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A candidate planet outside our solar system was validated
using data from the Habitable-zone Planet Finder Spectrograph,
a Penn State-led near-infrared spectrograph recently
installed on the 10m Hobby-Eberly Telescope at McDonald
Observatory in Texas CREDIT Ethan
Tweedie Photography
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Science
Over the Edge
A
Roundup of Strange Science for the Month
March/April
2020
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In the
News:
Astronomers Find Possible Habitable Planet -A signal
originally detected by the Kepler spacecraft has been validated
as an exoplanet using the Habitable-zone Planet Finder (HPF),
an astronomical spectrograph built by a Penn State team
and recently installed on the 10m Hobby-Eberly Telescope
at McDonald Observatory in Texas. The HPF provides the highest
precision measurements to date of infrared signals from
nearby low-mass stars, and astronomers used it to validate
the candidate planet by excluding all possibilities of contaminating
signals to very high level of probability. The details of
the findings appear in the Astronomical Journal. The planet,
called G 9-40b, is about twice the size of the Earth, but
likely closer in size to Neptune, and orbits its low mass
host star, an M dwarf star, only 100 light years from Earth.
Kepler detected the planet by observing a dip in the host
star's light as the planet crossed in front of--or transited--the
star during its orbit, a trip completed every six Earth
days. This signal was then validated using precision spectroscopic
observations from the HPF, ruling out the possibility of
a close stellar or substellar binary companion. Observations
from other telescopes, including the 3.5m telescope at Apache
Point Observatory and the 3m Shane Telescope at Lick Observatory,
helped to confirm the identification. "G 9-40b is amongst
the top twenty closest transiting planets known, which makes
this discovery really exciting," said Guðmundur Stefánsson,
lead author of the paper, and a former PhD student at Penn
State who is currently a postdoctoral fellow at Princeton
University. "Further, due to its large transit depth, G
9-40b is an excellent candidate exoplanet to study its atmospheric
composition with future space telescopes." "The spectroscopic
observations from HPF allowed us to place an upper bound
of 12 Earth masses on the mass of the planet," said Caleb
Cañas, a graduate student at Penn State and an author of
the paper. "This demonstrates that a planet is causing the
dips in light from the host star, rather than another astrophysical
object such as a background star. We hope to obtain more
observations with HPF to precisely measure its mass, which
will allow us to constrain its bulk composition and differentiate
between a predominantly rocky or gas-rich composition."
"It is exciting to see this first result of the HPF survey
coming out. HPF was built from the ground up to enable precision
measurements to discover and confirm planets," said Larry
Ramsey, emeritus professor of astronomy and astrophysics
at Penn State.
Archaeologists
Receive Letter From Biblical Era - "And the Lord delivered
Lachish into the hand of Israel, which took it on the second
day, and smote it with the edge of the sword, and all the
souls therein..." -Joshua, 10:32 The Biblical Book of Joshua
tells the story of the ancient Israelites' entry into the
Promised Land after a 40-year sojourn in the desert. Now,
a team of archaeologists led by Professor Yosef Garfinkel
at the Hebrew University of Jerusalem's Institute of Archaeology
and Professor Michael Hasel at Southern Adventist University
in Tennessee, have opened a window onto the Canaanite society
that inhabited the land during that era. In a study published
last month in Levant, Garfinkel and his co-authors revealed,
for the first time ever, extensive ruins of a Canaanite
temple dating to the 12th century BCE that they uncovered
in National Park Tel Lachish, a large Bronze Age-era settlement
near the present-day Israeli city of Kiryat Gat. Lachish
was one of the most important Canaanite cities in the Land
of Israel during the Middle and late Bronze Ages; its people
controlled large parts of the Judean lowlands. The city
was built around 1800 BCE and later destroyed by the Egyptians
around 1550 BCE. It was rebuilt and destroyed twice more,
succumbing for good around 1150 BCE. The settlement is mentioned
in both the Bible and in various Egyptian sources and was
one of the few Canaanite cities to survive into the 12th
century BCE. "This excavation has been breath-taking," shared
Garfinkel. "Only once every 30 or 40 years do we get the
chance to excavate a Canaanite temple in Israel. What we
found sheds new light on ancient life in the region. It
would be hard to overstate the importance of these findings."
The layout of the temple is similar to other Canaanite temples
in northern Israel, among them Nablus, Megiddo and Hazor.
The front of the compound is marked by two columns and two
towers leading to a large hall. The inner sanctum has four
supporting columns and several unhewn "standing stones"
that may have served as representations of temple gods.
The Lachish temple is more square in shape and has several
side rooms, typical of later temples including Solomon's
Temple. Only time will tell what treasures still remain
to be uncovered in the ancient city of Lachish.
The
Earth Formed Much Faster Than Previously Thought - The
precursor of our planet, the proto-Earth, formed within
a time span of approximately five million years, shows a
new study from the Centre for Star and Planet Formation
(StarPlan) at the Globe Institute at the University of Copenhagen.
On an astronomical scale, this is extremely fast, the researchers
explain. If you compare the solar system's estimated 4.6
billion years of existence with a 24-hour period, the new
results indicate that the proto-Earth formed in what corresponds
to about a minute and a half. Thus, the results from StarPlan
break with the traditional theory that the proto-Earth formed
by random collisions between larger and larger planetary
bodies throughout several tens of millions of years - equivalent
to about 5-15 minutes out of the above-mentioned fictional
24 hours of formation. Instead, the new results support
a more recent, alternative theory about the formation of
planets through the accretion of cosmic dust. The study's
lead author, Associate Professor Martin Schiller, explains
it as follows: 'The other idea is that we start from dust,
essentially. Millimetre-sized objects, all coming together,
raining down on the growing body and making the planet in
one go,' he says, adding: 'Not only is this implication
of the rapid formation of the Earth interesting for our
solar system. It is also interesting to assess how likely
it is for planets to form somewhere else in the galaxy.'
18-Hour
Year Planet On Edge Of Destruction - Astronomers from
the University of Warwick have observed an exoplanet orbiting
a star in just over 18 hours, the shortest orbital period
ever observed for a planet of its type. It means that a
single year for this hot Jupiter - a gas giant similar in
size and composition to Jupiter in our own solar system
- passes in less than a day of Earth time. The planet NGTS-10b
was discovered around 1000 light years away from Earth as
part of the Next-Generation Transit Survey (NGTS), an exoplanet
survey based in Chile that aims to discover planets down
to the size of Neptune using the transit method. This involves
observing stars for a telltale dip in brightness that indicates
that a planet has passed in front of it. Lead author Dr
James McCormac from the University of Warwick Department
of Physics said: "We're excited to announce the discovery
of NGTS-10b, an extremely short period Jupiter-sized planet
orbiting a star not too dissimilar from our Sun. We are
also pleased that NGTS continues to push the boundaries
in ground-based transiting exoplanet science through the
discovery of rare classes of exoplanets. "Although in theory
hot Jupiters with short orbital periods (less than 24 hours)
are the easiest to detect due to their large size and frequent
transits, they have proven to be extremely rare. Of the
hundreds of hot Jupiters currently known there are only
seven that have an orbital period of less than one day."
Massive planets typically form far away from the star and
then migrate either through interactions with the disc while
the planet is still forming, or from interactions with additional
planets much further out later in their life. The astronomers
plan to apply for time to get high-precision measurements
of NGTS-10b, and to continue observing it over the next
decade to determine whether this planet will remain in this
orbit for some time to come - or will spiral into the star
to its death.
Brain
Cells Protect Muscles From Wasting Away - While
many of us worry about proteins aggregating in our brains
as we age and potentially causing Alzheimer's disease or
other types of neurodegeneration, we may not realize that
some of the same proteins are aggregating in our muscles,
setting us up for muscle atrophy in old age. University
of California, Berkeley, scientists have now found brain
cells that help clean up these tangles and prolong life
-- at least in worms (Caenorhabditis elegans) and possibly
mice. This could lead to drugs that improve muscle health
or extend a healthy human lifespan. The research team's
most recent discovery, published Jan. 24 in the journal
Science, is that a mere four glial cells in the worm's brain
control the stress response in cells throughout its body
and increase the worm's lifespan by 75%. That was a surprise,
since glial cells are often dismissed as mere support cells
for the neurons that do the brain's real work, like learning
and memory. This finding follows a 2013 study in which the
UC Berkeley group reported that neurons help regulate the
stress response in peripheral cells, though in a different
way than glial cells, and lengthen a worm's life by about
25%. In mice, boosting neuronal regulation increases lifespan
by about 10%. Together, these results paint a picture of
the brain's two-pronged approach to keeping the body's cells
healthy. When the brain senses a stressful environment --
invading bacteria or viruses, for example -- a subset of
neurons sends electrical signals to peripheral cells to
get them mobilized to respond to the stress, such as through
breaking up tangles, boosting protein production and mobilizing
stored fat. But because electrical signals produce only
a short-lived response, the glial cells kick in to send
out a long-lasting hormone, so far unidentified, that maintains
a long-term, anti-stress response. "We have been discovering
that if we turn on these responses in the brain, they communicate
to the periphery to protect the whole organism from the
age onset decline that naturally happens. It rewires their
metabolism, it also protects against protein aggregation,"
said Andrew Dillin, UC Berkeley professor of molecular and
cell biology and Howard Hughes Medical Institute (HHMI)
investigator. As a result of the new study, "We think that
glia are going to be more important than neurons." While
the roundworm C. elegans is a long way evolutionarily from
humans, the fact that glial cells seem to have a similar
effect in mice suggests that the same may be true of humans.
If so, it may lead to drugs that combat muscle wasting and
obesity and perhaps increase a healthy lifespan. "If you
look at humans with sarcopenia or at older mice and humans,
they have protein aggregates in their muscle," Dillin said.
"If we can find this hormone, perhaps it can keep muscle
mass higher in older people. There is a huge opportunity
here."
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Science
Quote of the Month - "IIf
you believe in science, like I do, you believe that there
are certain laws that are always obeyed." - Stephen
Hawking
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What's
New at the Museum:
Big
Snakes - What's the biggest snake in the world? People
have argued about this for years. Part of the problem is
the definition of the word "large." Do you mean the longest
or the heaviest? Are we talking about the largest single
specimen ever found or an average for the species? Do you
consider unconfirmed reports, or only rely on double-checked
evidence? >Full Story
Mysterious
Picture of the Month - What
is this?
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Ask
the Curator:
DNA
vs GENES - I would like to know the difference
between DNA and genes. - Kamini
DNA
stands for deoxyribonucleic acid. It is a double-stranded,
helical nucleic acid molecule that encodes information
hereditary information for almost all living organisms.
A gene is one section of the DNA that controls
a specific function or characteristic.
DNA is arranged like a twisted ladder with the up
and down rails composed of sugar molecules and phosphate
molecules connected to rungs made of either adenine
and thymine or guanine and cytosine. One section of
rail and a half rung is called a nucleotide
and each nucleotide can be connected with others to
make both sides of the ladder and to make the ladder
longer. Because the half rungs (called bases)
can be either adenine, thymine, guanine or cytosine,
there are four different types of nucleotides. The
order of the nucleotides on the ladder is important
as this is how information is encoded into the DNA.
It is not unlike the zeros and ones that encode information
for computer program.
A
group of consecutive nucleotides on the ladder that
composes the instructions necessary to make one protein
is called a gene. The protein molecule that the gene
makes may control characteristics like a person's
eye color, hair color, etc. On average a gene includes
3000 nucleotides, but for some simple proteins only
a few dozen may be needed. Not all DNA nucleotides
are part of a gene. There are lengthy intergenic regions
in between most genes that either have no function
or a regulatory function the scientists are only yet
beginning to understand.
Humans
are believed to have about 20,000 - 25,000 genes.
More than ninety-nine percent of these genes are shared
by all humans with only less than a percent involved
in giving us all those traits that make use individuals.
(In fact chimps, our closet biological relatives,
have the 96% of the same DNA we do). Human DNA is
also split up into unconnected sections called chromosomes.
Humans have 23 pairs of chromosomes. A child gets
one half of each pair from their mother and the other
half from their father which is why a child might
have their father's wide set eyes, but their mother's
eye color. Chromosome number 23 is known as the sex
chromosome because females carry two X types and males
carry one Y and one X.
The
DNA in a gene is divided up into two components. A
"non-coding" section that simply indicates whether
the gene is "on" or "off" (sometimes referred to the
gene being "expressed" or not) and a "coding" section
which contains the instructions to build the protein.
The DNA does not build the protein itself but transcribes
the information to RNA (Ribonucleic acid) to do the
work. RNA looks and acts a lot like DNA, but is made
up of only one half of the twisted ladder and uses
a few alternate materials. In a few cases gene may
not make a protein at all, but just RNA which is then
used in another part of the protein synthesis operation.
Every
cell in our body carries a copy of our DNA and parts
of that DNA are very specific to each person, which
is why it has become as important as fingerprinting
to establish identity. Just a few cells left behind
at a crime scene through a strand of hair can be enough
to let police positively identify someone as the perpetrator.
DNA can also predict if a person will get certain
disease. For example, Tay-Sachs, which is a fatal
disease often afflicting Eastern European Jews, has
been shown to be the result a mutated and non-functioning
HEXA gene. Other genes may not directly cause a disease,
but increase the likelihood of a person getting ill.
For example, researchers have shown that people with
a nonfunctioning CREB gene are at an increased risk
for anxiety and alcoholism.
The
DNA actually looks like a super-tiny thread and is
impossible to see without the use of an electron microscope.
Typically it is curled up on itself so it can fit
inside a microscopic cell. If you were to uncurl the
DNA in a single cell, however, it would stretch out
to about three feet in length and contain three billion
base pairs.
Have a question?
Click here to send it to us.
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In
History:
Kellogg's New Cornflakes - On March 7th in 1897, Dr.
John Kellogg served the world's first cornflakes to his
patients at a sanitarium in Battle Creek, Mich. These original
cornflakes were unlike the familiar commercial breakfast
cereal we see today. Dr. Kellogg's version was ab unsweetened
addition to the diets of his patients, who suffered from
a variety of sicknesses. Dr. Kellogg believed many illnesses
could be cured by a strict vegetarian diet and exercise.
It was his brother, Will Keith Kellogg, who in 1906, added
sugar to the recipe and began marketing them as a commercial
breakfast food. Dr. Kellogg was angered by this and sued
to keep the Kellogg name off of the product.
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In
the Sky:
The
Lyrid Meteor Shower - The Lyrid meteor shower will be
active from April 16th to April 25th, peaking around April
22nd. The best time to see the meteors will be whenever
the shower's radiant point - in the constellation Hercules
- is above the horizon. The shower is likely produce its
best displays shortly before dawn, when its radiant point
is highest.
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Observed:
Might
the Loch Ness Monster Be A Giant Eel? - According to
researchers from New Zealand , the animals behind reports
of the fabled Loch Ness Monster might well be giant eels.
The scientists have attempted to catalogue all living species
there by checking DNA from loch water samples. As a result
the researchers have eliminated as a possibility many of
large creatures that might have been behind the reports
of a monster. Prof Neil Gemmell, from New Zealand's University
of Otago. remarked: "People love a mystery, we've used science
to add another chapter to Loch Ness' mystique. We can't
find any evidence of a creature that's remotely related
to that in our environmental-DNA sequence data. So, sorry,
I don't think the plesiosaur idea holds up based on the
data that we have obtained." He also said, "There is also
no catfish DNA in Loch Ness based on our sampling. We can't
find any evidence of sturgeon either." His conclusion?
"There is a very significant amount of eel DNA. Eels
are very plentiful in Loch Ness, with eel DNA found at pretty
much every location sampled - there are a lot of them. So
- are they giant eels? Well, our data doesn't reveal their
size, but the sheer quantity of the material says that we
can't discount the possibility that there may be giant eels
in Loch Ness."
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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 2020. All Rights Reserved.
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