THE UNIVERSE

The Universe is everything -- that is all energy, matter, and space.

Cosmology is the study of the structure and evolution of the entire universe.  The theory of the origin of the universe that is presently accepted by most astronomers is what is called the "BIG BANG THEORY".  The Big Bang theory of the Universe states that the known Universe was concentrated in a massive glob of extremely dense matter that exploded approximately 15 billion years ago.  It is widely accepted for three reasons:

1.    Astronomers observe galaxies that show a shift in their spectrum lines towards the low frequency (red) end of the electromagnet spectrum.  This means that they are all moving away, which supposes that they all started from one point.

2.    They detect a cosmic background radiation coming from space from all directions, referred to as 3-K cosmic microwave background.

3.    They observe a mass ratio of hydrogen to helium of 3 to 1 in stars and interstellar mater as specified by the Big Bang concept.

For more information of the Big Bang, click below:

 Big Bang

For origins of the Universe click below

 Origins of the Universe

How old is the Universe?  The red shift indicates an expanding Universe.  If we can determine the distance to the most distant galaxy, and the rate at which the Universe is expanding, then we can determine the age of the Universe.   The recessional velocity is given by Hubble's law.  V = Hd where V is the velocity, H is Hubble's constant, and d is the distance.  Hubble's constant varies from 50 to 100, with the lower value yielding a larger age of the Universe.  For details of Edwin Hubble,  click below.

          Edwin Hubble

For problems to calculate the age of the Universe, click below.

 Age of the Universe

Where did the Big Bang take place?  This question has no meaning, because at the moment of the explosion the makeup of the Big Bang was the entire Universe.  Space expands with time and forms the Universe.  So time and space do not exist outside the Universe.  Is the Universe flat?  Click below to find out.

 Flat Universe

What is the origin of all matter and radiation in the Universe? They came from nothing.  At the beginning, space and time did not exist.  Thus expanded violently creating space and time.  Some other mysteries of the Universe are Dark matter and Quasars.  Please click below:

 Mysteries of the Universe

Edge of Space: Mystery Clouds Glow Blue

They're thin, wispy, and shiny. They glow an unmistakable shade of electric blue. Clearly visible to the astronauts on the
International Space Station, the mysterious clouds float on the edge of space in the same region where the space shuttle Columbia broke up. What are they?

The official name for these high-altitude ice clouds is "noctilucent clouds" or "night-shining clouds." Some even speculate they may have contributed to the Columbia disaster. Others think they are seeded by space dust, while still others suspect they're a sign of global warming. Whatever they are, they're growing in abundanc and are a great puzzle to scientists, reports ABCNews.com and Space.com.

They are visible from Earth only in the summer months, so right now they can be seen in the Southern Hemisphere. "We've seen definite changes," admitted John Olivero, a professor of physical science at Embry-Riddle Aeronautical University in Daytona Beach, Fla., to ABCNews.com reporter Amanda Onion. "It appears the particles that make up the clouds have gotten slightly bigger with time, and it appears the clouds are now visible further away from the poles than they have been before."

The only other reported sighting of such clouds was more than a century ago in 1883 when Krakatoa, an island volcano in Indonesia, erupted. The ash spewed some 50 miles into the air and anchored water vapor at high altitudes. The vapor condensed to ice, and the blue clouds were formed. In addition to enjoying magnificent sunsets, Indonesians who stayed up late enough reported seeing the shimmering, blue clouds. Long after the sunsets returned to normal night-shining clouds were still visible. "It's puzzling," Gary Thomas, a professor at the University of Colorado, told Space.com reporter Tony Phillips. "Noctilucent clouds have not only persisted, but also spread."

A volcano eruption caused them in 1883. What has caused them to appear now? Scientists are stumped. They're up too high--some 30 to 60 miles above the Earth--to reach them by weather balloon, but they're too close to our planet for an orbiting satellite to check it out. There are theories. Global warming and the effect of greenhouse gasses on the mesosphere is the most popular one.

Even the space shuttle Columbia astronauts reported seeing them over the Southern Hemisphere. Because so little is understood about the night-shining clouds, some are wondering if they might have played a role in the Columbia disaster. Others dismiss that since Columbia broke up in the Northern Hemisphere, far away from the clouds.

All these questions may be answered in 2006 when NASA launches a small satellite that will take wide angle photographs of the noctilucent clouds, measure their temperatures and chemicals, and more. Until then, enjoy the view.

Earth Like Planet Found

An artist's rendition shows a newly discovered planet as a rocky, geologically active world glowing in the light of its parent star, Gliese 876.
 
'Rocky' Earth-Like Planet Discovered

It May Be First Such Body Scientists Have Found Outside Solar System

By Guy Gugliotta

 

Washington Post Staff Writer
Tuesday, June 14, 2005; Page A03

Astronomers said yesterday they have discovered what could be the first "rocky" Earth-like planet found outside the solar system. It is a lifeless, oven-like world about 7 1/2 times the size of Earth, orbiting a small star in the constellation Aquarius.

The team detected the new "extra-solar" planet by observing a tiny wobble induced in the star by the planet's gravity. The team made more than 150 observations over three years with precision measuring instruments before announcing its findings.

 


An artist's rendition shows a newly discovered planet as a rocky, geologically active world glowing in the light of its parent star, Gliese 876.

An artist's rendition shows a newly discovered planet as a rocky, geologically active world glowing in the light of its parent star, Gliese 876. (National Science Foundation Via Reuters)

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"This new technology has revealed the most terrestrial planet ever found," said team leader Geoffrey W. Marcy, an astronomer at the University of California at Berkeley. "For the first time, we are finding our planetary kin among the stars."

Paul Butler of the Carnegie Institution in Washington said he, Marcy and other team members began close observations of the star Gliese 876 several years ago. Gliese 876 is 15 light-years from Earth, an "M-dwarf" star about one-third the size of the sun. M-dwarves are the most common stars in the galaxy.

In 1998, Marcy and Butler reported detecting a "gas giant" planet about twice the size of Jupiter orbiting Gliese 876. Three years later, they reported a second gas giant about half the size of Jupiter. Astronomers do not "see" extra-solar planets; they deduce their presence by measuring the wobble.

The two large planets at Gliese 876 "dance in resonance," Butler said during a telephone news conference from the National Science Foundation. As they studied this interaction, "there was a clear signal of a third planet," he added. The foundation funded part of the research.

Over time, the team deduced that the third planet was less than half the size of any previously detected extra-solar planet, and thus was probably "rocky," or "terrestrial," to distinguish it from the Jupiter-like giants that have enough gravity to retain a massive gas envelope. Improvements in the instruments at Hawaii's W.M. Keck Observatory have enabled the team to detect smaller and smaller wobbles in stars -- signaling the presence of smaller planets.

"Over the years, we've announced the discoveries of 107 extra-solar planets, and we consider this the most exciting," Marcy said. So extraordinary was it, he added, that it became impossible to keep their work secret, so the team decided to announce the find. The research has been submitted for publication to the Astrophysical Journal.

While they had detected "the most Earth-like world ever discovered," team member Jack Lissauer said, "it's a very unearthly world." Lissauer, of NASA's Ames Research Center, said the planet is about 7 1/2 times the size of Earth and only 2 million miles from Gliese 876. It zoomed around the star in an orbit that lasted just 1.94 days.

"The surface of the planet is very warm -- between 400 and 700 degrees Fahrenheit," Marcy said, making it untenable for life. It has no solar system analogue, falling in size between Earth, the largest of the rocky planets, and Uranus, the smallest of the gas giants.

Still, the new research "demonstrates that current instruments and telescopes can spot almost Earth-like objects," said astronomer Kevin L. Luhman of the Harvard-Smithsonian Center for Astrophysics. "This is only the tip of the iceberg."

Since scientists began hunting for extra-solar planets about a decade ago, they have found more than 150. The overwhelming majority of them are Jupiter-like giants close to their host stars, enabling them to impart a significant wobble with relative frequency.

"But there's this huge range of sizes and distances that we haven't seen yet, and with the upgrades at Keck, this team is probably going to find a large number of them," Luhman said in a telephone interview. "They're going to have to go back and do the same stars all over again. But I bet they won't mind that."

Planet Candidate 'Xena' Has a Moon

Reuters
Monday, October 3, 2005; Page A02

Xena, the possible 10th planet in our solar system, has its own moon, a dim little satellite called Gabrielle, its discoverers reported.

Astronomers who reported Xena's discovery in July said they detected Gabrielle on Sept. 10 using the Keck Observatory on Mauna Kea in Hawaii. Their findings are to be submitted to the Astrophysical Journal Letters today.

 

Xena, known formally as 2003 UB313 but nicknamed for the warrior princess of television fame, and Gabrielle orbit the sun out beyond Pluto in a band known as the Kuiper Belt, a swath that is home to comets, asteroids and other space rocks.

The International Astronomical Union, which makes the decision on what is a planet, considers Xena a trans-Neptunian object, meaning its orbit crosses that of Neptune, just as Pluto's does. Many astronomers question Pluto's planetary status, too. But Xena's discovery, and its size, have prompted the union to rethink the definition of a planet.


 

Dark Matter

 Dark Matter

Quasistellar Radio Sources

 Quasars


 
 
 

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