The nasa.gov site requires that JavaScripts be enabled in your browser. ... Contact NASA . ... The term "astronaut" derives from the Greek words meaning "space sailor," and refers to all who have been launched as crew members aboard NASA spacecraft bound for orbit and beyond. Since the inception of NASA's human space flight program, we have also maintained the term "astronaut" as the title for those selected to join the NASA corps of astronauts who make "space sailing" their career profession. ...

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. ...

... Dark Markings of the Sky . ... Credit: Steve Cannistra ( StarryWonders ) Explanation: Based on wide field photographs, American astronomer Edward Emerson Barnard cataloged the dark markings of the sky in the early 20th century. Barnard's markings are dark nebulae, interstellar clouds of obscuring gas and dust. ... NASA Web Site Statements, Warnings, and Disclaimers . ... Публикации с ключевыми словами: dark nebula - темная туманность . Публикации со словами: dark nebula - темная туманность . ...

... We discuss the application of the Pixon Based Image Restoration Method on spectroscopic HST data and compare the results with those obtained from the Richardson-Lucy and Jansson algorithms. In order to better evaluate the performance of the various algorithms we have also used artificial data. Keywords: Spectral restorations, Pixons, Richardson-lucy, Jansson . ...

... Up: Science Software Applications . ... It has extensions for creating GUI (Tk) and object-oriented ([incr tcl]) applications. Several Tcl-based tools that may be used for astronomical and other scientific applications have been created and are discussed. One example is ptcl , which registers PGPLOT functions as Tcl commands, creating a powerful interactive plotting package. ... Both programs use the same C code, Tcl commands, and [incr tcl] classes; only the GUIs are different. ...

... Often it is convenient to edit one visibility dataset (``the template''), and then to apply the flagging from this to another. For example, forming and flagging a ``channel-0'' dataset might be less painful than flagging a huge spectral line dataset. ... The task that can do these sorts of operations if uvaflag - it matches visibilities in the template and the input, and flags those visibilities in the input that are flagged in the template. ... Dataset to be flagged. tvis=multi.chan0 . ...

... Apache HTTP Server Version 2.4 . Apache > HTTP Server > Documentation > Version 2.4 > Virtual Hosts . ... IP-based virtual hosting is a method to apply different directives based on the IP address and port a request is received on. ... As the term IP-based indicates, the server must have a different IP address/port combination for each IP-based virtual host . ... In the terminology of Apache HTTP Server, using a single IP address but multiple TCP ports, is also IP-based virtual hosting. ...