Solar System - creating a bubble

The Solar System consists of the Sun and those celestial objects bound to it by gravity: the eight planets and five dwarf planets, their 173 known moons,and billions of small bodies. The small bodies include asteroids, icy Kuiper belt objects, comets, meteoroids, and interplanetary dust.

The charted regions of the Solar System comprise the Sun, four terrestrial inner planets, the asteroid belt, four gas giant outer planets, and finally the Kuiper belt and the scattered disc. The hypothetical Oort cloud may also exist at a distance roughly a thousand times beyond these regions.

The solar wind, a flow of plasma from the Sun, permeates the Solar System, creating a bubble in the interstellar medium known as the heliosphere, which extends out to the middle of the scattered disc.

The Realm of the Nebulae

An elliptical galaxy is a galaxy having an approximately ellipsoidal shape and a smooth, nearly featureless brightness profile. They range in shape from nearly spherical to highly flattened and in size from hundreds of millions to over one trillion stars.

Elliptical galaxies are one of the three main classes of galaxy originally described by Edwin Hubble in his 1936 work “The Realm of the Nebulae”, along with spiral and lenticular galaxies.

Most elliptical galaxies are composed of older, low-mass stars, with a sparse interstellar medium and minimal star formation activity. They are surrounded by large numbers of globular clusters. Elliptical galaxies are believed to make up approximately 10-15% of galaxies in the local Universe but are the dominant type of galaxy in the universe overall. They are preferentially found close to the centers of galaxy clusters and are less common in the early Universe.

Galactic Center -rotational center of the Milky Way

The Galactic Center is the rotational center of the Milky Way galaxy. It is located about 7.6 kilo parsecs (25,000 ly) away from the Earth in the direction of the constellations Sagittarius, Ophiuchus, and Scorpius where the Milky Way appears brightest. There is a suspected super massive black hole at the Galactic Center of the Milky Way.

Because of interstellar dust along the line of sight, the Galactic Center cannot be studied at visible, ultraviolet or soft X-ray wavelengths. The available information about the Galactic Center comes from observations at gamma ray, hard X-ray, infrared, sub-millimeter and radio wavelengths.

Coordinates of the Galactic Center were first found by Harlow Shipley in his 1918 study of the distribution of the globular clusters. In the Equatorial coordinate system they are: RA 17h45m40.04s, Dec -29° 00' 28.1" (J2000 epoch).

The complex astronomical radio source Sagittarius A appears to be located almost exactly at the Galactic Center, and contains an intense compact radio source, Sagittarius A*, which coincides with a super massive black hole at the center of our Galaxy. Accretion of gas onto the black hole, probably involving a disk around it, would release energy to power the radio source, itself much larger than the black hole. The latter is too small to see with present instruments.

Our bodies receive-Sunlight Healing

The human race evolved under the sun and for thousands of years lived in close harmony with its heat and light.The infrared rays originated from the sun are useful in the treatment of neuralgia, neuritis, arthritis, and sinusitis. In treatment of pains, heat plays an effective role. Warmth keeps our body energetic. It also keeps the skin smooth and protected. Plants get food from the sun in the photosynthesis process. The foods we get from plants stored the solar energy in it. Our bodies receive the solar energy from the food in the form of fats, carbohydrates, and proteins. The ultraviolet rays are antiseptic in nature. It is capable of killing bacteria, viruses, fungi, yeasts, moulds, and mites in air, water and on surfaces. It also kills germs on our skin. For all types of skin diseases, Sunlight is a very useful treatment.

When ultraviolet rays from the sun comes in contact with ergosterol, a fluid found just under the skin, they convert it to vitamin `D`, which is absorbed into the bloodstream. Ten minutes of daily exposure to sunlight will supply us with the entire vitamin `D` that we need. The principal function of vitamin `D` is to promote calcium absorption in the gut and calcium transfer across cell membranes. This contributes to strong bones and a contented nervous system. Ultraviolet light converts cholesterol in the skin to vitamin `D`. This vitamin is essential for the proper handling of calcium in the body and thus in the prevention of rickets and adult osteomalacia. Interestingly, people cant overdose on natural vitamin `D` from the sun, even with day-after-day exposure, whereas synthetic vitamin `D` supplements can easily cause vitamin `D` toxicity.

Sunlight plays an effective role in regulating almost all our bodily processes. Sunlight has been shown to increase our sense of well-being and to improve sleep. Ultraviolet light coming into our eyes stimulate the pineal gland, which helps to regulate our Circadian Rhythm. It has been said, "Dark nights and bright days will help keep the hormones in the body functioning properly.

Sloan Digital Sky Survey

The Sloan Digital Sky Survey or SDSS is a major multi-filter imaging and spectroscopic red shift survey using a dedicated 2.5-m wide-angle optical telescope at Apache Point Observatory in New Mexico. The project was named after the Alfred P. Sloan Foundation.

The surveys were begun in 2000, and aims to map 25% of the sky and obtain observations on around 100 million objects and spectra for 1 million objects. The main galaxy sample has a median redshift of 0.1; there are redshifts for luminous red galaxies as far as z=0.4, for quasars as far as z=5; and the imaging survey has been involved in the detection of quasars beyond a redshift 6.

In the year 2006 the survey entered a new phase, the SDSS-II, by extending the observations to explore the structure and stellar makeup of the Milky Way, the SEGUE and the Sloan Supernova Survey, which watches after supernova Ia events to measure the distances to far objects.

The SDSS telescope uses the drift scanning technique, which lets the telescope fix and makes use of the earth's rotation to record small stripes of the sky. The image of the stars in the focal plane drifts along the CCD chip, instead of staying fixed as in tracked telescopes. This method allows consistent astrometry over the widest possible field and precision remains unaffected by telescope tracking errors. The disadvantages are minor distortion effects and the CCD has to be written and read in the same time.