Microbe wakes up after 120,000 years
After more than 120,000 years trapped beneath a block of ice in Greenland, a tiny microbe has awoken. The long-lasting bacteria may hold clues to what life forms might exist on other planets.
The new bacteria species was found nearly 2 miles beneath a Greenland glacier, where temperatures can dip well below freezing, pressure soars, and food and oxygen are scarce.
"We don't know what state they were in," said study team member Jean Brenchley of Pennsylvania State University. "They could've been dormant, or they could've been slowly metabolizing, but we don't know for sure."
Dormant would mean the bacteria were in a spore-like state in which there's not a lot of metabolism going on, so the bacteria wouldn't be reproducing much. It's possible the bacteria could have been slowly metabolizing and replicating.
"Microbes have found ways to survive in harsh conditions for long times that we don't yet fully understand," Brenchley told LiveScience.
To coax the bacteria back to life, Brenchley, Jennifer Loveland-Curtze and their Penn State colleagues incubated the samples at 36 degrees Fahrenheit (2 degrees Celsius) for seven months, followed by more than four months at 41 degrees F (5 degrees C).
The resulting colonies of the originally purple-brown bacteria, now named Herminiimonas glaciei, are alive and well.
"We were able to recover it and get it to grow in our laboratory," Brenchley said. "It was viable."
Such vigor is partially due to the microbe's small size, the scientists speculate. Boasting dimensions that are 10 to 50 times smaller than Escherichia coli, the new bacteria likely could more efficiently absorb nutrients due to a larger surface-to-volume ratio. Tiny microbes like this one can also hide more easily from predators and take up residence among ice crystals and in the thin liquid film on those surfaces.
H. glaciei is not the first bacteria species resurrected after a possibly lengthy snooze beneath the ice. Loveland-Curtze and her team reported another hardy bacterium in the same area that had survived for about 120,000 years as well. Chryseobacterium greenlandensis had tiny bud-like structures on its surface that may have played a role in the organism's survival. Another bacterium survived more than 32,000 years in an Arctic tunnel, and was brought back to life a few years ago.
The harsh conditions endured by these microbes serve as models of other planets.
"These extremely cold environments are the best analogues of possible extraterrestrial habitats," Loveland-Curtze said, referring to the Greenland glacier. "The exceptionally low temperatures can preserve cells and nucleic acids for even millions of years."
And studying such microorganisms may provide insight into what sorts of life forms could survive elsewhere in the solar system.
The new bacterium is described in the current issue of the International Journal of Systematic and Evolutionary Microbiology.
© 2009 LiveScience.com. All rights reserved.
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Space Shuttle Press Kits
NASA produced Mission Press Kits for all shuttle flights except those dedicated to the Department of Defense flights. These kits serve as the foundation for the materials in this section.
PLEASE NOTE*: the data was re-keyed, typographical errors corrected, and the entire series reformatted for style consistency. All graphics from the original press kits have been scanned and are included. Additions to the original press kit data include: crew mission insignias that include official NASA descriptions and photo numbers; crew photos with NASA descriptions and photo ID numbers to the "biography" sections; a graphic showing all shuttle flights through STS-111 have been added to the final page of each kit; and for STS-1 through STS-4, scans of the original color covers have been included.
The documents have been exported to individual Adobe Acrobat PDF files for easy searching and viewing. You will need the free Adobe Acrobat Reader to view these files.
*These materials were provided courtesy of Richard W. Orloff.
http://www.jsc.nasa.gov/history/shuttle_pk/shuttle_press.htm
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PLEASE NOTE*: the data was re-keyed, typographical errors corrected, and the entire series reformatted for style consistency. All graphics from the original press kits have been scanned and are included. Additions to the original press kit data include: crew mission insignias that include official NASA descriptions and photo numbers; crew photos with NASA descriptions and photo ID numbers to the "biography" sections; a graphic showing all shuttle flights through STS-111 have been added to the final page of each kit; and for STS-1 through STS-4, scans of the original color covers have been included.
The documents have been exported to individual Adobe Acrobat PDF files for easy searching and viewing. You will need the free Adobe Acrobat Reader to view these files.
*These materials were provided courtesy of Richard W. Orloff.
http://www.jsc.nasa.gov/history/shuttle_pk/shuttle_press.htm
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new astronomy toolbar for IE
Download the theurbansky toolbar:
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Get our freshest content delivered directly to your browser,
no matter where you are on the Web.
Hand-picked Links
Check out all of our favorite places on the Web.
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http://theurbansky.ourtoolbar.com/
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The Best of Our Site
Get our freshest content delivered directly to your browser,
no matter where you are on the Web.
Hand-picked Links
Check out all of our favorite places on the Web.
Google-Powered Search Box
Search the Web, our site, and other useful engines.
Alerts to Your Desktop
Receive our most important news and announcements instantly.
RSS Reader
Tap into our fave RSS feeds and stay on top of the hottest headlines
http://theurbansky.ourtoolbar.com/
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Nasa Wallpapers
http://www.dl.oxava.com/NASA%20Wallpapers%20Best_Oxava.com.rar
or
http://www.mediafire.com/file/kd3zmtrdtyo/NASA%20Wallpapers%20Best_Oxava.com.rar
or
http://rapidshare.com/files/233668201/NASA_20Wallpapers_20Best_Oxava.com.rar
Password : www.oxava.com
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or
http://www.mediafire.com/file/kd3zmtrdtyo/NASA%20Wallpapers%20Best_Oxava.com.rar
or
http://rapidshare.com/files/233668201/NASA_20Wallpapers_20Best_Oxava.com.rar
Password : www.oxava.com
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Sky Atlas 2000.0 (2nd Edition, Desk Version) by Wil Tirion & Roger W. Sinnott
Sky Atlas 2000.0 (2nd Edition, Desk Version) by Wil Tirion & Roger W. Sinnott
Sky Atlas 2000.0 in its second edition offers nearly 90,000 stars, with all positions derived from the Hipparcos database, the most accurate survey ever undertaken. In this Desk Version, the 29 charts show stars and deep-sky objects in black on a white background. The map area is 460 x 330 mm (18 by 13 inches). The charts are printed on heavy paper, and for ease of use they are unbound and boxed. In this format the Atlas will be indispensable as an aid to telescope users who prefer to plan their observing on the desktop.
CLICK HERE
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Sky Atlas 2000.0 in its second edition offers nearly 90,000 stars, with all positions derived from the Hipparcos database, the most accurate survey ever undertaken. In this Desk Version, the 29 charts show stars and deep-sky objects in black on a white background. The map area is 460 x 330 mm (18 by 13 inches). The charts are printed on heavy paper, and for ease of use they are unbound and boxed. In this format the Atlas will be indispensable as an aid to telescope users who prefer to plan their observing on the desktop.
CLICK HERE
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Encyclopedia of Dinosaur
Encyclopedia of Dinosaurs
Philip J. Currie, Kevin Padian Encyclopedia of Dinosaurs
Academic Press | 1997-09-17 | ISBN: 0122268105 | 869 pages | PDF | 68,19 Mb
This book is the most authoritative encyclopedia ever prepared on dinosaurs and dinosaur science. In addition to entries on specific animals such as Tyrannosaurus, Triceratops, and Velociraptor, the Encyclopedia of Dinosaurs covers reproduction, behavior, physiology, and extinction. The book is generously illustrated with many detailed drawings and photographs, and includes color pictures and illustrations that feature interpretations of the best known and most important animals. All alphabetical entries are cross-referenced internally, as well as at the end of each entry. The Encyclopedia includes up-to-date references that encourage the reader to investigate personal interests.
CLICK HERE
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Philip J. Currie, Kevin Padian Encyclopedia of Dinosaurs
Academic Press | 1997-09-17 | ISBN: 0122268105 | 869 pages | PDF | 68,19 Mb
This book is the most authoritative encyclopedia ever prepared on dinosaurs and dinosaur science. In addition to entries on specific animals such as Tyrannosaurus, Triceratops, and Velociraptor, the Encyclopedia of Dinosaurs covers reproduction, behavior, physiology, and extinction. The book is generously illustrated with many detailed drawings and photographs, and includes color pictures and illustrations that feature interpretations of the best known and most important animals. All alphabetical entries are cross-referenced internally, as well as at the end of each entry. The Encyclopedia includes up-to-date references that encourage the reader to investigate personal interests.
CLICK HERE
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Neil Armstrong was not the first man on the moon! (proof inside)
Lyrics to Elvis Presley’s “Lunar Rock” which Armstrong was reading from the LEM while Elvis stepped onto the moon.
Lunar Rock
E. Presley
That’s one small step for man
One giant leap for mankind.
Got no room for the band
But I don’t think they’ll mind.
I’ve got Neil, Buzz, Mike with me
Let’s rock….
(the rest was scratched out in a bought of frustrated writer’s block)
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Scientists discover a nearly Earth-sized planet
HATFIELD, England (AP) — In the search for Earth-like planets, astronomers zeroed in on two places that look awfully familiar to home. One is close to the right size. The other is in the right place. European researchers said they not only found the smallest exoplanet ever, called Gliese 581 e, but realized that a neighboring planet discovered earlier, Gliese 581 d, was in the prime habitable zone for potential life.
"The Holy Grail of current exoplanet research is the detection of a rocky, Earth-like planet in the 'habitable zone,'" said Michel Mayor, an astrophysicist at Geneva University in Switzerland.
An American expert called the discovery of the tiny planet "extraordinary."
Gliese 581 e is only 1.9 times the size of Earth — while previous planets found outside our solar system are closer to the size of massive Jupiter, which NASA says could swallow more than 1,000 Earths.
Gliese 581 e sits close to the nearest star, making it too hot to support life. Still, Mayor said its discovery in a solar system 20 1/2 light years away from Earth is a "good example that we are progressing in the detection of Earth-like planets."
Scientists also discovered that the orbit of planet Gliese 581 d, which was found in 2007, was located within the "habitable zone" — a region around a sun-like star that would allow water to be liquid on the planet's surface, Mayor said.
He spoke at a news conference Tuesday at the University of Hertfordshire during the European Week of Astronomy and Space Science.
Gliese 581 d is probably too large to be made only of rocky material, fellow astronomer and team member Stephane Udry said, adding it was possible the planet had a "large and deep" ocean.
"It is the first serious 'water-world' candidate," Udry said.
Mayor's main planet-hunting competitor, Geoff Marcy of the University of California, Berkeley, praised the find of Gliese 581 e as "the most exciting discovery" so far of exoplanets — planets outside our solar system.
"This discovery is absolutely extraordinary," Marcy told The Associated Press by e-mail, calling the discoveries a significant step in the search for Earth-like planets.
While Gliese 581 e is too hot for life "it shows that nature makes such small planets, probably in large numbers," Marcy commented. "Surely the galaxy contains tens of billions of planets like the small, Earth-mass one announced here."
Nearly 350 planets have been found outside our solar system, but so far nearly every one of them was found to be extremely unlikely to harbor life.
Most were too close or too far from their sun, making them too hot or too cold for life. Others were too big and likely to be uninhabitable gas giants like Jupiter. Those that are too small are highly difficult to detect in the first place.
Both Gliese 581 d and Gliese 581 e are located in constellation Libra and orbit around Gliese 581.
Like other planets circling that star — scientists have discovered four so far — Gliese 581 e was found using the European Southern Observatory's telescope in La Silla, Chile.
The telescope has a special instrument which splits light to find wobbles in different wavelengths. Those wobbles can reveal the existence of other worlds.
"It is great work and shows the potential of this detection method," said Lisa Kaltenegger, an astronomer at the Harvard-Smithsonian Center for Astrophysics.
Associated Press Science Writer Seth Borenstein contributed to this report from Washington.
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"The Holy Grail of current exoplanet research is the detection of a rocky, Earth-like planet in the 'habitable zone,'" said Michel Mayor, an astrophysicist at Geneva University in Switzerland.
An American expert called the discovery of the tiny planet "extraordinary."
Gliese 581 e is only 1.9 times the size of Earth — while previous planets found outside our solar system are closer to the size of massive Jupiter, which NASA says could swallow more than 1,000 Earths.
Gliese 581 e sits close to the nearest star, making it too hot to support life. Still, Mayor said its discovery in a solar system 20 1/2 light years away from Earth is a "good example that we are progressing in the detection of Earth-like planets."
Scientists also discovered that the orbit of planet Gliese 581 d, which was found in 2007, was located within the "habitable zone" — a region around a sun-like star that would allow water to be liquid on the planet's surface, Mayor said.
He spoke at a news conference Tuesday at the University of Hertfordshire during the European Week of Astronomy and Space Science.
Gliese 581 d is probably too large to be made only of rocky material, fellow astronomer and team member Stephane Udry said, adding it was possible the planet had a "large and deep" ocean.
"It is the first serious 'water-world' candidate," Udry said.
Mayor's main planet-hunting competitor, Geoff Marcy of the University of California, Berkeley, praised the find of Gliese 581 e as "the most exciting discovery" so far of exoplanets — planets outside our solar system.
"This discovery is absolutely extraordinary," Marcy told The Associated Press by e-mail, calling the discoveries a significant step in the search for Earth-like planets.
While Gliese 581 e is too hot for life "it shows that nature makes such small planets, probably in large numbers," Marcy commented. "Surely the galaxy contains tens of billions of planets like the small, Earth-mass one announced here."
Nearly 350 planets have been found outside our solar system, but so far nearly every one of them was found to be extremely unlikely to harbor life.
Most were too close or too far from their sun, making them too hot or too cold for life. Others were too big and likely to be uninhabitable gas giants like Jupiter. Those that are too small are highly difficult to detect in the first place.
Both Gliese 581 d and Gliese 581 e are located in constellation Libra and orbit around Gliese 581.
Like other planets circling that star — scientists have discovered four so far — Gliese 581 e was found using the European Southern Observatory's telescope in La Silla, Chile.
The telescope has a special instrument which splits light to find wobbles in different wavelengths. Those wobbles can reveal the existence of other worlds.
"It is great work and shows the potential of this detection method," said Lisa Kaltenegger, an astronomer at the Harvard-Smithsonian Center for Astrophysics.
Associated Press Science Writer Seth Borenstein contributed to this report from Washington.
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PERCayakah ANda Pendaratan D bulan...
Dalam bincang2 tentang pendaratan manusia di Bulan, sering kita terjebak pada "percaya nggak percaya" soal pendaratan itu, tanpa mencoba menoleh lebih jauh tentang sumbangan ilmiah dari peristiwa tersebut.
Mari kita tinjau dua saja diantaranya. Saya mengutipnya dari publikasi American Geophysical Union 1974 dan bulletin Icarus 168 (2004). Yang pertama itu himpunan geofisikawan yang prestisius, sementara yang kedua bulletin ilmiah yang tak kalah prestisiusnya.
Pertama, tentang interior Bulan. Mayoritas pemahaman struktur internal Bulan datang dari data-data kegempaan Bulan (moonquake) yang direkam seismometer-seismometer yang dipasang oleh misi Apollo 11 - 17 (kecuali Apollo 13), yang berfungsi hingga 1977 - 1983 ketika instrumen itu dimatikan karena pasokan listriknya telah menyusut. Misalnya saja, antara 1972 - 1977 tercatat 38 kali gempa Bulan sangat dangkal dengan magnitude hingga 5,5 skala Richter, yang skala guncangannya di Bumi kita sudah melebihi dahsyatnya Gempa Yogya. Ada empat jenis gempa Bulan : gempa sangat dalam (hiposentrum > 700 km, disebabkan oleh gaya pasang surut dalam sistem Bumi-Bulan), gempa tumbukan meteorit, gempa termal (hiposentrum ~ 60 km, disebabkan oleh pemuaian kerak Bulan oleh sinar Matahari setelah 2 minggu menjalani kondisi malam) dan gempa sangat dangkal (hiposentrum 20 - 30 km, disebabkan oleh pemerosotan struktur tepi kawah muda).
Dari data kegempaan ini, yang berdasarkan spektrum gelombang primer (P) yang longitudinal/kompresional dan gelombang sekunder (S) yang transversal, diketahui struktur internal Bulan terbagi ke dalam tiga lapisan : kerak (tebal rata-rata 60 km), selubung/mantel (tebal rata-rata 1.530 km, dari kedalaman 60 km hingga 1.590 km) dan inti (diameter 350 km).
Ada yang unik dari kerak Bulan, dimana pada wajah Bulan yang dekat Bumi (Earthside) secara rata-rata 12 km lebih tipis ketimbang kerak sisi jauh (farside). Ini membuat pusat massa Bulan dan pusat geometrisnya jadi tak berimpit, yakni berselisih 1,8 km, sesuatu yang tidak dijumpai di Bumi dan planet lainnya. Mengapa demikian? Ini terkait dengan evolusinya.
Selubung terdiri dari 3 lapisan : selubung atas, tengah dan bawah. Kini kerak Bulan, selubung atas dan selubung tengah berada pada fase padat, sementara selubung bawah (mulai kedalaman 1.000 km) dan inti fasenya setengah cair. Tebalnya bagian padat ini membuat transfer panas dari interior Bulan ke permukaan terjadi secara konduksi, sehingga magma dari selubung Bulan tidak sanggup bermigrasi ke permukaan baik secara konveksi maupun adveksi. Bandingkan misalnya dengan Bumi, yang bagian padatnya hanya ada di kerak (dengan ketebalan rata-rata 40 km), dialasi selubung yang setengah cair. Ini membuat transfer panas ke kerak Bumi berlangsung secara konveksi dan adveksi, dimana terjadi sirkulasi dalam selubung dan itulah yang menggerakkan lempeng-lempeng tektonik.
Mungkinkah data struktur interior Bulan didapat tanpa harus meletakkan seismometer di permukaan? Secara teknis sangat sulit, dan kalopun bisa hanyalah parsial. Clementine misalnya, pesawat antariksa yang diorbitkan ke Bulan pada 1999, bisa mendeteksi inti Bulan lewat sifat magnetik Bulan (yang sangat lemah) yang ditangkap magnetometer boom-nya yang supersensitif, namun tidak untuk struktur keseluruhan.
Yang kedua, dinamika jarak Bumi-Bulan. Pemahaman ini berasal dari data-data retroreflektor, yakni cermin khusus yang sengaja dipasang di permukaan Bulan dalam misi Apollo 11 - 15 (kecuali Apollo 13) dan dirancang sedemikian rupa sehingga jika dikenai seberkas cahaya maka cahaya itu akan dipantulkan kembali ke sumbernya. Dengan menggunakan Laser, jarak Bumi-Bulan bisa diketahui dengan sangat teliti. Pada dekade 1970-an, ketidakpastian jarak Bumi-Bulan dengan retroreflektor 'hanya' 15 cm, namun di dekade ini telah jauh lebih akurat dengan ketidakpastian hanya 1 - 2 mm saja, sehingga bahkan cukup memadai untuk menguji prinsip ekivalensi yang menjadi batu bata dasar relativitas Einstein.
Dari sini akhirnya diketahui bahwa sumbu mayor orbit Bulan selalu bertambah besar sebanyak 3,6 cm/tahun. Ini terkait dengan gaya pasang surut dalam sistem Bumi-Bulan, dimana implikasi perubahan itu membuat periode rotasi Bumi menjadi sedikit melambat, sementara Bulan semakin menjauh. Bulan akan terus menjauh dari Bumi sedikit demi sedikit hingga sampai di region dimana gaya pasang surut sistem Bulan-Matahari lebih dominan dan pada saat itu Bulan akan lebih dikontrol oleh gravitasi Matahari.
Jika diekstrapolasikan mundur ke belakang, mudah ditebak bahwa Bulan pernah bergabung jadi satu dengan Bumi. Pemisahan (fission) Bumi - Bulan diperkirakan terjadi pada masa awal tata surya ketika proto-Bumi dihantam benda langit seukuran Mars, yang membuat sebagian selubung Bumi terlepas ke angkasa dan terkondensasi sendiri hingga membentuk Bulan. Ini konsisten dengan data densitas rata-rata Bulan (yang besarnya 3,35 g/cc atau sama dengan densitas selubung Bumi) dan keberadaan mineral ilmenit (FeTiO3) di batuan Bulan yang 10 kali lipat lebih tinggi dari batuan Bumi, sementara konsentrasi ilmenit setinggi itu di Bumi hanya ditemukan pada selubung (berdasarkan data seismik). Kesimpulan ini juga ditunjang rekaman fosil stromatolit di Bumi dari zaman Devon (400 juta tahun silam), yang jelas menunjukkan bahwa setahun Bumi saat itu terdiri dari 400 hari (bandingkan dengan 365 hari di masa sekarang).
Mungkinkah menentukan pertambahan jarak 3,6 cm/tahun ini tanpa meletakkan retroreflektor di Bulan? Amat sangat sulit, untuk tidak mengatakan tidak mungkin. Dengan gelombang radar jelas tidak mungkin, karena ketidakpastiannya cukup besar (dalam orde beberapa ratus hingga beberapa km). Sementara menggunakan satelit, misalnya, kita harus memperhitungkan efek relativitas umum akibat pelengkungan kurvatur ruang-waktu di dekat Bumi dan juga di dekat Bulan, yang membuat deteksi posisi satelit bisa bergeser beberapa km dari titik yang sebenarnya.
Dari dua hal itu saja, bisa dilihat bahwa misi Apollo ke Bulan membuat pengetahuan kita tentang Bulan menjadi berlipat ganda secara eksponensial.
Saya percaya Wernher von Braun, Farouk el-Baz dan orang-orang pinter di balik misi Apollo sejatinya takkan mempersoalkan skeptisme dan hiruk pikuk tentang benar tidaknya pendaratan itu. Sebab ini bukan wilayah "percaya nggak percaya", namun lebih pada bagaimana mengkajinya, mengkritisinya dan sekaligus memaparkan antitesisnya (kalo ada) dalam metodologi yang bisa dipercaya. Sebab pendaratan itu sebuah peristiwa ilmiah, bukan dogma. Dan sejauh ini pihak2 yang menganggap pendaratan di Bulan sebagai hoax gagal untuk menjelaskan (secara ilmiah pula) bagaimana pengetahuan kita tentang satelit Bumi itu menjadi berlipat ganda pasca dekade 1960-an. Terlebih data2 dari misi Apollo tetap menunjukkan konsistensinya jika dibandingkan dengan misi2 antariksa yang lebih kemudian, seperti Lunar Prospector 1996, Clementine 1999, Magellan 1989 dan Cassini 1997 (meski dua yang terakhir tadi sebenarnya hanya memanfaatkan gravitasi Bulan untuk pergi ke planet lain).
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Mari kita tinjau dua saja diantaranya. Saya mengutipnya dari publikasi American Geophysical Union 1974 dan bulletin Icarus 168 (2004). Yang pertama itu himpunan geofisikawan yang prestisius, sementara yang kedua bulletin ilmiah yang tak kalah prestisiusnya.
Pertama, tentang interior Bulan. Mayoritas pemahaman struktur internal Bulan datang dari data-data kegempaan Bulan (moonquake) yang direkam seismometer-seismometer yang dipasang oleh misi Apollo 11 - 17 (kecuali Apollo 13), yang berfungsi hingga 1977 - 1983 ketika instrumen itu dimatikan karena pasokan listriknya telah menyusut. Misalnya saja, antara 1972 - 1977 tercatat 38 kali gempa Bulan sangat dangkal dengan magnitude hingga 5,5 skala Richter, yang skala guncangannya di Bumi kita sudah melebihi dahsyatnya Gempa Yogya. Ada empat jenis gempa Bulan : gempa sangat dalam (hiposentrum > 700 km, disebabkan oleh gaya pasang surut dalam sistem Bumi-Bulan), gempa tumbukan meteorit, gempa termal (hiposentrum ~ 60 km, disebabkan oleh pemuaian kerak Bulan oleh sinar Matahari setelah 2 minggu menjalani kondisi malam) dan gempa sangat dangkal (hiposentrum 20 - 30 km, disebabkan oleh pemerosotan struktur tepi kawah muda).
Dari data kegempaan ini, yang berdasarkan spektrum gelombang primer (P) yang longitudinal/kompresional dan gelombang sekunder (S) yang transversal, diketahui struktur internal Bulan terbagi ke dalam tiga lapisan : kerak (tebal rata-rata 60 km), selubung/mantel (tebal rata-rata 1.530 km, dari kedalaman 60 km hingga 1.590 km) dan inti (diameter 350 km).
Ada yang unik dari kerak Bulan, dimana pada wajah Bulan yang dekat Bumi (Earthside) secara rata-rata 12 km lebih tipis ketimbang kerak sisi jauh (farside). Ini membuat pusat massa Bulan dan pusat geometrisnya jadi tak berimpit, yakni berselisih 1,8 km, sesuatu yang tidak dijumpai di Bumi dan planet lainnya. Mengapa demikian? Ini terkait dengan evolusinya.
Selubung terdiri dari 3 lapisan : selubung atas, tengah dan bawah. Kini kerak Bulan, selubung atas dan selubung tengah berada pada fase padat, sementara selubung bawah (mulai kedalaman 1.000 km) dan inti fasenya setengah cair. Tebalnya bagian padat ini membuat transfer panas dari interior Bulan ke permukaan terjadi secara konduksi, sehingga magma dari selubung Bulan tidak sanggup bermigrasi ke permukaan baik secara konveksi maupun adveksi. Bandingkan misalnya dengan Bumi, yang bagian padatnya hanya ada di kerak (dengan ketebalan rata-rata 40 km), dialasi selubung yang setengah cair. Ini membuat transfer panas ke kerak Bumi berlangsung secara konveksi dan adveksi, dimana terjadi sirkulasi dalam selubung dan itulah yang menggerakkan lempeng-lempeng tektonik.
Mungkinkah data struktur interior Bulan didapat tanpa harus meletakkan seismometer di permukaan? Secara teknis sangat sulit, dan kalopun bisa hanyalah parsial. Clementine misalnya, pesawat antariksa yang diorbitkan ke Bulan pada 1999, bisa mendeteksi inti Bulan lewat sifat magnetik Bulan (yang sangat lemah) yang ditangkap magnetometer boom-nya yang supersensitif, namun tidak untuk struktur keseluruhan.
Yang kedua, dinamika jarak Bumi-Bulan. Pemahaman ini berasal dari data-data retroreflektor, yakni cermin khusus yang sengaja dipasang di permukaan Bulan dalam misi Apollo 11 - 15 (kecuali Apollo 13) dan dirancang sedemikian rupa sehingga jika dikenai seberkas cahaya maka cahaya itu akan dipantulkan kembali ke sumbernya. Dengan menggunakan Laser, jarak Bumi-Bulan bisa diketahui dengan sangat teliti. Pada dekade 1970-an, ketidakpastian jarak Bumi-Bulan dengan retroreflektor 'hanya' 15 cm, namun di dekade ini telah jauh lebih akurat dengan ketidakpastian hanya 1 - 2 mm saja, sehingga bahkan cukup memadai untuk menguji prinsip ekivalensi yang menjadi batu bata dasar relativitas Einstein.
Dari sini akhirnya diketahui bahwa sumbu mayor orbit Bulan selalu bertambah besar sebanyak 3,6 cm/tahun. Ini terkait dengan gaya pasang surut dalam sistem Bumi-Bulan, dimana implikasi perubahan itu membuat periode rotasi Bumi menjadi sedikit melambat, sementara Bulan semakin menjauh. Bulan akan terus menjauh dari Bumi sedikit demi sedikit hingga sampai di region dimana gaya pasang surut sistem Bulan-Matahari lebih dominan dan pada saat itu Bulan akan lebih dikontrol oleh gravitasi Matahari.
Jika diekstrapolasikan mundur ke belakang, mudah ditebak bahwa Bulan pernah bergabung jadi satu dengan Bumi. Pemisahan (fission) Bumi - Bulan diperkirakan terjadi pada masa awal tata surya ketika proto-Bumi dihantam benda langit seukuran Mars, yang membuat sebagian selubung Bumi terlepas ke angkasa dan terkondensasi sendiri hingga membentuk Bulan. Ini konsisten dengan data densitas rata-rata Bulan (yang besarnya 3,35 g/cc atau sama dengan densitas selubung Bumi) dan keberadaan mineral ilmenit (FeTiO3) di batuan Bulan yang 10 kali lipat lebih tinggi dari batuan Bumi, sementara konsentrasi ilmenit setinggi itu di Bumi hanya ditemukan pada selubung (berdasarkan data seismik). Kesimpulan ini juga ditunjang rekaman fosil stromatolit di Bumi dari zaman Devon (400 juta tahun silam), yang jelas menunjukkan bahwa setahun Bumi saat itu terdiri dari 400 hari (bandingkan dengan 365 hari di masa sekarang).
Mungkinkah menentukan pertambahan jarak 3,6 cm/tahun ini tanpa meletakkan retroreflektor di Bulan? Amat sangat sulit, untuk tidak mengatakan tidak mungkin. Dengan gelombang radar jelas tidak mungkin, karena ketidakpastiannya cukup besar (dalam orde beberapa ratus hingga beberapa km). Sementara menggunakan satelit, misalnya, kita harus memperhitungkan efek relativitas umum akibat pelengkungan kurvatur ruang-waktu di dekat Bumi dan juga di dekat Bulan, yang membuat deteksi posisi satelit bisa bergeser beberapa km dari titik yang sebenarnya.
Dari dua hal itu saja, bisa dilihat bahwa misi Apollo ke Bulan membuat pengetahuan kita tentang Bulan menjadi berlipat ganda secara eksponensial.
Saya percaya Wernher von Braun, Farouk el-Baz dan orang-orang pinter di balik misi Apollo sejatinya takkan mempersoalkan skeptisme dan hiruk pikuk tentang benar tidaknya pendaratan itu. Sebab ini bukan wilayah "percaya nggak percaya", namun lebih pada bagaimana mengkajinya, mengkritisinya dan sekaligus memaparkan antitesisnya (kalo ada) dalam metodologi yang bisa dipercaya. Sebab pendaratan itu sebuah peristiwa ilmiah, bukan dogma. Dan sejauh ini pihak2 yang menganggap pendaratan di Bulan sebagai hoax gagal untuk menjelaskan (secara ilmiah pula) bagaimana pengetahuan kita tentang satelit Bumi itu menjadi berlipat ganda pasca dekade 1960-an. Terlebih data2 dari misi Apollo tetap menunjukkan konsistensinya jika dibandingkan dengan misi2 antariksa yang lebih kemudian, seperti Lunar Prospector 1996, Clementine 1999, Magellan 1989 dan Cassini 1997 (meski dua yang terakhir tadi sebenarnya hanya memanfaatkan gravitasi Bulan untuk pergi ke planet lain).
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hajarol aswad + kaabah
Neil Amstrong telah membuktikan bahwa kota Mekah adalah pusat dari planet Bumi. Fakta ini telah di diteliti melalui sebuah penelitian
Ilmiah. Ketika Neil Amstrong untuk pertama kalinya melakukan perjalanan ke luar angkasa dan mengambil gambar planet Bumi, di berkata : "Planet
Bumi ternyata menggantung di area yang sangat gelap, siapa yang menggantungnya ?."
>
> Para astronot telah menemukan bahwa planet Bumi itu mengeluarkan semacam radiasi, secara resmi mereka mengumumkannya di Internet,
> tetapi sayang nya 21 hari kemudian website tersebut raib yang sepertinya ada asalan tersembunyi dibalik penghapusan website tersebut.
> Setelah melakukan penelitian lebih lanjut, ternyata radiasi tersebut berpusat di kota Mekah, tepatnya berasal dari Ka'Bah. Yang mengejutkan
> adalah radiasi tersebut bersifat infinite ( tidak berujung ), hal ini terbuktikan ketika mereka mengambil foto planet Mars, radiasi tersebut
> masih berlanjut terus. Para peneliti Muslim mempercayai bahwa radiasi ini memiliki karakteristik dan menghubungkan antara Ka'Bah di di
> planet Bumi dengan Ka'bah di alam akhirat.
>
> Di tengah-tengah antara kutub utara dan kutub selatan, ada suatu area yang bernama 'Zero Magnetism Area', artinya adalah apabila kita
> mengeluarkan kompas di area tersebut, maka jarum kompas tersebut tidak akan bergerak sama sekali karena daya tarik yang sama besarnya antara
> kedua kutub.
> Itulah sebabnya jika seseorang tinggal di Mekah, maka ia akan hidup lebih lama, lebih sehat, dan tidak banyak dipengaruhi oleh banyak
> kekuatan gravitasi. Oleh sebab itu lah ketika kita mengelilingi Ka'Bah, maka seakan-akan diri kita di-charged ulang oleh suatu energi
> misterius dan ini adalah fakta yang telah dibuktikan secara ilmiah.
> Penelitian lainnya mengungkapkan bahwa batu Hajar Aswad merupakan batu tertua di dunia dan juga bisa mengambang di air. Di sebuah musium di
> negara Inggris, ada tiga buah potongan batu tersebut ( dari Ka'Bah ) dan pihak musium juga mengatakan bahwa bongkahan batu-batu tersebut
> bukan berasal dari sistem tata surya kita.
> Dalam salah satu sabdanya, Rasulullah SAW bersabda, "Hajar Aswad itu diturunkan dari surga, warnanya lebih putih daripada susu, dan
> dosa-dosa anak cucu Adamlah yang menjadikannya hitam. ( Jami al-Tirmidzi al-Hajj (877) )
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Ilmiah. Ketika Neil Amstrong untuk pertama kalinya melakukan perjalanan ke luar angkasa dan mengambil gambar planet Bumi, di berkata : "Planet
Bumi ternyata menggantung di area yang sangat gelap, siapa yang menggantungnya ?."
>
> Para astronot telah menemukan bahwa planet Bumi itu mengeluarkan semacam radiasi, secara resmi mereka mengumumkannya di Internet,
> tetapi sayang nya 21 hari kemudian website tersebut raib yang sepertinya ada asalan tersembunyi dibalik penghapusan website tersebut.
> Setelah melakukan penelitian lebih lanjut, ternyata radiasi tersebut berpusat di kota Mekah, tepatnya berasal dari Ka'Bah. Yang mengejutkan
> adalah radiasi tersebut bersifat infinite ( tidak berujung ), hal ini terbuktikan ketika mereka mengambil foto planet Mars, radiasi tersebut
> masih berlanjut terus. Para peneliti Muslim mempercayai bahwa radiasi ini memiliki karakteristik dan menghubungkan antara Ka'Bah di di
> planet Bumi dengan Ka'bah di alam akhirat.
>
> Di tengah-tengah antara kutub utara dan kutub selatan, ada suatu area yang bernama 'Zero Magnetism Area', artinya adalah apabila kita
> mengeluarkan kompas di area tersebut, maka jarum kompas tersebut tidak akan bergerak sama sekali karena daya tarik yang sama besarnya antara
> kedua kutub.
> Itulah sebabnya jika seseorang tinggal di Mekah, maka ia akan hidup lebih lama, lebih sehat, dan tidak banyak dipengaruhi oleh banyak
> kekuatan gravitasi. Oleh sebab itu lah ketika kita mengelilingi Ka'Bah, maka seakan-akan diri kita di-charged ulang oleh suatu energi
> misterius dan ini adalah fakta yang telah dibuktikan secara ilmiah.
> Penelitian lainnya mengungkapkan bahwa batu Hajar Aswad merupakan batu tertua di dunia dan juga bisa mengambang di air. Di sebuah musium di
> negara Inggris, ada tiga buah potongan batu tersebut ( dari Ka'Bah ) dan pihak musium juga mengatakan bahwa bongkahan batu-batu tersebut
> bukan berasal dari sistem tata surya kita.
> Dalam salah satu sabdanya, Rasulullah SAW bersabda, "Hajar Aswad itu diturunkan dari surga, warnanya lebih putih daripada susu, dan
> dosa-dosa anak cucu Adamlah yang menjadikannya hitam. ( Jami al-Tirmidzi al-Hajj (877) )
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Unusual Micrometeorite Found in Antarctica
A miniature meteorite unlike any other has been discovered in Antarctica. The tiny rock, known as MM40, is the first achondritic basaltic micrometeorite ever found on Earth. Detailed analysis shows it has an unusual chemical composition the researchers say raises questions about where it originated in the Solar System and how it was created. “We have basaltic meteorites that are thought to come from an asteroid called 4 Vesta and we also have basaltic meteorites from the Moon and Mars,” said Dr. Caroline Smith, curator of meteorites at the Natural History Museum, London “But MM04’s chemistry does not match any of those places. It has to be from somewhere else.”
MM40 is only 150 microns across as its widest point, (.0059055 inches) or about as big as the period at the end of this sentence.
Chondritic meteorites were formed during the the Solar System’s early days before material had accreted into planets. They have not been altered by the melting and re-crystalisation that takes place during planetary formation and erosional forces similar to what Earth rocks undergo.
Achondritic meteorites, by contrast, were formed when the Solar System’s planets were coming into being. The substances in such meteorites and the processes they have undergone can give clues about how the larger bodies were formed.
The research team, led by Matthieu Gounelle from the Laboratory of Mineralogy and Cosmochemistry at the French Natural History Museum, says the discovery of this new type of basaltic meteorite expands the solar system inventory of planetary crusts. “The parent asteroid of MM40 has undergone extensive metamorphism,” the researchers write, “which ended no earlier than 7.9 million years after solar system formation. Numerical simulations of dust transport dynamics suggest that MM40 might originate from one of the recently discovered basaltic asteroids that are not members of the Vesta family.”
While its ultimate origins are a mystery it does have implications for the ways that astrochemists thought planets could be formed. The analysis of MM04 showed that the “inventory” of such processes must be expanded, said Dr. Smith.
“Micrometeorites are often seen as the ‘poor man’s space probe’,” she said. “They land on Earth fortuitously and we do not have to spend millions of dollars or euros on a robotic mission to get them.”
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MM40 is only 150 microns across as its widest point, (.0059055 inches) or about as big as the period at the end of this sentence.
Chondritic meteorites were formed during the the Solar System’s early days before material had accreted into planets. They have not been altered by the melting and re-crystalisation that takes place during planetary formation and erosional forces similar to what Earth rocks undergo.
Achondritic meteorites, by contrast, were formed when the Solar System’s planets were coming into being. The substances in such meteorites and the processes they have undergone can give clues about how the larger bodies were formed.
The research team, led by Matthieu Gounelle from the Laboratory of Mineralogy and Cosmochemistry at the French Natural History Museum, says the discovery of this new type of basaltic meteorite expands the solar system inventory of planetary crusts. “The parent asteroid of MM40 has undergone extensive metamorphism,” the researchers write, “which ended no earlier than 7.9 million years after solar system formation. Numerical simulations of dust transport dynamics suggest that MM40 might originate from one of the recently discovered basaltic asteroids that are not members of the Vesta family.”
While its ultimate origins are a mystery it does have implications for the ways that astrochemists thought planets could be formed. The analysis of MM04 showed that the “inventory” of such processes must be expanded, said Dr. Smith.
“Micrometeorites are often seen as the ‘poor man’s space probe’,” she said. “They land on Earth fortuitously and we do not have to spend millions of dollars or euros on a robotic mission to get them.”
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Israeli Jews (fuck) bless the sun in rare 28-year prayer
Tens of thousands of Jewish faithful turned out before sunrise on Wednesday in front of the Wailing Wall in Jerusalem and elsewhere in the country to bless the sun in a prayer said once every 28 years.
Dressed in white prayer shawls, men and women, adults and children filled the plaza in front of the wall, Judaism's holiest site, and crowded onto nearby rooftops to catch a glimpse of the sun rising over the Holy City.
As the faithful swayed back and forth in prayer, the area filled with the din of the Birkat Hakhama prayer.
Elsewhere around Israel and the occupied West Bank, tens of thousands of observant Jews sought out hilltops and rooftops to catch the first rays of the sun to recite the prayer.
Birkat Hakhama is said as the sun comes up to mark what according to Jewish tradition is the sun's return to its position at the moment that the universe was created 5,769 years ago. It returns to the spot once every 28 years.
The prayer has special significance this year because it coincides with the start of the Passover holiday, one of Judaism's most important, at sundown on Wednesday.
The Wailing Wall, also called the Western Wall, sits below the Al-Aqsa Mosque compound, Islam's third-holiest place.
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Dressed in white prayer shawls, men and women, adults and children filled the plaza in front of the wall, Judaism's holiest site, and crowded onto nearby rooftops to catch a glimpse of the sun rising over the Holy City.
As the faithful swayed back and forth in prayer, the area filled with the din of the Birkat Hakhama prayer.
Elsewhere around Israel and the occupied West Bank, tens of thousands of observant Jews sought out hilltops and rooftops to catch the first rays of the sun to recite the prayer.
Birkat Hakhama is said as the sun comes up to mark what according to Jewish tradition is the sun's return to its position at the moment that the universe was created 5,769 years ago. It returns to the spot once every 28 years.
The prayer has special significance this year because it coincides with the start of the Passover holiday, one of Judaism's most important, at sundown on Wednesday.
The Wailing Wall, also called the Western Wall, sits below the Al-Aqsa Mosque compound, Islam's third-holiest place.
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