigation (1955–2005). It is also found that the multiple correlations among various SA parameters and CRI is stronger during ascending and descending phases of the solar cycles and it becomes weaker during maxima and minima of the solar cycles, which is in accordance with the linear relationship between SA parameters and CRI. The values of multiple correlation functions among different sets of SA parameters and CRI fall well within the 95% confidence interval. In the view of odd-even hypothesis of solar cycles, the strange behaviour of present cycle 23 (odd cycle), as this is characterized by many peculiarities with double peaks and many quiet periods (Gnevyshev gaps) interrupted the solar activity (for example April 2001, October–November 2003 and January 2005), leads us to speculate that the solar cycle 24 (even cycle) might be of exceptional nature.

Correlation between the sunspot number and tropospheric refractivity in a tropical environment

Wacker family takes control of Wacker Chemie

Ultrasonic depolymerization at elevated static presusre : Sergeeva, K.Y. Soviet Physics Acoustics, 13, No 1, p 120 (July–September 1967)

The Sun provides most of external energy to Earth’s system and thus has the potential of influencing it. Various studies reported a correlation between the solar cycle length and the northern hemisphere temperatures on Earth. Here, we reassess the cycle length record by incorporating the newly revised and updated sunspot number series as well as plage area composite, before comparing it to Earth temperature records. We find that cycle length series constructed from sunspot and plage data exhibit the same behaviour, both showing a downward trend after 1940. Our results suggest that the agreement between solar cycle lengths and temperatures found earlier is an artefact of (1) some arbitrary choices made by those studies when constructing the cycle length series as well as (2) a rather short time interval, to which the analyses were restricted. When considering the entire period of reliable sunspot and temperature data, these records diverge before about 1870 and after 1960. We also find a poor agreement between Earth temperatures and cycle length when using plage areas instead of sunspot data to derive cycle lengths. Our result of the divergence between cycle length series and Earth’s temperature after 1960 implies that the cycle length cannot be used to support a solar origin for the warming on Earth over the last 5 decades.