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1.
Solar limb brightening measurements at a wavelength of 3.3 mm were made during the 30 June 1973 total solar eclipse from a site at Lake Rudolf, Kenya. The results show that at this wavelength there is a limb brightening of about 20%, occurring within one half arc min of the limb. 相似文献
2.
John P. Hagen Paul N. Swanson Robert W. Haas Fred L. Wefer Raymond W. Vogt 《Solar physics》1971,21(2):286-296
The 7 March, 1970 total solar eclipse was observed at wavelengths of 3.2 and 8.3 mm; the object being to use the knife edge of the Moon as it passed across the Sun to improve angular resolution on the Sun. This in turn would provide a radial brightness distribution of the Sun with an angular resolution of a few seconds of arc.Excellent eclipse curves were obtained at 3 mm; however, some external interference marred the 8 mm record near totality.The 8 mm brightness distribution is subject to some uncertainty, but tends to show limb brightening. The 3 mm brightness distribution shows a well defined complex limb brightening within about 1 arc min of the optical limb. The maximum brightening is approximately 30% above the average disc temperature. 相似文献
3.
Observations at 9 mm wavelength of the partial solar eclipse of February 25th 1971 were made to investigate possible limb brightening of the Sun. The results obtained show that less than 5% of the solar disc power can be contained in any such brightening. 相似文献
4.
G. Chimonas 《Planetary and Space Science》1973,21(11):1843-1854
The Lamb waves excited by an eclipse induced cooling of a cloud bearing tropospheric region are invoked to explain an experimental result obtained in the 7 March 1970 solar eclipse. Quantitative investigations are severely handicapped by the lack of data concerning the cooling rates throughout the region, but show that if this cooling rate is of the order of magnitude of the ‘lost’ insolation the Lamb waves will explain the observed ground level pressure fluctuations. 相似文献
5.
《Chinese Astronomy and Astrophysics》1999,23(2):237-243
COPY THE ORIGINAL Analysis of the total eclipse observation of 1997 March 9 at wavelength 8.6 mm, shows that, at this wavelength, the solar radius is 1.012 R⊙, the total flux density is 2540 sfu, the mean brightness temperature of the solar disk is 9632 K, and the brightness temperature distribution shows limb brightening at the inner edge of the solar disk, the average brightness at 0.936−0.992 R⊙ being 9.7% above the central brightness. 相似文献
6.
Rocket measurements of the solar L (1216 Å) flux during various phases of the total eclipse of 12 November, 1966 confirm that the radiation emanates from the chromosphere. A significant difference between two portions of the photosphere limb is attributed to enhanced emission in the region of a Ca K plage. The average size of the L disk is found to be approximately 4000 km above the photosphere, and a brightening is observed at the limb. 相似文献
7.
A detailed photometric analysis has been made of a narrow elongated coronal streamer observed at the 1973 total eclipse. After deriving real intensity distributions, the electron density has been deduced under the assumption that the distribution is axially symmetric and that the decrease in density from the central axis follows the gaussian law. The results show that the gradient of the electron density is much steeper at the lower part, nearest to the solar limb, than those reported previously for larger scale streamers.On leave from the Observatorio de Huancayo, Instituto Geoflsico del Peru as a trainee of the Japan International Cooperation Agency. 相似文献
8.
VLAD Popa 《Astrophysics and Space Science》2002,282(1):235-244
During the 1999 total solar eclipse we intended to search for photons emitted by a possible radiative decay of the heavier
component of solar neutrinos, using two telescopes: an airborne one, and another at mountain altitude, in Romania(the NOTTE
experiment). The weather conditions did not allow us to perform the measurements. Alternatively, we analyzed a video tape
of the eclipse offered to us by a local television, obtaining some qualitative estimations on the neutrino lifetimes. We present
also a first report on the observations made 21 June 2001, from Zambia.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
Shape and structure of the solar corona during the August 1, 2008, total solar eclipse is reported. The August 1, 2008, corona
is classified as of near-minimum type with well developed northern and southern polar ray systems over polar coronal holes
and several streamers of different brightness at the middle and low heliographic latitude. The flattening index was found
to be 0.21. 相似文献
10.
We report accurate timing of second and third contacts made from videotape of the total solar eclipse of 23 November, 1984, observed in Papua New Guinea. The magnitude of the discrepancies between predicted and observed times indicates that the secular change in the size of the Sun reported by some observers is within the uncertainty. 相似文献
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13.
We present digitized photographs of the white-light solar corona taken during the total solar eclipse of 22–23 November, 1984, on both calibrated black-and-white film and on color film. Conditions on site in Hula, Papua New Guinea, were exceptionally clear. The color image was used to produce an isophotal map of the inner corona, from which a flattening coefficient of 0.23 was measured. The black-and-white image was enhanced through a digital radial filter. Our images are the best processed images available from the 1984 eclipse and so provide important data for synoptic observations. 相似文献
14.
《Astroparticle Physics》2010,33(6):286-293
In the past, there have been reports of the observation of decrease in the flux of secondary cosmic γ-rays during a total solar eclipse. We have measured the flux of secondary cosmic γ-rays during the total solar eclipse that occurred at Novosibirsk in Russia, on 1 August 2008. Highly sensitive measurements were carried out by using a detector system with built-in redundancy. The system consisted of two independent, large volume NaI(Tl) scintillator detectors for sensitive and reliable measurements. The data display significant variability in the flux of secondary γ-rays in the energy range 50–4600 keV. Just prior to the total solar eclipse a change ∼9% in the flux was observed, followed by a small but steady decrease ∼4% during the eclipse. The temporal variation in the observed flux of γ-rays were found to be nearly identical for the two detectors. The energy dependence of the variation was further studied by binning the yield in three energy ranges, namely, 100–200, 200–400 and 400–4600 keV. The nearly identical time variation observed in the two independent measurements provides confidence that the measured variation is real and not an artifact of the instrumentation. Systematic observations during the future eclipses are required to study this fascinating phenomenon which is not yet understood. 相似文献
15.
Observations of coronal Fe XIV emission lines from the NE quadrant during the 1973 solar eclipse are reported. Temperatures are deduced from a pure thermal broadening model, and, in the region near an observed white-light enhancement, an alternative interpretation of halfwidth as being in part due to turbulent velocities is suggested.On leave from the Los Alamos National Laboratory 1981 - present. 相似文献
16.
Cowsik Ramanath Singh Jagdev Saxena A.K. Srinivasan R. Raveendran A.V. 《Solar physics》1999,188(1):89-98
Encouraged by the detection of high-frequency, low-amplitude continuum intensity oscillations in the solar corona during the total solar eclipse of 1995, we designed and fabricated a six-channel photometer incorporating low-noise Hamamatsu R647 photomultipliers. Fast photometry at five different locations in the solar corona was performed at Don Bosco Mission, Venezuela during the total solar eclipse of 26 February 1998. Three interference filters with passbands of about 150 Å and centered around 4700, 4900, and 5000 Å were used. The photometric data were recorded at a rate of 20 Hz in three channels and 50 Hz in the remaining three channels. The power spectrum analysis of one of the channels that recorded appreciable counts indicates the existence of intensity oscillations in the frequency range 0.01–0.2 Hz. A least-squares analysis yields 90.1, 25.2, and 6.9 s periods for the three prominent components which have amplitudes in the range 0.5–3.5% of the coronal brightness. These periods and their amplitudes are similar to those detected in the coronal intensity oscillations during the 1995 eclipse. 相似文献
17.
Suitable observations from various locations in the predicted path of a total solar eclipse can provide information about the relative positions and shapes of the Sun and Moon to about ±0.02. The total solar eclipse of 1972, July 10 was observed from locations near the edges of its predicted path. The durations of the limb phenomena were greatly enhanced. Preliminary analysis of the observations shows that the eclipse shadow passed 3 km northeast of its predicted path.Communication presented at the conference on Lunar Dynamics and Observational Coordinate Systems held January 15–17, 1973 at the Lunar Science Institute, Houston, Tex., U.S.A. 相似文献
18.
The structure and the shape of the solar corona during the total solar eclipse on March 29, 2006 were studied. The corona was of the intermediate pre-minimal type, it had northern and southern polar ray systems above the polar coronal holes and six streamers of different brightness in the middle and low heliographic latitudes. All the coronal structural features were found to have counterparts at the photosphere-chromosphere level on the limb and near it. The corona’s photometric flattening index was equal to 0.17. 相似文献
19.
R. M. Straka 《Solar physics》1971,21(2):469-480
Measurements were made of the 7 March, 1970 solar eclipse by the AFCRL Sagamore Hill Radio Observatory in Hamilton, Massachusetts, on the wavelengths of 0.86, 1.95, 3.4, 6.0, 11.1, 21.2, 49.5, and 122.5 cm. Near-total obscuration (m=0.96) occurred at eclipse maximum. Source flux spectra for the intense sources located in McMath plages 10 618(SE), 10617(NE), and 10 607(NW) show gyro-resonance spectral peaking, whereas the less intense bremsstrahlung emission is observed for the weaker sources in plages 10 614 and 10 619. Associated one-dimensional source sizes for these regions vary from 0.8 arc min (at 3.4 cm) to 5.4 arc min (at 49.5 cm); with sizes at a particular wavelength increasing with intensity of the source. An estimated flux spectrum of the undisturbed radio Sun for 7 March, 1970 is given and compared to the spectrum for the solar minimum of 1964. In plage 10 607 a weak halo emission was isolated from the intense emission from the central source over the spot. The measure of emission
from the halo above plage 10 607 was calculated to be 7 × 1027 electron2/cm5. 相似文献
20.
Ground measurements of the geomagnetic field, during the total solar eclipse of July 11, 1991, were carried out at three sites in Costa Rica located within the eclipse's path of totality. Near totality, there was a significant change in the total intensity,F. Its normal decrease in the afternoon hours was interrupted during a period of about 45 min, in whichF varied very little. This was due mainly to a small variation in horizontal intensity,H, during such a period. The departure ofF from normal lasted about 100 min; its maximum departure was near 10 nT and occurred about 38 min after totality, The declination,D, also experienced a small change (about 2.3 min) during the total period of the eclipse. The vertical intensity,Z, and the inclination,I, did not show significant changes. 相似文献