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Stars

Helix Nebula (NASA-JPL) The Helix Nebula is a dead star about 700 light-years from Earth, which was the same type of star as our Sun. By looking at the Helix Nebula, we can observe the future of our Sun, which will suffer the same fate in about 5-billion years from now. Much of what we know about these nebulae has been accumulated by observations in both visible and infrared light. background-color:#ffc; background-color:#ffc; In recent years, the skies have been observered in a broad range of electro-magnetic wavelengths from low-frequency radio waves to ultra short x-ray wavelengths.

Stars, like living creatures, are born, grow, mature, and eventually die. Our Sun, for example, was born about 4.5-billion (~4.5 × 109) years ago and will explosively die in another 5-billion years.
One may wonder about the idea that our Sun will die; then, what happens?  Near the end of its life, our Sun will expand and cool. The expansion will envelop the Earth and the entire Solar System, just like The Helix Nebula (right). Our Solar system will be engulfed in a cloud of dust surrounding cool, rea remnant of our Sun. Sages tell us, "All are from the dust, and to dust all return."

The Cosmos

An evening stroll along a romantic beach or an adventurous climb to the top of a high mountain are good places to start a sojurn into the wonders of The Cosmos. Bright city lights obscure the astounding view of the sky on a clear night.
Objects, and in deed our entire universe, appears different in different wavelengths. Our human eyes can only see a very thin slice of what exists, but scientists use the most amazing telecscopes that see the universe at wavelengths of light far, far beyond human vision.
Visible against a black sky are millions of points of twinkling light, overlaid by both dark and bright clouds of dust. Beyond our Milky Way Galaxy, billions and billions more galaxies exist, each contianing billions or even trillions of stars. Very distant galaxies appear as tiny smudges of light that can be seen in their true form only with the most powerful of telescopes. Nebulae, i.e. stars and groups of stars embedded in clouds of dust, reveal some of the most artistic abstract forms found in the heavens.
The photo (above) of the southern sky was taken by Håkon Dahle, an astronomer with the Euro­pean Southern Observatory (ESO) in Chile, which is described as the world's most advanced ground-based observatory.

One might ask, "How old is the Universe?" The answer to that question has varied over the millennia as human scientific exploration continually adds to the richness of our understanding of our physical world. The scholarly disciplines of astronomy and astrophysics have respectively produced observations and theories that have indeed answered many questions, but much more must be learned before a completely confident answer to the age of the Universe can be resolved. Our present knowledge, however, suggests that "our" Universe, there may be other universes, is 13.82-billion years old, according to the European Space Agency

Within the same framework of knowledge, our Sun is about 5-billion years old, our Sun being a fairly common variety of star that is currently in its middle age of life;   yes, stars are born, grow old, and die. The age of the Earth has been established with a high degree of confidence at 4.5-billion years. Although our earthly existence has no brothers and sisters in our Solar System, we may have brothers and sisters in our galaxy, as well as in other galaxies and, perhaps, other universes.

Many of "today's" astronomic hot topics revolve around such exotic things as novae, supernovae, black holes, quasars, pulsars, binary stars, white-dwarf stars, red-giant stars, and neutron stars. These objects and many new forms of astronomic strangeness have contributed to human understanding of the cosmos.  If all of this astronomic stuff sounds a bit bizarre to any level-headed adult, we are in good company. The famous physicist, John Wheeler (1911–2008) said in 1972 at The New York Academy of Sciences, "This is all crazy." Though John Wheeler coined the phrase "black hole", which is an intense gravitational force that traps light, the idea of a massive "light trap" first appeared in the 18th century. Among Prof. Wheeler's virtues, according to some, was his ability to characterize a complicated idea in simple terms, thus, "black hole" to characterize "gravitational collapse".

To continue to explore the heavens,
  select a Destination from the dropdown menu at top.