... Aurora from Space . ... Magnetic Storms . ... The "ring of fire" seen by satellite cameras around the polar caps (picture below) is probably created by electrons leaking from the tail's plasma sheet, whose magnetic field lines form a somewhat imperfect trap. ... One possible explanation involves the close association between auroral arcs and electric currents which flow along field lines between the ionosphere and distant space ( Birkeland currents ). ... Why no aurora at the magnetic poles? ...

... The planets differ greatly in size and properties, and their fields differ too. ... In 1959, after the Earth's radiation belt had been discovered, Frank Drake observed Jupiter and concluded from the relative intensities in a range of wavelengths that the signal was probably emitted by electrons trapped in a strong magnetic field. Then in 1973 the space probe Pioneer 10 passed by Jupiter and found there, sure enough, an enormous planetary magnetic field and a very intense radiation belt. ...

... Home Observing Central Park ? ... Beyond New York City . ... Observing Resources for Amateur Astronomers - Part 1: Beginning Observers . ... A History of the First Forty Years of the Amateur Astronomers Association . ... The AAA hosts solar observing in Central Park one Sunday afternoon€аeach month.€а WeтАЩre located right by Bethesda Terrace and Fountain , middle of Central Park, just north of 72nd street. ... 2016 Amateur Astronomers Association of New York Designed by Press Customizr Powered by ....

... 1995, Cycle 5, GO-5847 , PI, 9 orbits. The nuclear disk in the E4 radio galaxy NGC 7052: evidence for a central black hole? ... 1996/97, Cycle 6, GO-6537 , CoI, 8 orbits. ... Nuclear kinematics of the dense globular cluster M15 . ... A Census of Nuclear Star Clusters in Late-Type Spiral Galaxies . ... A Census of Nuclear Star Clusters in Late-Type Spiral Galaxies: II - Spectroscopy and Stellar Populations . ... The Ages of Nuclear Star Clusters in Early-type Spiral Galaxies . ...

Direct images gallery. Here we have presented some images obtained on SAO telescopes by using SCORPIO. ... NGC 6951 . ... This color image are combined from the frames in the filters V ("blue"), R ("green") and middle-band filter SED755 ("red"). ... The true color image is constructed from three frames in B (Texp=600 sec), V (Texp=480 sec) and R (Texp=400 sec) filters. ... The true color image is constructed from three frames in B (Texp=180 sec), V (Texp=120 sec) and R (Texp=90 sec) filters. ...

Next: The derived luminosity and Up: The galactic population of Previous: The galactic population of . Figure 16: The observed distribution of pulsar dispersion measures. Dotted curve is the total known population, solid curve is the Parkes survey. Figure 17: The observed distribution of pulsar distances above the galactic plane. ... Figure 18: The observed distribution of pulsar flux densities. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Three sixth-form students from St Patrick's Grammar School, Armagh , used the Faulkes Telescope South in Australia in April to observe and measure HW Virginis , an unusual "binary" or double star system suspected to host one or two extrasolar planets orbiting the central stellar pair. ... Armagh Observatory and associated researchers hope to develop this work to look for further evidence of planet-hosting binary star...

... M94 or NGc 4736 is an early type spiral galaxy with tightly would spiral structure and a dominant, luminous central bulge. ... This exposure was for 1724 seconds through A1 and B1. ... NGC 7789 is an open stellar cluster in the Galaxy. This exposure is 1351 seconds through B5. ... The Coma Cluster of galaxies was observed for 1850 seconds through the A1 filter. ... NGC 1313 A spiral galaxy in the Fornax Cluster and host of two recent supernova was observed for 1384 seconds through A1 and B5. ...

In 1950 Jan Oort noticed that . no comet has been observed with an orbit that indicates that it came from interstellar space, . ... From this he proposed that comets reside in a vast cloud at the outer reaches of the solar system. ... Unfortunately, since the individual comets are so small and at such large distances, we have no direct evidence about the Oort Cloud. ... Its orbit is intermediate between the Kuiper Belt and what was previously thought to be the inner part of the Oort Cloud. ...

Next: The Gravimagnetic Parameter Up: ``Ecology'' of Magnetic Rotators Previous: Nomenclature . ... One can introduce two critical periods and such that their relationship with period p of a magnetic rotator specifies the rotator's type: . ... Instead of , we introduce the potential accretion luminosity L . ... Treating the rotator's magnetic dipole moment and as parameters, we find that an overwhelming majority of the magnetor's stages can be shown on a `` '' diagram (Lipunov 1982a[ 98 ]). ...

... See "About ATMoB" / "Network" for more details on the clubhouse network. ... Direct viewing of a laser-pointer beam, even briefly and at a distance of a kilometer or two, has the potential to cause temporary flash blindness — the same effect you get right after a flash photo is taken — or afterimages. ... To help use our laser tools safely, the Amateur Telescope Makers of Boston, Inc. has adopted these recommendations as policy. ... Copyright (c) Amateur Telescope Makers of Boston, Inc. ...

... Master . Master net Homepage . ... MASTER-Amur . ... Amb: . Dust: . ... Direct . 23s . ... 45s . ... observed area: . best limit: . Cameras . ... MASTER-Tunka . ... MASTER-Ural . master.kourovka.ru . ... MASTER-Kislovodsk . ... MASTER-Crimea . ... MASTER-SAAO . ... MASTER-IAC . ... MASTER-Argentina . master.sai.msu.ru:8080 . master.sai.msu.ru . ...

... 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! ...

... Spherical aberration, coma, and astigmatism are also easily observed using the star test. ... Off-axis images are complex. ... Fig. ... Diffraction by a circular aperture as a function of defocus for no aberration Airy Disk 1 wave defocus Less than 1 wave defocus Fig. ... Diffraction by a circular aperture as a function of defocus for third-order spherical aberration Paraxial Focus Small distance inside paraxial focus Moderate distance from marginal focus Immediate neighborhood of marginal focus Fig...

... The ChaMPlane survey is being conducted at the Harvard-Smithsonian Center for Astrophysics. The ChaMPlane team is conducting a "Bulge Latitude Survey" (BLS) to measure the latitude distribution of faint X-ray point sources in the region b = +/- 1.5њ, l = +/- 0.35њ centered at l = 0њ. ... In Chandra cycle 7, two-thirds of the region below the galactic plane were observed (BLS-Sa); observations of a similar-sized region above the plane (BLS-Na) are planned for cycle 8 (summer 2007). ...

... I had also observed that comet in 1994, as it passed the halfway mark (January 1994): observation of the faintest solar system object ever observed. [at that time]. ... We observed it at the 2.2m at ESO in Mar.2001; here is a nice color image (and is also available in Italian , in Hebrew elsewhere.. ... The IfA Hale-Bopp page contains plenty of info and links about that comet; for nice pictures, check out the Images and Spectra page . ... Olivier R. Hainaut (ohainaut at eso.org) . ...

... One of this year's largest mass ejections from the Sun's atmosphere was recorded last Sunday by TESIS telescopes aboard the CORONAS-PHOTON satellite ( video - wmv 4.3 MB ). ... Over the course of a week, two gigantic solar prominences were simultaneously ejected from the surface of the Sun. ... Earth will not feel the Sun's influence either. ... The TESIS observatory ї TESIS: www.tesis.lebedev.ru . ... One of this year's largest mass ejections from the Sun's atmosphere (movie WMV, 4.3 MB) . ...

The AstroGuide . ... AstroGuide | ... AstroGuide Listing . Login . See many more Astronomy Listings by: Category or Alphabet . CPO was formed in 1997 to promote interest in amateur astronomy and observing the wonders of the night sky. ... Listed Since July 15, 1998 . ... Web Site . ... Web . ... Unless otherwise specified, web site content Copyright 1994-2016 John Huggins All Rights Reserved . dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . are trademarks of John Huggins ...

... Fitting the observed dependence includes calculations of the polarization cross-sections averaged over particles orientation and size distribution, their normalization and the comparison of obtained dependencies with Serkowski's curve representing observational data for a chosen star. ... Variations of the polarization factors with wavelength are shown in Fig. 16 for homogeneous spheroidal particles with PF orientation. ... The distinction between prolate and oblate spheroids is also clearly seen. ...