... The concerns here are similar to those for observing bright targets; saturation and blooming of the bright companion PSF must not impact the faint target. Also, one may need to consider subtracting the PSF of the bright object, and effects which limit the accuracy of that subtraction. If the bright companion will saturate and bloom, it will be necessary to rotate the CCD so that blooming along the CCD columns does not obliterate the faint target. ...

... A detailed study of two consecutive bright points observed simultaneously with CDS, EIT and MDI is presented. The analysis of the evolution of the photospheric magnetic features and their coronal counterpart shows that there is a linear dependence between the EIT Fe XII 195? flux and the total magnetic flux of the photospheric bipolarity. ... In a follow-up study, we used wide slit (90arcsec240arcsec) movies of four EIT coronal bright points (BPs) obtained with CDS. ...

The CHIANTI database consists of 4 primary ASCII files for each ion in the database. contains the energy levels in cm^(-1) It includes both experimental data and theoretical values of the levels energies. References: %observed energy levels (n=2): Fuhr, J.R., et al., NIST Atomic Spectra Database" ver. ... NIST Physical Reference Data %observed energy levels (12,19,23-26,65-67,69,70,72-74,78-82,84,85): Fuhr, J.R., et al., ...

In this gallery are many images of Low Surface Brightness Galaxies which have recently been discovered and analyzed. ... The central surface brightness of this galaxy is 24.28 . Malin 2 This galaxy is another huge disk galaxy with a scale length of 15 kpc and a redshift of 15000 km/a. The high surface brightness knot in one of its spiral arms actually has the same color, luminosity and H-alpha equivalent width as the entire Large Magellanic Cloud . ... Truly it is a Low Surface Brightness Galaxy. ...

Next: This Work Previous: Rotation Periods of ZAMS Stars . ... There are currently several groups involved in the studies of the rotation periods of PMS stars. ... Overall, there are about 100 rotation periods known for PMS stars. ... Furthermore, the stars with periods near 8 days also tend to have infrared excesses which can be interpreted as arising from disks. ... In the first interpretation, the gap occurs because locking mechanism holds stars at a eight day rotation period. ...

... Science User Portal . ... ESO, the European Southern Observatory . ... Travel and Contacts . Travel to ESO Headquarters . ... Travel to E-ELT Armazones . ... Survey Telescopes . ... Star Clusters . ... Stars@ESO . ... ESO Science Newsletter . ... ESO 3.6-metre telescope . ... MPG/ESO 2.2-metre telescope . ... ESO 1-metre Schmidt telescope . ... ESO Science Outreach Network . ... This chart shows the brightness variation ("light-curve") of the star OGLE-TR-3 obtained during the OGLE observations. ...

SAS home . ... This thread contains a step-by-step recipe to extract PN spectra of a point-like source observed in Imaging mode and to create associated response matrices, starting from a calibrated, concatenated event list (either produced with epproc or available as PPS product; here it has the assumed file name PN.fits ). ... The users should note that the SAS metatask xmmselect allows them to interactively define source and background regions (via ds9) and to run backscale on the fly. ...

The Sun is our nearest star and the source of energy for life on Earth. ... For centuries astronomers wondered whether they were clouds floating in the Sun's atmosphere, but we now know that they really are huge regions of magnetic field, about as intense as the field at the poles of an iron magnet. ... Such abrupt events were named solar flares , and what made them especially interesting was that occasionally, after a prominent flare, a magnetic storm would erupt on Earth. ...