1 senior - DOST Sci

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1
S Y 2000 - 2 0 0 1 V o l . 20 N o . 1
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REACHING FOR THE STARS
Can we possibly visit our neighboring galaxies?
ib er s,
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THE SPACE SHUTTLE: DEPLOYING A
SATELLITE PAYLOAD
The U.S. Space Shuttle happens to be an intrepid
space truck.
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ON TARGET: THE STEALTH AIRPLANE
How do you turn an entire plane invisible?
Th e Ed ito r
TWISTING IRON
Riding in a roller coaster is exciting. And
understanding the forces that governs its travel as
it glides along the rail may create more excitement.
R E G U L A R F E AT U R E S
3 Science & Technology News
5 Filipino Scientists and Inventors
BOARD OF ADVISERS
Violeta Arciaga, Jaime F. Bucoy
Jose C. Calderon, Victoria V. Cervantes,
Juanita M. Cruz, Belen P. Dayauon
Medical Facts and Fallacies
9 Livelihood Technology / I’d Like to Know
CONSULTANT
Merle C. Tan, Ph.D.
DIWA OFFICERS
10 Cyber World
14 Earth Care
16 Investigatory Projects
EDITORIAL BOARD
Saturnino G. Belen Jr. President
Lourdes F. Lozano Executive Editor
Amada J. Javellana Executive Vice President
William S. Fernando Managing Editor
Enrique A. Caballero,Reynaldo M. de la Cruz,
Alvin Fl. Julian Magazine Editor
19 Pseudoscience
Carlo F. De Leon,William S. Fernando,
Virgie B. Naigan Art Director
23 More Activities To Do
Jose Maria T. Policarpio, Elma L. Ropeta,
SilvanoC. Santiago Cover Design
Lourdes F. Lozano Vice Presidents
24 Mind Games
Jose Valeriano P. Linay Layout Design
Jun Mediavillo Illustrator
R
O
R
R
BATO BALANI for Science and Technology is published bimonthly by Diwa Scholastic Press, Inc. Bato Balani is one of Diwa’s Scholastics Enhancement Materials (SEMO). The SEMO
trademark refers to a new genre of scholastic publication, comprising a selection of premium - quality magazines for greater learning. All rights reserved. All articles in this publication may be reprinted provided
due acknowledgement is given. All communications should be addressed to THE PRODUCT MANAGER, G/F Star Centrum, Gil Puyat Ave., Makati City,Philippines, Telephone numbers 843-4761 to 66.
2
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Jurassic Spark:
I
T’S NOT QUITE Jurassic Park, but
it’s getting there.
Engineers on a Europe-wide project
are developing life-size robotic dinosaurs
that will walk around museums, chew on
plants and interact with visitors as if they
had just stepped off the prehistoric plains.
The designers want each 3.5-metre-long,
80-kilogram robotic iguanodon to be
autonomous, making its own decisions
about where to go and what to do. It will
approach inquisitive visitors, stare at them,
and even rear up on its back legs to browse
on the nearest potted palm tree.
“Usually you have to walk to museum
exhibits. In this case the exhibit walks to
you,” says designer Vassilios Papantoniou,
who works for the European Association
for Research in Legged Robots in Lamia,
Greece.
The robot will be built from
composite resins and aviation-grade
Electronic wizardry to
bring dinosaurs back to life
aluminum. Its movements
are based on what is
known
from
iguanodon fossils
and studies of
modern animals.
“A real dinosaur
has hundreds of
muscles,” says
zoologist R. McNeill
Alexander of Leeds
University, a scientific
adviser to the project. “So
we’ve
had
to
compromise.” The
major muscles are
replicated using
battery-powered actuators.
“We’ve got three in each leg,” he says. The
actuators are controlled by their own
microprocessors, which are linked to the
central processor that controls the beast. A
two-metre-long prototype has already been
completed.
The robot is being funded by the
European Union as part of a
project to liven up museums.
The designers hope to
complete a full-size
version by 2001.
European
Association for
Research in
Legged Robots
Which Came First:
Black Hole Or Galaxy?
A
TLANTA—A team of astronomers conducting a
systematic search for supermassive black holes
has discovered three more of the mysterious
objects lurking in the centers of nearby elliptical
galaxies. This brings the total number of
supermassive black holes definitively identified so far to 20. The
discovery was announced at a news conference held during the
American Astronomical Society Meeting.
“The formation and evolution of galaxies is intimately
connected to the presence of a central massive black hole,” said
Douglas Richstone,
leader of the research
team and a University
of Michigan professor
of
astronomy.
“Radiation and highenergy particles
released by the
formation and growth
of black holes are the dominant sources of heat and kinetic energy for
star-forming gas in protogalaxies.”
Richstone says the team’s conclusions are inferred from two
pieces of evidence. First, all or nearly all galaxies with spheroidal
distributions of stars (bulges in spirals) seem to have massive black
holes. The mass of these objects seems to correlate with the mass of
the central part of the host galaxy. “The ubiquity of this association,
as well as the correlation, points to a connection between the massive
black hole and the galaxy, and poses a ‘chicken and egg’ dilemma of
which came first,” Richstone said.
Second, comparisons of the history of star formation in the
universe with the history of quasars, conducted by other scientists,
reveal that quasars developed well before most star formation in
galaxies. Quasars are extremely powerful bright objects capable of
generating the luminosity of one trillion suns within a region the size
of Mars’ orbit.
University of Michigan
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3
Nomad Robot Finds
Meteorites in Antarctica
P
ITTSBURGH—Carnegie
Mellon University’s Nomad
robot, which conducted an
autonomous search for
meteorites in Antarctica from
Jan. 20-30, has successfully completed its
mission, examining more than 100
indigenous rocks, studying about 50 in detail
and classifying seven specimens as
meteorites.
An expert from the National Science
Foundation’s Antarctic Search for Meteorites
(ANSMET) program, who collected the
specimens after Nomad identified them in
the field, has concluded that five of the seven
are meteorites. The other two raise enough
questions about their composition to merit
further study. ANSMET is housed at Case
Western Reserve University in Cleveland.
Meteorites are curated at the Johnson Space
Flight Center in Houston and made available
to scientists around the world.
“Nomad has found and correctly
classified three indigenous meteorites insitu,” said Dimitrios Apostolopolous, a
systems scientist at Carnegie Mellon’s
Robotics Institute and project manager of
the Robotic Antarctic Meteorite Search
initiative. “The robot correctly classified
three other indigenous meteorites and
misclassified one as terrestrial rock. Nomad
achieved these results autonomously and
without any prior knowledge about the
samples.”
Most of the chondrites that Nomad
found are relatively common types,
composed mainly of rock with small
metallic infusions that probably originated
from asteroids. One achondrite meteorite
which Nomad classified as interesting is so
rare that the robot didn’t have the data in its
base to make a determination.
Carnegie Mellon University
U
sing a technique called neutral
atom imaging from a satellite
high above the North Pole,
researchers at the Department
of Energy’s Los Alamos National
Laboratory
are
developing pictures of
the magnetosphere, an
invisible magnetic
layer around the Earth.
These pictures will be
essential to a better
understanding of the
“weather” in space,
where a blast of solar
wind particles can
knock
out
a
multimillion-dollar
satellite.
Developing
what he calls “weather
maps for the radiation
belts,” Geoff Reeves
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Tracking Weather from the Sky
of the Los Alamos Space and Atmospheric
Sciences group and Mike Henderson of Los
Alamos’ Space and Remote Sensing
Sciences group devised a way to take rough,
low-resolution satellite data and create more
informative composite images of the solarwind-driven particles trapped in the
magnetosphere.
Used as still pictures or animated for
time-lapse movies, their pictures show the
ebb and flow of these particles as they near
the earth and are drawn around and down
the magnetic field lines. These images are
especially critical for understanding the
progress and structure of a space
phenomenon called geomagnetic storms.
Geomagnetic storms are the space
equivalent of hurricanes in the Atlantic. For
years scientists believed that geomagnetic
storms were made up of smaller
“substorms” which occur more frequently
and in isolation. But more recently scientists
have found that storms and substorms are
related — but distinctly different —
phenomena. This is similar to discovering
that hurricanes and thunderstorms are
related, but that a hurricane is not just a
cluster of thunderstorms or a larger, more
intense thunderstorm.
Future missions to the
magnetosphere will carry dedicated, Los
Alamos-designed, neutral atom imaging
instruments. These include NASA’s IMAGE
mission and TWINS, which will provide
the first stereoscopic images of the
magnetosphere.
Los Alamos National Laboratory University of California
Dr. Julian Banzon
Nuclear Chemist
D
r. Julian Banzon is a
man who dedicated
himself to the study
and applications of
chemistry. At age 23,
he was already a noted professor at the
University of the Philippines in Los
Baños. In 1957, he held the position of
chief scientist at the Philippine Atomic
Energy Commission (PAEC). Thereafter,
he became the first director of the
Philippine Atomic Research Center
(PARC).
He came back to UPLB in 1963,
and stayed there as chairman of the
Department of Agricultural Chemistry for
seven years.
The numerous awards, plaque, and
citations that Dr. Banzon received are
testimony to his achievements as a
scientist. The books and journal articles he
had written prove his ability as a
researcher and teacher. His active
participation in local and international
conferences, as well as his membership in
RABIES
Fallacy: One needs to submit
to rabies vaccination whenever a dog
scratches or bites him.
Fact:
The common practice
whenever a person is scratched or bitten
by a dog is to have anti-rabies shots.
Actually, the injection is for any
animal suspected of being rabid such
as cat, fox, rat or even rabbit. A rabid
animal is one afflicted with rabies.
An anti-rabies injection is not
always given whenever an animal
bites a person. The animal is first
sent to a veterinary clinic for observation.
The animal is kept in a place where
veterinarians can determine
whether or not it develops
rabies. If the animal
professional and scientific organizations
attest to his eminent stature as a chemist
and academician.
The science community is the
richer for scientists like Dr. Banzon. The
younger generation is indeed blessed with
the research finds and intellectual depth of
Dr. Banzon.
Source : Saplala, Vivas, and
Zafaralla. 1984. Profiles: Men and Women
of UPLB, College, Laguna: University of
the Philippines-Los Baños, Laguna.
is found to be healthy, no immunization is
necessary.
In case the animal cannot be found,
then the injection should be given as a
safeguard. We cannot take any chances that
rabies may develop as it has a very high
mortality rate.
The affected area, whether it was
broken or not, should be washed thoroughly
with soap and water. The washing should
last for approximately 10 to 20 minutes.
The rabies immunization vaccine is
very effective against rabies. There is no
danger of harmful side effects if somebody
is given the rabies vaccine even if the animal
in question does not develop rabies.
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5
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Y
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A
ssuming that the stars you see in the sky
on a clear night were reduced into the size
of the grains of sand, you can actually
hold them all in the palm of your hand.
However, the stars you see with your naked eye is
just a tiny fraction of the stars that are in the universe.
Scientists believe that the number of stars in the
Cosmos is more than all the grains of sand on all the
beaches of the world.
The universe is so unimaginably huge beyond
compare that most of it is empty of stars. Because of
the great distances that separate us from neighboring
stars, it will take years, even for light, to cross the
interstellar space. For instance, the nearest star
system to our Sun is Alpha Centauri with a distance
of 4.35 light-years (a light-year is the distance light
travels in a year, about 9.5 trillion kilometers). This
means light will take 4.35 years, as measured in our
time, to reach us. For light, however, time stands still.
The great void seems to put a clamp on man’s
dream to reach the stars. Moreover, Einstein’s special
theory of relativity puts a limit to the speed a material
object can attain — at lightspeed of 299,792,458
meters per second. But we have evolved with a brain
that possesses unlimited capacities to go around
what Nature has imposed upon us.
Travelling at or near the speed of light produces
paradoxes that run counter to common sense.
According to the special theory of relativity, light
travels at a constant velocity whether the source
is moving or not. This means you just cannot
add your speed to the speed of light.
Otherwise, you could attain any speed you want
by hitchhiking on a fast-moving mother vehicle.
Another rule codified by Einstein in his special
theory of relativity is that the laws of Nature must be
applicable to everybody anywhere in the universe.
This means that there is no fixed frame of reference
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from which to view the universe. Everything is
relative, depending on his position with respect to
another. Hence, the name relativity. No one can
travel at, or faster than, the speed of light. Nothing in
physics, however, prevents you from traveling as
close to the speed of light as you like, say at 99.99
percent lightspeed.
Can we travel close to lightspeed? Let’s make
a Gedanken experiment (a thought experiment, like
what scientists do, including Einstein, when trying to
explain the consequences of the relativity theory).
Imagine that you hitch a ride in a futuristic spaceship
that could accelerate up to lightspeed. As the
spaceship gains speed, you begin to see around the
corners of passing objects. You are facing forward in
the direction of motion but things behind you appear
within your forward field of vision.
From the standpoint of a stationary observer,
you appear red when you depart because light
reflected off you is shifted to the red portion of the
spectrum, and you appear blue when you return, a
process that could be explained by the Doppler
effect. If you approach the observer at almost the
speed of light, you will return shining brightly — your
invisible infrared spectrum will be shifted to the
visible wavelengths. The observer will see that you
become compressed in the direction of motion, that
your mass increases, and that your time slows down
— a consequence called time dilation. But from the
standpoint of the persons you are travelling with
inside the spaceship, neither of these effects occurs
to you.
But really, how close can we accelerate up to
lightspeed in practical terms? Dr. Charles Pellegrino
has an answer. In his book “Flying to Valhalla,” Dr.
Pellegrino proposed a 92 percent lightspeed for his
particular spaceship. Why 92 percent lightspeed?
According to him, 92 percent lightspeed is a realistic
velocity to aim for.
At 92 percent lightspeed, you will age at a rate
only one-third of the rest of the universe. To an
outside observer, the spaceship would appear to have
shrunk to less than half of its original length, and
would seem three times as massive, meaning three
times as resistant to acceleration. And from your
point of view, the entire universe is being compressed
ahead of the spaceship into a dome that occupies
only one-third of the sky.
Now as the spaceship accelerates further up to
lightspeed, to outside observers, the spaceship
appears to have no length at all (infinite
compression). Of course, the power required
demands infinite energy, which the spaceship could
never have. At lightspeed, you and your companion
including the spaceship, cease aging altogether. You
will traverse the length and width and breadth of the
universe in an instant.
These strange things happen because our
familiar ideas of space and time are no longer valid
when you approach lightspeed. Speed is distance
divided by time and since you cannot simply add
speeds near the velocity of light, space and time
must change. That is why you shrink and you hardly
age at all.
But in terms of practical engineering, is it
possible to travel close to the speed of light? Can we
build a kind of ‘lightship’ based on theories and
principles we have today?
Most of the time, revolutionary ideas are far
advanced for technology to catch up to. For instance,
in 1939, the British Interplanetary Society designed a
rocketship whose objective was to take people to the
Moon — using the technology of the 40s. However, it
was only three decades later that the Moon mission
was accomplished by Apollo 11 in 1969.
Today, we have preliminary designs for
starships whose ultimate design objective is to take
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us to the stars. One of these is Orion, a design that
calls for explosions of hydrogen bombs against an
inertial plate as a means of propulsion. The Orion
spacecraft seems practical from an engineering point
of view, but will produce vast quantities of radioactive
debris. Another design is Daedalus, using a nuclear
fusion reactor, assuming we could develop a fusion
engine in the next few decades. Orion and Daedalus
might travel at 10 percent light speed. A trip to Alpha
Centauri then would take 43 years, less than a human
lifetime. Such designs, however, could not travel close
enough to lightspeed for time dilation to become
important.
For voyages beyond the nearest stars,
starships with velocity approaching the speed of light
are in principle possible, though it would take our
technology thousands of years to catch up with the
ideas. An example of an interstellar starship is the
Bussard ramjet. The Bussard spaceship will have a
gigantic scoop to collect diffused matter in space
(mostly hydrogen atoms), and accelerate it into a
fusion engine, then eject it out.
Dr. Pellegrino has made feasibility studies for
a starship that could reach 92 percent lightspeed. His
design is an antimatter spaceship (he calls it the
Valkyrie) that uses antihydrogen as a propellant.
Antimatter is so far the ultimate fuel for propulsion
because one hundred percent of the mass of matter
and antimatter is converted to pure energy. (In
contrast, only one percent of the matter in a hydrogen
bomb is converted to energy during explosion.)
Ninety-two percent lightspeed is chosen
because, according to Dr. Pellegrino, at speeds
higher than this, particles of dust impacting against
the spaceship will explode like large hand grenades.
Furthermore, the amount of fuel required to accelerate
from 92 to a higher speed, say 95 percent lightspeed,
is twice as much as the acceleration from 0 to 92
percent.
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If you travel with the Valkyrie, the long space
voyage from the Solar System to Alpha Centauri will
take less than two years. With the Bussard
spacecraft, a trip to the center of the Milky Way
would take you 21 years. Of course, people on Earth
would measure an elapsed time of 30,000 years.
From the point of view of the travellers,
relativistic flight is surely a one-way ticket to eternity.
1.
Why is an antimatter spaceship suitable for
travelling close to lightspeed?
2.
From your own perspective, what happens to the
universe if you can travel at lightspeed?
3.
Why is 92 percent lightspeed significant from an
engineering point of view?
Doppler Effect – an apparent change in the frequency of
sound, light, or radio waves reaching an observer when
the wave source and the observer are in motion relative
to one another.
Interstellar space – the space between stars.
Thought experiment – a fictitious story used to illustrate a
scientific principle.
REFERENCES
Pellegrino, Charles. 1993. Flying to Valhalla. New York: Avon
Books.
Sagan, Carl. 1980. Cosmos. New York: Ballantine Books,
Random House, Inc.
Q:How fast is supersonic transport?
Imagine yourself travelling
faster than the speed of
sound. That is how fast
supersonic transport is!
A:
Travelling at speeds faster than sound is referred to as
Glisa F. Sanchez
Angeles University
Foundation
Angeles City
supersonic flight, from the terms super (meaning “over” or
“above”) and sonic (relating to sound waves). As compared to
sound waves that travels at about 1,220 kilometres per hour through air
at sea level, supersonic aircrafts can travel from one to five times the
speed of sound!
Gulaman
G
Bars
ulaman Bars are processed substance from agar
dhiella seaweeds. Used in different recipes, they
are especially prepared for delightful desserts.
People who live by the sea process gulaman
bars as a small- or medium-scale industry. You can
prepare your own gulaman bars just like the experts by following
this simple procedure.
Ingredients:
seaweeds
acetic acid or vinegar,
water
Procedure:
1. Gather the seaweeds and rinse them in clean water.
2. Dry them under the sun and soak overnight in clean water.
3. Add three litres of water and one teaspoon of acetic acid or
vinegar for every 100 grams of seaweeds.
4. Boil the mixture for one hour and filter it through a cheesecloth.
5. Boil again and repeat the same procedure to maximize gelatin
extraction.
6. Pour the collected substance called agar on aluminum molds
20 cm long and four cm deep. Allow the agar to solidify at room
temperature.
7. Cut into four cm wide bars and put inside a freezer for five days.
8. Thaw the bars in running water and dry them under the sun.
SENIOR
9
A
good computer programs starts from
As a convention, a flowchart begins on top
a good design. One way of designing
of the page and the end of the program is placed
a program is by using a method
at the bottom of the page. You need not know
called flowcharting. Flowcharting is a
programming code to flowchart. Simply use
method of showing the flow of a
ordinary language first and as you grow into
program using symbols. If the flowchart is designed
programming you will learn to use actual
properly, then it becomes very easy to create the
computer codes in your flowchart. For now it is
program code. Below are some conventional symbols
sufficient to use simple words (See the sample
used for flowcharting.
flowcharts).
10
Process Box
The rectangle represents an action, computation or process that
needs to take place.
Input/Output
Box (I/O Box)
The parallelogram is used when a value has to be entered or
something has to be displayed on screen.
Decision Box
The diamond is used to signify that a decision has to be made.
Each decision can have only two possible outcomes, true or false.
Flowlines
These arrows point in the direction of the next action to be performed.
Think of these as directional signs that point you in the right way.
Connectors
These circles indicate a “jump” in the program. Sometimes your
program needs to jump to another part of the flowchart.
Terminal
Symbol
These ovals will signify the beginning or end of the program. Simply
write START or END inside the oval.
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www.batobalani.com
START
START
Would you like to become
Interactive?
Enter
2 nos.X,Y
Input A,B
X+Y=Z
SUM = A + B
Display C
Print SUM
END
END
These are two flowcharts for
the same program. The flowchart on
the left uses plain English to
explain what the program will do.
The flowchart on the right uses
actual programming code from
BASIC* to show what the program
will do. Try to understand both
flowcharts. Can you guess what the
program does?
*Beginners All-purpose
Symbolic Instruction Code (BASIC)
B
atobalani magazine is now on the internet. In the
Batobalani website are archives of current and past
issues as well as a variety of activities and additional
topics for the inquisitive student of science. In
subsequent issues of the magazine, we will discuss the
different activities we have prepared for you.
One useful feature in the website is a feedback or
response page. This allows you to send us your comments
and even contribute your own article. By simply typing it in or
pasting it on the dialogue box.
You will need to have a computer unit with a modem and
a valid account with any authorized internet service provider
(ISP) such as Mozcom, Infocom, Philonline, or any other ISPs.
To write us, simply follow these steps:
1). On your computer, open up an internet browser
program. For most of you, this would be Microsoft’s Internet
Explorer or Netscape’ Navigator’s program. Make sure you are
connected to your Internet Service Provider.
2). On the address window of your browser program, type
www.batobalani.com, then hit the “enter” key.
3). You will see Batobalani’s homepage on your screen.
Also, you will see a menu of sections you can go to on the
lower right side of the screen. Choose “Feedback” and click
the left button of your mouse.
4). The feedback page will show you different boxes for
you to fill in. Go ahead and fill the information. You may skip
the items that you cannot fill up. Then on the Message box,
type in your message or your opinion or even a simple “hello.”
5). Once you’re finished with your message, hit the
“send” button by clicking the left button of your mouse. Presto!
You’ve sent us your message.
There are many other interesting things you can do
inside Batobalani’s website. Feel free to explore. If you have
questions or need further instructions, why don’t you try
sending it to us using the feedback page. We hope to hear
from you soon!
WSF
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11
A
n artificial satellite is any object placed into
orbit around the earth and used for a variety
of scientific and technological purposes.
The former Union of Soviet Socialist
Republics (USSR) launched the first artificial
satellite, Sputnik 1, on October 4, 1957. The first United
States satellite, Explorer 1, was launched on January
31, 1958, and was instrumental in the discovery of the
radiation belts around the earth.
In the years that followed, several thousand
satellites were launched, monopolized by the United
States and the former USSR in a battle for space
supremacy until 1983, when the European Space
Agency began launching from a space center in French
Guiana. On August 27, 1989, for the first time in
aerospace history, a privately owned rocket was used
to launch a satellite. The rocket, built and launched by
a U.S. company, placed a British television broadcasting
satellite into geosynchronous orbit.
Satellites are usually placed into orbit by
multistage rockets. In part to reduce satellite launching
costs, the National Aeronautics and Space
Administration (NASA)
uses the space shuttle to
carry satellites in its cargo
bay and launch them into
orbit.
The minimum initial
velocity required for an
object to escape the
gravitational pull of an
astronomical body, and to
continue traveling away from
it without the use of
propulsive machinery is
called escape velocity. The
escape velocity is usually
given in terms of the
surface-launch velocity, disregarding aerodynamic
friction. Objects traveling at less than 0.71 × 11.2 km/s
(the escape velocity of Earth) cannot achieve a stable
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orbit. At such velocity, the orbit becomes circular, and
at higher velocities, the orbit becomes elliptical until
escape velocity is reached. Then, the orbit becomes
parabolic. (Escape velocity is thus also known as
parabolic velocity).
The escape velocity of an object from a spherical
astronomical body (like the Earth) is proportional to the
square root of the mass of the body divided by the
distance between the object and the center of the body.
A space shuttle designed to leave the earth as a
vertically launched rocket must weigh at least 2 million
kg with 3 million kg of thrust from its multiple propulsion
systems.
The two solid rocket boosters (SRBs), with a
combined thrust of some 2.6 million kg, will provide most
of the power for the first two minutes of flight. The SRBs
will take the space shuttle to an altitude of 45 km and a
speed of 4973 km/hr before they separate and fall back
Jerard F. Beltran
into the ocean to be retrieved, refurbished, and prepared
for another flight.
After the boosters fall away, the three main engines
continue to provide thrust. These
engines are clustered at the rear
end of the orbiter and will have a
combined thrust of almost
540,000 kg. The space shuttle’s
liquid-propellant engines will be
the world’s first reusable rocket
engines. They fire for only eight
minutes for each flight, just until
the shuttle reaches orbit, and are
designed to operate for 55 flights.
The engines are very large—4.2
m long and 2.4 m in diameter at
the wide end of the cone-shaped
nozzle at the rear of the orbiter.
Another propulsion system takes over once the
space shuttle’s main engines shut down as the ship
approaches the altitude at which it will begin orbiting
around the earth, known as the orbital insertion point.
Two orbital maneuvering system (OMS) engines,
mounted on either side of the aft fuselage, provide thrust
for major orbital changes. For more exacting maneuvers
in orbit, 44 small rocket engines (known as the reaction
control system), clustered on the shuttle’s nose and on
either side of the tail, are used. They have proven
indispensable in performing the shuttle’s important work
of retrieving, launching, and repairing satellites in orbit.
The giant, cylindrical, external fuel tank, with a
length of 47 m and a diameter of 8.4 m, is the largest
single piece of the space shuttle. It fuels the orbiter’s
three main engines. During launch, the external tank
also acts as a support for the orbiter and SRBs to which
it is attached. Made from aluminum alloys, the space
shuttle’s external fuel tank is the only part of the launch
vehicle that currently is not reused. After its 1.99 million
liters of fuel are consumed during the first 8.5 minutes
of the flight, the external tank is jettisoned from the
orbiter and breaks up in the upper atmosphere, its pieces
falling into remote ocean waters.
After placing the satellite in orbit, the orbiter
segment returns from space—withstanding the intense
heat when entering the earth’s atmosphere. Flown by
the shuttle crew much like an aircraft, the shuttle lands
horizontally on a conventional airport runway.
1). What are the benefits of satellites?
Orbit — the path an object takes as it travels around another
object.
"Satellite, Artificial,” Microsoft® Encarta® 97 Encyclopedia.
© 1993-1996 Microsoft Corporation. All rights reserved.
"Escape Velocity,” Microsoft® Encarta® 97 Encyclopedia. ©
1993-1996 Microsoft Corporation. All rights reserved.
"Space Shuttle,” Microsoft® Encarta® 97 Encyclopedia. ©
1993-1996 Microsoft Corporation. All rights reserved.
SENIOR
13
Save Our Seas:
A Crusade for
Coral Reefs
Mary Ann Aleli V. Barbieto
O
n September 11, 1992, a terrible
Their mission -
hurricane swept through Hawaii’s
“To preserve, protect,
island of Kauai. Surprised that such
and restore the health
destruction could happen in such a
and well-being of the
short time, three people got together and organized a
world’s oceans for
truly dynamic group whose main purpose was to
future generations.” –
protect and preserve the fragile marine ecosystem.
was integrated into the
These three were Carl Stepath, the owner and
laws of the state of
operator of Nawiliwili Marine and Sailboards Kauai;
Hawaii within the next
Teresa Tico, a lawyer who was into bodysurfing, yacht
year, and with much
racing and windsurfing; and Nicholas Barran, a
enthusiasm, they set
computer programmer who also loved yacht racing.
out on their first
Through the efforts
project. This was the
of these
Open Seas Recycling Program, which they launched
concerned
during the 1993 Trans Pac Yacht Race, a racing
citizens, Save
competition where yachts ran from the coast of Los
Our Seas
Angeles to Honolulu. The board of directors who held
(SOS), was
the contest were thrilled with their proposed project,
born.
14
SENIOR
Our
and immediately decided that recycling should not
participate in this “adopt a reef” program, where the
only be a part of a program, but a requirement for
students survey corals, marine life, and measure
those who were competing in the race. They added a
water quality, then report back to SOS via the
new regulation that all trash must be kept on board,
Internet. These results are then compiled and used
and all recyclable materials - paper, aluminum and
for future reference in finding ways to save our
glass - were the responsibility of the racers and must
speedily vanishing coral reefs.
be recycled before they reached the finish line. At
These children become responsible for the reefs,
the end of the race, the project proved to be so
and are then called “reef keepers.” SOS hopes that
successful that it was adopted by yacht clubs in
these children will realize how important it is to care
Japan and Australia.
for our coral reefs and our entire ocean ecosystem.
The Philippines is taking part in another project
sponsored by Save Our Seas, “Ocean Pulse.” Its
aim is to educate the community about our coral
reef’s complex ecology though direct interaction with
the living, breathing corals that surround our
Through their hands-on experience, they learn how to
be more careful in dealing with nature.
Do you want to become a part of SOS and
contribute to the preservation and care of our oceans?
You can visit their website at:
archipelago. This project involves students from all
over the country and began in their native Hawaii,
where they enlisted the help of seventh and eighth
http://hookomo.aloha.net/~sos~/ . You can also
write to them at sos@aloha.net.
graders whose schools have volunteered to create
Resources: SOS homepage
databases for Save Our Seas. Schools who
SENIOR
15
I N
C O O P E R AT I O N
W I T H
T H E
DEPARTMENT OF SCIENCE AND TECHNOLGY
UV IRRADIATION TO
CONTROL GROWTH OF
ASPERGILLUS FLAVUS IN
COPRA
ABSTRACT:
control. A. flavus growth in copra was
alfatoxin tolerance level of 0.2 parts per
then determined. Previously dried copra
million (ppm) for copra meal and 20 parts
of controlling the growth of Aspergills
(‘kokum”) were moistened, inoculated
per billion (ppb) for coconut oil.
flavus in copra with ultraviolet (UV)
with A. flavus, then exposed to 15- minute
radiation.
UV irradiation. The growth of the fungus
This study explores the possibility
Pure cultures of A. flavus were
prepared in nutrient agar. These were
exposed to different durations of exposure
to UV radiation (quartz tube-mercury
vapor source, wavelength approximately
240nm-270nm): 1, 3, 6, 10, and 15
minutes. The growth rate of the fungus
was observed in three replications. Among
the five treatments, UV radiation of 15
minutes controlled the growth of the
fungus to the greatest extent. This could
be due to the damage on the DNA which
led to abnormal physiological functions
and death of the cell.
irradiation inhibited up to 92% of the
fungal growth.
INTRODUCTION
A few years ago, the Philippines
lost much of the United States market for
SENIOR
fungus, Aspergillus fluvus. It has been
found to cause cancer in animals ingesting
it. It is very potent in this respect with no
more than 0.05 ppm capable of inducing
illness. Aflatoxin is also a natural
mutagen.
The control of aflatoxin
copra because it took very little notice of
contamination in copra depends mainly on
the restrictions imposed on copra
the inhibition of the growth of A. flavus.
contaminated with aflatoxin. Last
Growth of A. flavus is enhanced by
December 1990, the European Economic
factors such as high relative humidity,
Community (EEC)— which absorbs 46.6
high moisture content and warm
percent of the country’s coconut oil export
temperature.
and 30 percent of copra— implemented a
policy to standardize aflatoxin (Lorito,
The effectivity of UV radiation to
16
was observed after five days. 15-minutes
Aflatoxin is produced by the
1990). This regulation imposes an
This study aimed at determining the
relative sensitivity of A. flavus to highenergy radiation. Specifically it
determined the effects of UV on the
high-energy radiation such as ultraviolet
growth rate of A. flavus.
rays, X-rays and gamma rays. Radiation
REVIEW OF LITERATURE
causes dimerizations (linking) and
synthesis is proceeding. Increasing the
causing metabolic abnormalities. This
fungus classified under Division
prevents further growth or reproduction of
Eumycophuta, Class Ascomycetes. It
fungi in copra.
present. Because of this, its growth in
agricultural products is difficult to control.
Moreover, the spores of the fungus are all
around so that the possibility of
contamination is great (Gloria, 1989). The
presence of A. flavus is undesirable
especially in copra, peanuts, corn,
soybeans and potatoes.
In copra, contamination can start
after harvest when the nut is broken on the
ground and the coconut meat scooped
from the shell. Placing the copra in sacks
which may be laden with. A flavus spores
further increases the chances of
contamination.
Contamination is usually
dose of UV light both increases the
probability of mutation per unit of time
(Fincham, 1965).
usually grows in moist warm
environments where carbohydrate is
The mutagenic effects of UV
depends on the stage at which protein
ionizations in th DNA of the fungus
A. flavus is a brownish-green
(Sylianco, 1983).
Low doses of UV delays budding
or germination of the fungus. Cells
MATERIALSAND METHODS:
A. flavus used in this study was a
irradiated with UV of wavelengths ranging
from 280nm – 380 nm did not begin to
pure culture derived from the RP-UK
bud as early as the controls – in some
Aflatoxin Research Project of the
cases they never budded. A small
Philippine Coconut Authority, Mintal,
percentage of spores which survive
Davao City.
exposure to UV radiation may produce
A quartz tube-mercury vapor
mutants.
source from the Ateneo de Davao
During UV irradiation the normal
University with wavelength ranging from
hydrogen bond-interaction between bases
240nm to 270nm was used. Treatment
are cleaved. This may lead to interruption
was done on A. flavus for 1 min. (T1), 3
of replication, or division may stop short
mins. (T2), 6 mins. (T3), 10 mins. (T4)
or may proceed incorrectly with an altered
and 15 mins. (T5)
base sequence. Therfore, the effects of UV
The other materials were:
radiation on living tissues is a
consequence of its effect on the bases of
10 mL coconut extract
DNA and RNA (Sylianco, 1981)
10g dextrose powder
minimized if the coconut is dried within
four hours after splitting. Drying in the
“tapahan” is usually favored over sun
drying because it reduces the moisture
content to about 10-15 percent in a short
time. If the copra is properly dried, the
possibility of contamination is nil. But
again, the chances of contamination
increases during storage, when the
Changes produced by radiation
100g “kokum”
may be a direct effect on the molecules
where the energy has been absorbed, or
700 mL distilled water
indirect effects in which molecular
changes are bought about by the chemical
1 pressure cooker
reactions of free redicals produced as
1 inoculating set
primary effect radiations (Lea, 1955).
Calculations shows that radiation
humidity inside the storehouse is high and
which destroys perhaps only one molecule
air circulation is inadequate (Gloria,1989).
in a million can have profound biological
A. flavus could be susceptible to
18 petri dishes
1 improvised inoculating box
Part 1.
5 mL of agar with coconut extract
consequence and can kill the cell
SENIOR
17
to the A1, A2, and A3 setups. B1, B2 and
were poured into 18 petri dishes at a depth
sq. cm/day, with about 90% mutation.
B3 were made as control.
of about 2mm. The dishes were covered
and sterilized for about 15 minutes. They
were then placed in an inoculating box and
were allowed to cool and solidify.
The coconut-agar media were
innoculated with A. flavus spores using
Observations were made on the
five days.
Gloria, M. “Aflatoxin and Copra”.
contaminated with A. flavus was
determined. The percentage contamination
Southern News Scope. August 1989. Vol.
was then calculated. From the difference,
2 p.8
the percentage inhibition was determined.
the disc method and were placed in a dark
chamber with 29 to 30oC temperature for
SELECTED REFERENCES:
fifth day, after which the mass of the copra
RESULTSANDANALYSIS
Gincham, J.R.S. 1965. “Fungal
Genetics”. Blackwell Scientific
publications.
The average growth rate of A.
The growth rate of A. flavus was
determined in sq. cm. Counting was
performed using a graphing paper with a 1
sq. cm. grid placed underneath.
flavus in the control and in treated
medium are as follows:
University Press.
From day 1 to day 2, the fungus in
the controlled setup covered a very much
Growth rate was determined by the
formula:
Lea, D.E. 1963. “Actions of
Radiation on Living Cells”. Cambridge
Lonito, D.L. 1990. “Behind the
bigger area as compared with those in T1,
Aflatoxin Scare”. Mindano Farmers
T2, T3, T4 and T5. However, its growth
Journal.
tapered off after the second day. The
Sylianco, C.Y. 1981. “Modern
s = a/d
fungus in T1, T2, T3 and T4 covered a
Biochemistry” Philippine Graphic Arts,
where:
smaller area during the first two days. It
Manila.
then accelerated after the second until the
a is the area in sq. cm
fifth day. The setups in T5 showed least
growth of the fungus.
d is the time in days
s is the rate in sq. cm/day
Microscopic examinations of the
irradiated molds were conducted every 24
hours.
Irradiation of 1,3, and 6 min.
duration caused little damage to A. flavus.
10 min. exposures caused greater damage
to A. flavus. 15 min. exposures actually
inhibited the growth of A flavus on
Part 2.
experimental copra samples, by about
Six sets at 20g each of “kokum”
dried copra were soaked in water for 5
91.8%.
The fastest growth rate was
minutes, then drained and placed in petri
observed in the control, 8.3 ± 0.6 sq. cm/
dishes. The dishes were labelled A1, A2,
day, followed by those exposed for 1 min,
A3, B1, B2, and B3. The copra samples
3 min, then 6 min. and 10 min. Those
were all inoculated with A. flavus spores.
treated for 15 min. showed only a total of
A 15 minute irradiation was given
18
SENIOR
12.5 ± 3.1 sq. cm or a growth rate of 0.83
UV Treatment
Control
1 min.
3 min.
6 min.
10 min.
15 min.
Growth rate
(sq. cm/day)
8.3 ± 0.6
5.4 ± 0.5
4.8 ± 0.6
4.5 ± 0.6
2.7 ± 0.6
0.83 ± 0.5
The
Philadelphia
Experiment
Joe Bert G. Lazarte
Remember the 1984 film The Philadelphia Experiment?
T
he movie was based on an alleged United
States Navy experiment(Project Rainbow)
done on October 28, 1943. According to
legend, the destroyer USS Eldridge was
made invisible, dematerialized, and
teleported from Philadelphia, Pennsylvania, to Norfolk,
Virginia, and back again to the Philadelphia Naval
Yard.
The experiment allegedly had such terrible sideeffects, such as making sailors invisible and
eventually going mad, that the Navy quit exploring this
exciting new technology. The experiment was
allegedly done by Dr. Franklin Reno as an application
of Einstein’s unified field theory. The experiment
supposedly demonstrated a successful connection
between gravity and electromagnetism:
electromagnetic space-time warping.
One Carlos Allende, or Carl Allen, claimed that
he witnessed the experiment. In fact, he was one
major source of stories about the experiment, who,
as further writings and probings into his
background surfaced, later proved to be a conman who weaved the hoax.
Surprisingly, one retired military
man, Alfred Bielek, picked up where
Allen left the story. Bielek’s memories
apparently came back to him after
watching the 1984 film, coming up with
more detailed explanations of the
experiment. He co-authored a book,
The Philadelphia Experiment and
Other Conspiracies, which merely
rehashes the usual stories of CIA
plots, government conspiracies, secret
meetings with aliens, trips to Mars,
visits from the Men in Black, etc. He
also came out with a video in which he
presented himself as someone who was part of the
team that conducted the experiment, time-traveled in
1943 to 1983 during the experiment and lived to tell
the story, only to be harassed by the U.S. government
for his troubles.
But in the face of these myths, the Navy came
out with its official documents that take note of the
story’s salient points, such as: (1)there was no such
project as the Philadelphia Experiment, no
experiments into invisibility. There were projects codenamed Rainbow, but they were warplans to defeat
Italy, Germany, and Japan; (2) The Office of Naval
Research, under which the experiment was
supposedly conducted, did not even exist until 1946;
(3) The U.S.S. Eldridge was never even in
Philadelphia during the fall of 1943, and the deck log
that proves this is available on microfilm via the web.
What the Navy documents do add,
moreover, are some valid points on the subject
of degaussing, which is a process, and when
correctly done, makes a ship “invisible” to the
sensors of magnetic mines, but remains
visible to the human eye, radar, and
underwater listening devices.
They also note that while
experimenting with 1,000 hz generators
in the 1950s, “the higher frequency
generator produced corona discharges,
and other well-known phenomena
associated with high frequency
generators,” which can be exciting when
viewed.
This sounds plausibly like the
genuine seed for the story, which people
like Jessup, Carl Allen, and Bielek weaved
stories from. Such is the stuff urban
legends are made of.
SENIOR
19
P H Y S I C S
On Target: The
Stealth Airplane
R
adar, or radio directing and ranging, is
one of the most vital devices needed by
the defense department of any country.
It is very valuable in tracing the position
of enemy ships and airplanes during wars and conflicts.
But since its invention however, a lot of research and
technology has been developed to counter-attack it. One
of this is stealth technology.
The main purpose of this system study is for antidetection.
This technology had already begun
development in
World War II when snorkels of German U-boats
were coated with radar- absorbing materials. Since then,
researches were done in secret laboratories to determine
other ways radar detection can be avoided or at least
minimized. Special attention was given to aircrafts.
In the early 1970s, The US Department of Defense
and US Air Force collaborated for this work. Studies
were conducted and bore fruitful results. These studies
20
SENIOR
ranged from chemistry and composite materials to
likewise strategically placed all over the plane.
computer-aided design and manufacture, all aiming for
Suggested paint color is black in order to elude visual
the reduction of the identification of future-weapons
detection since a the stealth airplane is designed to
delivery and surveillance systems used in air warfare.
operate by night. However, further research is made
With this quality, any type of aircraft will have a higher
concerning visibility in order to make the plane invisible
chance of survival in the battle arena.
even during daytime.
The first process in making a stealth
Exhausts from an aircraft are also detectable by
airplane is to create a special design for
radar. Scientists in stealth research also have given
the aircraft. One may notice the unique
this keen focus. Since the engine emits
geometry of a Northrop B-2, for example. To
infrared or heat-source radiation, the
understand this better, it is necessary to know
stealth’s exhaust sections are
how radar works. Regardless of whether it is
flattened into thin, long slots that
airborne or ground-based, the radar ‘sees’ its
are layered with cold air. Direct
target object within a range of 30 degrees around
injections of powerful chemical
its own horizontal plane by emitting radio beams
coolants are then applied to the exhaust
and waiting for them to bounce back upon contact
gases, so that they would mix with the
with the object. It can then measure the length that
outside air unnoticeably.
the beams had traveled and equate it as the
distance of the object from the radar source, thus
determining the target’s position.
And yet, along with this great innovation
comes a great price: Both in dollars and performancewise. Each of the first fifteen Northrop B-2 costs $776
This suggests that a stealth aircraft’s design needs
million, making it the most expensive warplane built in
to be as flat as a straight line as possible when viewed
the last few years. The stealth program has amassed a
horizontally. If it did need to curve however, it ought to
total of $43 billion expenditures to date, just by making
be the double-curvature type so that reflection can be
an aircraft that cannot be detected by radar. Other
minimized. Known as reflective faceting, the plane is
problems encountered aside from the high cost is its
designed to have slabs or facets having angular relativity
lower acceleration rate compared to ordinary fighter
so as to divert the radio beams away from the source.
planes because it had to use turbofan engines with no
Another process in anti-radar detection is coating
the stealth with radar-absorbing materials, namely
pyroceramics, polyurethanes, silicones, and rubber and
carbon compounds. Several corner reflectors designed
afterburners. Add to that is the plane’s need of a
repainting job after every mission.
Microsoft® Encarta® Encyclopedia Deluxe 2000. © 1993-1999 Microsoft
Corporation.
to catch, trap and scatter radio frequency energy are
SENIOR
21
P
H
Y
S
I
C
S
TWISTING IRON
TWISTING IRON
n many theme parks around the globe, one of the
most sought-after ride is the roller coaster. In
Laguna, the Enchanted Kingdom theme park
offers the mind-numbing “Space Shuttle,” a 1minute ride that takes you through two 360 degree
loops and varying side-twists and turns. Then you go
through the whole thing again, this time
backwards! Most kids find the ride fun
and enervating. The serpentine
iron rail gleams like some giant
torture instrument in the
daytime. And the shrieks
and screams from those in
the hurtling train seems to
confirm that.
I
“wanting” to break out of the loop. Many brave kids
try to lift their arms above their heads as they turn
upside down going through the 360 degree loop. They
are trying to resist the action of the centrifugal force.
But roller coasters are
governed by natural laws that
permit its riders to have fun while
seemingly courting disaster with its neck-breaking
speed and jaw-breaking twists and turns.
There are other roller coaster
rides in the Philippines. The next time
you try one, try to observe the various
forces that act on your body as it turns,
twists and turns upside down. It is best
to remember to keep your sunglasses,
hat and other paraphernalia tucked in
securely in your pockets before they
are wrested from you by the various
natural forces that govern the
movement of the
roller coaster.
As the shuttle’s wheels clamp down against the
rail in a sharp sideways turn, the friction between the
tires and the rail must sustain sufficient sideways
force to provide the necessary centripetal force for
curved motion. Centripetal (“center-seeking”) force is
the radial force required to keep an object continually
diverted in its path so that it travels in a circle. In this
instance, centripetal force keeps the shuttle along a
curved path as it travels along the rail.
Centrifugal (“center-fleeing”) force refers to the
same phenomenon as centripetal force but may be
considered the equal but opposite reaction to the
action of the centripetal force. The roller coaster
shuttle hurtling along the 360 degree vertical loop of
the rail, for instance, will manifest centrifugal force by
22
SENIOR
Centrifugal force is proportional
to the mass of the object it is
exerting upon. It can simulate
earth’s gravitational force.
That is why, in sharp turns
and the full vertical loop, the
rider feels weighed
down and feels his
head and arms being
drawn towards the
floor of the shuttle.
Surface Tension
T
hroughout a liquid, the molecules are attracted to one another. At the surface
of the liquid, the forces of attraction lead to an effect called surface tension.
The two soap-film tricks shown here demonstrate surface tension action.
Procedure
Materials
liquid soap
glass
water
wire
thread
The jumping wire
1. Put some liquid soap in a glass and add water to
make a strong, soapy solution.
2. Bend a piece of wire to form a rectangular frame and
handle, as shown above. The frame should be small
enough to fit into the glass.
3. Dip the frame into the solution and then remove it.
The frame should now be covered with a soap film.
4. Hold the frame horizontally and place a straight piece
of wire across it.
5. Break the soap film on one side of the wire with your
finger. Forces of surface tension on the other side will
pull on the wire, causing it to jump from the frame.
The magic loop
1. Tie a short piece of thread to form a loop.
2. Form a soap film on a wire frame, as previously
described. Carefully place the thread on the film.
3. Now break the film inside the loop. Surface tension
forces around the loop will put it into a neat circle.
SENIOR
23
And the law says…
THERMODYNAMICS BOX
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Look for all the hidden words listed below
from the letter box that are related to the study
of thermodynamics.
C
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CONVECTION
ISOBARIC
ENTROPY
POWER
LATENT HEAT
PRESSURE
RANKINE
COMBUSTION
ENGINE
IDEAL GAS
ADIABATIC
CARNOT CYCLE
TEMPERATURE
WORK
C R O S S W O R D
Across
1 Not bottom
3 Where bees live
4 House
7 Extraterrestrial
(abbr.)
9 _ _ _ic_e, small
bones in the ear
10 _ _us, presiding
Greek god
12 Unit of power
13 Charged particles
14 Refers to ear
17 Oxygen (symbol)
19 _ _ _ _zoic, a
geologic era
21 Small opening
22 milli_ _ _ _ , a crawling
organism with a
thousand “limbs”
24 Po_ _ , to transfer a
liquid
25 Not right (direction)
28 Electromagnetic
29 Story
30 Uranium (symbol)
31 Self-fulfilling love
32 Stiff stick
24
1
2
7
7
4
8
3
5
6
9
10
11
16
17
13
12
14
15
18
18
15
16
19
19
21
24
22
25
26
27
SENIOR
23
28
30
29
31
20
32
Down
2 Source of energy which
are triggered off by light
3 Airbone vehicle, capable
of vertical take off
5 Osmium (symbol)
6 Miss/Mrs (abbr.)
7 Female sheep
8 Tantalum (symbol)
10 Zinc (symbol)
11 _ _ _phagus, food tube
15 Tellurium (symbol)
16 Not out
18 Address of respect to a
nun (Sp.)
20 Fermented drink
21 Free from contaminants
23 Electromagnetic
unit
(abbr.)
26 Indicates early period of
time
27 From (abbr.)