Jika anda ternampak muka saya tengah TT (Teh Tarik) ni, bermakna anda telah selamat mengharungi 3 hari bumi tak jadi bergelap, dan tarikh 21hb Dis yang penuh tragis dan huru-hara (kononlah).
Nak ceritanya, Falak Online telah pun berpindah rumah. Bermula sekarang silalah kemaskini link ke WWW.FALAKONLINE.NET , tak perlulah letak apa-apa selepas tu, kerana ia akan redirect ke muka hadapan BARU yang sepatutnya.
Laman lama (yang anda lihat sekarang ni), InsyaAllah akan kekal untuk beberapa bulan mendatang. Ia akan menyenaraikan KESEMUA artikel lama saya di FO, bagi rujukan anda semua. Maka, kalau anda nak masih nak marah-marah kat saya berkenaan artikel "3 hari bergelap tu" , masih boleh berbuat demikian, saya terima dengan hati terbuka! :-)
Apa pun, InsyaAllah 2013 mendatang akan terdapat beberapa pembaharuan yang saya dan rakan-rakan Personaliti Astronomi lain usahakan, demi kemajuan bidang Astronomi di Malaysia.
Jom dan Selamat Datang Ke Tahun Baru 2013.
Jemput masuk ---> WWW.FALAKONLINE.NET
Astronomers have come upon the tantalizing signal from some of the universe’s first stars.
The early universe was vastly different from the one we experience today. The elements we’re familiar with from everyday life didn’t exist — there was no carbon, no oxygen, no silicon. Instead, simple hydrogen and helium pervaded the primordial darkness, along with trace amounts of lithium and beryllium.
The first stars were vastly different too, born more than 13 billion years ago into swirling clouds of dark matter and pristine gas. With no heavier elements to cool collapsing gas clumps, the first generation of stars, known to astronomers as Population III stars, would have grown to giant size (at least 60 and maybe up to 300 times the mass of the Sun) before they could turn on fusion in their cores. They would have been responsible for churning out the heavier elements that shaped the evolution of second-generation stars and the galaxies they lived in, and they might even have ended their lives in furious explosions.
But until now, this first, vital generation of stars has been largely hypothetical. Now David Sobral (University of Lisbon, Portugal, and Leiden Observatory, The Netherlands) and colleagues have reported in the Astrophysical Journal a never-before-seen glimpse into first-generation star formation.Finding the First Stars
The discovery came as part of a larger survey conducted with the Subaru telescope on Mauna Kea, which picked out faraway galaxies by their Lyman-alpha lines, a spectral line associated with ionized hydrogen. The universe’s expansion has stretched these galaxies’ ultraviolet spectral line into Subaru’s near-infrared range.
Sobral’s team followed up on two of the brightest Lyman-alpha-emitting galaxies, dubbed MASOSA and CR7, observing them with the Very Large Telescope in Chile and the Keck II telescope in Hawai‘i. The spectrum of CR7, which spanned from near-infrared to ultraviolet wavelengths, showed exactly two emission lines: the Lyman-alpha line from ionized hydrogen and another emission line from ionized helium.
“If this is Population III star formation, then that is very exciting,” says Jonathan Tan (University of Florida). “It would be the first example of such a process.”Cautionary Tales
But, Tan cautions, though the detection of the helium spectral lines is strong enough, he’s not convinced it points exclusively to first-generation stars. He thinks second-generation stars, albeit ones really poor in heavier elements, might also be able to produce the observed signal.
Even if these stars really are unpolluted, first-generation stars, follow-up Hubble Space Telescope images show that they are not alone. Two red clumps of second-generation stars lie 16,000-some light-years away from the bluer clump at the galaxy’s center. The red clumps irradiate the blue clump, altering its star-formation chemistry.
It’s not yet clear why one part of the galaxy would already be on the second generation of star formation while another part is just getting started on the first. It could be that we are witnessing a wave of star formation sweep over the galaxy. But in any case, the presence of other stars means that any first stars within the blue clump aren’t quite the first generation.The Holy Grail
The real holy grail in this field, Tan says, is to find those stars born in true primordial darkness, free not just from the pollution of heavier elements but from light itself. “The James Webb Space Telescope is probably needed for this,” he adds, “and even then, I’m not certain it will be able to do it.”
Learn more about the first stars and other oddities in our special issue, Astronomy's 60 Greatest Mysteries.
Here’s a taste of what New Horizons hopes to resolve when it passes by Pluto next Tuesday, July 14th.
Scientists compiled this map of Pluto’s equator from images taken between June 27th and July 3rd by the New Horizons spacecraft’s Long Range Reconnaissance Imager and the Ralph instrument. That was just before a computer glitch sent the spacecraft into safe mode for three days, but New Horizons is now back up and running — and safe from any further such glitches as it continues its historic flyby.
Even though the composite image (below) is fuzzy, scientists have identified a few major features, such as “The Whale,” the dark region to the left that’s about 1,860 miles (3,000 kilometers) across, and four mysterious dark spots to the right. The bright region in the middle might come from reflective frost made of methane, nitrogen, or carbon monoxide. But perhaps most puzzling is that the features all hug the dwarf planet’s equator.
This map gives a taste of what’s to come. Though scientists may already be considering ideas to explain these features, any fully formed theories will wait for July 14th’s flyby, which will show features at a resolution of 100 meters per pixel.
Pluto's discovery is a fascinating story in its own right, an inspiring story captured in David Levy's book Clyde Tombaugh: Discoverer of Pluto.
Comet C/2014 Q1 PanSTARRS has been skirting the northern horizon since mid-June. Now it's ready to dip Down Under, where it may be visible with the naked eye in evening twilight.
I feel a bit sheepish touting this comet's horn for northern hemisphere skywatchers because it presents a great challenge for the brief time it may still be visible. But it's bright! Having just passed perihelion on July 6, the comet's current magnitude is +4. We'd all spring into action if Q1 PanSTARRS were well up at sundown. Unfortunately, it grazes the treetops and quickly vanishes below the horizon.
For stargazers at latitude 40°–45° north, the comet never climbs higher than 1°–3° above the northwestern horizon an hour after sunset and sets soon after. That's what I call cutting it close! Further north it rises a titch higher, but the crazy-long twilights at higher latitudes will likely negate any altitude advantage. If you can find a sky that's haze-free down to the western horizon, you still have the remainder of this week to attempt C/2014 Q1.
Observers Down Under fair much better. Viewed from mid-southern latitudes, Q1 PanSTARRS quickly climbs into the western winter sky, trekking from Cancer into Leo while passing Venus and Jupiter. By July 15, it will stand some 7° high near the end of evening twilight and likely be visible with the naked eye from dark skies.
Discovered in August 2014 by the Panoramic Survey Telescope & Rapid Response System (Pan-STARRS) survey atop Mt. Haleakala, expectations ran high that Q1 might swell to magnitude +3 with a long, bright tail during July and early August around the time of perihelion. Brightness-wise, that wasn't far off the mark, but it's unclear just how long a tail we might see. The coming weeks will tell.
On July 18th, watch for the thin crescent Moon and comet to pair up some 2° apart. According to Seiichi Yoshida, who maintains the excellent Weekly Information About Bright Comets site, C/2014 Q1 could do magnitude +5.5 or a bit better on that date. Together they should make a wonderful sight in binoculars and a pretty composition for the camera. The comet comes closest to Earth a day later at 109.7 million miles (176.6 million km).
A handful of dedicated comet watchers spied Q1 PanSTARRS as it transitioned from the southern sky to the northern in mid-June low in morning twilight. Alan Hale (co-discoverer of Comet Hale-Bopp) caught it on June 14 at 8th magnitude with a strongly-condensed coma.
Once Q1 PanSTARRS moves on, it'll be slim pickings for bright comets for northern hemisphere observers until C/2013 US10 Catalina leaps into the morning sky in mid-November. In the meantime, we can stock up on hand warmers and winter clothing.
If stargazing is part of your summer vacation plans — and for your sake I certainly hope it is — consider picking up one of our new fleece jackets.
These black jackets, embroidered with the classic Sky & Telescope logo, will help you meet that first rule of dressing for the cold: trapping layers of warm air near your body. As we all know, certain summer nights can become quite chilly, particularly in the hours before dawn — the night’s coldest. Be prepared for those clear, cold nights!
The jacket is made of cozy fleece, and it has pockets both outside (zippered) and in (open-top). Keep your hands warm in the outer ones, and store your favorite snack, a water bottle, or an extra eyepiece in the inner pocket. You can also cinch the bottom of the jacket with an elastic pull-string to keep the heat in.
Available in men’s L and XL, and women’s S, M, L, and XL. If the jacket proves popular among our readers, we’ll order more, including more sizes, and we’ll make it a regular item in Shop at Sky. But right now, quantities are limited, so act now!
The post Venus and Jupiter Conjunction – view from the Philippines appeared first on Sky & Telescope.
Amit Complex, Chinchwad Pune 411033
PCMC, Maharashtra 411033
Science and Astronomy society in Pune, India which works at grass root level for science popularization and also has recently established a research division for working on energy resources for future. We conduct public/private star gazing programs, shows and also run memberships for all.
The post The two planets playing among the fireworks. Venus and Jupiter conjunction, July 2, 2015. appeared first on Sky & Telescope.
The post Venus and Jupiter conjunction, July 2, 2015. The two planets playing among the fireworks. appeared first on Sky & Telescope.
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