Eagle Nebula

The Eagle Nebula (catalogued as Messier 16 or M16, and as NGC 6611, and also known as the Star Queen Nebula and The Spire) is a young open cluster of stars in the constellation Serpens, discovered by Jean-Philippe de Cheseaux in 1745-46. Both the "Eagle" and the "Star Queen" refer to visual impressions of the dark silhouette near the center of the nebula, an area made famous as the "Pillars of Creation" photographed by the Hubble Space Telescope. The nebula contains several active star-forming gas and dust regions, including the Pillars of Creation.

Characteristics

The Eagle Nebula is part of a diffuse emission nebula, or H II region, which is catalogued as IC 4703. This region of active current star formation is about 7000 light-years distant. A spire of gas that can be seen coming off the nebula in the northeastern part is approximately 9.5 light-years or about 90 trillion kilometers long.

The cluster associated with the nebula has approximately 8100 stars, which are mostly concentrated in a gap in the molecular cloud to the north-west of the Pillars. The brightest star (HD 168076) has an apparent magnitude of +8.24, easily visible with good binoculars. It is actually a binary star formed of an O3.5V star plus an O7.5V companion. This star has a mass of roughly 80 solar masses, and a luminosity up to 1 million times that of the Sun. The cluster's age has been estimated to be 1–2 million years.

Eagle (disambiguation)

An eagle is a large bird of prey. There are dozens of eagle species, not all closely related to each other.

Eagle or The Eagle may also refer to:

People

Vehicles

Cars

Pillars of Creation

"Pillars of Creation" is a photograph taken by the Hubble Space Telescope of elephant trunks of interstellar gas and dust in the Eagle Nebula, some 7,000 light years from Earth. They are so named because the gas and dust are in the process of creating new stars, while also being eroded by the light from nearby stars that have recently formed. Taken on April 1, 1995, it was named one of the top ten photographs from Hubble by Space.com. The astronomers responsible for the photo were Jeff Hester and Paul Scowen from Arizona State University. In 2011, the region was revisited by ESA's Herschel Space Observatory.

Composition

The pillars are composed of cool molecular hydrogen and dust that are being eroded by photoevaporation from the ultraviolet light of relatively close and hot stars. The leftmost pillar is about four light years in length. The finger-like protrusions at the top of the clouds are larger than our solar system, and are made visible by the shadows of evaporating gaseous globules (EGGs), which shields the gas behind them from intense UV flux. EGGs are themselves incubators of new stars.

Eagle

Eagle is a common name for many large birds of prey of the family Accipitridae; it belongs to several groups of genera that are not necessarily closely related to each other.

Most of the 60 species of eagles are from Eurasia and Africa. Outside this area, just 14 species can be found – two in North America, nine in Central and South America, and three in Australia.

Description

Eagles are large, powerfully built birds of prey, with a heavy head and beak. Even the smallest eagles, like the booted eagle (Aquila pennata) (which is comparable in size to a common buzzard (Buteo buteo) or red-tailed hawk (B. jamaicensis)), have relatively longer and more evenly broad wings, and more direct, faster flight – despite the reduced size of aerodynamic feathers. Most eagles are larger than any other raptors apart from some vultures. The smallest species of eagle is the South Nicobar serpent eagle (Spilornis klossi), at 450 g (0.99 lb) and 40 cm (16 in). The largest species are discussed below. Like all birds of prey, eagles have very large hooked beaks for tearing flesh from their prey, strong muscular legs, and powerful talons. The beak is typically heavier than that of most other birds of prey. Eagles' eyes are extremely powerful, having up to 3.6 times human acuity for the martial eagle, which enables them to spot potential prey from a very long distance. This keen eyesight is primarily attributed to their extremely large pupils which ensure minimal diffraction (scattering) of the incoming light. The female of all known species of eagles is larger than the male.

Space observatory

A space observatory is any instrument (such as a telescope) in outer space that is used for observation of distant planets, galaxies and other outer space objects. The first such space observatory was the Hubble Space Telescope launched in 1990. Space observatories avoid many of the problems of ground observatories, such as light pollution and the filtering and distortion of electromagnetic radiation (scintillation).

This category is distinct from other observatories located in space that are pointed toward Earth for the purpose of reconnaissance and other types of information gathering.

History

In 1946, American theoretical astrophysicist Lyman Spitzer was the first to conceive the idea of a telescope in outer space, a decade before the Soviet Union launched the first satellite, Sputnik 1.

Spitzer's proposal called for a large telescope that would not be hindered by Earth's atmosphere. After lobbying in the 1960s and 70s for such a system to be built, Spitzer's vision ultimately materialized into the Hubble Space Telescope, which was launched on April 24, 1990 by the Space Shuttle Discovery (STS-31).