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. ...

Weekly Bulletin on Solar and Geomagnetic Activity Highlights on 17 - 23.02.2014, Forecast on 24.02 - 02.02.2014 , Carrington Rotation 2147 (11,73.02.2014) SUNSPOT-FORMING ACTIVITY REMINDER AT MEDIUM AND HIGH LEVELS, GRA- DUALLY INCREASING TOWARDS THE END OF PERIOD. ... NEXT WEEK IS EXPECTED THE HIGH AND THE MODERATE LEVELS OF SUNSPOT- FORMING ACTIVITY. ... FLARE ACTIVITY WAS AT THE MODERATE LEVEL 20 AND 23.02, AND THE LOW LEVEL IN OTHER DAYS. ... G - geoeffectivity in last solar rotation; A - active. ...

P. Frisch - Warm partially ionized interstellar gas at the Sun . ... W. M. Goss - Time variations in small-scale galactic HI structure toward 3C138 . S. Stanimirovic - Does tiny-scale atomic structure exist in the ISM? ... T. Bania - The distance to molecular clouds via HI self-absorption . ... C. Heiles - Arecibo Millennium Survey statistics of magnetic field, column density and turbulence in the CNM . R. Crutcher - Magnetic fields in molecular clouds . ...

... The most spectacular view however is from space, where large areas of aurora can be observed simultaneously, even the entire polar cap. ... Such pictures often show a continuous ring of aurora around the polar cap (picture above), caused mostly by electrons leaking out along magnetic field lines, from the plasma sheet of the Earth's magnetic tail. ... Field lines from the auroral oval are believed to lead to the plasma sheet. ... A near-Earth circular polar orbit has many uses. ...

Russian SHAREABLE DATA CENTER Institute of Solar-Terrestial Physics SB RAS . ... Investigations of the ionospheric response to strong magnetics storms which are usual for our latitudes, are of great interest. ... In the figure, we present ionospheric parameter dynamics during three perturbed days in July 2000. ...

... The TRACE images may be used without restrictions in publications of any kind. ... These two images, taken on 18 November 2000 at 15:54UT and 16:11UT, respectively, show such an event: the red circle in the image to the left shows a region where many loops are cooling, with bright loop tops (the intensity scales with the square root of the image to reduce the dynamic range). ... See also a collection of images related to the Sun, other cool stars, and solar-terrestrial effects . ... Images | ...

Next: Radio pulse characteristics Up: An overview Previous: The structure of neutron . Typically Gauss for normal pulsars . Consistent with flux conservation during stellar collapse . ... Gravity dominates stellar structure . B field dominates exterior . Stellar surface is so small that observed emission is dominated by the magnetic field. ... Only field lines inside light cylinder are closed . Particles are constrained move along field lines . ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... The stars of the middle main sequence have relatively quiescent outer layers, and unusual chemical abundance patterns may develop in their atmospheres. ... At present, little is known about the time evolution of these anomalous abundances, nor about the role that diffusion may play in maintaining them, during the main sequence lifetime of such a star. ...

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. ...

Magnetic Fields around Radio Galaxies Robert Laing (ESO) Laing et al. ... 2008) Negligible depolarization and 2 rotation Almost all Faraday effects must be due to foreground material How to fit depolarization caused by foreground Faraday rotation Complex polarization Rotation measure Integrate over a beam Observed RM for 0 2 rotation and depolarization Faraday rotation and depolarization 5.5 arcsec FWHM Faraday effects at high resolution FWHM = 1.5 ...

... The improvement will be more pronounced in our crowded Wide Field Camera (WFC) images, and may be increased further through use of a more sophisticated method of combining the individual dithered images. Our analysis allows us to check for point spread function shape variations in the HST Planetary Camera (PC) field. ... In crowded field images, we are deriving information about the faint end of the luminosity function (LF) from the texture of the image background. ...

... The Circinus Galaxy . ... Earth's North Magnetic Pole . ... A magnetic compass does not point toward the true North Pole of the Earth. Rather, it more closely points toward the North Magnetic Pole of the Earth. The North Magnetic Pole is currently located in northern Canada. ... Globular star cluster Palomar 13 has roamed the halo of our Milky Way Galaxy for the last 12 billion years. ... Here is what a meteor shower looks like from orbit. ... Earth at Night . ... Next [ Last page ] . ...

... A demonstration of HST WFPC image restoration has been made using both empirical and simulated PSFs. Empirical PSFs are obtained from the WFPC PSF library and also extracted from the image to be restored. ... The best results obtained thus far rely upon being able to determine a high S/N empirical PSF from the data frame. In order to achieve accurate restorations of data with high dynamic range excellent PSF models are required. ... Keywords: image restoration, HST WFPC image, PSFs . ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. October 19, 1999 . Earth's North Magnetic Pole . ... Explanation: A magnetic compass does not point toward the true North Pole of the Earth. ... Evidence indicates that the North Magnetic Pole has wandered over much of the Earth's surface in the 4.5 billion years since the Earth formed. ... About APOD > . ...

... Science Users Information > Science and Technical Meetings > Conferences 2010 > The Origin and Fate of the Sun: Evolution of Solar-mass Stars Observed with High Angular Resolution . ... Observing Facilities . ... Observing with ESO Telescopes . ... The goal of this workshop is to review recent results on solar-mass stars obtained with infrared and millimeter interferometers, and to discuss their importance for our understanding of stellar evolution from star formation to stellar end products. ...

... Sun images . Magnetic storms online . ... Geomagnetic activity forecast . ... March : 2012 . ... No geomagnetic storms were observed for the past 3 hours Geomagnetic storms were observed for the past 24 hours . Magnetic storm of level G1 (minor) from 00:00 to 03:00 UT . Magnetic storm of level G2 (moderate) from 03:00 to 06:00 UT . Magnetic storm of level G3 (strong) from 06:00 to 09:00 UT . ... Last updated: March 10, 2012 00:00 UT . ... 7(499)132-65-96, Fax: +7(499)132-65-97 . ...

... About ATMoB . ... The Observing Committee is starting an Observing Awards Program to promote observing among the membership of the Amateur Telescope Makers of Boston. ... Participant must be a current member of the Amateur Telescope Makers of Boston . ... To qualify for your Observing Award Certificate, turn in your worksheet and drawings to an ATMoB Observing Committee member or observing@atmob.org . ... This Excel sheet has useful macros. ... Copyright (c) Amateur Telescope Makers of Boston, Inc. ...

... 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. ...

... SUN MOON MERCURY VENUS MARS, JUPITER SATURN . ... Mars . ... Previously understood that magnetic fields were directly related to rotation, so when I read that Mars, like Venus, didn't have one, my understanding crumbled. What exactly causes magnetic fields in planets? ... RELATED TOPICS: MAGNETIC FIELD . Planetary magnetic fields are definitely related to rotation, but directly not so much. ... Get instant access to subscriber content on Astronomy.com! ...