Next: Rotation Periods of ZAMS stars Previous: T Tauri Stars . ... The first attempts to directly measure periodic modulation of T Tauri stars occurred in the early 1980s. Rydgren & Vrba (1983) observed four PMS stars using photoelectric photometry over a period of seven consecutive photometric nights. ... Because the spot lifetime is much longer than the rotational period, the observed effect will be a modulation of the light from the star synchronously with the rotation period. ...

Next: PULSATION PROPERTIES Up: EXTREME HELIUM STARS: PULSATION Previous: EVOLUTION MODELS . ... These include a detailed comparison between models which predict evolution tracks and surface composition for a given stellar mass and accurate observations of stellar compositions and dimensions. ... Stellar pulsations provide much more powerful tools for determining stellar masses. ... Next: PULSATION PROPERTIES Up: EXTREME HELIUM STARS: PULSATION Previous: EVOLUTION MODELS Simon Jeffery . ...

HUBBLE SPACE TELESCOPE DAILY REPORT #1438 PERIOD COVERED: 0000Z (UTC) 07/21/95 - 0000Z (UTC) 07/24/95 Daily Status Report as of 205/0000Z 1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED: 1.1 Completed GHRS/2 5854 (Cepheid Masses) The High Resolution Spectrograph (Side Two) was used to make observations of the blue, main sequence companion of Cepheid star HD15679 to determine the mass of the system. ... Otherwise, the observations were completed as planned, and no problems were reported. ...

... The chemically peculiar star HD965 belongs to a rare type of very slow rotators. As far back as in the 90s, G.Mathys (ESO, Chile) supposed its extremely slow rotation as observing split Zeeman components in the spectrum, from which he measured the magnetic field on its surface. Field variation proved to be very slow, and G.Mathys determined that the variability period should be longer than two years. ... Up to now, only two stars with periods longer than 20 years are known. ...

Peremennye Zvezdy", . ... R_data_1.txt NSVS 547680 . ... Combined brightness of two stars: GSC 4347-01515 (= var) and GSC 4347-01707 (constant), was measured in the NSVS survey, thus the amplitude is considerably underestimated. ... The comparison star was GSC 4347-01707 and the check star, USNO-B1.0 1598-0075392. ... The comparison star was USNO-B1.0 1597-0078695 and the check star, USNO-B1.0 1598-0075495. ... The comparison star was GSC 3230-00588 and the check star, USNO-B1.0 1282-0605581. ...

Next: PEPSYS general photometry Up: Examples Previous: Period analysis . Let the two tables OBSERVA.tbl and OBSERVB.tbl contain two sets of observations. ... SET/CONTEXT TSA ! ... COVAR/TSA OBSERVA OBSERVA AUTOCOVA 1. ... PLOT/TAB AUTOCOVA :LAG :COVAR ! Plot autocov. function of `A' . COVAR/TSA OBSERVB OBSERVB AUTOCOVB ? ... PLOT/TAB AUTOCOVB :LAG :COVAR ! ... COVAR/TSA OBSERVA OBSERVB CROSSCOV ? ... PLOT/TAB CROSSCOV :LAG :COVAR ! Plot crosscovariance function . ... Astrophys. ...

... Previous: Generalized Linear Multi-Frequency Imaging in VLBI . ... At Astronomical Observatory of Valencia University (OAUV), CCD observations of asteroids and big planets satellites are obtained since 2001 with a big format camera and several telescopes. ... Software for comparison of single and overlapped CCD fields obtained at different epochs has been developed. ... After images measurement in CCD field, catalogue stars are identified and adjusted with images. ...

... The data-reduction path given in Chris Salter's IDL Cheat Sheet invovles a number of steps that are repeated for each observation. Onoffred is a wrapper program for the various AO IDL routines that are called, enabling an experienced observer to do file-loading, on-off data reduction, baseline fitting, smoothing and polarization averaging in a single step. ... The robust and user-defined profile windows can be hidden from the postscript output using the /hidelines switch. ...

... Among these objects, the newly discovered Kuiper Belt Objects (KBO's) outside the orbit of planet Neptune (also known as Trans-Neptunian Objects) are of particular interest, but the meeting was also concerned with distant comets and some of the small moons of the outer planets. ... The Kuiper Belt is a zone outside the orbits of Neptune and Pluto in which icy solar system objects were expected to be present; the first was found in 1992. ... ESO Press Photo 41/98 . ... Send comments to <ips@eso.org> ...

... It is known from preliminary observations that the period of this binary star is more than 8 hours but less than 12 hours. O. Struve & V. Zebergs (1959, ApJ, 130, 783) measured radial velocities of the two components and get the results presented at the enclosed "sheet of data". ... Plot graph of the velocities of components vs time. 8.2. Find exact orbital period of the components. ... Find exact orbital period, orbital radius and masses of the two components. ...

... There are result from two global VLBI observations at 3.6 cm spaced about 2 years. ... The analysis of the apparent motion, indication of the jet flow trajectory and the other implications for the CSS quasars are discussed. ... The quasar 3C380 ( ; thus 1 arcsec corresponds to 4 kpc for , ) is one of the most powerful radio sources (its radio luminosity at 2.7 GHz is ) ( Wilkinson et al. ... 3C380 is a member of the class of Compact Steep Spectrum (CSS) sources. ...

... CI Cam is known to be a B[e] star and X-ray transient source. ... Figure 1. The light curve of CI Cam in residuals relative to the mean level of the slow variability (top) . The radial velocity curve of the HeII emission (middle) . ... The V light curve is shown in Figure 1 (top). ... Comparison of two CI Cam spectra in the region of HeII line. ... The radial velocity curve of HeII in CI Cam has a saw-tooth shape that may be an evidence of an elliptical orbit. ...

. A tree for site navigation will open here if you enable JavaScript in your browser. HOME . ABOUT ST-ECF . CONTACT . Maintained by Martin Kuemmel <mkuemmel@eso.org> .

Last time we saw that flat rotation curves for galaxies, when measured in galaxies with extended gas distributions, provides unambiguous data that shows the mass distribution is dominated by an unseen, spherical halo. ... Perhaps only galaxies with extended dark matter halos are capable of retaining large gaseous extents? . ... Clusters of Galaxies: . ... The case of the Cancer cluster: . ... Below is the velocity distribution of galaxies in the Cancer cluster: . ... What's going on in Cancer? ...

We report first results of a multifrequency campaign from radio to hard X-ray energies of the prominent gamma-ray blazar 3C 279 during the first year of the INTEGRAL mission. The variable blazar was found at a low activity level, but was detected by all participating instruments. Subsequently a multifrequency spectrum could be compiled. ... In addition, this 2003 broadband spectrum is compared to one measured in 1999 during a high activity period of 3C 279. | ...

New reduction of minor planets photographic plates obtained with Pulkovo Normal Astrograph A.A. Berezhnoy Pulkovo Observatory of RAS, Saint-Petersburg, Russia Minor Planet observations at Pulkovo Periodical observations of 14 bright asteroids named Selected Minor Planets (SMP) were performed at Pulkovo since 1948 within the international framework started by works of B.V. Numerov and D. Brouwer. ... 108 133 113 74 124 67 97 88 14 84 64 5 20 19 Epochs (YYYY.MM) 1200 Mean values of total obs. ...

Nowadays at the Department the experimental and theoretical investigations, including astronomical and ionospheric observations, active experiments with space vehicles are taking place. ... Solar Corona physics and erruptive phenomenae. ... Stellar astronomy. ... The Department has organized and put into practice more then 50 expeditions for observation of Solar ecllipces, aurorae polaris, comets, meteor streams, controlled space experiments, and also for investigations of geophysical characteristics. ...

Amalthea . Jupiter V . Amalthea [am-al-THEE-uh] is one of Jupiter's smaller moons. ... These four images of Jupiter's moon, Amalthea, were taken by Galileo's solid state imaging system at various times between February and June 1997. ... Amalthea, whose longest dimension is approximately 247 kilometers (154 miles) across, is tidally locked so that the same side of the satellite always points towards Jupiter, similar to how the near side of our own Moon always points toward Earth. ...

The large magnetic cloud caused by coronal mass ejection at the Sun on January 6, 1997 came to the Earth at early morning on January 10 and continue to interact with Earth's magnetosphere till January 11 (see for example home page of this event prepeared by Dr. M.Peredo http://www-istp.gsfc.nasa.gov/istp/cloud_jan97/event.html ). ... During the days discussed here INTERBALL-1 satellite was in the magnetosphere (MS) near its dusk flunk - see the Fig. 1 for compearing. ...

Amalthea . Jupiter V . Amalthea [am-al-THEE-uh] is one of Jupiter's smaller moons. ... It was also the first moon of Jupiter to be discovered since Galileo's discovery of the four Galilean Moons in 1610. Amalthea is extremely irregular, having dimensions of about 270x165x150 kilometers in diameter. ... Discovered by . ... Topographic Map of Amalthea . ... As with all maps, it is the cartographer's interpretation; not all features are necessarily certain given the limited data available. ...