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).

:-D

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

 

Astronomy

Seeing Signs of the First Stars?

Sky and Telescope - Thu, 09/07/2015 - 23:17

Astronomers have come upon the tantalizing signal from some of the universe’s first stars.

An artist's impression of faraway galaxy CR7, which lives at a redshift of 6.6 and contains a blue clump of pristine stars unpolluted with heavier elements. Two redder clumps of second-generation stars lie north and northeast of the galaxy in this image.ESO / M. Kornmesser

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

A false-color composite image shows CR7 in all its distant glory. Two of Hubble's ultraviolet filters are shown in blue and red, and the Lyman alpha line emission is shown in green. The redder clumps C and B lie roughly 16,000 light-years (5 kpc) north and northeast of bluer clump A in this image.

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.

The post Seeing Signs of the First Stars? appeared first on Sky & Telescope.

Categories: Astronomy

Glimpsing Pluto’s Curious Equator

Sky and Telescope - Thu, 09/07/2015 - 01:48

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 of Pluto, created from images (with resolutions of about 100 to 67 km per pixel) taken from June 27th to July 3rd, 2015, by the Long Range Reconnaissance Imager (LORRI) on New Horizons, was combined with lower-resolution color data from the spacecraft's Ralph instrument. The center of the map corresponds to the side of Pluto that will be seen close-up during New Horizons' July 14th flyby.
NASA / JHU-APL / Southwest Research Institute

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.

The post Glimpsing Pluto’s Curious Equator appeared first on Sky & Telescope.

Categories: Astronomy

C/2014 Q1 PanSTARRS — Next Naked-Eye Comet?

Sky and Telescope - Wed, 08/07/2015 - 19:09

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.

Comet C/2014 Q1 PanSTARRS photographed under extreme conditions just 10° from the Sun 45 minutes after sunset from Austria on July 4, 2015 with a 10-inch telescope. On July 6, it passed just 0.3 a.u. from the Sun. Here we see its strongly condensed coma and short tail.
Michael Jäger

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.

Comet Q1 PanSTARRS hugs the horizon for northern hemisphere observers and will be a difficult catch the next few nights. This map shows the sky facing west from Minneapolis, Minnesota (45° north), one hour after sunset on July 9 (10 p.m. CDT). Stars shown to mag. +6. Although the map seems to show the comet's altitude peaking around the 16th, it will actually be below the horizon at that time because of the seasonal drift of the stars. Click for large version and also see the chart at the end of the article.
Chris Marriott's SkyMap software

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.

Thomas Lehmann cycled five kilometers from his hometown of Weimar to a small hillock to capture this fleeting view of Comet C/2014 Q1 PanSTARRS in Gemini at dusk on July 6, 2015. He used a 300mm f/4 telephoto lens.
Thomas Lehmann

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.

Comet C/2014 Q1 PanSTARRS is now best seen from the southern hemisphere (Alice Springs, Australia here) during the winter months of July and August. On July 18 (shown here) the comet joins the crescent Moon, Jupiter, and Venus for a scenic gathering in the west at nightfall. Stars to magnitude +6. Click for large version.
Chris Marriott's SkyMap software

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.

Comet Q1 PanSTARRS was first seen around magnitude +11.5 by southern hemisphere observers in mid-spring. Before moving into the northern sky, it glowed around magnitude +10. It's presently 4th magnitude and expected to fade over the coming weeks as it becomes well-placed again for southern observers.
Seiichi Yoshida

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).

The two previous maps give you an idea of the comet's position in relation to the western horizon. Use this map to follow C/2014 Q1 PanSTARRS' progress through the end of August. Dates are shown for 0h Universal Time (UT). Click for a full-sized version.
Sky & Telescope

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.

The post C/2014 Q1 PanSTARRS — Next Naked-Eye Comet? appeared first on Sky & Telescope.

Categories: Astronomy

Get Fleeced!

Sky and Telescope - Wed, 08/07/2015 - 04:45

Peter Tyson and the Sky & Telescope fleece jacket
S&T: Sean Walker

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!

Sky & Telescope Fleece
S&T: Sean Walker

The post Get Fleeced! appeared first on Sky & Telescope.

Categories: Astronomy

Moon approaching Venus & Jupiter

Sky and Telescope - Tue, 07/07/2015 - 14:10
Categories: Astronomy

Venus ‘swallowed’ in!

Sky and Telescope - Tue, 07/07/2015 - 14:01

The post Venus ‘swallowed’ in! appeared first on Sky & Telescope.

Categories: Astronomy

The big two are really threatened

Sky and Telescope - Tue, 07/07/2015 - 04:13
Categories: Astronomy

Astrotrekers Group

Sky and Telescope - Mon, 06/07/2015 - 22:16
NAME

Astrotrekers Group

ADDRESS

Amit Complex, Chinchwad Pune 411033
PCMC, Maharashtra 411033
India

CONTACT

Shrikrishna Kulkarni

PHONE

912027358217

EMAIL

shrikrishna@astrotrekkers.com

URL

http://www.astrotrekkers.com

NUMBER OF MEMBERS

20

OTHER INFORMATION

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 Astrotrekers Group appeared first on Sky & Telescope.

Categories: Astronomy

M20 M8

Sky and Telescope - Mon, 06/07/2015 - 20:43

The post M20 M8 appeared first on Sky & Telescope.

Categories: Astronomy

Orion

Sky and Telescope - Mon, 06/07/2015 - 20:40

The post Orion appeared first on Sky & Telescope.

Categories: Astronomy

plympia

Sky and Telescope - Mon, 06/07/2015 - 19:29

The post plympia appeared first on Sky & Telescope.

Categories: Astronomy

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