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.
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Researchers identify titanium oxide as a potential molecule at work in exoplanet atmospheres.
The Earth’s ozone layer keeps the Sun from boiling all our planet’s living beings. Located near the bottom of the stratosphere, the layer of ozone molecules absorbs the Sun’s harmful (to us, anyway) ultraviolet radiation. Hot Jupiters may have an ozone-like layer too, and even though they probably can’t host life, that layer has Earth-like effects on their atmosphere. Finding a hot Jupiter version of the ozone molecule has posed a challenge, but now, researchers believe they might finally have detected that molecule.
A temperature inversion is an essential ingredient in any complex atmosphere. It occurs right between the troposphere (the layer up against a planet’s surface) and the stratosphere (the next layer above it). In the troposphere the warmest air is found at the ground level and the coolest at the top. In the stratosphere, however, it’s the exact opposite – cooler air at the bottom and warmer air at the top. The inversion is this switch in the relationship between altitude and temperature.
Certain molecules that live in the stratosphere, such as ozone, are what cause this relationship change. Ozone high in the atmosphere breaks apart as it absorbs the Sun’s radiation, heating the stratosphere. But lower down, ozone absorbs less radiation, so the temperature remains cooler. Other solar system planets utilize hydrocarbons (such as propane and methane) as their absorbing molecules.
Researchers have found signs of temperature inversions on exoplanets as well, most notably on hot Jupiters. These exoplanets orbit very close to their host stars, and thus are way too hot to allow ozone and hydrocarbons to carry out their absorbing duties – the molecules would simply boil away. As such, there must be another molecule at work, and a recent study conducted by Korey Haynes (NASA Goddard Space Flight Center) and colleagues has taken the first tentative steps toward identifying the culprit.
Using the Wide Field Camera 3 on the Hubble Space Telescope, the team found emission signatures for titanium oxide (TiO), a heavy-duty radiation absorber, on the exoplanet WASP-33b. Unlike ozone and hydrocarbons, TiO can remain in gas form even at excruciatingly high temperatures. On the other hand, TiO is a heavy molecule and some researchers doubted whether it could remain suspended so high in the atmosphere, as it would have to counter strong gravity and cohesion forces.
“This observation of WASP-33b is a tantalizing first step,” explains Laura Kreidberg (University of Chicago), “but additional observations of the planet will be needed to definitively reveal which molecules are responsible for the temperature structure.”References
Korey Haynes et al. “Spectroscopic Evidence for a Temperature Inversion in the Dayside Atmosphere of the Hot Jupiter WASP-33b.” Astrophysical Journal, May 06, 2015.
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Friday, June 19
The pair-up of Venus and Jupiter is becoming ever more eye-catching in the west at dusk, as they near their June 30th closest approach. This evening as twilight fades, look below them for the thin waxing crescent Moon, as shown here.
Saturday, June 20
The Moon, Jupiter, and Venus form a striking triangle in the west during and after dusk. Regulus and the Sickle of Leo watch over them from the upper left. Think photo opportunity!
Sunday, June 21
Now the Moon shines left of Regulus in the evening. Jupiter and Venus are farther lower right, as shown here.
Today is the longest day of the year in the Northern Hemisphere; the shortest in the Southern Hemisphere. The solstice is at 12:38 p.m. EDT (16:38 UT), marking the official start of northern summer (southern winter). Because the solstice time falls right between the nights before and after in the Eastern time zone, you can have two Midsummer's Night parties!
Monday, June 22
Saturn is the brightest point glowing in the south these evenings. The stars of upper Scorpius glitter below and lower left of it.
Tuesday, June 23
As night falls, look for the Big Dipper hanging straight down in the northwest. Its bottom two stars, the Pointers, point to the right toward modest Polaris, the handle-end of the Little Dipper. Most of the Little Dipper is very dim. This is the time of year when it floats straight upward from Polaris when nightfall is complete — like a helium balloon escaped from some June evening party.
Wednesday, June 24
The Summer Triangle looms high in the east after dark. Its top star is bright Vega. Deneb is the brightest star to Vega's lower left (by 2 or 3 fists at arm's length). Look for Altair a greater distance to Vega's lower right.
First-quarter Moon (exact at 7:02 a.m. EDT).
Thursday, June 25
Look for pale bluish Spica below the Moon this evening. Four-star Corvus is much farther below them and perhaps a bit right.
The brightest star shining very high above the Moon is Arcturus.
Friday, June 26
Venus and Jupiter, shining in the west as twilight fades, are now only 2.2° apart! That's about the width of your thumb held at arm's length. They point to fainter Regulus, twinkling to their upper left. Watch the two planets move closer together each evening until their appulse (closest approach) on Tuesday June 30th. That evening they'll be just 1/3° apart, seven times closer than they appear now!
In reality, they're not close together at all. Venus is 51 million miles from Earth this evening; Jupiter is eleven times farther at 561 million miles.
Saturday, June 27
Venus and Jupiter have closed to 1.7° from each other in the west at dusk.
In the southern sky, look for Saturn lower left of the gibbous Moon this evening. Scattered to the lower left of Saturn are the stars of Scorpius. The brightest of these is orange Antares.
Look low in the east-northeast about 45 minutes before sunrise tomorrow morning to catch Mercury, as shown below. Can you also see twinkly Aldebaran?
Want to become a better astronomer? Learn your way around the constellations. They're the key to locating everything fainter and deeper to hunt with binoculars or a telescope.
This is an outdoor nature hobby. For an easy-to-use constellation guide covering the whole evening sky, use the big monthly map in the center of each issue of Sky & Telescope, the essential guide to astronomy.
Once you get a telescope, to put it to good use you'll need a detailed, large-scale sky atlas (set of charts). The standards are the little Pocket Sky Atlas, which shows stars to magnitude 7.6; the larger and deeper Sky Atlas 2000.0 (stars to magnitude 8.5); and once you know your way around, the even larger Uranometria 2000.0 (stars to magnitude 9.75). And read how to use sky charts with a telescope.
You'll also want a good deep-sky guidebook, such as Sue French's Deep-Sky Wonders collection (which includes its own charts), Sky Atlas 2000.0 Companion by Strong and Sinnott, the bigger Night Sky Observer's Guide by Kepple and Sanner, or the beloved if dated Burnham's Celestial Handbook.
Can a computerized telescope replace charts? Not for beginners, I don't think, and not on mounts and tripods that are less than top-quality mechanically (meaning heavy and expensive). As Terence Dickinson and Alan Dyer say in their Backyard Astronomer's Guide, "A full appreciation of the universe cannot come without developing the skills to find things in the sky and understanding how the sky works. This knowledge comes only by spending time under the stars with star maps in hand."This Week's Planet Roundup
Mercury is low in the glow of sunrise. By week's end it's becoming easier to see, low in the east-northeast as shown above.
Venus and Jupiter are the two bright "stars" in the west during and after twilight. They shine at an impressive magnitude –4.5 and –1.8, respectively. They continue closing in on each other: from 7° apart on June 19th to 2° on the 26th.
They'll have a spectacularly close appulse (closest approach) on June 30th: only 1/3° apart at dusk for the time zones of the Americas. (Their actual conjunction in right ascension comes on July 1st, when they're slightly farther apart.)
Mars is hidden deep in the glare of sunrise.
Saturn (magnitude +0.2, above the head of Scorpius) is highest in the south soon after dark. About 12° lower left of Saturn twinkles fiery orange Antares, not quite as bright.
Uranus (magnitude +5.9, in Pisces) and Neptune (magnitude +7.9, in Aquarius) are well up in the east and southeast, respectively, before dawn begins to brighten. Finder charts.
All descriptions that relate to your horizon — including the words up, down, right, and left — are written for the world's mid-northern latitudes. Descriptions that also depend on longitude (mainly Moon positions) are for North America.
Eastern Daylight Time (EDT) is Universal Time (UT, UTC, or GMT) minus 4 hours.
“This adventure is made possible by generations of searchers strictly adhering to a simple set of rules. Test ideas by experiments and observations. Build on those ideas that pass the test. Reject the ones that fail. Follow the evidence wherever it leads, and question everything. Accept these terms, and the cosmos is yours.”
— Neil deGrasse Tyson, 2014
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