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Ron
Clarke busy excavating the Little Foot Skull from
the Sterkfontein Caves. (Credit
Wits University)
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Science
Over the Edge
A
Roundup of Strange Science for the Month
January/Feburary
2018
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In the
News:
Ancient
"Little Foot" Revealed -
South Africa's status as a major cradle in the African nursery
of humankind has been reinforced with today's unveiling
of "Little Foot", the country's oldest, virtually complete
fossil human ancestor. Little Foot is the only known virtually
complete Australopithecus fossil discovered to date. It
is by far the most complete skeleton of a human ancestor
older than 1.5 million years ever found. It is also the
oldest fossil hominid in southern Africa, dating back 3.67
million years. The unveiling was the first time that the
completely cleaned and reconstructed skeleton can be viewed
by the national and international media. Discovered by Professor
Ron Clarke from the Evolutionary Studies Institute at the
University of the Witwatersrand in Johannesburg, South Africa,
the fossil was given the nickname of "Little Foot" by Prof.
Phillip Tobias, based on Clarke's initial discovery of four
small footbones. Its discovery is expected to add a wealth
of knowledge about the appearance, full skeletal anatomy,
limb lengths and locomotor abilities of one of the species
of our early ancestral relatives. "This is one of the most
remarkable fossil discoveries made in the history of human
origins research and it is a privilege to unveil a finding
of this importance today," says Clarke.
Reptile
Heads Back to the Sea - Using modern research tools
on a 155-million-year-old reptile fossil, scientists at
Johns Hopkins and the American Museum of Natural History
report they have filled in some important clues to the evolution
of animals that once roamed land and transitioned to life
in the water. A report on the new discoveries about the
reptile, Vadasaurus herzogi, suggests that some of the foot-long
animal's features, including its elongated, whip-like tail,
and triangular-shaped head, are well suited to aquatic life,
while its relatively large limbs link it to land-loving
species. The well-preserved fossil is housed in the American
Museum of Natural History in New York, where the job of
unlocking its evolutionary secrets fell to museum research
associate Gabriel Bever, Ph.D., who is also assistant professor
of functional anatomy and evolution at the Johns Hopkins
University School of Medicine, and Mark Norell, Ph.D., the
museum's paleontology division chair. According to Bever,
their work adds to the list of sea creatures whose ancestors
were land-dwelling vertebrates. They include modern-day
whales, seals, and sea snakes, and ancient (and now-extinct)
species of ichthyosaurs, mosasaur, and plesiosaurs. Bever
speculates that Vadasaurus did not use its limbs for propulsion
in the water, but to steer. He says Vadasaurus may have
swum like a modern sea snake, moving its spinal column with
an undulating kind of motion."Our data indicate that Vadasaurus
is an early cousin of the pleurosaur," says Bever. "And
these two reptiles are closely related to modern tuatara."
The modern tuatara is a lizard-like, land-dwelling reptile
that lives on New Zealand's coastal islands and is the single
remaining species of rhynchocephalian still left on Earth.
Comet
is Weird - When comet 45P zipped past Earth early in
2017, researchers observing from NASA's Infrared Telescope
Facility, or IRTF, in Hawai'i gave the long-time trekker
a thorough astronomical checkup. The results help fill in
crucial details about ices in Jupiter-family comets and
reveal that quirky 45P doesn't quite match any comet studied
so far. Like a doctor recording vital signs, the team measured
the levels of nine gases released from the icy nucleus into
the comet's thin atmosphere, or coma. Several of these gases
supply building blocks for amino acids, sugars and other
biologically relevant molecules. Of particular interest
were carbon monoxide and methane, which are so hard to detect
in Jupiter-family comets that they've only been studied
a few times before. The results reveal that 45P is running
so low on frozen carbon monoxide, that it is officially
considered depleted. By itself, this wouldn't be too surprising,
because carbon monoxide escapes into space easily when the
Sun warms a comet. But methane is almost as likely to escape,
so an object lacking carbon monoxide should have little
methane. 45P, however, is rich in methane and is one of
the rare comets that contains more methane than carbon monoxide
ice. "Comet scientists are like archaeologists, studying
old samples to understand the past," said Boncho Bonev,
an astronomer at American University and the second author
on the paper. "We want to distinguish comets as they formed
from the processing they might have experienced, like separating
historical relics from later contamination."
Rock
Hats Tell New Easter Island Story - Analysis of giant
stone hats found on Rapa Nui, Chile (Easter Island) provides
evidence contrary to the widely held belief that the ancient
civilization had a warrior culture. According to a new study
conducted by a team of researchers, these stone hats suggest
that the people of Rapa Nui were part of a supportive and
inclusive community. Carl Lipo, anthropology professor and
director of the Environmental Studies Program at Binghamton
University, and a team of researchers studied the monumental
statues (moai) on Rapa Nui, and the previously unacknowledged
giant stone hats (pukao) that were placed atop them. Using
photography to produce 3D computer models, the researchers
were able to study the pukao in greater detail and discovered
that there are far more drawings carved into the hats than
was previously thought. "With the building mitigating any
sense of conflict, the moai construction and pukao placement
were key parts to the success of the island," said Lipo.
"In our analysis of the archaeological records, we see evidence
that demonstrates the prehistoric communities repeatedly
worked together to build monuments. The action of cooperation
had a benefit to the community by enabling sharing of information
and resources." While Easter Island is famous, the archaeological
record of the island is not well-documented, said Lipo.
He believes that scientists can learn a great deal from
the pukao by examining this new information.
Star
is Eating Its Own Planets - A team of U.S. astronomers
including UCLA's Benjamin Zuckerman has found evidence suggesting
that the strange, unpredictable dimming of a star 550 light-years
away may be caused by vast orbiting clouds of gas and dust.The
star, RZ Piscium, is in the constellation Pisces, and the
huge dust clouds appear to be the remains of one or more
destroyed planets. During the erratic dimming episodes,
which can last as long as two days, the star becomes as
much as one-tenth as bright. A paper detailing the findings
is published today in the Astronomical Journal. The star
is young -- between 30 million and 50 million years old,
the astronomers estimate. But typically, the dust from the
star's youth would have dispersed after a few million years,
so scientists did not expect that a star that "old" would
be surrounded by so much gas and dust. "I've been studying
young stars near Earth for 20 years and I've never seen
anything like this one," said Zuckerman, a professor of
astronomy. "Most sun-like stars have lost their planet-forming
disks within a few million years of their birth. The fact
that RZ Piscium hosts so much gas and dust after tens of
millions of years means it's probably destroying, rather
than building, planets." Kristina Punzi, a doctoral student
at the Rochester Institute of Technology and the study's
lead author, added "Our observations show there are massive
blobs of dust and gas that occasionally block the star's
light and are probably spiraling into it."
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Science
Quote of the Month - “Science
is a beautiful gift to humanity; we should not distort it."
- A. P. J. Abdul Kalam
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What's
New at the Museum:
Seven
Wonder of the Age of Steam: We selected seven wonders
from the 19th century that represent the most amazing achievements
of the age of steam: -
Full
Story
Mysterious
Picture of the Month - What
is this?
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Ask
the Curator:
VASIMR
Engine - I was reading about the VASIMR engine
that Franklin Chang Diaz is building and I read it has an
ISP of 4000-5000 while a falcon 9 rocket built by SpaceX
has an ISP of only 300 and some. My question is what ISP
would a plasma ion engine need to lift off from the surface
of earth and make it to space. I don't have any ideas on
what the weight would be of the ship. Sorry if this is a
silly question. It's just in films like the chronicles of
Riddick one of the Furyans say they've "located an ion trail
that goes offworld." - C. Bell.
The ISP (Specific Impulse) of a rocket engine is a measure
of the weight of the propellant used to get a certain amount
of thrust. It can give you an idea how efficiently the engine
uses it's propellant, but it does not take into account
the mass of the spacecraft itself which would be a critical
concern for lifting off from a high gravity object, like
the Earth.
The
VASIMR can create a very high ISP by sending ions and electrons
out its exhaust at somewhere around 50,000 meters/second.
To do this it takes a propellant material (perhaps hydrogen,
since it the most abundant material in the universe) and
uses radio waves to ionize it (heat it till the electrons
separate from the nucleus of the hydrogen atoms) then uses
a powerful magnetic field to accelerate the ionized propellant
out the exhaust to create thrust. The problem is that the
electric power needed to heat the propellant and create
those magnetic fields can be significant. To send a manned
ship to Mars you would probably need a small but powerful
nuclear reactor on it.
There are several problems with the idea of launching a
rocket powered by a nuclear reactor from Earth. The first
is that the reactor would likely be so heavy that any the
advantage of the VASIMR's high thrust would be negated by
the weight of the rocket. There are also serious concerns
about the environmental impact of the reactor's nuclear
fuel scattering over a wide area should there be an accident
during the launch.
That
doesn't mean that VASIMR, and similar electromagnetic thruster
based engine schemes, do not have a future in spaceflight.
Carrying a heavy power reactor on your spaceship may not
be such a big deal if your ship is leaving from a space
station in orbit, rather than launching from Earth. It's
not hard to envision a day where passengers and cargo ride
up to an orbital platform on conventional rockets, or via
a space elevator, then ride to Mars on a VASIMR powered
interplanetary shuttle. By leaving from a space station
in orbit, the size and weight of the vessel are a much smaller
issue.
For example, NASA's Deep Space 1 probe used an NSTAR ion
engine (another type of electromagnetic thruster) to carry
it out to survey the asteroid 9969 Braille back in 1999.
This worked because the probe was launched from Earth with
a conventional rocket. Once it had gotten away from Earth
and shed the booster that go it into orbit, it was very
light and was able to power its engine via solar panels
on the craft.
These
type of drives look like they are excellent candidates for
space probes moving between planets, but unless a very compact
power plant is invented, they may be impractical for launching
from the surface of a large celestial body into space.
Have
a question? Click here to
send it to us.
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In
History:
First
Public View of the Telegraph -On January 6th, in 1838,
Samuel Morse, with his partner, Alfred Vail, gave the first
public demonstration of their new invention electric telegraphic
system at the Speedwell Iron Works in Morristown, N.J.
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In
the Sky:
Total Lunar Eclipse - On January 31st a total Lunar
Eclipse will be visible throughout most of western North
America, eastern Asia, Australia, and the Pacific Ocean
. A total eclipse occurs when the Moon passes through the
Earth's shadow. During the eclipse, the Moon will slowly
get darker and then take on a blood red color.
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Observed:
Secret UFO Government Investigation Comes to Light - In
December the realization that the Air Force had a secret
program from 2007 to 2012 studying UFOS came to light. One
of the most intriguing incidents studied occurred in 2004
off the cost of California when the Air Force tracked an
oblong shaped flying object without wings. Former U.S Navy
pilot, Cmdr. David Fravor, whose F/A-18 Hornet fighter jet
tracked the object, stated is looked like "A White Tic-Tac,
about the same size as a Hornet, 40-feet long with no wings,"
adding that it was "Just hanging close to the water." Other
jets recorded video of the object and Favor was sure it
was no optical illusion. "It was a real object, it exists
and I saw it," later adding that it was "Something not from
the Earth." Despite being studied as a part of the Air Force
project, no conclusions were reached about what the pilots
saw that day.
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LGM:
Zeep
and Meep are on a well deserved vacation. In their place
we feature highlights from their past adventures.
LGM
Archive 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
2008, 2009,
2010, 2011,
2012,
2013,
2014
Copyright Lee Krystek 2018. All Rights Reserved.
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