The morphology and velocity field of the large flare on the solar disc on July 14, 1980

The active region morphology and the features of solar radio bursts and sight-line velocity distribution of a flare of Importance 3B on the solar disc (AR 2562) on 1980 July 14 are introduced in this article.     

The flares of April, 1980

A brief report is given on the characteristics of solar flares from the active region Boulder 2372. It is interesting to note the morphological similarity (homology) between many of these events, most likely caused by the overall constancy of the magnetic field configuration. Under closer examination this first-order homology breaks down, a fact that may help us understand the basis of the flare mechanism.     

Coronal mass ejection detection using wavelets,curvelets and ridgelets: Applications for space weather monitoring

Coronal mass ejections (CMEs) are large-scale eruptions of plasma and magnetic field that can produce adverse space weather at Earth and other locations in the Heliosphere. Due to the intrinsic multiscale nature of features in coronagraph images, wavelet and multiscale image processing techniques are well suited to enhancing the visibility of CMEs and suppressing noise. However, wavelets are better suited to identifying point-like features, such as noise or background stars, than to enhancing the visibility of the curved form of a typical CME front. Higher order multiscale techniques, such as ridgelets and curvelets, were therefore explored to characterise the morphology (width, curvature) and kinematics (position, velocity, acceleration) of CMEs. Curvelets in particular were found to be well suited to characterising CME properties in a self-consistent manner. Curvelets are thus likely to be of benefit to autonomous monitoring of CME properties for space weather applications.     

The effect of total solar eclipse of October 3, 2005, on the total electron content over Europe

GPS observations from EUREF permanent GPS network were used to observe the response of TEC (Total Electron Content) to the total solar eclipse on October 3, 2005, under quiet geomagnetic conditions of the daytime ionosphere. The effect of the eclipse was detected in diurnal variations and more distinctly in the variations of TEC along individual satellite passes. The trough-like variations with a gradual decrease and followed by an increase of TEC at the time of the eclipse were observed over a large region. The depression of TEC amounted to 3–4 TECU. The maximum depression was observed over all stations located at the maximum path of the solar eclipse. The delay of a minimum level of TEC with respect to the maximum phase of the eclipse was about 20–30 min.     

A homologous microwave flare on May 29, 1980

Two homologous solar bursts were recorded on May 29, 1980 at 1028 UT and at 1147 UT from the Hale region 16864. The measurements were done at 8 mm wavelength at the Metsähovi Radio Research Station using a 14 meter radio telescope. The time series of the bursts were similar even in the small details. The rise time of both bursts was about 10 seconds and the peak flux density was 3.3 sfu at 1028 UT and 1.2 sfu at 1147 UT. Both bursts were composed of several elementary spikes which were typically 3 seconds apart from each other. The maximum of the gyro-synchrotron type spectrum was close to 15 GHz. The time profile of the bursts, elementary spikes and the frequency spectrum indicated that the origin of these homologous microwave bursts was in a magnetic structure with several loops and that the same complex loop structure was producing energy during both bursts.     

The GPS measured SITEC caused by the very intense solar flare on July 14, 2000

This work studies the sudden increases in total electron content of the ionosphere caused by the very intense solar flare on July 14, 2000. Total electron content (TEC) data observed from a Global Positioning System (GPS) network are used to calculate the flare-induced TEC increment, δTEC_f, and variation rate, dTEC_f/dt. It is found that both dTEC_f/dt and δTEC_f are closely related with the solar zenith angles. To explain the observation results, we derived a simple relationship between the partial derivative of the flare-induced TEC, ∂TEC_f/∂t, which is a good approximation for dTEC_f/dt, and the solar zenith angle χ, as well as the effective flare radiation flux I_f, according to the well-known Chapman theory of ionization. The derived formula predicted that ∂TEC_f/∂t is proportional to I_f and inverse proportional to Chapman function ch(χ). This theoretical prediction not only explains the correlation of dTEC_f/dt and δTEC_f with χ as shown in our TEC observation, but also gives a way to deduce I_f from TEC observation of GPS network. Thus, the present work shows that GPS observation is a powerful tool in the observation and investigation of solar flare effects on the ionosphere, i.e., the sudden ionospheric disturbances, which is a significant phenomenon of space weather.     

The 1980 April 12 flare and transient: Report on progress in interpretation

A multidisciplinary study of this solar-interplanetary event is summarized by two main points: this flare was an incident in a process that began days before the flare, and continued after the flare; and the chain of events can be interpreted most simply in terms of energy input over scales of time and space that are large compared to the flare seen in the light of Hα. In support of these points, 5 aspects of the flare are described here: (1) hours before the flare, slow changes in coronal structure were associated with radio continuum emission, suggesting large-scale magnetic-field changes and the presence of energetic electrons; (2) long-lived X-ray loops require sustained energy input for at least an hour after the flare start; (3) interplanetary disturbance near earth is probably related to this limb flare, although the (expected) absence of a shock makes identification uncertain; (4) the coronal mass ejection overlay decaying magnetic field; (5) speed derived from frequency drift of the type II radio burst in the low corona, and from the travel time of the disturbance to 1 a.u., are about twice as great as the observed speed of the coronal mass ejection and of the disturbed solar-wind speed.     

VHF radio response of the near Earth space during solar activity growth in October, 2003

The analysis of observations of very high frequency radio noise intensity at the middle latitude on a frequency f = 500 MHz from 14th till 26th of October, 2003 is presented. These data are compared with the solar radio bursts in the range of frequencies 1–14 MHz registered by RAD2 receiver of the WAVES device installed on board the WIND spacecraft.     

The ion energy and mass analyzer on board the ‘Intercosmos-Bulgaria-1300’ satellite

An original instrument for ion energy distribution measurement in ionospheric plasma above the F-layer was designed and launched on board the ‘INTERCOSMOS-BULGARIA-1300’ satellite. The instrument performs differential energy analysis of ion species within the two energy ranges of 1 – 27 eV/q and 0.2–8keV/q.     

The dose rate observed on 19-21 October 1989 and its modulation by geophysical effects.

The Liulin dosimeter-radiometer on the MIR space station detected the 19 October 1989 high energy solar proton event. These results show that the main particle increase contains protons with energies up to about 9 GeV. After the main particle onset the Liulin dosimeter observed a typical geomagnetic cutoff modulation of the dose rate from the solar particles as the MIR space station traversed magnetic latitudes. When the interplanetary shock and associated solar plasma enveloped the earth on 20 October between 14 and 17 UT the radiation exposure increased significantly due to the lowering of the geomagnetic cutoff. The analysis of this event shows how various geophysical phenomena can significantly modulate the dose rate encountered by earth-orbiting spacecraft.     

Report on COSPAR/SCOR/IUCRM symposium—oceanography from Space,Venice, Italy, 26–30 May 1980

A brief summary is given of the results of oral and poster sessions and informal discussions in the various topics in “Oceanography from Space” discussed at the Venice meeting.     

The relation between the Black hole mass and the Bulge mass for low redshift AGNs. Part I: Ground-based observations

Using the bulge data from AGN image decomposition with ground-based observations, we calculate the ratios of the central supermassive black hole mass(SMBH) to the Bulge mass (_Mbh/_Mbulge$M_{\text{bh}}/M_{\text{bulge}}$) in a sample of X-ray selected AGNs, including 15 Narrow-line Seyfert 1 galaxies (NLS1s) and 18 broad-line Seyfert 1 galaxies (BLS1s). We found that the mean value of log(_Mbh/_Mbulge)$\log (M_{\text{bh}}/M_{\text{bulge}})$ is -3.81±0.11$-3.81\pm 0.11$ for 15 NLS1s, and -2.91±0.13$-2.91\pm 0.13$ for 18 BLS1s, showing the lower _Mbh/_Mbulge$M_{\text{bh}}/M_{\text{bulge}}$ in NLS1s relative to BLS1s. The calculation shows that the Bulge mass from the host image decomposition in NLS1s is statistically smaller than that from Hubble-type correction method, and a linear mass relation is suggested for NLS1s and a nonlinear mass relation for BLS1s. The studying of host galaxies with ground-based observations strongly limited by the atmospheric seeing. We need to do the decomposition of host images for NLS1s with Hubble Space Telescope observation in the future.     

On the association of eruptive prominences, coronal holes and current sheets with the coronal mass ejections

In this paper, a study of the coronal mass ejections (CMEs) observed by Solar Maximum Mission satellite (SMM) during the period March – September, 1980, is presented. An attempt to identify various possible associations of the solar phenomena, for example, the location of coronal holes, the role of eruptive filaments or prominences, and current-sheets with the CMEs is carried out. It is shown that the combined associations of these three play an important role in the occurrence of geoeffective CMEs and also act as a tool to predict the associated geomagnetic activity.     

The giant planets and their satellites: Report on the Cospar Symposium,Ottawa, Canada,May 18–21, 1982

A $\text{Symposium on the Giant Planets and Their Satellites}$ was presented in conjunction with the Twenty-fourth Plenary Meeting of the Committee on Space Research. This paper summarizes the talks presented and places the remaining papers of this volume in context.     

同样的距离,不一样的旅程

嫦娥二号与嫦娥一号这对姐妹的奔月旅程有什么不同呢?这对姐妹的旅程可概括为一句话--同样的距离,不一样的旅程.     

Climatology of the quasi two-day wave over Saskatoon (52°N, 107°W): 14 Years of MF radar observations

Oscillations in the wind field due to the “quasi two-day” wave (Q2DW) have been studied using 14 years of Medium Frequency (MF) radar data over Saskatoon (52°N). The results of analyses have shown that the Q2DW exhibits complex seasonal variability: in addition to the well-known strong summer activity the wave also has been found in winter months. In summer the amplitudes of the Q2DW in meridional (NS) and zonal (EW) winds have comparable values, while they tend to be larger in EW winds in winter. The heights of the maximum amplitude are lower in winter than in summer and there are indications of changes in the dominant period of oscillations throughout the year.     

The chemical conditions on the parent body of the murchison meteorite: Some conclusions based on amino, hydroxy and dicarboxylic acids

Amino and hydroxy acids have been identified in the Murchison meteorite. Their presence is consistent with a synthetic pathway involving aldehydes, hydrogen cyanide and ammonia in an aqueous environment (Strecker-cyanohydrin synthesis). From the various equilibrium and rate constants involved in this synthesis, four independent estimates of the ammonium ion concentrations on the parent body at the time of compound synthesis are obtained; all values are about 2 × 10^?3 M. Succinic acid and β-alanine have also been detected in the Murchison meteorite. Their presence is consistent with a synthesis from acrylonitrile, hydrogen cyanide and ammonia. Using the equilibrium and rate constants for this synthetic pathway, and the succinic acid/β-alanine ratio measured in the Murchison meteorite, an estimate of the hydrogen cyanide concentration of 10^?3 to 10^?2 M is obtained. Since hydrogen cyanide hydrolyzes relatively rapidly in an aqueous environment ($\text{t}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{< 10}{}^4\text{yrs}$) this high concentration implies a period of synthesis of organic compounds as short as 10⁴ years on the Murchison meteorite parent body.     

The generator system of field-aligned currents during the April 06, 2000, superstorm

Using ground-based magnetometer data of the April 6–7, 2000, superstorm, we obtained maps of ionospheric and field-aligned currents (FACs). Based on these, we deduced the electrical circuit of the disturbed magnetosphere/ionosphere and a conceptual model of its magnetospheric generators, which supply both hemispheres. This model implies that the generator system creates primarily the Region-1 FACs of Iijima and Potemra at both hemispheres, while the Region-2 and Region-0 FACs form by spreading of the Region-1 currents through the ionosphere. This conclusion is supported by observations.