Bintang 3 generasi Ditemui

1.5.09

Bintang 3 generasi Ditemui

Penemuan terbaru "bintang 3 generasi" (Globular Cluster NGC 2808) oleh teleskop angkasa lepas Hubble telah berjaya merungkai satu lagi misteri cakerawala dan sekaligus menghapuskan teori bahawa bintang di dalam sesuatu sistem terbentuk pada tempoh waktu yang sama. Penemuan terkini ini juga telah menguatkan lagi bahawa cakerawala ini "hidup" dan sentiasa berkembang mengikut kadar yang belum diketahui manusia.

kumpulan Globular Cluster NGC 2808 yang berusia sekitar 12.5 billion tahun dan merupakan sistem kumpulan bintang terbesar di cakerawala

Image: NASA/ESA/A Sarajedini (Uni.Of Florida)/G Piotto (Uni.Of Padua)

Pakar-pakar astronomi, dengan bantuan Advance Camera for Surveys (ACS) yang terdapat pada teleskop Hubble, telah berjaya mengukur warna dan kecerahan bintang-bintang di dalam cluster berkenaan. Analisa yang dilakukan mendapati, siri bintang 3 generasi ini lahir sekitar 200 juta tahun lampau, dan terletak di dalam satu sistem besar yang berusia sekitar 12.5 billion tahun.

NGC 2808, dianggarkan mengandungi lebih sejuta bintang dan dikatakan antara sistem bintang yang terbesar di cakerawala yang berjaya dikenalpasti setakat ini.

Bagaimana sistem ini mempunyai 3 generasi bintang di dalam satu sistem yang sama?
Pakar-pakar astronomi berpendapat, kombinasi daya graviti antara jutaan bintang-bintang di dalam sistem ini adalah terlalu kuat, sehingga mampu "memegang" semua unsur-unsur gas (seperti helium yang terhasil daripada letusan-letusan bintang yang mati di dalam sistem ini sendiri) yang diperlukan utk kelahiran sebuah bintang baru.

3 Generasi bintang di Globular Cluster NGC 2808

30.4.09

Ghostly Ring of Dark Matter! will Milky Way have one?

A distant galaxy cluster has yielded tantalising evidence of dark matter in the form of a gigantic ring that surrounds the clusters.

Although dark matter canot be see directly with our naked eyes, its present can be detect because its gravity bends and magnifies the light coming from more distant objects - a phenomenon known as gravitational lensing. By measuring the amount by which the more distant lights has been "lensed" and distorted, the team os astronomers using the Hubble Space Telescope were able to infer how much dark matter were present. they found it was in a ring around the cluster ZwC10024+1652, five billion light years away.

A composition image of the galaxy cluster ZwC10024+1652 with the inferred invisible dark matter added as the blue ring

Image: NASA/ESA/M J Jee and H Ford (John Hopkins University)

Curious about the ring?
Well, the curious ring shape can be explained by the collision between this cluster and another smaller cluster which happened about 2 billion years ago. This is the second example of dark matter being found around galaxy clusters. The first instance was the Bullet Cluster, found in October 2006.

Our Milky Way galaxy also in future, as predicted by astronomers will collide with Andromeda, which located about 2 billion light years from us today. The Andromeda is move toward us, with average speed of 500,000 km/s. And, if its really happend, it will be the end of both galaxy, and soon, a new galaxy will slowly born from the collision.

The Sun Approaching Solar Maximum

Helium gas caught in the sun's atmosphere may be responsible for the enormous solar explosions known as Coronal Mass Ejections (CMEs). Scientist from the Loas Alamos National Lab, used NASA's Wind spacecraft to make over 2.5 million measurements of the Sun over a decade of observation. It is believe that heliumgas builds up in the solar atmosphere, the corona. yet the solar wind, a constant stream of charged particles emanating from the sun isn't strong enough to completely eject the helium into space so it gradually accumulates until it is violently thrown off in a spectacular CME.

The Solar-Observing SOHO spacecraft.

The discovery of oscillations in the Sun provides a way to study the Sun's insides.

Image: SMM (IAC)

CMEs are some of the most violent and powerfull explosions on the Sun and, although they are not well understood, they seem to greatly affect solar wind speeds. Observations of these explosions show that the amounts of helium present in their ejections are around 5-10 times the abundances seen in the normal solar wind that is expelled continuously from the Sun.

But, scientist don't yet understand a most basic aspect of the solar wind: how exactly does material in the solar corona accelarate to the solar wind speeds of between 960,000 and 1.6 million kilometres per hour???

Scientists are also uncovering more about the very centre of the Sun after 30 years searching for elusive oscillations deep within the Sun. Now, new observations with the Global Oscillation at Low Frequency (GOLF) instrument in the Solar and Heliospheric Observatory (SOHO) may ahve detected the "telltale" ripples created by collisions between dense gas and gaseous material falling deeper into the Sun. These ripples, known as "g-modes", can tell us a great deal about the solar interior and the Sun's core. Also imprinted on these oscillations is information about the conditions in which the Sun formed and the rotation of the ancient cloud of gas that spawned it.

Below are  series pix of the Sun's, from the Solar and Heliospheric Observatory (SOHO), Extreme Ultraviolet Imaging Telescope. Thanks to my great buddy, Ezza from space agency, for sharing this superb pics with me...

The Sun in early 1990s

Image: SOHO - Extreme Ultraviolet Imaging Telescope

Image of the Sun in summer 2000

Image: SOHO - Extreme Ultraviolet Imaging Telescope

Image of the Sun in January 2009

Image: SOHO - Extreme Ultraviolet Imaging Telescope

The Sun's activities are so active...and will be more active within this few years. It is belive that the Sun will reach it solar activity in the year 2012, causing a huge magnetic storm in a history of mankind.

EMERGENCY ALERT NOW ON STAGE 5

Guys....

The World Health Organization (WHO) has raised the swine flu pandemic alert level to PHASE 5 - just one step below the highest level. The decision comes as the number of countries with confirmed cases rises to at least 10, with 1 death in the United States of America. 

The increase to level 5 indicates that there is sustained human-to-human transmission in communities in different geographical locations.

29.4.09

Nuffnang; Star Trek Movie contest

Nuffnang; Star Trek Movie contest

Star Trek...The Star Trek is a science fiction television series created by Gene Roddenberry that aired from September 8, 1966 to September 2, 1969. Though the original series was titled simply Star Trek, it has acquired the retronym Star Trek: The Original Series (ST:TOS or TOS) to distinguish it from the spinoffs that followed, and from the Star Trek universe or franchise they comprise. Set in the 23rd century, the original Star Trek follows the adventures of the starship Enterprise and its crew, led by Captain James T. Kirk (William Shatner), his First Officer Mr. Spock (Leonard Nimoy), and his Chief Medical Officer Leonard McCoy (DeForest Kelley). William Shatner's voice-over introduction during each episode's opening credits stated the starship's purpose...

Cast:

John Cho - Hikaru Sulu

Ben Cross - Sarek

Bruce Greenwood - Capt. Christopher Pike

Simon Pegg - Scotty

Chris Pine - James T. Kirk

Zachary Quinto - Spock

Winona Ryder - Amanda Grayson

Zoe Saldana - Nyota Uhura

Karl Urban - Dr. Leonard "Bones" McCoy

Anton Yelchin - Pavel Chekov

Eric Bana - Nero

Leonard Nimoy - Old Spock

I wanna watch the movie because, I'M A DIE HARD FAN OF STAR TREK....i do have all 7 season of Star Trek series and fell in love with Capt Jonathan Archer, Capt. Katherine Janeway and lotta others...hahaha. its a must die movie for me, as i've spent most of my free time wathing all the 7 seasons again and again.....

My Priceless Star Trek Collections

so guys...what are you waiting for

CATCH STAR TREK ON CINEMA ON MAY 7

H1N1 (SWINE FLU) EMERGENCY ALERT - LEVEL 4

Malaysians....

Do alert that the swine flu (H1N1) virus are suspected to arrived in our neighbour countries, Singapore , Thailand and Indonesia. 

The World health organization (WHO) raised the worlwide pandemic alert level to PHASE 4. A Phase 4 alert is characterized by confirmed person-to-person spread of a new influenza virus able to cause “community-level” outbreaks.” The increase in the pandemic alert phase indicates that the likelihood of a pandemic has increased.

What you can do to stay healthy??
please....

1. Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
2. Wash your hands often with soap and water, especially after you cough or sneeze. Alcohol-based hands cleaners are also effective.
3. Avoid touching your eyes, nose or mouth. Germs spread that way.

Avoid close contact with sick people. Influenza is thought to spread mainly person-to-person through coughing or sneezing of infected people.  If you get sick, MOH recommends that you stay home from work or school and limit contact with others to keep from infecting them.

28.4.09

Eta Aquarids Meteor Shower on May 5 & 6

The Eta Aquarids are a light shower, usually producing about 10 meteors per hour at their peak. The shower's peak will occur on May 5 & 6, however viewing should be good on any morning from May 4 - 7. This year, a waxing gibbous moon will hide all but the brightest meteors. The radiant point for this shower will be in the constellation Aquarius. Best viewing is usually to the east after midnight.

Location of the Eta Aquarids
For Northern Hemisphere Observers

Location of the Eta Aquarids
For Southern Hemisphere Observers

The eta Aquarids are flakes of dust from Halley's Comet, which last visited Earth in 1986. Although the comet is now far away, beyond the orbit of Uranus, it left behind a stream of dust. Earth passes through the stream twice a year in May and October. In May we have the eta Aquarid meteor shower, in October the Orionids. Both are caused by Halley's Comet.

The eta Aquarids are named after a 4th-magnitude star in the constellation Aquarius. The star has nothing to do with the meteor shower except that, coincidentally, meteors appear to emerge from a point nearby. Eta Aquarii is 156 light years from Earth and 44 times more luminous than the Sun. Eta Aquarid meteoroids hit Earth's atmosphere traveling 66 km/s.

So, dont forget to look east before sunrise on May 5 & 6 (><)

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