Selasa, September 30, 2008

SELAMAT HARI RAYA IDUL FITRI 1429 H


Get Hari Raya Graphics Here



Get Hari Raya Graphics Here



Jika Cinta adalah Istana, Maka Kejujuran adalah singgasana..
Jika kesetiaan adalah mahkota, maka maaf seorang sahabat adalah keabadian tahta..

KAMI DARI SELURUH PENGURUS FOSCA MENGUCAPKAN :

Selamat Hari Raya Idul Fitri 1429 H.

Minal Aidzin Walfaidzin..
Mohon Maaf Lahir Dan Batin

Jumat, September 26, 2008

FOSCA Goes To School

Beberapa hari yang lalu, tepatnya hari minggu, 21 september 2008.. suatu kesempatan yang sangat menyenangkan bagi FOSCA. karena ini adalah kesempatan yang pertama kalinya FOSCA tampil di depan publik.

FOSCA hadir dalam acara Pesantren Ilmiah Remaja yang diadakan oleh KIR dari SMAN 4 Bekasi. Perwakilan dari FOSCA yang kali ini hanya dari SMAN 38 Jakarta yaitu Indra Firdaus dan dari SMAN 34 Jakarta yaitu Titania Virginiflosia berangkat menuju lokasi dari Planetarium pukul 11.30 Kebetulan FOSCA hadir dalam acara tersebut berkat Pembina yang mengajak kita untuk mengisi materi di acara tersebut.

Perjalanan cukup jauh.. Sampe2 kita sendiri bingung.. udah mana panas banget..
Sampai lokasi sekitar jam 1.. kemudian kita langsung sholat terlebih dahulu..
Setelah sholat kita langsung masuk materi.. Materi pertama diberikan oleh Kak Nurdiansah selaku pembina FOSCA.. beliau memberikan materi tentang Astronomi dalam Islam..

Pemberian Materi Oleh Kak Nurdiansah



Setelah Kak Nurdin memberikan materi, ada jeda istirahat.. jeda istirahat ini dipakai oleh panitia untuk memasang film upin dan ipin. film ini membuat para peserta tertawa terbahak2.

Film yang totalnya 6 episode di setel hanya 3 episode. dan langsung jeda untuk sholat Ashar..

Setelah jeda sholat ashar.. ini dia waktu yang paling ditakutkan oleh FOSCA.. pemberian materi tentang KIR.. Asal usul FOSCA didirikan.. dan kemudian sesi tanya jawab..
Persiapan Materi Oleh FOSCA

Materi yang di sajikan hanya berkisar tentang FOSCA.. kegiatan apa saja yang sudah dilakukan oleh FOSCA.. Peserta dari KIR SMAN 4 Bekasi sangat antusias dengan FOSCA.. Hanya saja mereka sedikit kecewa karena untuk tahun ini dan tahun 2009.. Kegiatan yang diadakan oleh FOSCA hanya berkisar tentang Astronomi..

Pemberian materi oleh FOSCA [Indra Firdaus]

Materi Astronomi dalam Islam Oleh Kak Nurdiansah

Memperkenalkan Astronomy Project dari FOSCA oleh KIR SMAN 4 Bekasi

Tanya jawab yang di moderatori oleh Dio [ KIR SMAN 4 Bekasi ]

Kegiatan ini dilaksanakan sampai buka puasa.. FOSCA berbuka puasa bersama para Peserta dari SMAN 4 Bekasi dan juga dari Alumni2 KIR SMAN 4 Bekasi yang rata2 mereka sudah bekerja..

Persiapan berbuka puasa oleh akhwat KIR SMAN 4 Bekasi

Ramah tamah dengan Alumni KIR SMAN 4 Bekasi

Well.. Dari FOSCA untuk acara tersebut sangat menarik, menambah pengalaman FOSCA dalam hal Presentasi..

Kawan.. Harap sabar yah untuk Penelitian yang lain.. Sedang diusahakan..
Thank's..

-RigeL

Rabu, September 24, 2008

Electrical Activity on Titan Confirmed: The Spark for Life?

NASA/JPL/Space Science Institute/ESA

Titan not only has an atmosphere it has hydrocarbon lakes, oceans, sand dunes and now research has just been published proving Saturn's moon is sparkling with electrical activity. Scientists are in general agreement that organic molecules, the precursors to life on Earth, are a consequence of lightning in the atmosphere. Now, using data from the Huygens probe that descended through Titan's atmosphere in 2005 and continued transmitting for 90 minutes after touchdown, Spanish scientists have "unequivocally" proven that Titan has electrical storms too. The presence of electrical activity in the atmosphere is causing much excitement as this could mean that organic compounds may be found in abundance on the Titan surface.

The fruits from the Cassini-Huygens mission are coming thick and fast. Only yesterday, Nancy reviewed the discovery of liquid hydrocarbon lakes by Cassini's Visual and Infrared Mapping Spectrometer (VIMS). Although possible lakes have been theorized, it is only now that there is observational proof of the existence of such features. Now, three years after the Huygens probe dropped through Titan's atmosphere, scientists have made another crucial discovery: Titan experiences electrical activity in its atmosphere. Now Titan has all the necessary components for life; it has an atmosphere with electrical activity, increasing the opportunity for prebiotic organic compounds to form, thus increasing the possibility for life to evolve.

According to Juan Antonio Morente from the University of Granada, Titan is already considered a "unique world in the solar system" since the early 20th Century when Spanish astronomer José Comas y Solá made the discovery that the Saturn moon had an atmosphere. This is what makes Titan special, it has a thick atmosphere, something that is not observed on any other natural satellite in the Solar System.

"On this moon clouds with convective movements are formed and, therefore, static electrical fields and stormy conditions can be produced. This also considerably increases the possibility of organic and prebiotic molecules being formed, according to the theory of the Russian biochemist Alexander I. Oparín and the experiment of Stanley L. Miller [who managed to synthesise organic compounds from inorganic compounds through electrical discharges] That is why Titan has been one of the main objectives of the Cassini-Huygens joint mission of NASA and the European Space Agency" - Juan Antonio Morente.

Morente and his team analysed data from Huygens' Mutual Impedance Probe (MIP) that measured the atmospheric electrical field. The MIP instrument was primarily used to measure the atmosphere's electrical conductivity but it also acted as a dipolar antenna, detecting the natural electric field. The MIP was therefore able to detect a set of spectral peaks of extremely low frequency (ELF) radio signals (known as "Schumann resonances"). These ELF peaks are formed between the moon's ionosphere and a huge resonant cavity in which electromagnetic fields are confined.

The detection of these signals have led the Spanish researchers to state that it is "irrefutable" evidence of electrical activity on Titan, not dissimilar to static charge that builds up in the terrestrial atmosphere, leading to electrical storms.

Source: Scientific Blogging

Karya Astronom Indonesia

Bagaimana sebuah sistem planet terbentuk? Se-umum apakah keberadaan sistem planet di alam semesta ini? Bagaimana susunannya dan berapa banyak planet mirip Bumi yang mendukung kehidupan ada di Galaksi bimasakti? Atau lebih jauh lagi, adakah kehidupan lain di semesta yang luas ini? Sepanjang dekade terakhir, astronom berhasil menuju pada jawaban pertanyaan-pertanyaan tersebut dengan penemuan sistem ekstrasolar pada bintang serupa Matahari sejak tahun 1995. Semenjak itu berbagai sistem telah ditemukan. Bahkan diketahui memang ada planet yang tergolong planet pendukung kehidupan di sistem bintang Gliese 581.

Nah, bagaimana planet terbentuk? Yang kita ketahui, planet terbentuk dari debu dan gas pada piringan disekeliling bintang tak lama setelah sebuah bintang terbentuk. Planet akan terbentuk melalui proses tabrakan diantara materi-materi debu dari ukuran butiran debu menjadi embrio planet. Saat inti planet tumbuh dan sudah cukup masif, ia akan mulai mengakresi materi gas yang ada di piringan disekelilingnya. Alternatif lainnya, planet-planet raksasa diperkirakan terbentuk dari ketidakstabilan gravitasi di dalam piringan bintang tersebut. Skala waktu pembentukan planet ini juga ditentukan dari proses hamburan di dalam piringan. Dari hasil pengamatan bintang-bintang muda, diketahui kalau piringan tersebut terbentuk dalam waktu 10 juta tahun setelah bintang terbentuk.

Sampai saat ini survei untuk extrasolar planet belum pernah menemukan planet disekitar bintang yang lebih muda dari 100 juta tahun. Satu-satunya planet yang masih muda ditemukan dengan meggunakan teknik direct imaging pada jarak 55 SA di bintang katai coklat 2MASS1207.


Illustrasi artis untuk TW Hydra (T Hya). Kredit : Johny Setiawan (JSW art 2007)

Kali ini, tim astronom dari Max Planck Institute for Astronomy (MPIA) di Heidelberg berhasil menemukan sistem extrasolar termuda dengan metode variasi kecepatan radial. Metode kecepatan radial mendeteksi perubahan kecepatan gaya gravitasi dari exoplanet (yang tak terlihat) saat ia mengorbit bintangnya.

Sistem yang ditemukan tersebut mengitari bintang muda yang masih dikelilingi oleh piringan gas dan debu yang baru saja membentuk dirinya. Penemuan ini akan memberi informasi yang penting bagi kita dalam hal waktu pembentukan planet dan memberi kunci penting dalam memahami bagaimana dan dimana planet terbentuk. Sebuah jawaban dari pertanyaan yang menjadi misteri selama berabad-abad. Tim astronom dari MPIA telah memonitor variasi kecepatan radial dari sekitar 200 bintang dalam pencarian sistem ekstrasolar. Salah satu diantaranya adalah bintang TW Hydrae, yang berusia 8 - 10 juta tahun (sekitar 1/500 umur Matahari). Sama seperti bintang yang masih muda, TW Hydrae juga masih dikelilingi piringan debu dan gas antar bintang, yang diyakini sebagai tempat lahirnya planet-planet.

Tim yang dipimpin Johny Setiawan yang juga astronom asal Indonesia ini berhasil menemukan planet yang mengorbit bintang TW Hydrae di bagian dalam piringan tersebut. Menurut Johnny, planet tersebut ditemukan saat mereka memantau kecepatan radial TW Hydrae. Saat itu mereka mendeteksi adanya variasi periodik yang bukan ditimbulkan oleh aktivitas bintang, namun mengarah pada keberadaan planet. Deteksi dilakukan dengan menggunakan spektograf FEROS pada teleskop 2,2 milik Max-Plank Institute dan ESO di La Silla, Chille.

TW-Hydra b yang baru ditemukan tersebut cukup masif dengan massa sekitar 10 kali massa Jupiter, dan mengelilingi bintang induknya hanya dalam waktu 3,56 hari pada jarak 6 juta km, atau sekitar 4% dari jarak Bumi-Matahari.

Pencarian planet pada bintang muda tentu tak lepas dari masalah aktivitas bintang, karena bintang di usia yang masih muda permukaannya masih tidak stabil. Salah satu contohnya, bintik bintang sangat besar dan bintik tersebut bisa meniru variasi kecepatan radial yang disebabkan oleh planet yang mengorbit. Menurut Ralf Launhart, untuk meniadakan berbagai kesalahan interpretasi, mereka telah meneliti seluruh indikator aktivitas dari TW Hydra secara mendetail. Hasilnya, mereka menemukan kalau karakteristik dari aktivitas bintang sangat berbeda, yakni tidak terlalu umum terjadi dan memiliki periode yang lebih pendek.

Penemuan TW Hydra b justru memberi angin segar dan bukti pertama dalam dunia teori pembentukan planet. Jika didasarkan pada studi statistik, masa hidup piringan antar bintang rata-rata sekitar 10-30 juta tahun. Ini menunjukan, kalau waktu maksimum yang tersedia untuk terbentuknya planet di dalam piringan hanya sampai 30 juta tahun. Dengan demikian TW Hydra b planet gas yang 10 kali lebih masif dari jupiter tersebut, terbentuk dalam waktu yang sangat singkat hanya pada kisaran 8 - 10 juta tahun.

Para peneliti di Max - Planck saat ini juga tengah mengembangkan instrumen generasi baru untuk mendeteksi extrasolar planet dengan teknik lainnya, seperti direct imaging, pengukuran gerak refleks yang sangat halus dari bintang pada bidang langit (astrometri), maupun untuk transit fotometri. Diharapkan di masa depan intrumen ini dapat mendeteksi planet-planet yang tidak dapat terdeteksi oleh metode kecepatan radial.

Semakin banyak penemuan sistem keplanetan tentu akan memberi pemahaman yang lebih luas dan lebih beragam mengenai sistem keplanetan itu sendiri. Di titik itu kita akan menempatkan Tata Surya dalam sebuah konteks universal dan mulai mencari sebuah jawaban lanjutan dari pertanyaan yang tak pernah mati, adakah teman di luar sana?


Source : Langitselatan

Atlantis Crew Preps For Mission to Hubble

Astronauts Prepare for Countdown Rehearsal

On Wednesday morning, the STS-125 astronauts will suit up in their orange launch-and-entry suits, ride to the launch pad aboard the Astrovan, and climb into space shuttle Atlantis for a countdown dress rehearsal. This countdown practice caps three days of standard prelaunch exercises for the crew at NASA’s Kennedy Space Center in Florida.

After meeting with members of the news media Tuesday morning, the astronauts trained for emergency egress at the launch pad. During their first day of activities, the crew members practiced driving the M-113 armored personnel carrier as part of their emergency training procedures. Commander Scott Altman and Pilot Gregory Johnson flew simulated landings in the Shuttle Training Aircraft.

Following the launch dress rehearsal, the astronauts will return to their home base at NASA’s Johnson Space Center in Houston to continue training for their mission to service the Hubble Space Telescope.

STS-125 Mission Specialist Megan McArthur.
Image above: STS-125 Mission Specialist Megan McArthur participates in emergency egress training at Launch Pad 39A.
Image credit: NASA



While the astronauts’ activities are centered at Launch Pad 39A, space shuttle Endeavour is nearby at Launch Pad 39B where it will be on standby in the unlikely event that a rescue mission for the Atlantis's crew would be necessary. After Endeavour is cleared from its duty as a rescue vehicle, workers will move it to pad 39A in preparation for liftoff on mission STS-126 to the International Space Station in November.

Source : NASA

Jumat, September 19, 2008

International Years Of Astronomy 2009

IYA Logo

Tanggal 20 Desember 2007 yang lalu, Perserikatan Bangsa-Bangsa, melalui sidang Majelis Umum ke-62, secara resmi mendeklarasikan tahun 2009 sebagai Tahun Astronomi Internasional – International Year of Astronomy (IYA2009). Hal ini ditujukan untuk memperingati 400 tahun penggunaan teleskop untuk pertama kalinya bagi keperluan astronomi oleh Galileo Galilei. Resolusi ini merupakan prakarsa dari International Astronomical Union (IAU) dan UNESCO, dan diajukan ke PBB oleh Italia sebagai negara asal dari Galileo. (Tahun 2005, PBB menyatakannya sebagai Tahun Fisika Internasional, untuk memperingati seabad penemuan teori relativitas khusus oleh Einstein).

Perjalanan untuk sampai pada deklarasi resolusi secara resmi ini sendiri sangatlah panjang. Bermula dari ketetapan IAU pada sidang Majelis Umum tanggal 23 Juli 2003 di Sydney, Australia, yang secara aklamasi mengusulkan tahun 2009 sebagai Tahun Astronomi Internasional. Berikutnya, usulan ini diajukan ke UNESCO atas prakarsa Italia dan akhirnya diterima oleh Konferensi Umum UNESCO pada sesi ke-33 tahun 2006, dan kemudian direkomendasikan oleh UNESCO ke PBB. Dengan resolusi ini, PBB menetapkan UNESCO sebagai lead agency dan IAU sebagai badan fasilitator untuk IYA2009.

Sebagaimana kita ketahui, pengamatan astronomi menggunakan teleskop oleh Galileo menghasilkan penemuan-penemuan astronomi yang fundamental dan telah memicu revolusi saintifik yang mengubah pandangan kita tentang alam semesta secara mendalam. Penemuan bulan-bulan Jupiter oleh Galileo memberikan bukti untuk membantah konsep geosentrik. Kemudian hukum gerak planet memberikan fondasi penting bagi penemuan hukum-hukum mekanika oleh Isaac Newton. Sains moderen kemudian tumbuh sangat pesat. Dewasa ini, teleskop-teleskop, baik landas-bumi maupun landas-layang (di antariksa), terus menyelidiki alam semesta, 24 jam sehari pada seluruh panjang gelombang.

IYA2009 menggarisbawahi kerjasama global bagi perdamaian – pencarian asal-usul kita dalam kosmos dan warisan kita bersama yang menghubungkan seluruh warga planet Bumi. Selama ribuan tahun, para astronom telah bekerja bersama-sama menembus semua batas termasuk batas-batas geografis, gender, usia, budaya, dan ras, sesuai dengan piagam PBB. Dalam pengertian ini, astronomi merupakan contoh klasik bagaimana sains dapat berkontribusi untuk memajukan kerjasama internasional. Astronomi merupakan sumber inspirasi tak ternilai bagi kemanusiaan di seluruh bangsa-bangsa.

IYA2009, pertama dan utamanya, adalah suatu aktivitas bagi warga planet Bumi, yang ditujukan untuk berbagi pengetahuan fundamental tentang alam semesta dan tempat kita di dalamnya. Sejauh ini sudah terdapat 100 negara dan 14 organisasi yang menyatakan turut serta merayakan IYA2009; termasuk Indonesia. Bangladesh adalah negara ke-100 yang menyatakan partisipasinya pada IYA2009. Berbagai persiapan sedang dilakukan menyongsong perayaan ini, dan di Indonesia kegiatan ini dikoordinasi oleh Observatorium Bosscha.


Berikut di bawah ini terdapat satu paragraph utuh yang diambil dari sambutan presiden IAU yaitu Catherine Cesarsky.

"Astronomy is one of the oldest fundamental sciences. It continues to make a profound impact on our culture and is a powerful expression of the human intellect. Huge progress has been made in the last few decades. One hundred years ago we barely knew of the existence of our own Milky Way. Today we know that many billions of galaxies make up our Universe and that it originated approximately 13.7 billion years ago. One hundred years ago we had no means of knowing whether there were other solar systems in the Universe. Today we know of more than 200 planets around other stars in our galaxy and we are moving towards an understanding of how life might have first appeared. One hundred years ago we studied the sky using only optical telescopes and photographic plates. Today we observe the Universe from Earth and from space, from radio waves to gamma rays, using cutting edge technology. Media and public interest in astronomy have never been higher and major discoveries are frontpage news throughout the world. The IYA2009 will meet public demand for both information and involvement."

pada kalimat yang di bold, kurang lebih terjemahannya adalah sebagai berikut:

"Astronomi adalah salah satu ilmu pengetahuan pokok tertua. Itulah yang terus memberikan dampak kuat pada kebudayaan kami dan ungkapan perasaan kuat manusia. Kemajuan yang besar telah diraih pada dasawarsa akhir ini. Seratus tahun yang lalu kami baru saja mengetahui keberadaan kami sendiri di Bima Sakti. Hari ini kami mengetahui banyak milyaran galaksi tercipta di Alam Semesta kami, dan itu telah dimulai sekitar 13,7 milyar tahun yang lalu. Seratus tahun yang lalu kami tidak mempunyai alat untuk mengetahui apakah ada sistem tata surya lain di Alam Semesta. Hari ini kami mengetahui lebih dari 200 planet disekitar bintang lain di galaksi kami dan kami bergerak ke arah pengetahuan tentang bagaimana awal kehidupan yang besar mulai tampak. Seratus tahun yang lalu kami belajar tentang langit yang hanya memakai teleskop optik dan plat fotografis. Hari ini kami mengamati Alam Semesta dari Bumi hingga angkasa, dari gelombang radio ke sinar gamma, menggunakan teknologi teratas."

Kamis, September 18, 2008

Hubble Servicing Mission Essentials


Galaxies from the early universe. The birthplaces of planets. Dark matter. Dark energy. Since its launch in 1990, the Hubble Space Telescope has brought these mysteries into focus, its powerful gaze scanning the universe for the details planet-bound telescopes find impossible to detect.

Far above the Earth's surface, Hubble floats clear of the planet's light-distorting atmosphere, beaming back images that have transfixed humanity and changed the scientific world.

Hubble's triumphs continue to accumulate thanks to a unique design that allows astronauts to repair and upgrade the telescope while it remains in orbit. Repairs keep the telescope functioning smoothly, while upgrades to the instruments bring a slew of new discoveries and science.

Meet the crew that will give Hubble its extreme makeover. Image Credit: NASA

On October 10, 2008, astronauts will board the Space Shuttle Atlantis for Servicing Mission 4 (SM4), the final trip to the Hubble Telescope. Over the course of five spacewalks, they will install two new instruments, repair two inactive ones, and perform the component replacements that will keep the telescope functioning at least into 2014. The effort-intensive, rigorously researched, exhaustively tested mission also involves diverse groups of people on the ground throughout the country.

Ready, Set, Go

The mission's planning is years in the making, and its success will be the product of months of intensive preparation and the work of hundreds of people at NASA and in academia and industry.

Astronauts train at NASA's Johnson Space Center in Texas, where they learn to deal with weightlessness in a giant water tank in the Neutral Buoyancy Lab, and at Goddard Space Flight Center in Maryland, where they enter Goddard's huge intensively filtered "clean room" to work with the actual equipment they'll use and install aboard Hubble. Goddard prepares and tests instruments and hardware, while Kennedy Space Center in Florida prepares the space shuttle for the mission.


Read these behind-the-scenes stories leading up to the mission
+ Goddard Engineers and Divers Multi-Task for Hubble
+ NASA's Clean Room: Last Stop for New Hubble Hardware
+ NASA Goddard Provides Environmental Testing for Hubble Components
+ Hubble's In-Flight Guidance from the Ground

During SM4, teams at Johnson and Goddard work around the clock to make sure the mission succeeds. Johnson's Mission Control Center monitors the space shuttle and astronauts, and supervises spacewalks, procedures, crew activities and health, as well as shuttle systems and experiments. Hubble personnel, including managers, scientists, and engineers from Goddard and the Space Telescope Science Institute in Maryland, will be split between supporting the mission at Johnson and those working at Goddard.

At Goddard, where the Hubble program is administered, the Space Telescope Operations Control Center controls the telescope itself, giving the commands that prepare the telescope for the astronauts' activities and test the newly installed equipment. Goddard's Control Center closes the door that protects the telescope's delicate optics, and maneuvers Hubble into position as the shuttle Atlantis approaches.

When the shuttle is about 200 feet (60 m) away from Hubble, Goddard will command the telescope to execute a roll that brings it into position for grappling. Astronauts use the shuttle's robotic arm to capture Hubble and dock it in the shuttle's cargo bay.

The Shuttle robotic arm captures the Hubble Telescope Image Credit: NASA

Next, the astronauts begin their series of five six-and-a-half-hour spacewalks. Two astronauts work outside on Hubble at a time. One mainly handles the free-floating tasks. The other is connected by a foot restraint to the robotic arm, which is operated by a third astronaut from within the shuttle. To keep themselves from accidentally floating away, the astronauts attach safety tethers to a cable that runs along the cargo bay. Hubble was built with handrails that also make it easy for astronauts to cling to the telescope.

A team of astronauts perform upgrades on the telescope during a spacewalk in the 2002 servicing mission. One astronaut uses a handrail (left) to hold onto Hubble while the other is attached to the shuttle's robotic arm by a foot restraint (right) Image Credit: NASA

Out With the Old
Many of the telescope's components, especially the instruments, were designed to be easily removed and replaced during servicing missions. This mission's primary scientific priority is the installation of Hubble's new instruments, Wide Field Camera 3 (WFC3) and the Cosmic Origins Spectrograph (COS).

Wide Field Camera 3 will be the power behind studies of dark energy and dark matter, the formation of individual stars and the discovery of extremely remote galaxies previously beyond Hubble's vision. WFC3 sees three different kinds of light: near-ultraviolet, visible and near-infrared, though not simultaneously. The camera's range is much greater than that of the instruments currently aboard.

COS (black box) sits in its protective carrier waiting for delivery to the Hubble Telescope. This same carrier will protect COSTAR on its trip back to Earth at the end of the mission. Image Credit: NASA

Galaxy evolution, the formation of planets, the rise of the elements needed for life, and the "cosmic web" of gas between galaxies will be some of the areas of study for the Cosmic Origins Spectrograph (COS). A spectrograph is an instrument that breaks light into its component colors, revealing information about the object emitting the light. COS sees exclusively in ultraviolet light and will improve Hubble's ultraviolet sensitivity at least 10 times, and up to 70 times when observing extremely faint objects.

COS will take the place of the device installed in Hubble during the first servicing mission to correct Hubble's flawed mirror, the Corrective Optics Space Telescope Axial Replacement (COSTAR). Since the first servicing mission, all of Hubble's replacement instruments have had technology built in to them to correct Hubble's marred vision, making COSTAR no longer necessary.


Get the facts behind the instruments. Read these related Fact Sheets:
+ Advanced Camera for Surveys Repair
+ Space Telescope Imaging Spectrograph Repair
+ Wide Field Camera 3
+ Cosmic Origins Spectrograph

The Fix is in

Mission astronaut Mike Massimino uses a specially designed "fastener capture plate" (blue and red plate) during a STIS repair practice. The plate locks onto the instrument cover and captures the fasteners holding the cover in place as the astronaut unscrews them.
Image Credit: NASA


Two of Hubble's instruments, the Advanced Camera for Surveys (ACS) and the Space Telescope Imaging Spectrograph (STIS), are in need of repair. ACS, which partially stopped working in 2007 due to an electrical short, is the "workhorse camera" responsible for some of Hubble's most spectacular images. STIS is a spectrograph that sees ultraviolet, visible and near-infrared light, and is known for its ability to hunt black holes. While COS works best with small sources of light, such as stars or quasars, STIS can map out larger objects like galaxies. STIS suffered a power failure in 2004 and was put into hibernation to preserve the possibility of its repair.

Astronauts plan to fix both – a challenging prospect since these repairs are beyond the scope of Hubble’s serviceable design. Hubble’s creators envisioned astronauts swapping out components, not performing delicate surgeries during spacewalks.

An interior electronics box of ACS that supplies power for ACS detectors, contains equipment affected by an electrical short. However, its location makes it inaccessible to astronauts. So instead of trying to reach the problem area, astronauts will attempt to bypass those power-shorted components entirely.

The failed power supply is connected by cables to a series of electronics boards, which are within reach but have no power because of the damaged box. Astronauts will install a new power supply to a handrail on the ACS outer enclosure, remove the electronics boards and install different ones that are compatible with the new power supply, and connect them to the new supply with exterior cables. The arrangement simply cuts the damaged box out of the equation.

Innovative tools for the repairs are designed and developed by Goddard engineers and tested by the astronauts for refinements.
Image Credit: NASA


STIS needs a new power supply circuit board. The repair would be relatively easy but for the electronics access panel, which was never meant to be opened and is attached to STIS by 111 small screws. The screws are hard to grasp with the astronauts' gloved hands, and could create problems if they were to escape and float around the electronics. So engineers have created a "fastener capture plate" that fits over the top of the panel. When the astronauts remove the screws, they will be trapped in the plate. Astronauts will then switch out the power supply circuit board and close off the open electronics with a new, simpler panel that attaches easily with two levers.

As each of Hubble's instruments and components is repaired or installed, Goddard performs tests to ensure that everything is working correctly. Once the work is completed, Hubble will be ready for peak performance with a grand total of five instruments: WFC3, COS, ACS, STIS and the Near-Infrared Camera and Multi-Object Spectrograph (NICMOS).

Routine Maintenance
But before it can try out its new equipment, the telescope needs maintenance. Hubble's batteries store the energy that powers the telescope during the "nighttime" portion of its orbit, when the Earth blocks the Sun's rays. Astronauts will replace all six of Hubble's 125-pound batteries with new, more effective versions.

An astronaut replaces a battery module. Image Credit: NASA

The telescope's six gyroscopes are part of the system that points the telescope. When all six gyroscopes are functioning, three gyroscopes are used for pointing, and the other three are held in reserve. Time has degraded the gyroscopes to the point where three have failed, two are in use, and a third is turned off to be used as an emergency backup. Astronauts will install six new gyroscopes.

Behind a pair of aft shroud doors, Hubble's six gyroscopes are found within 3 rate sensor units (circled in image). Image Credit: NASA

Hubble's Fine Guidance Sensors (FGS) lock onto guide stars, helping the telescope point. They can also be used as instruments to measure the position of stars in relation to other stars. Astronauts will replace one worn-out FGS with a refurbished model that was removed during a previous servicing mission.

Hubble's insulating blankets, which maintain the telescope's normal operating temperature, eventually break down because of their exposure to space. Astronauts will cover key Hubble equipment bays in fresh insulation, also called a New Outer Blanket Layer (NOBL).

Finally, they will install a new device, the "soft capture mechanism." This simple device will allow a robotic spacecraft to attach itself to Hubble someday, once the telescope is at the end of its life.


Get the facts behind the maintenance activities. Read these related Fact Sheets:
+ Batteries
+ Gyroscopes
+ Fine Guidance Sensor
+ New Outer Blanket Layer
+ Soft Capture and Rendezvous System


Release of Hubble from space shuttle Atlantis after servicing. Image Credit: NASA

When the astronauts have finished all of their tasks, they will use the robotic arm again to release the telescope, and Goddard will issue the commands to bring the telescope back into operation. But before Hubble's science mission can resume, the telescope will undergo a several-month-long testing and calibrating period. The first new images from the telescope will be released in early 2009.

Restored and updated, Hubble will continue on its journey around the Earth, its new components merging seamlessly with the old, a rejuvenated telescope ready for years of groundbreaking revelations from the universe.


Source : NASA

Dan Lukisan Langit pun Berubah

Do you know, di kubah langit bintang tidak diam saja? Ini bukan soal terbit-tenggelam atau rasi apa dilihat pada bulan apa. Pernah membayangkan atau bertanya-tanya apakah neneknya neneknya neneknya … nenekmu melihat rasi Leo Sang Singa, misalnya, sama persis dengan apa yang kita lihat pada zaman sekarang?

Para astronom zaman dulu sudah bisa membedakan mana “bintang tetap” mana “bintang pengembara” (planet). Planet tampak oleh mereka bergerak di antara bintang-bintang dari rasi ke rasi. Seandainya malam ini kamu melihat planet Jupiter di sebelah Barat rasi Scorpio, beberapa malam kemudian dia akan berada di Timurnya.

Bagaimana dengan bintang? Menurut catatan kuno dua abad yang lalu, bintang-bintang di rasi Scorpio juga membentuk “gambaran” kalajengking seperti yang kita lihat sekarang. Sebenarnya bintang juga bergerak. Namun, karena begitu jauh jaraknya dari kita, pergerakan itu hampir tak teramati. Setelah ratusan ribu tahun akibat pergerakannya itu baru kelihatan. Laju perubahan itulah yang disebut gerak diri (proper motion) bintang.


Rasi Leo saat 100000 SM dan sekarang.

Gerak proper bintang pada bidang langit.

Konsep yang lumayan rumit? OK, begini, bintang-bintang di Galaksi Bima Sakti ini rata-rata bergerak dengan kecepatan 10 km per detik atau 36.000 km per jam. Wow! Cepat sekali! Tapi, pertanyaannya adalah bisakah kita melihat gerakan ini dalam satu malam? Dengan kecepatan sebesar itu, dalam waktu satu jam bintang menempuh jarak 36.000 km. Andaikan bintang itu adalah Proxima Centauri, bintang yang terdekat dengan Matahari, yang berjarak 100 triliun kilometer. Jarak sudut bintang (pergeseran posisi bintang di langit) itu, katakanlah a, adalah sebesar 57,3 x (pergeseran sesungguhnya/jarak) = 57,3 (36.000 km / 100 triliun km). Seperseratus juta derajat atau sekitar sepersejuta detik busur! Sudut yang sangat kecil! Hanya dalam hitungan puluhan tahun perubahan itu baru akan teramati.

Para astronom menyatakan laju perubahan sudut ini dalam satuan detik busur per tahun (“/tahun). Bintang Barnard adalah bintang yang memiliki gerak diri paling besar, yaitu 10,25 “/tahun (dalam waktu 180 tahun bintang ini bergeser selebar bentangan bulan purnama).

Umumnya bintang-bintang mempunyai gerak sejati hanya 0,1 “/tahun. Setelah 20 atau 50 tahun perubahan posisinya baru teramati dan gerak dirinya bisa dihitung. Caranya? Dengan membandingkan dua foto daerah langit yang sama dengan pengambilan berselang waktu setidaknya selama 20 tahun. Itu pun baru pergeseran yang tampaknya tidak berarti kalau yang dibayangkan adalah perubahan bentuk suatu rasi.

Seandainya dihitung untuk katakanlah misalnya sejuta tahun yang lalu atau sejuta tahun yang akan datang? Manusia tentunya tidak bisa menunggu selama itu. Dengan simulasi komputer, bentuk rasi, misalnya rasi Beruang Besar (Ursa Mayor), bisa dilihat mundur ke masa lalu, ke zaman ratusan, ribuan, ratusan ribu tahun yang lalu. Hasilnya memperlihatkan penampakan yang sama sekali berbeda. Dia tak lagi layak mendapatkan nama Beruang Besar. Pada waktu itu bentuknya mirip lembing. Seandainya kita punya mesin waktu yang melemparkan kita ke zaman antah berantah, lalu kita melihat rasi yang seperti itu, kita bisa memperkirakan kita berada pada zaman apa, yaitu masa Pleistocene Pertengahan.

Perubahan posisi bintang dalam rasi Ursa Majoris atau Rasi Beruang Besar dari tahun 100000 SM - 100000 M

Dalam heningnya malam ini mengamati langit, duduk diam sambil memejamkan mata, membayangkan bintang-bintang di kubah langit atas sana, bergerak membentuk gambaran yang sama sekali berbeda dengan yang selama ini kita kenal…



Source : Langitselatan.com

Selasa, September 02, 2008

LUNAR ECLIPSE ON INDONESIA’S INDEPENDENCE DAY

A day before Indonesia’s Independence day, exactly at August, 16th 2008 ( Please note that Indonesia took August, 17th our Independence day instead of December, 27th that usually seen in International history books was taken from the Dutch acceptance on Indonesia’s Independence ). We, in collaboration with Al – Izhar Senior High School Astronoy Club, held an event to observe the partial lunar eclipse. In the night, HAAJ gave two lectures. The first is about the theories of Eclipse and the second one is about black hole. The first lecture was given by Gabriel from Astronomy Study Program of ITB. As for the second one, we were surprised by Dino, an 11 years old boy who presented us to that ‘Heavy’ subject when we’re in that age even we can’t explain Solar System well, holy crap. Also, we were again surprised that he can’t speak Bahasa Indonesia well. So, Instead of using that, he used Englisch which is Difficult to understand for some of us. However, night observation awaited us just after that. But unfortunately, the weather wasn’t very good yet the moonbeam was too luminous. The moon and Jupiter , were the only object that we can observe yet again, please note that jakarta’s night sky is Heavly pollused. It’s just too bad for us who lived around there

Registrasi Peserta Penelitian Gerhana Bulan Parsial

Menunggu Pembukaan Acara dari SMA Al Izhar Pondok Labu


Makan-makan dulu sebelum berperang.. Hehehe..

Presentasi Tentang Gerhana Bulan dari Kak Gaby [ Mahasiswa ITB Astronomi ]

Presentasi tentang Black Hole Dari Dino [ HAAJ ]

Let The Eclipse Start!

The penumbral eclipse started on 01.24 WIB. But there’s no extreme difference between the eclipse and the normal full moon. At 3 o’clock we finally see the dark umbra cover one per third area of moon. Of course, we didn’t forget to take the photograph on the eclipse. We just used a common digital camera that we can see almost everywhere in automatic mode. We used Meade Refractor with addition of Vixen digital camera adapter. Nonetheless, we were quite satisfied with the result yes, we knew that they’re underexposed. More over, while Meade was busy to take the photo of the eclipse. There were 4 unused telescopes uot there. Since the moon’s luminosity had decreased, it means there will be more object to observe! Great Nebula in Orion and The Pleiades Cluster were Visible that time, In an instant. We pointed the telescopes to those objects. It’s not as beautiful as the pictures that Hubbe gave to us. But they were pretty good and enjoyable as well. At 05.56 WIB, the sun had raised. So say goodbye to the eclipse because it won’t just 10 minutes before sunrise.

Setting Teleskop Dulu..

Beginiliah suasana saat pengambilan data di SMA AL - Izhar Pondok Labu

Antri liat bulan dari teleskop.. daripada nunggu mending duduk dulu di bawah.. sambila maen suit-suitan.. hehehe..


DETIK-DETIK MENJELANG GERHANA BULAN PARSIAL

Aftermath !

Being slept for only 2 hours, some of us, who matter how uncomfortable the place is, Instantly feel asleep. Even there are some of us who had to attend the Independence Day Ceremony in there own school. Although being very exhausting. This is an event that we can’t forget easly. We hope the next event will be more enjoyable!

ABOUT FOSCA

Fosca at Boscha Observatorium

Fosca is a communication forum for all senior high school students around JABODETABEK are who loved science. Fosca was just founded 5 months ago. Despite of being a newly founded organization, we’ve held 3 major events as apart of our Astronomical Research Program of 2008. They are LDP ( Latihan Dasar Penelitian ; Basic Research Training ), PDA ( Penelitian Dasar Astronomi ; Basic Astronomy Training ) and the lastest one, Partial Moon Eclipse Observation. As for technical and material problems, we’ve got HAAJ’s ( Himpunan Astronomi Amatir Jakarta ; Jakarta Amateur Astronomical Association ) helping hand to hold those events. Not to mention, there still one major event left in our program. It’s the Annular Solar Eclipse Observation. The Ecplise will happen at January, 26th 2009.

Diskusi dengan Pak Hakim L Malasan

Penelitian Dasar Astronomi

Penelitian Dasar Astronomi lit. Basic Astronomy Training was similar to LDP. Despite of its similary, this training was more advanced in both of theory and observation. Bring held in Jakarta Planetarium yet again. The enthusiasm of the participants didn’t decrease. That enthusiasm showed off when the race to assemble the telescope personally starts. Everyone do their best to win the race. Finally, Dessy from 38 SHS won. It’s not yet over. They were given an opportunity to take a photo of the sun with filter, of course. After that all of the participants were taken into the planetarium dome to Study the evolution of the stars.


Merakit Teleskop

Peneropongan Matahari

Latihan Dasar Penelitian

Latihan Dasar Penelitian lit. Basic Research Training was held at June, 21st 2008 on Jakarta Planetarium. As the Preparation for our research program, this event focused to the basic theoritical and practical aspects on astronomy. 87 students from 32 SHS took apart in this event. There was Telescope and astrophotography workshop. As for the theories, we studied about the geometry of solar nd lunar eclipse. Also, our advisor, Nurdiansah, shared his experience on many youth science clubs in java to all participants.


Materi Tentang Gerhan bulan dan Gerhana Matahari dari Kak Rayhan [HAAJ]


 

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