Search results
Results From The WOW.Com Content Network
A color–color diagram is a means of comparing the colors of an astronomical object at different wavelengths. Astronomers typically observe at narrow bands around certain wavelengths, and objects observed will have different brightnesses in each band. The difference in brightness between two bands is referred to as an object's color index, or ...
A subtype of Secchi class I with narrow lines in place of wide bands, such as Rigel and Bellatrix. In modern terms, this corresponds to early B-type stars Secchi class II: Yellow stars – hydrogen less strong, but evident metallic lines, such as the Sun, Arcturus, and Capella. This includes the modern classes G and K as well as late class F.
Photometric system. In astronomy, a photometric system is a set of well-defined passbands (or optical filters ), with a known sensitivity to incident radiation. The sensitivity usually depends on the optical system, detectors and filters used. For each photometric system a set of primary standard stars is provided.
Performed by the United States Marine Band. file. help. " The Stars and Stripes Forever " is a patriotic American march written and composed by John Philip Sousa in 1896. By a 1987 act of the U.S. Congress, it is the official National March of the United States of America. [1]
Astronomical spectroscopy is the study of astronomy using the techniques of spectroscopy to measure the spectrum of electromagnetic radiation, including visible light, ultraviolet, X-ray, infrared and radio waves that radiate from stars and other celestial objects. A stellar spectrum can reveal many properties of stars, such as their chemical ...
Radio astronomy. The Karl G. Jansky Very Large Array, a radio interferometer in New Mexico, United States. Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The first detection of radio waves from an astronomical object was in 1933, when Karl Jansky at Bell Telephone Laboratories reported radiation ...
CN star. A CN star has unusually strong cyano radical bands in its spectrum compared to other stars of its stellar class. [1] Cyano radical is a simple molecule of one carbon atom and one nitrogen atom, with absorption bands around wavelengths 388.9 and 421.6 nanometer. [2] This group of stars was first noticed in certain G and K-type giants by ...
The next brightest stars in the J band are Antares (−2.7), R Doradus (−2.6), Arcturus (−2.2), and Aldebaran (−2.1). In the J band Sirius is the 9th brightest star. The J band is a frequent source of ground based observations since the wavelengths it covers pass through clouds and other atmospheric gasses.