Lasers Hide Earth from Hostile Aliens? - Two astronomers
from Columbia University are suggesting that the human race
could use lasers to hide our planet from alien invaders.
One of the ways scientists identify planets is by watching
for how they dim the light of their parent star as the planet
passes in front of it. If aliens are doing the same thing
Professor David Kipping and graduate student Alex Teachey
think Earth could be hidden by using lasers to fill in the
missing light. Since it might be possible to tell what the
atmosphere of planet looks like by seeing what colors of
light are missing when the stars light goes though the planets
air, it might also be possible to make Earth's inviting
environment look like a dead planet by just using the right
laser frequencies. Skeptics of this idea note that for it
would only work if you knew the exact location of the aliens.
Also it is possible that the transmission of terrestrial
radios and TV signals may have already tipped off any curious
extra-terrestrials to our presence
Images Used to Find Norse Settlement - Scientists have
used satellite images from space to locate what looks like
a Viking settlement in North America. Space archeologist
Sarah Parcak from the University of Alabama discovered evidence
of iron-work at Point Rose in Newfoundland, Canada, then
excavations at the site confirmed that the inhabitants were
gathering iron from bogs and smelting it into tools and
weapons, a process that Native Americans were not aware
of. This makes the site only the second confirmed location
of a Norse settlement in North America. It is estimated
that the Vikings crossed the Atlantic and had settlements
in North American about 500 years before Columbus made his
Reveals Dead Language - Archeologists are excited about
a slab (or stele) found in an excavation of an ancient temple
in Tuscany, northern Italy. They believe it is written in
Etruscan, a long dead language of which we know little.
What is known about it comes from inscriptions found on
graves and other funerary items which are very brief samples.
The slab is almost 4 feet (1.2 meters) in height and over
2 feet (0.6 meters) in width and weighs 500 pounds (225-kilograms)
and has a long inscription on it. While only 70 characters
are currently visible, due to the centuries of weathering,
scientists hope by using lasers and other advanced equipment
they can make the rest of the inscription visible. Project
leader Gregory Warden said "we hope to make inroads into
the Etruscan language," noting, "long inscriptions are rare,
especially one this long, so there will be new words that
we have never seen before."
Gets New Super Laser - The Department of Energy's SLAC
National Accelerator Laboratory at Stanford will be getting
a new X-ray laser. The laser, which is 10,000 times brighter
than the original one and fires 8,000 times faster, (up
to a million pulses per second) will be the most powerful
X-ray laser in the world. The project, known as LCLS-II
(Linac Coherent Light Source) will sharpen the view of the
device for experiments allowing it to observe the ultrafast
and ultrasmall. SLAC Director Chi-Chang Kao said, "Our lab
has a long tradition of building and operating premier X-ray
sources that help users from around the world pursue cutting-edge
research in chemistry, materials science, biology and energy
research. LCLS-II will keep the U.S. at the forefront of
Quote of the Month -"Understanding
the history of matter and searching for its most interesting
forms, such as galaxies, stars, planets and life, seems
a suitable use for our intelligence." - Robert
New at the Museum:
Eiffel Tower - When construction was first started in
1887, it was called "useless and monstrous" as well as a
"ghastly dream." Yet this structure has become one of the
most beloved icons of a major city and a wonder of the age
of steam. > Full
Packaderm vs. Little Sport Device -Could an elephant
have the same momentum as a golf ball? - Anonymous.
easiest way of thinking about momentum is the force necessary
to stop a moving object. It involves both the mass of the
object and speed of the object. Technically, in classical
physics, this can be expressed as the mass of the object
mulitpled by its velocity. The formula is:
P is the momentum, m is the mass and v is the veolocity.
we had and elephant that weighed 7200 Kg (about 15840 pounds)
running at 1 meter per second, the elephant would have:
kg m/s = 7200kg 1m/s
means that 7200kg is the mass, 1 meter/second (m/s) is the
velocity and 7200 kg m/s ("kilogram meters per second")
is the momentum.
It is easy to see a trivial situation where any two objects,
no matter the size of their mass, would have the same momentum.
Any object that has no veolocity has no momentum. So both
an elephant and a golf ball would have the same momentum
if neither were moving.
are also cases where the elephant and the golf ball could
have the momentum even if they were both moving.
Imagine our 7200 kilograms elephant from above and a golf
ball weighing .046 kilograms. If we set up the equation
with the elephant on the left and the golf ball on the right:
= p = mv
1m/s = 7200kg m/s = .046kg V m/s
just need to solve for the V, the velocity of the golf ball:
1m/s = 7200kg m/s = .046kg 156521 m/s
can see that an elephant running along at 1 meter per second
has the same momentum as a golf ball moving at 156,521 meters
per second (around 351,000 miles per hour). So an heavy
elephant moving along at a trot would have the same momentum
as small golf ball going very, very fast.
a couple of additional considerations. This is the formula
for momentum under classical (Newtonian physics). The formala
under relativistic physics is slightly different and allows
for objects like photons, which have no mass, to still have
momentum. Also a complete description of momentum for an
object includes the direction (or vector) of the motion.
Radio Waves Discovered - On May 4th, 1933, Karl Janksy
reported the discovery of radio waves from the center of
our galaxy. They came from an unchanging direction in space
which turned out to be center of the Milky Way. Janksy conducted
his research using the radio equipment at Bell Telephone
Labs in Holmdel, N.J.
Sky for Eta Aquarids Shower - May 6th though the 7th
brings us peak of the Eta Aquarids Meteor Shower. This shower
can produce up to 60 meteors per hour at its peak in the
Southern Hemisphere. Viewers in the Northern Hemisphere
can expect half on that. The shower runs annually from April
19 to May 28 and will radiate from the constellation Aquarius.
Dark skies will ensure good viewing this year.
Chickenosaurus a Step Closer - According to a study
outlined in the journal Evolution, scientists are one step
closer to creating "Dino-Chicken." In the experiment scientists
from University of Chile's Department of Biology inhibited
a single bird bone maturation gene, called Indian Hedgehog
(IHH), to modify an embryo chick's leg to be similar to
a dinosaurs. In dinosaurs the fibula bone is tube shaped
and reaches all the way down to the ankle. In chickens,
however, the fibula no longer connects to the ankle. This
is just another of several experiments where scientists
have been able to revert chicken characteristics to that
of dinosaurs (others included changes to the toes and snout).
Though none of these experiments have resulted in a live
chicken Paleontologist Jack Horner would like to make a
"Chickenosaurus" created by reverting all a chicken's genes
to their dinosaur counterparts.
and Meep are on a well deserved vacation. In their place
we feature highlights from their past adventures.