Proses Terbentuknya/Terjadinya Hujan Alami Dan Buatan - Ilmu Pengetahuan Fisika
Hujan adalah peristiwa turunnya air dari langit ke bumi. Awalnya air hujan berasal dari air dari bumi seperti air laut, air sungai, air danau, air waduk, air rumpon, air sawah, air comberan, air susu, air jamban, air kolam, air ludah, dan lain sebagainya. Selain air yang berbentuk fisik, air yang menguap ke udara juga bisa berasal dari tubuh manusia, binatang, tumbuh-tumbuhan, serta benda-benda lain yang mengandung air.
Air-air tersebut umumnya mengalami proses penguapan atau evaporasi akibat adanya bantuan panas matahari. Air yang menguap / menjadi uap melayang ke udara dan akhirnya terus bergerak menuju langit yang tinggi bersama uap-uap air yang lain. Di langit yang tinggi uap tersebut mengalami proses pemadatan atau kondensasi sehingga membentuk awan. Dengan bantuan angin awan-awan tersebut dapat bergerak kesana-kemari baik vertikal, horizontal dan diagonal.
Akibat angin atau udara yang bergerak pula awan-awah saling bertemu dan membesar menuju langit / atmosfir bumi yang suhunya rendah atau dingin dan akhirnya membentuk butiran es dan air. Karena berat dan tidak mampu ditopang angin akhirnya butiran-butiran air atau es tersebut jatuh ke permukaan bumi (proses presipitasi). Karena semakin rendah suhu udara semakin tinggi maka es atau salju yang terbentuk mencair menjadi air, namun jika suhunya sangat rendah maka akan turun tetap sebagai salju.
Hujan tidak hanya turun berbentuk air dan es saja, namun juga bisa berbentuk embun dan kabut. Hujan yang jatuh ke permukaan bumi jika bertemu dengan udara yang kering, sebagian ujan dapat menguap kembali ke udara. Bentuk air hujan kecil adalah hampir bulat, sedangkan yang besar lebih ceper seperti burger, dan yang lebih besar lagi berbentuk payung terjun. Hujan besar memiliki kecepatan jatuhnya air yang tinggi sehingga terkadang terasa sakit jika mengenai anggota badan kita.
Hujan buatan adalah hujan yang dibuat oleh campur tangan manusia dengan membuat hujan dari bibit-bibit awan yang memiliki kandungan air yang cukup, memiliki kecepatan angin rendah yaitu sekitar di bawah 20 knot, serta syarat lainnya. Ujan buatan dibuat dengan menaburkan banyak garam khusus yang halus dan dicampur bibit / seeding ke awan agar mempercepat terbentuknya awan jenuh. Untuk menyemai / membentuk hujan deras, biasanya dibutuhkan garam sebanyak 3 ton yang disemai ke awan potensial selama 30 hari. Hujan buatan saja bisa gagal dibuat atau jatuh di tempat yang salah serta memakan biaya yang besar dalam pembuatannya.
Juhan buatan umumnya diciptakan dengan tujuan untuk membantu daerah yang sangat kering akibat sudah lama tidak turun hujan sehingga dapat mengganggu kehidupan di darat mulai dari sawah kering, gagal panen, sumur kering, sungai / danau kering, tanah retak-retak, kesulitan air bersih, hewan dan tumbuhan pada mati dan lain sebagainya. Dengan adanya hujan buatan diharapkan mampu menyuplai kebutuhan air makhluk hidup di bawahnya dan membuat masyarakat hidup bahagia dan sejahtera.
Hujan yang berlebih pada suatu lokasi dapat menimbulkan bencana pada kehidupan di bawahnya. Banjir dan tanah longsor adalah salah satu akibat dari hujan yang berlebihan. Perubahan iklim di bumi akhir-akhir ini juga mendukung persebaran hujan yang tidak merata sehingga menimbulkan berbagai masalah di bumi. Untuk itu kita sudah semestinya membantu menormalkan iklim yang berubah akibat ulah manusia agar anak cucu kita kelak tidak menderita dan terbunuh akibat kesalahan yang kita lakukan saat ini.
Diposting oleh
my family
02.36
Gerhana matahari
Dari Wikipedia Bahasa Melayu, ensiklopedia bebas.
Geometri Gerhana Matahari penuh (tidak menurut skala)
Gambar gerhana matahari penuh 11 Ogos 1999
Gerhana matahari berlaku apabila kedudukan bulan terletak di antara bumi dan matahari oleh itu menutup cahaya matahari samada separa atau sepenuhnya. Walaupun bulan lebih kecil, bayangan bulan mampu melindungi cahaya matahari sepenuhnya kerana bulan dengan purata jarak 384,400 kilometer adalah lebih dekat kepada bumi berbanding matahari yang mempunyai jarak purata 149,680,000 kilometer.
Gerhana matahari boleh dibahagi kepada 3 iaitu gerhana penuh, gerhana separuh, dan gerhana analus. Gerhana penuh apabila matahari ditutup sepenuhnya oleh bulan disebabkan bulan berada dekat ke bumi dalam orbit bujurnya, gerhana separuh apabila bulan hanya menutup sebahagian daripada matahari, dan gerhana analus yang terjadi apabila bulan hanya menutup sebahagian daripada matahari dan cahaya matahari selebihnya membentuk cincin bercahaya sekeliling bayangan bulan yang dikenali sebagai 'corona'.
Gerhana matahari berlaku selama 7 minit 30 saat pada tempat yang paling lama. Ketika gerhana matahari, orang ramai dilarang melihat ke arah matahari secara langsung kerana ini boleh merosakkan mata dan mengakibatkan buta.
Bagi mereka yang beragama Islam, mereka digalakkan untuk melakukan Solat Sunat Gerhana ketika berlakunya gerhana.
Pada 26 Januari 2009 berlaku lagi kekuasaan Allah pada alam ini iaitu fenomena Gerhana Matahari. Waktu berlaku pada waktu 16:20 waktu Malaysia dan berakhir dijangka 19:00. Adalah sebaik-baiknya memulakan solat gerhana matahari berjemaah di surau atau masjid di tempat anda kerana dapat mendengar khutbah yang bakal dibacakan oleh khatib. Hukum khutbah dan solat gerhana adalah sunat muakad(yang dituntut) , jadi meninggalkannya hukumnya makruh(dibenci) tanpa uzur syari'e.
There are four types of solar eclipses:
- A total eclipse occurs when the Sun is completely obscured by the Moon. The intensely bright disk of the Sun is replaced by the dark silhouette of the Moon, and the much fainter corona is visible. During any one eclipse, totality is visible only from at most a narrow track on the surface of the Earth.
- An annular eclipse occurs when the Sun and Moon are exactly in line, but the apparent size of the Moon is smaller than that of the Sun. Hence the Sun appears as a very bright ring, or annulus, surrounding the outline of the Moon.
- A hybrid eclipse (also called annular/total eclipse) transitions between a total and annular eclipse. At some points on the surface of the Earth it is visible as a total eclipse, whereas at others it is annular. Hybrid eclipses are comparatively rare.
- A partial eclipse occurs when the Sun and Moon are not exactly in line and the Moon only partially obscures the Sun. This phenomenon can usually be seen from a large part of the Earth outside of the track of an annular or total eclipse. However, some eclipses can only be seen as a partial eclipse, because the umbra never intersects the Earth's surface, passing above the Earth's polar regions.
The Sun's distance from the Earth is about 390 times the Moon's distance, and the Sun's diameter is about 400 times the Moon's diameter. Because these ratios are approximately the same, the Sun and the Moon as seen from Earth appear to be approximately the same size: about 0.5 degree of arc in angular measure.
The Moon transiting in front of the Sun as seen from
STEREO-B on February 25, 2007 at 4.4 times the distance between the Earth and the Moon.
[1] The Moon's orbit around the Earth is an ellipse, as is the Earth's orbit around the Sun; the apparent sizes of the Sun and Moon therefore vary.[2][3] The magnitude of an eclipse is the ratio of the apparent size of the Moon to the apparent size of the Sun during an eclipse. An eclipse when the Moon is near its closest distance from the Earth (i.e., near its perigee) can be a total eclipse because the Moon will appear to be large enough to cover completely the Sun's bright disk, or photosphere; a total eclipse has a magnitude greater than 1. Conversely, an eclipse when the Moon is near its farthest distance from the Earth (i.e., near its apogee) can only be an annular eclipse because the Moon will appear to be slightly smaller than the Sun; the magnitude of an annular eclipse is less than 1. Slightly more solar eclipses are annular than total because, on average, the Moon lies too far from Earth to cover the Sun completely. A hybrid eclipse occurs when the magnitude of an eclipse transitions during the event from smaller than one to larger than one—or vice versa—so the eclipse appears to be total at some locations on Earth and annular at other locations.[4]
The Earth's orbit around the Sun is also elliptical, so the Earth's distance from the Sun varies throughout the year. This also affects the apparent sizes of the Sun and Moon, but not so much as the Moon's varying distance from the Earth. When the Earth approaches its farthest distance from the Sun (the aphelion) in July, this tends to favor a total eclipse. As the Earth approaches its closest distance from the Sun (the perihelion) in January, this tends to favor an annular eclipse.
[sunting] Istilah bagi gerhana pusat
Gerhana Pusat "Central eclipse" swering kali digunakan sebagai istilah umum bagi gerhana penuh, gerhana anular, atau gerhana kacukan. Ini bagaimanapun, tidak tepat: istilah bagi gerhana pusat merupakan di mana garis tengah umbra menyentuh permukaan bumi. Ia adalah mungkin, sungguhpun amat jarang, sebahagian umbra melintasi Bumi (dengan itu menghasilkan gerhana anular atau gerhana penuh), tetapi tidak garis tengahnya. Ini sering kali dikenali sebagai gerhana penuh tidak tengah atau gerhana anular.[5] The next non-central solar eclipse will be on April 29, 2014. This will be an annular eclipse. The next non-central total solar eclipse will be on April 9, 2043.[6]
Fasa yang dilihat semasa gerhana penuh dikenali sebagai:
- First Contact — when the moon's shadow first becomes visible on the solar disk. Some also name individual phases between First and Second Contact e.g. Pac-Man phase.
- Second Contact — starting with Baily's Beads {caused by light shining through valleys on the moon's surface} and the Diamond Ring. Almost the entire disk is covered.
- Totality — with the shadow of the moon obscuring the entire disk of the sun and only the corona visible
- Third Contact — when the first bright light becomes visible and the shadow is moving away from the sun. Again a Diamond Ring may be observed
Diposting oleh
my family
02.25
Gerhana matahari
Dari Wikipedia Bahasa Melayu, ensiklopedia bebas.
Geometri Gerhana Matahari penuh (tidak menurut skala)
Gambar gerhana matahari penuh 11 Ogos 1999
Gerhana matahari berlaku apabila kedudukan bulan terletak di antara bumi dan matahari oleh itu menutup cahaya matahari samada separa atau sepenuhnya. Walaupun bulan lebih kecil, bayangan bulan mampu melindungi cahaya matahari sepenuhnya kerana bulan dengan purata jarak 384,400 kilometer adalah lebih dekat kepada bumi berbanding matahari yang mempunyai jarak purata 149,680,000 kilometer.
Gerhana matahari boleh dibahagi kepada 3 iaitu gerhana penuh, gerhana separuh, dan gerhana analus. Gerhana penuh apabila matahari ditutup sepenuhnya oleh bulan disebabkan bulan berada dekat ke bumi dalam orbit bujurnya, gerhana separuh apabila bulan hanya menutup sebahagian daripada matahari, dan gerhana analus yang terjadi apabila bulan hanya menutup sebahagian daripada matahari dan cahaya matahari selebihnya membentuk cincin bercahaya sekeliling bayangan bulan yang dikenali sebagai 'corona'.
Gerhana matahari berlaku selama 7 minit 30 saat pada tempat yang paling lama. Ketika gerhana matahari, orang ramai dilarang melihat ke arah matahari secara langsung kerana ini boleh merosakkan mata dan mengakibatkan buta.
Bagi mereka yang beragama Islam, mereka digalakkan untuk melakukan Solat Sunat Gerhana ketika berlakunya gerhana.
Pada 26 Januari 2009 berlaku lagi kekuasaan Allah pada alam ini iaitu fenomena Gerhana Matahari. Waktu berlaku pada waktu 16:20 waktu Malaysia dan berakhir dijangka 19:00. Adalah sebaik-baiknya memulakan solat gerhana matahari berjemaah di surau atau masjid di tempat anda kerana dapat mendengar khutbah yang bakal dibacakan oleh khatib. Hukum khutbah dan solat gerhana adalah sunat muakad(yang dituntut) , jadi meninggalkannya hukumnya makruh(dibenci) tanpa uzur syari'e.
There are four types of solar eclipses:
- A total eclipse occurs when the Sun is completely obscured by the Moon. The intensely bright disk of the Sun is replaced by the dark silhouette of the Moon, and the much fainter corona is visible. During any one eclipse, totality is visible only from at most a narrow track on the surface of the Earth.
- An annular eclipse occurs when the Sun and Moon are exactly in line, but the apparent size of the Moon is smaller than that of the Sun. Hence the Sun appears as a very bright ring, or annulus, surrounding the outline of the Moon.
- A hybrid eclipse (also called annular/total eclipse) transitions between a total and annular eclipse. At some points on the surface of the Earth it is visible as a total eclipse, whereas at others it is annular. Hybrid eclipses are comparatively rare.
- A partial eclipse occurs when the Sun and Moon are not exactly in line and the Moon only partially obscures the Sun. This phenomenon can usually be seen from a large part of the Earth outside of the track of an annular or total eclipse. However, some eclipses can only be seen as a partial eclipse, because the umbra never intersects the Earth's surface, passing above the Earth's polar regions.
The Sun's distance from the Earth is about 390 times the Moon's distance, and the Sun's diameter is about 400 times the Moon's diameter. Because these ratios are approximately the same, the Sun and the Moon as seen from Earth appear to be approximately the same size: about 0.5 degree of arc in angular measure.
The Moon transiting in front of the Sun as seen from
STEREO-B on February 25, 2007 at 4.4 times the distance between the Earth and the Moon.
[1] The Moon's orbit around the Earth is an ellipse, as is the Earth's orbit around the Sun; the apparent sizes of the Sun and Moon therefore vary.[2][3] The magnitude of an eclipse is the ratio of the apparent size of the Moon to the apparent size of the Sun during an eclipse. An eclipse when the Moon is near its closest distance from the Earth (i.e., near its perigee) can be a total eclipse because the Moon will appear to be large enough to cover completely the Sun's bright disk, or photosphere; a total eclipse has a magnitude greater than 1. Conversely, an eclipse when the Moon is near its farthest distance from the Earth (i.e., near its apogee) can only be an annular eclipse because the Moon will appear to be slightly smaller than the Sun; the magnitude of an annular eclipse is less than 1. Slightly more solar eclipses are annular than total because, on average, the Moon lies too far from Earth to cover the Sun completely. A hybrid eclipse occurs when the magnitude of an eclipse transitions during the event from smaller than one to larger than one—or vice versa—so the eclipse appears to be total at some locations on Earth and annular at other locations.[4]
The Earth's orbit around the Sun is also elliptical, so the Earth's distance from the Sun varies throughout the year. This also affects the apparent sizes of the Sun and Moon, but not so much as the Moon's varying distance from the Earth. When the Earth approaches its farthest distance from the Sun (the aphelion) in July, this tends to favor a total eclipse. As the Earth approaches its closest distance from the Sun (the perihelion) in January, this tends to favor an annular eclipse.
[sunting] Istilah bagi gerhana pusat
Gerhana Pusat "Central eclipse" swering kali digunakan sebagai istilah umum bagi gerhana penuh, gerhana anular, atau gerhana kacukan. Ini bagaimanapun, tidak tepat: istilah bagi gerhana pusat merupakan di mana garis tengah umbra menyentuh permukaan bumi. Ia adalah mungkin, sungguhpun amat jarang, sebahagian umbra melintasi Bumi (dengan itu menghasilkan gerhana anular atau gerhana penuh), tetapi tidak garis tengahnya. Ini sering kali dikenali sebagai gerhana penuh tidak tengah atau gerhana anular.[5] The next non-central solar eclipse will be on April 29, 2014. This will be an annular eclipse. The next non-central total solar eclipse will be on April 9, 2043.[6]
Fasa yang dilihat semasa gerhana penuh dikenali sebagai:
- First Contact — when the moon's shadow first becomes visible on the solar disk. Some also name individual phases between First and Second Contact e.g. Pac-Man phase.
- Second Contact — starting with Baily's Beads {caused by light shining through valleys on the moon's surface} and the Diamond Ring. Almost the entire disk is covered.
- Totality — with the shadow of the moon obscuring the entire disk of the sun and only the corona visible
- Third Contact — when the first bright light becomes visible and the shadow is moving away from the sun. Again a Diamond Ring may be observed
Diposting oleh
my family
02.25
Gerhana matahari
Dari Wikipedia Bahasa Melayu, ensiklopedia bebas.
Geometri Gerhana Matahari penuh (tidak menurut skala)
Gambar gerhana matahari penuh 11 Ogos 1999
Gerhana matahari berlaku apabila kedudukan bulan terletak di antara bumi dan matahari oleh itu menutup cahaya matahari samada separa atau sepenuhnya. Walaupun bulan lebih kecil, bayangan bulan mampu melindungi cahaya matahari sepenuhnya kerana bulan dengan purata jarak 384,400 kilometer adalah lebih dekat kepada bumi berbanding matahari yang mempunyai jarak purata 149,680,000 kilometer.
Gerhana matahari boleh dibahagi kepada 3 iaitu gerhana penuh, gerhana separuh, dan gerhana analus. Gerhana penuh apabila matahari ditutup sepenuhnya oleh bulan disebabkan bulan berada dekat ke bumi dalam orbit bujurnya, gerhana separuh apabila bulan hanya menutup sebahagian daripada matahari, dan gerhana analus yang terjadi apabila bulan hanya menutup sebahagian daripada matahari dan cahaya matahari selebihnya membentuk cincin bercahaya sekeliling bayangan bulan yang dikenali sebagai 'corona'.
Gerhana matahari berlaku selama 7 minit 30 saat pada tempat yang paling lama. Ketika gerhana matahari, orang ramai dilarang melihat ke arah matahari secara langsung kerana ini boleh merosakkan mata dan mengakibatkan buta.
Bagi mereka yang beragama Islam, mereka digalakkan untuk melakukan Solat Sunat Gerhana ketika berlakunya gerhana.
Pada 26 Januari 2009 berlaku lagi kekuasaan Allah pada alam ini iaitu fenomena Gerhana Matahari. Waktu berlaku pada waktu 16:20 waktu Malaysia dan berakhir dijangka 19:00. Adalah sebaik-baiknya memulakan solat gerhana matahari berjemaah di surau atau masjid di tempat anda kerana dapat mendengar khutbah yang bakal dibacakan oleh khatib. Hukum khutbah dan solat gerhana adalah sunat muakad(yang dituntut) , jadi meninggalkannya hukumnya makruh(dibenci) tanpa uzur syari'e.
There are four types of solar eclipses:
- A total eclipse occurs when the Sun is completely obscured by the Moon. The intensely bright disk of the Sun is replaced by the dark silhouette of the Moon, and the much fainter corona is visible. During any one eclipse, totality is visible only from at most a narrow track on the surface of the Earth.
- An annular eclipse occurs when the Sun and Moon are exactly in line, but the apparent size of the Moon is smaller than that of the Sun. Hence the Sun appears as a very bright ring, or annulus, surrounding the outline of the Moon.
- A hybrid eclipse (also called annular/total eclipse) transitions between a total and annular eclipse. At some points on the surface of the Earth it is visible as a total eclipse, whereas at others it is annular. Hybrid eclipses are comparatively rare.
- A partial eclipse occurs when the Sun and Moon are not exactly in line and the Moon only partially obscures the Sun. This phenomenon can usually be seen from a large part of the Earth outside of the track of an annular or total eclipse. However, some eclipses can only be seen as a partial eclipse, because the umbra never intersects the Earth's surface, passing above the Earth's polar regions.
The Sun's distance from the Earth is about 390 times the Moon's distance, and the Sun's diameter is about 400 times the Moon's diameter. Because these ratios are approximately the same, the Sun and the Moon as seen from Earth appear to be approximately the same size: about 0.5 degree of arc in angular measure.
The Moon transiting in front of the Sun as seen from
STEREO-B on February 25, 2007 at 4.4 times the distance between the Earth and the Moon.
[1] The Moon's orbit around the Earth is an ellipse, as is the Earth's orbit around the Sun; the apparent sizes of the Sun and Moon therefore vary.[2][3] The magnitude of an eclipse is the ratio of the apparent size of the Moon to the apparent size of the Sun during an eclipse. An eclipse when the Moon is near its closest distance from the Earth (i.e., near its perigee) can be a total eclipse because the Moon will appear to be large enough to cover completely the Sun's bright disk, or photosphere; a total eclipse has a magnitude greater than 1. Conversely, an eclipse when the Moon is near its farthest distance from the Earth (i.e., near its apogee) can only be an annular eclipse because the Moon will appear to be slightly smaller than the Sun; the magnitude of an annular eclipse is less than 1. Slightly more solar eclipses are annular than total because, on average, the Moon lies too far from Earth to cover the Sun completely. A hybrid eclipse occurs when the magnitude of an eclipse transitions during the event from smaller than one to larger than one—or vice versa—so the eclipse appears to be total at some locations on Earth and annular at other locations.[4]
The Earth's orbit around the Sun is also elliptical, so the Earth's distance from the Sun varies throughout the year. This also affects the apparent sizes of the Sun and Moon, but not so much as the Moon's varying distance from the Earth. When the Earth approaches its farthest distance from the Sun (the aphelion) in July, this tends to favor a total eclipse. As the Earth approaches its closest distance from the Sun (the perihelion) in January, this tends to favor an annular eclipse.
[sunting] Istilah bagi gerhana pusat
Gerhana Pusat "Central eclipse" swering kali digunakan sebagai istilah umum bagi gerhana penuh, gerhana anular, atau gerhana kacukan. Ini bagaimanapun, tidak tepat: istilah bagi gerhana pusat merupakan di mana garis tengah umbra menyentuh permukaan bumi. Ia adalah mungkin, sungguhpun amat jarang, sebahagian umbra melintasi Bumi (dengan itu menghasilkan gerhana anular atau gerhana penuh), tetapi tidak garis tengahnya. Ini sering kali dikenali sebagai gerhana penuh tidak tengah atau gerhana anular.[5] The next non-central solar eclipse will be on April 29, 2014. This will be an annular eclipse. The next non-central total solar eclipse will be on April 9, 2043.[6]
Fasa yang dilihat semasa gerhana penuh dikenali sebagai:
- First Contact — when the moon's shadow first becomes visible on the solar disk. Some also name individual phases between First and Second Contact e.g. Pac-Man phase.
- Second Contact — starting with Baily's Beads {caused by light shining through valleys on the moon's surface} and the Diamond Ring. Almost the entire disk is covered.
- Totality — with the shadow of the moon obscuring the entire disk of the sun and only the corona visible
- Third Contact — when the first bright light becomes visible and the shadow is moving away from the sun. Again a Diamond Ring may be observed
aku suka belajar blogger...........................................................!
