... Three energetic mechanisms are considered: multiple supernova explosions (SNe), a hypernova explosion associated with a gamma ray burst (GRB), and the vertical impact of a high velocity cloud (HVC). ... As a consequence, multiple SNe form rings with a high ring-to-center contrast K < 100 in the HI column density, whereas single hypernova explosions form rings with K < 10. ... Our simulations show (see Fig. 6) that both multiple SNe and single hypernovae may form rings of up to 2 kpc in diameter. ...

AAL Guestbook . Please Sign Our Guestbook . Guestbook Entries: 147 . ... Previous Page | Next Page . ... Luxembourg, Luxembourg . ... Signed on Monday, June 18, 2001 at 23:14:35 CET . ... AAL-Page is the best astronomy source in Luxembourg! ... Special Greetings to a mysterious fairy in the AAL :-) . ... L-5823 FENTANGE, LUXEMBOURG . ... Signed on Sunday, June 17, 2001 at 23:42:48 CET . ... Signed on 02/06/2001 at 11:55:12pm . ... Signed on 25/04/2001 at 5:56:01 am . ...

Please enter the lightcurve file name and period search parameters: . Lightcurve file: . ... Apply the Heliocentric correction and convert all dates to Terrestrial Time (TT)? ... Also, the Heliocentric correction cannot be applied to such lightcurves. ... This period search service is also available at the mirror sites: Mirror 1 , Mirror 2 , Mirror 3 , Mirror 4 . You may download the latest source code distribution and install the period search service at your own web server. ...

... Pulkovo Astrometric Observations of Bodies in the Solar System from 1898 to 2005: Observational Database T. P. Kiseleva and E. V. Khrutskaya Pulkovo Astronomical Observatory, Russian Academy of Sciences, Pulkovskoe sh. ... The long-term work resulted in long, homogeneous series of observations of various bodies in the Solar System: Venus, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto; the satellites of Mars, Jupiter, and Saturn; selected minor planets, asteroids, and comets. ... 2001; Kiseleva et al...

... Imaging GRIN Rod Lens (HAG's) | Relay Rod Lens (LAG's) | ... The Refractive Index Distributions (RID) in GRIN lens preforms are made by multi-stage optimized ion-exchange diffusion between silicate mineral glasses and salt melts. ... In the LAG lenses - L ow A perture GRIN the nature of the changing of refractive index in glass via ion-exchange lies mainly in molecular volume increase. ... LAG lenses are specially treated to create the dark anti-flick surface coating (Fig.2). ...