Rabu, 14 Januari 2009

[FISIKA] Digest Number 2642

Milis Fisika Indonesia (MFI)

Messages In This Digest (6 Messages)

Messages

1.

Fwd: [pendidikan] OOT: Lowongan

Posted by: "A. Muzi Marpaung" kakmuzi@gmail.com

Mon Jan 12, 2009 7:59 pm (PST)

---------- Pesan terusan ----------
Dari: A. Muzi Marpaung <bang_muzi@yahoo.com.au>
Tanggal: 12 Januari 2009 15:01
Subjek: [pendidikan] OOT: Lowongan
Ke: muzi@cakrawala-ilma.com

Mohon maaf pak Moderator, nitip lowongan pekerjaan

Tantangan Bagi Jiwa Muda

Hingga hari ini, ribuan anak bermain dan bersenang-senang
dengan sains di banyak sekolah. Menjadi bibit yang tumbuh subur untuk kelak
menjadi generasi Indonesia yang kreatif, inovatif dan inventif. Tapi, masih
ada
jutaan anak yang belum menikmati serunya sains. Cakrawala ilma, sebagai
perusahaan yang bergerak di bidang pembelajaran sains yang menyenangkan
dengan
jangkauan terluas di Indonesia, bertekad untuk merangkul semua anak
Indonesia
dalam sebuah rumah sains yang hangat, inspiratif dan menyenangkan. Untuk
mewujudkan tekad besar itu kami mencari sosok pribadi yang menyukai
tantangan,
imajinatif, menyenangi dunia anak, ceria dan tangguh.

1. Fasilitator Sains (Fisika, Kimia, Biologi – 5 orang)
Untuk posisi ini Anda harus berusia
di bawah 28 tahun, sarjana MIPA atau jurusan IPA lainnya, mempunyai
kapasitas
yang besar untuk menyerap pengetahuan yang luas dan berkemampuan nalar yang
kuat, serta pembelajar yang cepat dan akurat. Anda bertugas memfasilitasi
anak-anak bermain sains, menyediakan alat dan bahan eksperimen, menemukan
eksperimen-eksperimen baru dan memodifikasi eksperimen-eksperimen lama.
Seringkali Anda harus bekerja dengan inisiatif sendiri, dan dengan tenggat
yang
ketat.

1. Sales and Marketing Executive (2 orang)
Untuk posisi ini Anda harus berusia
di bawah 30 tahun, sarjana dari semua jurusan, mempunyai semangat besar
untuk
mencapai target yang tinggi, dapat dipercaya dan bertanggung jawab, serta
mempunyai mobilitas yang tinggi. Tugas Anda adalah seperti anak panah yang
melesat menancapkan manfaat ilma ke segala penjuru, membangun kerjasama
mutualistis dengan sekolah, perusahaan swasta, lembaga, organisasi
masyarakat
dan konsumen umum. Anda haruslah perencana yang efektif dan efisien,
sekaligus
eksekutor yang cekatan dan luwes. Kecerdasan untuk berpikir lateral
merupakan
nilai tambah yang amat dipertimbangkan

Kirimkan segera CV Anda melalui
e-mail ke eva.nurnisya@yahoo.com.sg <eva.nurnisya%40yahoo.com.sg>
2a.

Re: Butuh info tentang kegiatan SCADA dan DCS di Indonesia

Posted by: "Haryo Sumowidagdo" haryo@fnal.gov   haryo_fnal

Mon Jan 12, 2009 11:45 pm (PST)


Halo mas Hosana,

Wah, terimakasih banyak nih untuk penjelasan dan diskusinya yang detail.
Terimakasih pula untuk mas Rudy, de Guzman, dan Kemal.
Balasan ini akan saya cc juga ke fisika Indonesia

> Kalau boleh tahu, bapak mengembangkan software kontrol untuk fisika
> partikel yang bagaimana ya dalam hubungannya dengan SCADA ??

Ok, saya perlu menerangkan sedikit tentang detektor fisika partikel.
Detektor partikel pada dasarnya merupakan kumpulan banyak sekali sensor.
Jumlah readout channelnya banyak sekali: CMS (detektor saya sekarang)
memiliki l.k. 100 juta readout channel. Ada banyak tipe detektor yang
dipakai di detektor fisika partikel (kalau pernah ikut/belajar tentang
instrumentasi untuk reaktor nuklir atau proteksi radiasi, fisika
partikel menggunakan tipe-tipe detektor yang sama).

Sensor-sensor ini begitu banyak channelnya dan memberikan informasi
begitu banyak (detektor saya bisa memberikan 100 MB - 1 GB per detik),
sehingga terkadang produk komersial semacam PLC tidak bisa langsung
dipakai. Jadi fisikawan partikel eksperimen merancang custom-design
electronic board khusus untuk memungkinkan membaca sensor-sensor
tersebut. Electronic board ini diproduksi massa oleh perusahaan
elektronik komersial (bisa ada ribuan untuk 1 tipe sensor saja). Dalam
bidang ini electronic board semacam itu disebut 'readout electronics'.
Biasanya tiap board punya ADC sendiri (parallel bbrp channel sekaligus),
preamp, readout buffer, clock, etc. Terkadang bahkan untuk bbrp tipe
sensor, readout electronics ini dibuat dalam bentuk ASIC. Dari readout
electronics barulah data digabung dan ditransmisi ke computer farm untuk
kemudian disimpan dalam disk.

'Readout electronics' tentu tidak bisa jalan sendiri. Mereka harus
dikumpulkan dan ditaruh di rak-rak (crate), harus mendapat catu daya,
dan harus berada dalam ruangan yang temperatur dan kelembabannya
dimonitor.

Dalam pengoperasiannya, kita biasanya membedakan 2 tipe data yang
dimonitor:

a) physics data: data yang berkaitan dengan posisi, waktu, energi, dan
momentum partikel. Data inilah yang dibaca oleh 'readout electronics'.
Ini lebih merupakan spesialisasi fisika partikel eksperimen.

b) monitoring/environmental data: data yang berkaitan dengan kondisi
operasional sensor-sensor dan 'readout electronics' tsb. Untuk tipe
data kedua inilah dimana ada perlunya SCADA/DCS !

Sistem sensor-sensor ini begitu besar dan kompleks sehingga kita ingin
tahu misalnya:

1) sensor-sensor pada umumnya terletak didalam ruangan bawah tanah, dan
terisolasi dari akses operator selama akselerator dijalankan. Jadi kita
harus bisa mengontrol kondisi sensor-sensor selama akselerator
dijalankan.

2) tingkat radiasi dalam ruangan bawah tanah dimana eksperimen
dijalankan.

3) apakah sensor-sensor semuanya mendapat catu daya yang cukup ?
(Monitoring arus, tegangan, daya, dll)

4) apakah readout electronics juga mendapat catu daya yang cukup.

5) apakah sensor-sensor sudah diset untuk beroperasi pada mode yang
diinginkan (cek bit setting tiap-tiap sensor)

6) situasi operasional lain-lain seperti: tekanan gas dalam ionization
chamber (Geiger counter), kemurnian/purity dari liquid helium atau
liquid argon, kelembaban udara, tekanan atmosfer, bahkan hingga
pasang-naik turun Danau Geneva atau apakah ada kereta api lewat di
Stasiun Geneva (Tahun 1990-an, detektor di CERN begitu sensitif sehingga
data-data dari detektor menunjukkan efek dari pasang naik-turun dan
kereta api lewat - no kidding !).

Fisikawan partikel ingin mengetahui kondisi operasional detektor, karena
kita ingin 'physics data'-nya direkam saat kondisi detektor
prima/optimal. Jangan sampai tahu-tahu mengklaim sudah menemukan Higgs
boson, tapi ternyata ketika dicek, ketika data direkam salah satu power
supply jebol. Jadi memang ada kesamaan aspek antara pengoperasian
sebuah detektor partikel dengan pengoperasian instalasi migas, pabrik
kimia, atau building automation ! Kita ingin produk yang kelas utama,
jadi kita ingin detektor kita beroperasi sempurna, tanpa cacat.

Selain untuk detektor, tentunya sistem akselerator semacam CERN LHC juga
memerlukan SCADA. Akselerator partikel terdiri dari sekumpulan
magnet-magnet superkonduktor dengan cryostat helium dan segala macam
sistem transmisi arus listrik tegangan tinggi. Disini kita perlu
mengatur/memonitor misalnya:

- besar dan arah medan magnet
- kondisi operasional cryostat -- jangan sampai temperaturnya naik
diatas temperatur kritis Tc dan superkonduktor kehilangan sifat
superkonduktivitasnya
- kondisi vakum dalam pipa akselerator
- besar arus dari particle beam dalam akselerator

Jadi berbeda dengan detektor partikel. Namun prinsipnya sama.

Ada 2 set slide yang menjelaskan dengan bagus sekali relasi antara
SCADA/DCS dengan experimental high energy physics:

http://itcobe.web.cern.ch/itcobe/Services/Pvss/ScadaLab/CSC/2001/lecture1.pdf
http://itcobe.web.cern.ch/itcobe/Services/Pvss/ScadaLab/CSC/2001/lecture2.pdf

CERN sendiri sekarang mengadopsi software SCADA komersial dari
perusahaan Austria (ETM) bernama PVSS.
http://cerncourier.com/cws/article/cern/29358

Opini saya sih, jika di Indonesia SCADA/DCS kegiatannya sudah aktif dan
berjalan, ada peluang untuk membuka jalur dan menerapkannya ke fisika
partikel eksperimen. Yang beda cuma target customernya: yang ada
sekarang customernya adalah industri, sekarang ditambah customer baru
yakni eksperimen fisika partikel eksperimen. Cuma membangun
koneksi/kerja-samanya susah. Saya belum jadi apa-apa baik di Indonesia
maupun disini ! Makanya kalau akhir-akhir ini saya sering berkampanya
agar orang masuk fisika partikel eksperimen, ya ini salah satu
tujuannya. Semakin banyak orang Indonesia kerja di bidang ini, semakin
ada kemungkinan membuka koneksi dan kerja sama.

---
Haryo Sumowidagdo
Department of Physics and Astronomy
University of Califonia, Riverside

E-mail : haryo@fnal.gov CMS Experiment at CERN LHC
Web : http://home.fnal.gov/~haryo LHC Physics Center
Phone : +1 +630 840 8567 Fermilab MS 121
Fax : +1 +630 840 6736 Batavia, IL 60510, USA

# ``Jer basuki mawa beya'' -- (Javanese proverb) --

3a.

Re: APA YANG TERJADI ketika hujan turun ?

Posted by: "Eka Subyantara" eka.subyantara@widyatama.ac.id   eka_subyantara

Tue Jan 13, 2009 2:32 am (PST)

Dengan tidak bermaksud mementahkan apa yang sudah dibicarakan, saya coba
sampaikan kembali penjelasan yang pernah saya terima dari guru tentang
mengapa kita merasa gerah sebelum hujan turun.

Pada saat menjelang hujan kelembaban udara mencapai maksimum, sehingga
keringat kita tidak bisa lagi menguap untuk membawa sebagian panas tubuh
kita (padahal tubuh selalu memproduksi panas). Akibatnya adalah kita
'terbakar' panas tubuh sendiri yang kita sebut dengan kegerahan.

Ketika hujan telah turun maka kelembaban udara pun menurun karena uap air
sebagian besar sudah menjadi tetes hujan. Keadaan ini memungkinkan keringat
kita bisa menguap kembali untuk mendinginkan tubuh kita. Itulah kenapa
setelah hujan turun kita akan merasa dingin kembali.

Ada juga yang menjelaskan, bahwa pada saat hujan turun terjadi banjir ion
negatif di udara, sehingga kita merasa segar. Untuk hal ini saya butuh
konfirmasi dan pencerahan dari hadirin yang tahu persisnya.

Ayo kita berbagi tahu ... :)

- eka -

2009/1/12 erika nurhansyah <er_erhanz@yahoo.com>

> klw mnurut ilmu pengawuranqyu sih gini....
> udara yang panas(suhu tinggi) masa jenisnya kecil akan bergerak naik karena
> lebih ringan dr udara yg lbih dingin.
>
> pas sampai di atas, udara kan reuni berkumpul bareng tmen2nya, lha
> terjadilah persekutuan(penggumpalan/kondensasi) awan.
>
> karena tlah menjadi mendung dan memadat lagi jadi air,,,,ada lapisan air
> yang partikelnya padat.
>
> Trus udara panas dari Bumi tercinta masih truz naik, eH Mentok di
> lapisan Mendung basah tadi, jadi udara panas terkungkung.
> .......makanya kita merasa sumuk, ongkep atau bahasa kerennya kegerahan.
> HAAHAHAHAHA.
>
> ..........................Don't Try This at
> Home..............................
>
>
4a.

Cari Buku Elektronika & Bahan Skripsi. Mohon Bantuan ^_^

Posted by: "Gita Rustiawati Gita" anfa_hanan16@yahoo.com   anfa_hanan16

Tue Jan 13, 2009 8:27 am (PST)

I. CARI BUKU ELEKTRONIKA ;

1. Basic
Electronics. Bernard GROB - Mitchel E.
SCHULTZ
2. Basic
Electronics for Scientists. James J. BROPHY
3. Digital
Principles and Application by Albert Paul Malvino and Donald P. Leach
4. Semiconductor Circuit Approximations: An
Introduction to Transistors and Integrated Circuits by Albert Paul Malvino

Buku bisa berupa
softbook (e-book) atau alamat download atau alamat took, yang bisa di
dapat di daerah terdekat (wilayah Jakarta).
Date line
sebelum tanggal 16 Januari 2009, hari jum̢۪at. Kalau bisa (di usahakan). ^_^
Trima kasih atas
segala bantuannya.

II. CARI BAHAN TUK
SKRIPSI ;
Temen2 ada yang punya referensi
buku tentang Concept
Attainment(Pemahaman
Konsep) Dalam Pembelajaran?
Klo bisa yang mengarah ke sains atau fisika.
Dah nyari di internet, tapi rata-rata bentuknya jurnal internasional
Klo ada, tlg reply ke e-Mail; anfa_hanan16@yahoo.com
Tengkyu

REPLY KE EMAIL fisika_indonesia@yahoogroups.com ATAU KE anfa_hanan16@yahoo.com . TENGKYU ^_^

4b.

Re: Cari Buku Elektronika & Bahan Skripsi. Mohon Bantuan ^_^

Posted by: "eva sakti" e_sakti@yahoo.com   e_sakti

Tue Jan 13, 2009 9:52 am (PST)

Hi Gita,

Saya pikir anda bisa dapatkan beberapa buku ini di perpustakaan
Dept. Phyisics UI di Kampus Depok.

Parada

--- On Tue, 1/13/09, Gita Rustiawati Gita <anfa_hanan16@yahoo.com> wrote:

From: Gita Rustiawati Gita <anfa_hanan16@yahoo.com>
Subject: [FISIKA] Cari Buku Elektronika & Bahan Skripsi. Mohon Bantuan ^_^
To: fisika_indonesia@yahoogroups.com
Date: Tuesday, January 13, 2009, 9:15 PM

I. CARI BUKU ELEKTRONIKA ;

1. Basic

Electronics. Bernard GROB - Mitchel E.

SCHULTZ

2. Basic

Electronics for Scientists. James J. BROPHY

3. Digital

Principles and Application by Albert Paul Malvino and Donald P. Leach

4. Semiconductor Circuit Approximations: An

Introduction to Transistors and Integrated Circuits by Albert Paul Malvino

Buku bisa berupa

softbook (e-book) atau alamat download atau alamat took, yang bisa di

dapat di daerah terdekat (wilayah Jakarta).

Date line

sebelum tanggal 16 Januari 2009, hari jum¢at. Kalau bisa (di usahakan). ^_^

Trima kasih atas

segala bantuannya.

II. CARI BAHAN TUK

SKRIPSI ;

Temen2 ada yang punya referensi

buku tentang Concept

Attainment(Pemahama n

Konsep) Dalam Pembelajaran?

Klo bisa yang mengarah ke sains atau fisika.

Dah nyari di internet, tapi rata-rata bentuknya jurnal internasional

Klo ada, tlg reply ke e-Mail; anfa_hanan16@ yahoo.com

Tengkyu

REPLY KE EMAIL fisika_indonesia@ yahoogroups. com ATAU KE anfa_hanan16@ yahoo.com . TENGKYU ^_^











5.

"Watch Out in 2011-12", Solar Forecast

Posted by: "miko" miekopyok@gmail.com

Tue Jan 13, 2009 8:28 am (PST)


The peak of the next sunspot cycle is expected in late 2011 or mid-2012 —
potentially affecting airline flights, communications satellites and
electrical
transmissions. But forecasters can't agree on how intense it will be.

The government's Space Environment Center in Boulder, Colo., tracks space
weather and forecasts its changes, which can affect millions of dollars
worth
of activities such as oil drilling, car navigation systems and astronauts.

Daniel Baker, director of the Laboratory for Atmospheric and Space Physics
at the University of Colorado-Boulder, noted that more than $200 billion of
satellites in space can be affected by changes in solar radiation as the
cycle
rises and falls.

Half of the specialists predicted a moderately strong cycle of 140 sunspots
expected to peak in October of 2011, while the rest called for a moderately
weak cycle of 90 sunspots peaking in August of 2012.

http://dsc. discovery.
com/news/2007/04/26/solarstorms_spa.html?category=space&guid=20070424164530

| Prof. The Houw Liong:
| " Betul, 2012 diperkirakan akan terjadi aktivitas matahari maksimum yang
| mungkin mengganggu sistem pelistrikan, sistem komunikasi dan sistem
| navigasi terutama bagian utara dan selatan Bumi, namun Indonesia juga
| akan kena dampaknya, selain itu di Indonesia peristiwa itu akan
| mempengaruhi cuaca, dan diperkirakan Jakarta dan berbagai tempat lain
| akan terjadi curah hujan maksimum.
| Lihat juga :
| http://sansteknologi.blogspot.com/ "

Sunspot cycle 24 begins at last

Welcome to the next 11 years...

Sunspot cycle 24 has begun with a whimper. The sun's face has been blank
for two months, leaving solar astronomers wondering whether the sun would
ever get active again.

Then, on Sunday, a new spot emerged. The active region had two dark cores,
each bigger than Earth.

"Everybody was excited. We have been looking forward to it - it's rather
like
a new birth," Eric Priest of the University of St Andrews in the UK told
New
Scientist. Unfortunately, while sunspots tend to last a couple of weeks on
average, these spots disappeared again after less than 48 hours.

Nevertheless, astronomers are still excited. In a new sunspot cycle, spots
appear at high latitudes and move towards the equator. They also have a
reversed polarity, their magnetic fields pointing in the opposite
direction to
the spots of the previous cycle. The recent spot 1002 had all the right
characteristics, so we are now officially on the next 11-year cycle.

http://www. newscientist.
com/blogs/shortsharpscience/2008/09/sunspot-cycle-24-begins-at-las.html

Sun Shows Signs Of Life: Long-Awaited Solar Cycle 24 Starting To Take Off

ScienceDaily (Nov. 12, 2008) — After two-plus years of few sunspots, even
fewer solar flares, and a generally eerie calm, the sun is finally
showing signs
of life.

Even more significant is the fact that four of the five sunspot groups
belonged
to Solar Cycle 24, the long-awaited next installment of the sun's
11-year solar
cycle. "October was the first time we've seen sunspots from new Solar
Cycle 24
outnumbering spots from old Solar Cycle 23.

But it's a start. Stay tuned for solar activity.

http://www. sciencedaily. com/releases/2008/11/081111230341.htm

Solar Flare Surprise

Dec. 15, 2008: Solar flares are the most powerful explosions in the
solar system.
Packing a punch equal to a hundred million hydrogen bombs, they obliterate
everything in their immediate vicinity. Not a single atom should remain
intact.

http://science. nasa. gov/headlines/y2008/15dec_solarflaresurprise.htm

Apparently, Planet X (a.k.a. Nibiru) was spotted by astronomers in the
early 1980's in the outermost reaches of the Solar System. It has been
tracked by infrared observatories; seen lurking around in the Kuiper Belt
and now it is speeding right toward us and will enter the inner Solar
System in 2012.

So what does this mean to us? Well, the effects of the approach of Planet X
on our planet will be biblical, and what's more the effects are being felt
right now. Millions, even billions of people will die, global warming will
increase; earthquakes, drought, famine, wars, social collapse, even killer
solar flares will be caused by Nibiru blasting through the core of the
Solar
System.

As investigated in my previous article "No Doomsday in 2012", a lot of
weight
had been placed on the end of an ancient Mayan calendar, the "Long Count".
According to this calendar and Mayan myth, something is going to happen on
December 21st, 2012. Now the world's Planet X supporters seem to have
calculated that this hypothetical, deadly planet will arrive from a highly
eccentric orbit to wreak gravitational havoc on Earth, sparking geological,
social, economic and environmental damage, killing a high proportion of
life…
in 2012.

http://www. universetoday. com/2008/05/25/2012-no-planet-x/

>>>> Beberapa hari yang lalu Mama louren ditanya di sebuah TV swasta
>>>> tentang 2012, beliau menjawab dia tidak dapat menembus 2012 dan
>>>> setelahnya, dia hanya bilang akan ada NEW ORDE

Sunspot Is Harbinger Of New Solar Cycle, Increasing Risk For Electrical
Systems

A new 11-year cycle of heightened solar activity, bringing with it
increased
risks for power grids, critical military, civilian and airline
communications,
GPS signals and even cell phones and ATM transactions, showed signs it
was on its way late Thursday when the cycle's first sunspot appeared in
the sun's Northern Hemisphere, NOAA scientists said.

During a solar storm, highly charged material ejected from the sun may head
toward Earth, where it can bring down power grids, disrupt critical
communications,
and threaten astronauts with harmful radiation. Storms can also knock out
commercial communications satellites and swamp Global Positioning System
signals. Routine activities such as talking on a cell phone or getting
money from
an ATM machine could suddenly halt over a large part of the globe.

A sunspot is an area of highly organized magnetic activity on the
surface of
the sun. The new 11-year cycle, called Solar Cycle 24, is expected to build
gradually, with the number of sunspots and solar storms reaching a maximum
by 2011 or 2012, though devastating storms can occur at any time.

http://www. sciencedaily. com/releases/2008/01/080107143109.htm

Sun's Magnetic Field May Impact Weather And Climate:
Sun Cycle Can Predict Rainfall Fluctuations

ScienceDaily (Dec. 3, 2008) — The sun's magnetic field may have a
significant
impact on weather and climatic parameters in Australia and other
countries in
the northern and southern hemispheres. According to a study in Geographical
Research, the droughts are related to the solar magnetic phases and not the
greenhouse effect.

The study uses data from 1876 to the present to examine the correlation
between
solar cycles and the extreme rainfall in Australia.

It finds that the Southern Oscillation Index (SOI) – the basic tool for
forecasting
variations in global and oceanic patterns – and rainfall fluctuations
recorded over
the last decade are similar to those in 1914 -1924.

http://www. sciencedaily. com/releases/2008/12/081202081449.htm

Scientists Predict Big Sunspot Cycle Coming

Solar scientists said Monday the next sunspot cycle could be 30 percent
to 50
percent stronger than the last one, and it could begin up to a year
later than
expected – although other scientists dispute the timing prediction.

The peak of the cycle, called the Solar Maximum, generates more frequent
magnetic storms and ejections of energetic particles that can slow
satellite
orbits - thereby interfering with global navigation – as well as disrupt
communications and bring down power systems.

During a telephone briefing for reporters Monday, the scientists said
they have
great confidence in the forecast, because their model has matched the
historical
data from the past eight solar cycles with more than 98 percent accuracy.

Their Predictive Flux-transport Dynamo Model is enabling NCAR scientists to
predict that the next solar cycle, known as Cycle 24, will produce sunspots
across an area slightly larger than 2.5 percent of the visible surface
of the
Sun. They said they expect the cycle to begin in late 2007 or early 2008,
which is about six months to 12 months later than a cycle would normally
start.
Cycle 24 is expected to reach its peak sometime in 2012.

Both groups said the model should help them to forecast sunspot activity
for
two solar cycles, or 22 years, into the future. The NCAR team is
planning in
the next year to issue a forecast of Cycle 25, which will peak in the early
2020s.

http://www. spacedaily.
com/reports/Scientists_Predict_Big_Sunspot_Cycle_Coming.html

Scientists predict next solar cycle peak
Space weather forecasters can't agree on how intense coming storm will be

WASHINGTON - The peak of the next sunspot cycle is expected in late 2011 or
mid-2012 — potentially affecting airline flights, communications satellites
and electrical transmissions. But forecasters can't agree on how intense it
will be.

A 12-member panel charged with forecasting the solar cycle said
Wednesday it
is evenly split over whether the peak will be 90 sunspots or 140 sunspots.

The government's Space Environment Center in Boulder, Colo., tracks space
weather and forecasts its changes, which can affect millions of dollars
worth
of activities such as oil drilling, car navigation systems and astronauts.

Half of the specialists predicted a moderately strong cycle of 140 sunspots
expected to peak in October of 2011, while the rest called for a moderately
weak cycle of 90 sunspots peaking in August of 2012.

"We're hoping to achieve a consensus sometime in the next six to 12
months,"
said Douglas Biesecker, a space environment center scientist who is
chairman
of the forecast panel.

An average solar cycle ranges from 75 to 155 sunspots.

During an active solar period, violent eruptions occur more often on the
Sun,
the agency said. Solar flares and vast explosions, known as coronal mass
ejections, shoot highly charged matter toward Earth.

http://www. msnbc. msn. com/id/18317861/

Sunspot outlook 2012

The future of the sun appears spotty, according to some solar scientists.
By incorporating physical observations of the sun into a model, some
scientists
predict that the sun will boast more sunspots during its next cycle than
previous
estimates anticipated.

The Swedish 1-meter Solar Telescope imaged these sunspots in July 2002.
A new model predicts that about six years from now, the solar cycle will
peak
with higher numbers of sunspots than scientists previously estimated. Image
is courtesy of Royal Swedish Academy of Sciences.

To find out which model correctly predicts the next cycle, astronomers will
have to "wait a few years," Scherrer says. The next cycle is expected to
peak
sometime around 2012.

http://www. geotimes. org/may06/NN_Sunspot.html

Scientists Issue Unprecedented Forecast of Next Sunspot Cycle

The scientists have confidence in the forecast because, in a series of
test runs,
the newly developed model simulated the strength of the past eight solar
cycles
with more than 98% accuracy.

The Sun goes through approximately 11-year cycles, from peak storm
activity to
quiet and back again.

The Predictive Flux-transport Dynamo Model is enabling NCAR scientists to
predict that the next solar cycle, known as Cycle 24, will produce sunspots
across an area slightly larger than 2.5% of the visible surface of the Sun.
The scientists expect the cycle to begin in late 2007 or early 2008, which
is about 6 to 12 months later than a cycle would normally start. Cycle 24
is likely to reach its peak about 2012.

By analyzing recent solar cycles, the scientists also hope to forecast
sunspot
activity two solar cycles, or 22 years, into the future. The NCAR team
is planning
in the next year to issue a forecast of Cycle 25, which will peak in the
early 2020s.

"This is a significant breakthrough with important applications,
especially for
satellite-dependent sectors of society," explains NCAR scientist Peter
Gilman.

The NCAR team received funding from the National Science Foundation and
NASA's
Living with a Star program.

http://www. ucar. edu/news/releases/2006/sunspot.shtml

Is a New Solar Cycle Beginning?

The region that appeared on Dec. 11th fits both these criteria. It is high
latitude (24 degrees N) and magnetically reversed. Just one problem: There
is no sunspot. So far the region is just a bright knot of magnetic fields.
If, however, these fields coalesce into a dark sunspot, scientists are
ready
to announce that Solar Cycle 24 has officially begun.

Many forecasters believe Solar Cycle 24 will be big and intense.
Peaking in 2011 or 2012, the cycle to come could have significant
impacts on telecommunications, air traffic, power grids and GPS
systems. (And don't forget the Northern Lights!)
In this age of satellites and cell phones, the next solar cycle
could make itself felt as never before.

http://science. nasa. gov/headlines/y2007/14dec_excitement.htm?list951772

Solar Storm Warning

When the belt is turning "fast," it means that lots of magnetic fields
are being swept up, and that a future sunspot cycle is going to be intense.
This is a basis for forecasting: "The belt was turning fast in 1986-1996,"
says Hathaway. "Old magnetic fields swept up then should re-appear as big
sunspots in 2010-2011."

Like most experts in the field, Hathaway has confidence in the conveyor
belt model and agrees with Dikpati that the next solar maximum should be
a doozy. But he disagrees with one point. Dikpati's forecast puts Solar
Max at 2012. Hathaway believes it will arrive sooner, in 2010 or 2011.

"History shows that big sunspot cycles 'ramp up' faster than small ones,"
he says. "I expect to see the first sunspots of the next cycle appear in
late 2006 or 2007—and Solar Max to be underway by 2010 or 2011."

Who's right? Time will tell. Either way, a storm is coming.

http://science. nasa. gov/headlines/y2006/10mar_stormwarning.htm

Meanwhile, all eyes are on a promising little active region.
Will it become the first sunspot of a new solar cycle?

*** Stay tuned for updates from Science@NASA. ***

>>> Beberapa hari yang lalu Mama louren ditanya di sebuah TV swasta
>>> tentang 2012, beliau menjawab dia tidak dapat menembus 2012 dan
>>> setelahnya, dia hanya bilang akan ada NEW ORDE

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