Agendaku

Salah satu target penting yang harus kulaksanakan dalam 3 bulan terakhir ini adalah mulai kembali melaksanakan riset fisika. Sudah lama sekali rasanya aku tidak melakukan hal penting. 

Kerinduan akan kembali menggeluti fisika teoretis nampaknya kembali menyapa. Bagaimanapun kita adalah produk dari pendidikan dan pengalaman kita, sehingga melupakan latar belakang keilmuwan kita sungguh sulit. 

Setelah survey-survey nampaknya muncul satu topik menarik yang hendak aku risetkan di bidang fisika teoretis, yaitu soal geometri relativitas umum dari pendekatan pseudo-kompleks.

Temuan Baru di Pluto

'Snakeskin' Pluto revealed in planetary close-up

Intriguing ridges add to dwarf planet's geological mysteries.

• Alexandra Witze

24 September 2015

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“What is that?” planetary scientist Barbara Cohen gasped, marvelling at the latest images of Pluto released on 24 September.
Cohen, of NASA's Marshall Space Flight Center in Huntsville, Alabama, is not alone. It is a question nearly every planetary specialist is asking with each release of pictures from NASA's New Horizons spacecraft, which flew past Pluto and its moons in July. The latest images — the most-detailed colour shots yet downlinked to Earth — show a bizarre 'snakeskin' terrain, wrinkled with ridges and smudged with rust-coloured material.

NASA/JHUAPL/SWRI

Ridges cover a mountain range known informally as Tartarus Dorsa.

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Many of the ridges run in parallel directions, suggesting that they were formed by some sort of overarching geological influence — perhaps wind. The corrugated ridges seem to be tens of kilometres long. “These aren't little ripples — these are giant features,” says Alex Parker, a member of the New Horizons science team at the Southwest Research Institute in Boulder, Colorado.

Nature Special: Pluto and Ceres

The photos come from the colour camera aboard New Horizons's Ralph instrument, and are enhanced to bring out compositional differences between materials on the dwarf planet's surface.
So far, Pluto has turned out to be strikingly active for an icy world 5 billion kilometres from the Sun. Nitrogen glaciers swirl around the base of towering mountains, which are held up by the sheer rigidity of ice frozen at about −235 °C, 38 degrees above absolute zero.
Another image reveals Pluto's surface in the greatest detail yet, with resolutions down to 250 metres. Chunks of mountain blocks, coated with what are probably dark-red hydrocarbon molecules, are surrounded by ice that flows through a basin known as Sputnik Planum.

NASA/JHUAPL/SWRI

Blocky structures seen here may be mountains — or icebergs.

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Seen from above, the ice seems to close in around the jagged mountains, resembling the embayments in the sea ice that surrounds Antarctica. But some of these 'mountains' might in fact be icebergs decoupled from the bedrock beneath.
And viewed at close range, even the smoothest ice surfaces turn out to be remarkably complex, with a pitted or dimpled texture that could reflect ices subliming away into the atmosphere. These vast plains might represent the tops of thick layers of ice that flow and churn from within, tracing polygonal structures on the surface.

NASA/JHUAPL/SWRI

Pebbled plains surround ice mountains in this patch of Pluto's surface.

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Some of the mountain ranges seem to show darker layers of material in the sides of steep cliffs. Elsewhere, material piles up between the peaks, including a spot that looks like an icy pond.
“This is all bizarre,” says Parker. “There are a lot of new questions we're going to be able to ask because of these images, and we're going to be able to answer some of them.”
Next month, New Horizons will burn its engines in a series of manoeuvres to set it on course to fly past a second, even more distant world in 2019.

Nature

doi:10.1038/nature.2015.18433

Pengamatan Resolusi Tinggi

ALMA debuts its high-resolution results

Apr 17, 2015 1 comment

Cincin Api: Pengamatan dengan Resolusi Tertinggi ALMA

Scientific results of the highest resolution observations yet attempted by the Atacama Large Millimeter/submillimeter Array (ALMA) telescope are described in four papers to be published this month in Astrophysical Journal Letters. The observations were part of a campaign to test ALMA's capabilities when run in its long-baseline configuration, and the result is stunning images and data for five astronomical objects. These include the planet-forming disc of HL Tau, the tumbling asteroid Juno, and a lensed galaxy 12 billion light-years away. These results are not only rich with new insights, but they also give us a sense of the incredible capabilities that ALMA will provide in the future.

ALMA is an array of 12 m- and 7 m-diameter antennas that observe the cosmos at millimetre/submillimetre wavelengths. The antennas work together to function as an interferometer, and this allows the signals from each of the antennas to be combined to simulate a telescope the size of the distance between the individual units. The array works like a zoom lens on a camera: the antennas can be repositioned so that the baseline of the simulated telescope is as small as 150 m or as large as 15 km across.

Expecting the unexpected

ALMA's capabilities in its wavelength regime are revolutionary. The array is the largest and most sensitive millimetre/submillimetre instrument in the world, and its resolution is 10 times better than even the Hubble Space Telescope. As Anneila Sargent, chair of the ALMA board while the array was being built, predicted in 2008, "We know that every time in the past that a new wavelength region has been opened up, as ALMA will do, we have been surprised by entirely unexpected discoveries that significantly changed our understanding of the universe. We also expect the unexpected from ALMA."
In its smaller configurations, ALMA can study the large-scale structure of cold gas and dust in the universe – and this is how the array has been used since it began its first early-science operations in 2011. But now, ALMA is beginning to test its long-baseline configuration, in which it is able to make its highest resolution observations and study the small-scale structure of objects in detail.
ALMA's Long Baseline Campaign, which ran in late 2014, observed five targets using 22–36 antennas arranged with a baseline of up to the maximum 15 km. The targets were specifically selected to push the limits of ALMA's capabilities: each target has a small angular size (less than two arcseconds) with a fine-scale structure that had been largely unresolved in previous observations made with other telescopes. Two of the targets, the variable star Mira and the active galaxy 3C138, were primarily used for calibration and comparisons of ALMA data with those of other telescopes. The remaining three targets not only demonstrated ALMA's capabilities, but also resulted in new science discoveries.

Possible planets: this protoplanetary disc surrounds HL Tau

The first discovery involves HL Tau, which is a young star surrounded by a protoplanetary disc – a disc of gas and dust from which planets can be born. ALMA's detailed observations of this region revealed a remarkable structure within the disc: a series of light and dark concentric rings indicative of planets caught in the act of formation. Studying this system is allowing scientists to better understand how multi-planet solar systems, like our own, form and evolve.
Juno, which is one of the largest asteroids in our solar system's main asteroid belt, is the subject of the second discovery. ALMA's observations of Juno were made when the asteroid was approximately 295 million kilometres from Earth. The 10 images ALMA took have been stitched together into the brief animation shown below, which shows the asteroid tumbling through space as it orbits the Sun. ALMA's observations are not of reflected light, but rather of the millimetre-wavelength light emitted by the asteroid itself. The resolution of these images is good enough to study the shape and even some surface features of the asteroid – something that is unprecedented for this wavelength.
The final discovery concerns the star-forming galaxy SDP.81, which is so far from Earth that the light we see was emitted when the universe was only 15% of its current age. The galaxy is only visible because of a fortuitous alignment between it and a nearby foreground galaxy. The gravity of the foreground galaxy acts as a lens and bends the light from SDP.81 into a highly magnified cosmic ring. The combination of this lucky alignment and ALMA's high resolution gives scientists a spectacularly detailed view of this distant galaxy, allowing them to study the actual shape of the galaxy and motion within it. This is ALMA's highest resolution observation so far, and is described by Alma astronomers as being "about the same as seeing the rim of a basketball hoop atop the Eiffel Tower from the observing deck of the Empire State Building".
The observations from ALMA's first test of its long baseline clearly demonstrate that exciting times are ahead as scientists gear-up for the next cycle of observations. "It takes a combination of ALMA's high resolution and high sensitivity to unlock these otherwise hidden details of the early universe," says ALMA director Pierre Cox. "These results open a new frontier in astronomy, and prove that ALMA can indeed deliver on its promise of transformational science."

About the author

Susanna Kohler is Science Highlights editor at the American Astronomical Society

Teka Teki Ruwet

Silahkan Pahami pertanyaan soal dibawah ini:

Ada 5 buah rumah yang masing-masing memiliki warna berbeda. setiap rumah dihuni oleh satu orang pria dengan kebangsaan yang berbeda-beda. Setiap penghuni menyukai satu jenis minuman tertentu, mendengarkan satu jenis musik tertentu dan memelihara satu jenis hewan tertentu.
Tidak ada satupun dari kelima orang tersebut yang meminum minuman yang sama, mendengarkan jenis musik yang sama dan memelihara hewan yang sama pula seperti penghuni lainnya.

Pertanyaan:
Siapakah yang memelihara ikan? Bagaimana susunan lengkapnya (kewarganegaraan, warna rumah, minuman, musik dan hewan peliharaan) kelima pria tersebut?

Petunjuk:

1. Orang Inggris tinggal dalam rumah berwarna merah
2. Orang Swedia memelihara anjing
3. Orang Denmark senang minum teh
4. Rumah berwarna hijau terletak tepat di sebelah kiri rumah berwarna putih
5. Penghuni rumah berwarna hijau senang minum kopi
6. Orang yang mendengarkan musik Jazz memelihara burung
7. Penghuni rumah yang terletak di tengah-tengah senang minum susu
8. Penghuni rumah berwarna kuning senang mendengarkan musik jenis pop
9. Orang Norwegia tinggal di rumah pertama
10. Orang yang mendengarkan musik jenis klasik tinggal di sebelah orang yang memelihara kucing.
11. Orang yang memelihara kuda tinggal di sebelah orang yang mendengarkan musik pop
12. Orang yang mendengarkan musik rock senang minum coklat
13. Di sebelah rumah berwarna biru tinggal orang Norwegia
14. Orang Jerman senang mendengarkan musik hip hop
15. Orang yang mendengarkan musik klasik bertetangga dengan orang yang minum air

Solusi:
Pertama dari kondisi nomor 9 orang norwegia tinggal di rumah pertama, dan dari no 14 sampingnya rumah biru dan nomor 8 rumah tengah minum susu kita buat kondisi awal sebagai berikut.

Selanjutnya nomor 4 dan 5 rumah hijau di kiri rumah putih dan rumah hijau minum kopi, berarti butuh dua slot warna kosong dengan slot kiri minumannya kosong, pasang saja di tempat yang bisa seperti ini

Dari nomor 1 diberitakan bahwa orang inggris rumahnya merah. Yang negara dan warnanya masih kosong ya di tengah. Lalu dari nomor 7 rumah kuning menghisap dunhill, yang belum dicat hanya rumah orang norwegia, sok atuh. Lalu di nomor 11 dimana disamping perokok dunhill ada pemelihara kuda

Sekarang agak sedikit rumit, masih ada swedia, denmark, dan jerman. Si swedia pelihara anjing, si denmark minum the dan jerman merokok prince. Apa yang akan kita lakukan?? kita lihat di nomor 12 perokok blue master minum bir, dan yang slot rokok dan minumnya kosong hanya swedia, maka orang swedia minum bir, merokok blu master dan memelihara anjing, otomatis yang ketiga slot ini masih kosong hanya di paling ujung yaitu rumah putih

Selanjutnya tidak terlalu sulit, orang denmark minum the, bukan kopi jadi dia tinggal di rumah biru dan memelihara kuda. Sementara orang jerman merokok Prince, yang masih kosong hanya peminum kopi di rumah hijau.

Langkah mudah selanjutnya adalah perokok pall mall memelihara burung di nomor 6, dan ternyata dia orang inggris karena di slot yang kosong rokok dan hewannya hanya disitu

Langkah terakhir nomor 10 perokok blend tinggal di samping pemilik kucing dan dia juga bertetangga dengan peminum air pada nomor 15. Perokok blends ini tak lain adalah orang denmark, dan peminum air yang memelihara kucing tak lain orang norwegia.

Bagaimana Mengerti?

apakah anda termasuk 2% dari penduduk yang mengetahui jawabannya

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Last edited by lemur; 8 October 2014 at 11:46.