PEACEFUL NIGHT IN ABU DHABI

Even with the high humidity that struck the night of Abu Dhabi it will not stopped me from going out and set-up my camera to capture the peaceful view it brings.

Pictures are taken from Abu Dhabi Heritage Village and sea-side view of sky rocketing buildings.

The light, the ambiance, the water those are the ingredients that pushes me to go out at night.

Meet the Solar System's Dwarf Planets

by Mike Wall, SPACE.com Senior Writer

For three-quarters of a century, school kids learned that our solar system has nine planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto.

But things changed nearly five years ago today. On Aug. 24, 2006, the International Astronomical Union (IAU) struck Pluto from the list, demoting it to the newly created category of "dwarf planet." The move was spurred by the discovery of multiple large bodies orbiting even farther from the sun than distant Pluto — particularly an object called Eris, which appeared to be bigger than Pluto.

As a result, the IAU came up with a new definition of "planet": A body that circles the sun without being some other object's satellite, is large enough to be rounded by its own gravity (but not so big that it begins to undergo nuclear fusion, like a star) and has "cleared its neighborhood" of most other orbiting bodies.

Since Pluto shares orbital space with lots of other objects out in the Kuiper Belt — the ring of icy bodies beyond Neptune — it didn't make the cut. So Pluto was newly classified as a dwarf planet, which tend to be smaller than "true" planets and fall short on the "clearing your neighborhood" criterion.

Although hundreds, or perhaps thousands, more solar system bodies may eventually join the list, the IAU officially recognizes just five dwarf planets at the moment. Here's a brief tour of all five: Pluto, Eris, Haumea, Makemake and Ceres.

Pluto: The demoted former planet

Pluto was discovered by American Clyde Tombaugh in 1930, as part of a search for the mythical "Planet X" that was thought to be perturbing the orbit of Uranus.

The dwarf planet was initially believed to be at least the size of Earth, but astronomers now know that it's about 1,455 miles (2,352 kilometers) across — less than 20 percent as big as our planet. And Pluto is just 0.2 percent as massive as Earth.

Pluto has an extremely elliptical orbit that's not in the same plane as the eight official planets' orbits. On average, the dwarf planet cruises around the sun at a distance of 3.65 billion miles (5.87 billion km), taking 248 years to complete one circuit. 

Because it's so far from the sun, Pluto is one of the coldest places in the solar system, with surface temperatures hovering around minus 375 degrees Fahrenheit (minus 225 degrees Celsius).

Pluto has four known moons: Charon, Nix, Hydra and a newly discovered tiny satellite currently called P4 (its final name may end up being Cerberus). While Nix, Hydra and P4 are relatively small, Charon is about half as big as Pluto. Because of Charon's size, some astronomers regard Pluto and Charon as a double dwarf planet, or binary system.

While Pluto is tough to study because it's so far away, scientists think the dwarf planet is about 70 percent rock and 30 percent ice. Its surface is covered predominantly with nitrogen ice. The dwarf planet has a thin atmosphere — composed mainly of nitrogen, methane and carbon monoxide— that extends about 1,860 (3,000 km) into space.

Pluto will start coming into clearer focus in a few years' time. NASA's New Horizons probe is due to make a close flyby of the dwarf planet in July 2015, marking the first time a spacecraft has ever visited the frigid, faraway world.

Eris: The troublemaker

Caltech astronomer Mike Brown led the team that discovered Eris in 2005. The find spurred the IAU to strip Pluto of its planethood and create the "dwarf planet" category a year later.

That decision remains controversial to this day, making Eris' name quite fitting: Eris is the Greek goddess of discord and strife, who stirred up jealousy and envy among the goddesses, leading to the Trojan War. Eris' one known moon, Dysnomia, is named after the goddess' daughter, who served as the spirit of lawlessness.

Eris is virtually the same size as Pluto, but it's about 25 percent more massive, suggesting that Eris contains considerably more rock (and less ice) than its Kuiper Belt neighbor. However, the surfaces of the two dwarf planets appear to be similar, composed primarily of nitrogen ice.

Like Pluto, Eris has a highly elliptical orbit. But Eris is even more far-flung, orbiting the sun at an average distance of about 6.3 billion miles (10.1 billion km). It takes Eris 557 years to complete one lap around the sun.

Haumea: The oddball

Haumea, a Kuiper Belt denizen orbiting slightly beyond Pluto, was discovered by Brown and his team in late 2004. It's one of the weirdest objects in the solar system.

Haumea measures about 1,200 miles (1,931 km) across, making it nearly as wide as Pluto. But Haumea is just one-third as massive as Pluto, partly because it's not spherical. Rather, Haumea is shaped like a giant American football.

The dwarf planet also completes one full rotation in less than four hours, making it one of the fastest-spinning bodies in the solar system. This super-charged spin is responsible for Haumea's oblong shape, pushing the dwarf planet outward substantially at the equator.

Haumea, named after the Hawaiian goddess of childbirth, has two known moons, Hi'iaka and Namaka. The moons share their names with two of the goddess' daughters, who are deities in their own right.

Scientists recently discovered that 75 percent of Haumea's surface is covered with crystalline water ice, similar to the stuff found in your freezer. 

An energy source is generally required to maintain such organized, structured ice. Astronomers theorize that energy may come from radioactive elements inside Haumea, as well as heat generated by the tidal forces the dwarf planet and its moons exert on each other.

Haumea makes one complete lap around the sun every 283 years.

Mysterious Makemake

Brown's team also discovered Makemake, spotting the dwarf planet in 2005.

Astronomers aren't sure of Makemake's exact size, but the dwarf planet is thought to be about three-quarters as big as Pluto. It's therefore likely the third-largest dwarf planet, after Eris and Pluto.

Makemake orbits the sun from slightly farther away than Pluto, at an average distance of 4.26 billion miles (6.85 billion km), and completes an orbit every 310 years or so.

Makemake is the second-brightest Kuiper Belt object (after Pluto) and can be seen with a high-end amateur telescope, according to the IAU. Like Haumea, Makemake is named after a Polynesian deity — in this case, the creator of humanity and god of fertility in the pantheon of the Rapanui, the native people of Easter Island.

Like Pluto and Eris, Makemake appears to be a reddish color in the visible-light spectrum. Scientists think its surface is covered by a layer of frozen methane, and the distant world has no known moons.

This Hubble Space Telescope image shows Ceres, the most massive object in the asteroid belt, a region between Mars and Jupiter. Hubble images are helping astronomers plan for the Dawn spacecraft's visit to Ceres in 2015.

Ceres: King of the asteroid belt

Ceres is the only dwarf planet not found in the freezing cold, faraway Kuiper Belt. Rather, it orbits in the main asteroid belt between Mars and Jupiter, completing one lap around the sun every 4.6 years.

Ceres is by far the largest object in the asteroid belt, containing about one-third of the belt's mass. However, at 590 miles (950 km) across, it is the smallest known dwarf planet. It is named after the Roman goddess of the harvest and motherly love.

Because it's so much closer to Earth than the other dwarf planets, Ceres was discovered far earlier. Italian astronomer Giuseppe Piazzi spotted it first, on Jan. 1, 1801. For the next half-century, many astronomers regarded Ceres as a true planet.

That changed when it became apparent that Ceres was just one of many bodies hurtling through space in the asteroid belt. [The Seven Strangest Asteroids]

These days, most astronomers regard Ceres as a protoplanet, saying it likely would have continued growing into a full-fledged rocky planet like Earth or Mars if Jupiter hadn't shaken up the asteroid belt long ago.

Ceres is thought to be a complex, differentiated body harboring quite a bit of water. Scientists think it has a rocky core surrounded by a water-ice mantle, and its rocky surface may also sport some water ice. Some researchers believe an ocean of liquid water may slosh about beneath Ceres' surface.

Scientists and the world will get a much better look at Ceres less than four years from now. In February 2015, NASA's Dawn spacecraft — which is currently orbiting Vesta, the asteroid belt's second-largest resident — will arrive at Ceres to undertake a detailed study of the dwarf planet

Understanding Celestial Coordinates by Alan M. MacRobert

                                               from www.skyandtelescope.com

In this time exposure, stars circle the north celestial pole as Earth turns. The stars trace out arcs of constant declination, the sky equivalent of latitude. Bright Polaris, the North Star, lies within 1° of the north celestial pole — where Earth's axis intersects the celestial sphere.

© 2001 Edwin L. Aguirre & Imelda B. Joson

Newcomers to astronomy can get thrown for a loop when they first encounter declination and right ascension, the terms astronomers use to define coordinates in the sky. Why are the positions of stars that are light-years away in the depths of space stated in a system that's tied to latitude and longitude here on Earth?
The celestial coordinate system, which serves modern astronomy so well, is firmly grounded in the faulty world-view of the ancients. They believed the Earth was motionless and at the center of creation. The sky, they thought, was exactly what it looks like: a hollow hemisphere arching over the Earth like a great dome. The stars? "They're fireflies," explains Timón in The Lion King,"stuck to that big, uh, blue-black thing up there."

The Earth is at the center of the celestial sphere,an imaginary surface on which the planets, stars, and nebulae seem to be printed. On the celestial sphere, lines of right ascension and declinationare similar to longitude and latitude lines on Earth. When a telescope's right-ascension axis is lined up with the Earth's axis, as shown here, the telescope can turn on it to follow the rotating sky.

S&T / Steven Simpson

The celestial dome with its starry decorations had to be a complete celestial sphere, early skywatchers realized, because we never see a bottom rim as the dome tilts and rotates around the Earth once a day. Part of the celestial sphere is always setting behind the western horizon, while part is always rising in the east. At any time half of the celestial sphere is above the horizon, half below.
Even today this is how the cosmic setup actually looks. Never mind that we're on a moving dust mote orbiting a star in the fringe of a galaxy. In astronomy, appearances and reality are more different than in any other area of human experience. Perhaps for this reason, astronomers are quite comfortable living with both — as long as the two are kept in their proper relationship. The celestial sphere, with its infinitely large radius, appears to turn daily around our motionless Earth, from which we use telescopes to examine wonders painted on its inside surface.
From Earth to Sky
Whenever you want to specify a point on the surface of a sphere, you'll probably use what geometers call spherical coordinates. In the case of Earth, these are named latitude and longitude.
Imagine the lines of latitude and longitude ballooning outward from the Earth and printing themselves on the inside of the sky sphere, as shown at right. They are now called, respectively, declination and right ascension.

In this 175KB animated GIF photo sequence, a small refractor swings westward (toward decreasing right ascension), rotating about its polar axis while holding its declination fixed. It then moves south (decreasing declination) at a fixed right ascension.

S&T / Craig Michael Utter

Directly out from the Earth's equator, 0° latitude, is the celestial equator, 0° declination. If you stand on the Earth's equator, the celestial equator passes overhead. Stand on the North Pole, latitude 90° N, and overhead will be the north celestial pole,declination +90°.
At any other latitude — let's say Kansas City at 39° N — the corresponding declination line crosses your zenith: in this case declination +39°. (By custom, declinations north and south of the equator are called + and – rather than N and S.) This is the declination of the bright star Vega. So once a day, Vega passes overhead as seen from the latitude of Kansas City.
Lines of both right ascension and declination stay fixed with respect to the stars. That's why they can be permanently printed on star maps. (This does mean that the one-to-one connection between right ascension and longitude is broken the moment after you imagine the lines ballooning out from Earth and printing themselves on the sky; the two systems rotate with respect to each other.)

ARE YOU FAN OF E.T.

E.T.can call us back again.

A California institute plans to restart its listening device to track for intelligent life in space. Back in April, the Search for Extraterrestrial Intelligence (SETI) Institute was forced to shut down its $30-million radio telescope array, designed to hear potential signals from alien life forms, for lack of funds. But officials with the nonprofit institute in northern California’s Mountain View appealed for donations. This week, they said the total raised had surpassed their $200,000 goal. That was due to the generosity of more than 2,400 donors, including actress Jodie Foster and Apollo 8 astronaut Bill Anders, they said.

As a result, the institute said it expects to restart the telescope array in September and keep it running at least through the end of the year. The plan is still dependent upon the center receiving an unspecified amount of funds from the U.S. Air Force to track space debris that could damage satellites.

Thomas Pierson, chief executive of the SETI Institute, said he expects the nearly finalized deal with the Air Force will, combined with the private funds, allow the group’s Allen Telescope Array to again listen for space chatter.

“For those who are interested in understanding whether intelligent life might be out there elsewhere in our galaxy, the Allen Telescope Array and our SETI team doing the research is the best bet,” Pierson said.

The search for alien life is a scientific discipline currently underway by a small number of U.S. universities and groups in Australia, Argentina and Italy, Pierson said.

RADIO TELESCOPE ARRAY

The Allen Telescope Array is the first instrument designed from the ground-up, with the goal of listening for signals from extraterrestrial life, Pierson said.

It is named after Microsoft Corp co-founder Paul Allen, one of its chief benefactors, and consists of dozens of dish-like antennas operated as one large radio telescope.

Located in a remote area in the shadow of Lassen Peak, east of Redding, California, it began initial operations in 2007, according to the SETI Institute.

The array is part of the Hat Creek Radio Observatory, a facility of the University of California, Berkeley.

The SETI project was hit hard by recent federal government budget cuts and by cost savings at UC Berkeley.

Pierson said the 27-year-old SETI Institute, which aside from overseeing the telescope array also researches origins of life in extreme environments and conducts public education, had received two-thirds of its funding from government sources.

Now, the institute is in a “transition phase” as it seeks more private funds and ways to control costs in order to continue operating the telescope array beyond 2011, he said.

The array costs $1.5-million a year to run. Fortunately for the institute, it has high-profile advocates.

Oscar-winner Foster, who played an alien-seeking scientist in the 1997 film Contact, explained her support in a statement on a fund-raising website created for the array: “The Allen Telescope Array could turn science fiction into science fact, but only if it is actively searching the skies.”

WHAT A HUMID AND HAZY NIGHT

Abu Dhabi Astronomy class and a friend went out last night to have an actual meteor shower and star gazing activity but the weather didn't give a  favor. Too humid and the sky so hazy that we aren't able to see stars and so as with the meteor shower. Stayed long night by just looking at the beauty of the moon through Astromaster telescope plus the actual demonstration of telescope calibration and some star gazing tips.

In the future we plan to go back in the field to have a better activity. Thanks guys for the wonderful night.

THERE WAS TWO MOONS

 Twin moons in the night sky above Earth? It might have been reality about 4 billion years ago, a new model suggests the lunar farside highlands could have been created from a collision with a smaller companion moon in what scientists from the University of California, Santa Cruz are calling “the big splat.” The idea came from the observation that why the near and far sides of the Moon are so different these has long puzzled the planetary scientists. The near side is relatively low and flat, while the topography of the far side is high and mountainous, with a much thicker crust. We actually have a somewhat lopsided Moon.

The new study, published in the August 4 issue of Nature, builds on the “giant impact” model for the origin of the moon, in which a Mars-sized object collided with Earth early in the history of the solar system and ejected debris that coalesced to form the moon.

According to the new computer model, the second moon around Earth would have been about 1,200 kilometers (750 miles) wide and could have formed from the same collision. Later, the smaller moon fell back onto the bigger Moon and coated one side with an extra layer of solid crust tens of kilometers thick.

"Our model works well with models of the Moon-forming giant impact, which predict there should be massive debris left in orbit about the Earth, besides the Moon itself,” said Erik Asphaug, professor of Earth and planetary sciences at UC Santa Cruz. “It agrees with what is known about the dynamical stability of such a system, the timing of the cooling of the moon, and the ages of lunar rocks.”

Other computer models have suggested a companion moon, said Asphaug, who coauthored the paper with UCSC postdoctoral researcher Martin Jutzi.

A previous collision with a smaller companion could explain why the Moon's two sides look so different. Credit: Martin Jutzi and Erik Asphaug

Asphaug and Jutzi used computer simulations to study the dynamics of the collision between the Moon and a smaller companion, which was about one-thirtieth the mass of the “main” moon. They tracked the evolution and distribution of lunar material in its aftermath.

The impact between the two bodies would have been relatively slow, at about 8,000 kph (5,000 mph) which is slow enough for rocks not to melt and no impact crater to form. Instead, the rocks and crust from the smaller moon would have spread over and around the bigger moon.

“Of course, impact modelers try to explain everything with collisions. In this case, it requires an odd collision: being slow, it does not form a crater, but splats material onto one side,” Asphaug said. “It is something new to think about.”

He and Jutzi hypothesize that the companion moon was initially trapped at one of the gravitationally stable “Trojan points” sharing the Moon’s orbit, and became destabilized after the moon’s orbit had expanded far from Earth. “The collision could have happened anywhere on the Moon,” Jutzi said. “The final body is lopsided and would reorient so that one side faces Earth.”

The model may also explain variations in the composition of the moon’s crust, which is dominated on the near side by terrain comparatively rich in potassium, rare-earth elements, and phosphorus (KREEP). These elements, as well as uranium and thorium, are believed to have been concentrated in the magma ocean that remained as molten rock solidified under the moon’s thickening crust. In the simulations, the collision squishes this KREEP-rich layer onto the opposite hemisphere, setting the stage for the geology now seen on the near side of the moon.

While the model explains many things, the jury is still out among planetary scientists as to the full history of the Moon and what really happened. Scientists say the best way to figure out the Moon’s history is to get more data from lunar orbiting spacecraft and – even better – sample return missions or human missions to study the Moon.

Sources: UNIVERSE TODAY