NGC 6044 is a lenticular galaxy located about 465 million light-years away in the constellation Hercules. NGC 6044 was discovered by astronomer Lewis Swift on June 27, 1886, it was rediscovered by astronomer Guillaume Bigourdan on June 8, 1888. NGC 6044 is a member of the Hercules Cluster. List of NGC objects NGC 6039 NGC 6044 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Sky Map and images
NGC 6045 is a barred spiral galaxy located about 450 million light-years away in the constellation Hercules. NGC 6045 was discovered by astronomer Lewis Swift on June 27, 1886 and is a member of the Hercules Cluster, it is a LINER galaxy. NGC 6045 is luminous in both X-ray and Infrared light; this high luminosity in both X-ray and Infrared has been suggested to be the result of a starburst event in the galaxy. It is thought that starburst events are caused by mergers with other galaxies. NGC 6045 has a warped disk which may be due to an interaction with the elliptical galaxy NGC 6047 which lies around ~320,000 ly from the galaxy. List of NGC objects Messier 82 NGC 6872 NGC 6045 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Sky Map and images
NGC 6052 is a pair of galaxies in the constellation of Hercules. It was discovered on 11 June 1784 by William Herschel, it was described as "faint, pretty large, irregularly round" by John Louis Emil Dreyer, the compiler of the New General Catalogue. The two components of NGC 6052 are designated NGC 6052B, respectively; the two, attracted by each other's gravity, are interacting with each other. NGC 6052 is in a late stage of merging, where the shape of the two galaxies is not distinctly defined. SN 1982aa, a powerful radio supernova, was detected in NGC 6052
NGC 6041 is a giant elliptical galaxy located about 470 million light-years away in the constellation Hercules. NGC 6041 has an extended envelope, distorted towards the galaxy pair Arp 122. NGC 6041 is the brightest galaxy in the Hercules Cluster; the galaxy was discovered by astronomer Édouard Stephan on June 27, 1870. List of NGC objects Messier 87 NGC 1399 NGC 4874 NGC 4889 NGC 6041 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Sky Map and images
The apparent magnitude of an astronomical object is a number, a measure of its brightness as seen by an observer on Earth. The magnitude scale is logarithmic. A difference of 1 in magnitude corresponds to a change in brightness by a factor of 5√100, or about 2.512. The brighter an object appears, the lower its magnitude value, with the brightest astronomical objects having negative apparent magnitudes: for example Sirius at −1.46. The measurement of apparent magnitudes or brightnesses of celestial objects is known as photometry. Apparent magnitudes are used to quantify the brightness of sources at ultraviolet and infrared wavelengths. An apparent magnitude is measured in a specific passband corresponding to some photometric system such as the UBV system. In standard astronomical notation, an apparent magnitude in the V filter band would be denoted either as mV or simply as V, as in "mV = 15" or "V = 15" to describe a 15th-magnitude object; the scale used to indicate magnitude originates in the Hellenistic practice of dividing stars visible to the naked eye into six magnitudes.
The brightest stars in the night sky were said to be of first magnitude, whereas the faintest were of sixth magnitude, the limit of human visual perception. Each grade of magnitude was considered twice the brightness of the following grade, although that ratio was subjective as no photodetectors existed; this rather crude scale for the brightness of stars was popularized by Ptolemy in his Almagest and is believed to have originated with Hipparchus. In 1856, Norman Robert Pogson formalized the system by defining a first magnitude star as a star, 100 times as bright as a sixth-magnitude star, thereby establishing the logarithmic scale still in use today; this implies that a star of magnitude m is about 2.512 times as bright as a star of magnitude m + 1. This figure, the fifth root of 100, became known as Pogson's Ratio; the zero point of Pogson's scale was defined by assigning Polaris a magnitude of 2. Astronomers discovered that Polaris is variable, so they switched to Vega as the standard reference star, assigning the brightness of Vega as the definition of zero magnitude at any specified wavelength.
Apart from small corrections, the brightness of Vega still serves as the definition of zero magnitude for visible and near infrared wavelengths, where its spectral energy distribution approximates that of a black body for a temperature of 11000 K. However, with the advent of infrared astronomy it was revealed that Vega's radiation includes an Infrared excess due to a circumstellar disk consisting of dust at warm temperatures. At shorter wavelengths, there is negligible emission from dust at these temperatures. However, in order to properly extend the magnitude scale further into the infrared, this peculiarity of Vega should not affect the definition of the magnitude scale. Therefore, the magnitude scale was extrapolated to all wavelengths on the basis of the black-body radiation curve for an ideal stellar surface at 11000 K uncontaminated by circumstellar radiation. On this basis the spectral irradiance for the zero magnitude point, as a function of wavelength, can be computed. Small deviations are specified between systems using measurement apparatuses developed independently so that data obtained by different astronomers can be properly compared, but of greater practical importance is the definition of magnitude not at a single wavelength but applying to the response of standard spectral filters used in photometry over various wavelength bands.
With the modern magnitude systems, brightness over a wide range is specified according to the logarithmic definition detailed below, using this zero reference. In practice such apparent magnitudes do not exceed 30; the brightness of Vega is exceeded by four stars in the night sky at visible wavelengths as well as the bright planets Venus and Jupiter, these must be described by negative magnitudes. For example, the brightest star of the celestial sphere, has an apparent magnitude of −1.4 in the visible. Negative magnitudes for other bright astronomical objects can be found in the table below. Astronomers have developed other photometric zeropoint systems as alternatives to the Vega system; the most used is the AB magnitude system, in which photometric zeropoints are based on a hypothetical reference spectrum having constant flux per unit frequency interval, rather than using a stellar spectrum or blackbody curve as the reference. The AB magnitude zeropoint is defined such that an object's AB and Vega-based magnitudes will be equal in the V filter band.
As the amount of light received by a telescope is reduced by transmission through the Earth's atmosphere, any measurement of apparent magnitude is corrected for what it would have been as seen from above the atmosphere. The dimmer an object appears, the higher the numerical value given to its apparent magnitude, with a difference of 5 magnitudes corresponding to a brightness factor of 100. Therefore, the apparent magnitude m, in the spectral band x, would be given by m x = − 5 log 100 , more expressed in terms of common logarithms as m x
NGC 6047 is an elliptical galaxy located about 430 million light-years away in the constellation Hercules. It was discovered by astronomer Lewis Swift on June 27, 1886. NGC 6047 is a member of the Hercules Cluster. NGC 6047 has a peculiar morphologywhich. NGC 6047 is classified as a FR I radio galaxy; the jets appear to have a Z-shaped structure. NGC 6047 may be interacting with NGC 6045. List of NGC objects NGC 1128 NGC 6047 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Sky Map and images
NGC 6054 is a barred lenticular galaxy located about 460 million light-years away in the constellation Hercules. It was discovered by astronomer Lewis Swift on June 27, 1886, it was rediscovered by astronomer Guillaume Bigourdan on June 1, 1888. PGC 57073 is misidentified as NGC 6054. NGC 6054 is a member of the Hercules Cluster. List of NGC objects NGC 6054 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Sky Map and images http://ngcicproject.org/NGC/NGC_60xx/NGC_6054.htm http://www.astronomy-mall.com/Adventures. In. Deep. Space/NGC%206000%20-%206999%20.htm