Jean E. Lane's Imagine This: ALMA: InSearch of Cosmic Knowledge
ALMA, short fo...: ALMA: In Search of Cosmic Knowledge ALMA, short for “Atacama Large Millimeter Array,” is the largest observatory ever built. The ob...
A "kid friendly" blog chock full of facts, science, and adventure. Exploring the literary world along with writing tips, skygazing, focusing on Mars and outerspace. Who knows what the future will bring with this blog...hence the name, Jean E. Lane's Imagine This
Friday, January 22, 2016
ALMA: In
Search of Cosmic Knowledge
ALMA, short for “Atacama Large Millimeter Array,” is
the largest observatory ever built. The observatory is located at an altitude
of 3.1 miles high on the Chajnantor plateau in the Chilean desert near San
Pedro De Atacama, in a place so dry and red it appears that it could be Mars.
Dozens of antennas stare at the sky in unison. There is an array of 66 radio
telescopes with a diameter of 39 feet and 23 feet observing the sky at
millimeter and sub-millimeter wavelengths. They can see deeper and farther in
this light than any telescope before. ALMA’s purpose is to provide insight on
the birth of stars as well as detailed imaging of local star and planet
formation.
As you might expect, a project like this was an
international partnership between Europe, the United States, Canada, several
countries from East Asia and the Republic of Chile. With 30 years of planning
and 10 years of construction the entire project took thousands of scientists
and engineers from around the world to complete. The total price tag was
approximately $1.3 billion dollars and was split by the three sponsoring
regions. Of the total cost the United States taxpayers contributed about $500
million.
The Llano de Chajnantor Observatory in Chile has
been fully operational since March of 2013. ALMA combines dozens of these individual
radio telescope dishes into a single observing instrument. What is amazing to
me is that the resolution will be five times greater than that of the Hubble
Space Telescope.
Some facts about ALMA that intrigued me:
·
The observatory is accurate enough to
detect a golf ball nine miles away.
·
This high altitude is one of the driest
places on Earth. This means no clouds.
·
The dish design is almost perfect which
prevent any loss of incoming radio waves.
·
Each ALMA antenna must be kept at a
chilling -452 degrees Fahrenheit to prevent noise.
·
This will allow astronomers to see into distant
gas clouds to study star and planet formation.
ALMA means “soul” in Spanish and “learned” or
“knowledgeable” in Arabic. It will be interesting to see what information we
can learn from our collective efforts in our search for knowledge about our
universe. I find it a bit ironic that ALMA, in her otherworldly setting,
sitting high atop a snow-capped plateau, surrounded by volcanoes, is also
stepping up the search for alien life…somewhere…out there.
My sources: Alma Observatory, Space.com, The
Telegraph UK, www.phys.org,
www.eso.org,
, The Planetary Society, and en.wikipedia.org.
Tuesday, November 24, 2015
Quintenary
Star System: Anything But Ordinary
We’ve all heard about binary stars (one star
revolving around another). The most popular binary stars are Mizar and its
fainter companion star Alcor. To find them, look for the Big Dipper and find
the handle; you’ll spot Mizar first as the middle star of the Big Dipper’s
handle. Look closely and you’ll see Alcor right next to Mizar.
Harder to find are the trinary star systems, or
triple star systems. It’s interesting to me because usually two of the stars form
a close binary system while the third star orbits this pair at a distance in a
much larger orbit. One such system is the Alpha Centauri star system with
Proxima Centauri at a distance of 4.22 light years. It is the closest star to
Earth beyond our own Sun.
The Kepler Space Telescope observed KIC 2856960 for
four straight years before astronomers seemed to have enough data to make a
determination. But when three astronomers, Marsh, Armstrong, and Carter in the
UK started digging into the numbers, they discovered the system was anything
but ordinary. First they observed two stars in close orbit of one another: a
binary system. The smaller star seemed to orbit the larger one every 6 hours.
However, there appeared to be a third star that entered into the equation every
204 days. This was throwing off their results. As they diligently worked out
their dilemma on paper, other astronomers became involved. It’s the fact that
they could not find a precise set of masses and radii for the component stars.
We can’t explain why this star system is producing an ‘impossible’ light curve.
As the team studied the data from KIC 2856960 they
saw a small dip in brightness about 4 times a day and a larger dip every 204
days. Okay, not a big deal; it’s a triple star system, so let’s move on to other
data. But they were drawn back to their results to look at it with even more
detail. After all, this was tricky, and there were all sorts of things that threw
off results, such as starspots and other stellar activity. The more they looked
at the data, the more confusing things got. At first glance, it looked like a
triple star system, but the stars’ orbits didn’t seem to fit. They kind of fit,
but there were fluctuations in the data. So the team tried another scenario and
found that a four-star system worked—a quintenary system—two sets of binary
stars!
This is anything but ordinary, and further data
needs to be collected, but it’s clear that this is not a simple, boring triple-star system. We just don’t understand it yet. Perhaps the
Transiting Exoplanet Survey Satellite, or TESS, will be able to shed some light
on this. TESS is scheduled to launch in 2017. Until then KIC 2856960 is likely
to remain a mystery. Is this a quintenary star system? Is there a planet hidden
in this system? Don’t you love a good mystery?
My sources: AtlasoftheUniverse.com, space.com,
phys.org, pbs.org, atrobites.org, astronomy.com, and American Association of
Variable Star Observers (AAVSO)
Sunday, September 6, 2015
Mordor
Macula, Vader Crater, Nostromo Chasma…
By Jean E. Lane
New
Horizons’ flyby of Pluto and Charon, its largest moon
provided us with many incredible images. But the highly detailed images gave
the New Horizons team an
unanticipated problem: What do they call all those mountain ranges, plains, and
craters?
What happens next is that the team intends to submit
them to the International Astronomical Union (IAU), who is the official
governing body for names of celestial objects. Here’s what’s currently being
proposed to the committee; how about choosing names from Star Trek, Star Wars, Doctor Who, Firefly, Alien, and Lord of the Rings? The New Horizons team actually asked for submissions
from the public, and they were only too happy to oblige.
Since Pluto was named after a god of the underworld,
the names must be drawn from underworld mythology. NASA offered the Cthulu
regio (a large region with color variances). Also chosen was the name Balrog macula
(meaning dark spot) which honored Lovercraft’s dark god and the underground
demons from stories by J.R.R. Tolkein.
All that’s wonderful news, but it’s Charon, Pluto’s
moon, and the IAU rules permit names that reference “destinations and
milestones of fictional space” as well as fictional spaceships and travelers.
This notion grabbed the imaginations of many space fans, and their thoughts
went directly to the iconic science fiction shows and movies that they revere.
Thus, the suggestions were presented, and the
unofficial names, of craters are Vader, Skywalker and Leia Organa. For the plains
they propose names of Spock, Kirk, Sulu, and Uhura, which would dot the Vulcan
Planum. How about the Tardis chasma that crosses the Gallifrey macula? This name, of course is in reference to The Doctor’s
(Doctor Who) vessel and planet. It
also has been proposed that names from Alien,
such as Ripley crater and Nostromo chasma, would be excellent choices. The name
Serenity chasma in respect for Firefly
also has a chance to become a real place on Charon. There’s room for one from Lord of the Rings, the giant Mordor
macula at Charon’s North Pole.
Although they are nevertheless provisional, “We
still have a decent chance of getting these names approved,” stated New Horizons planetary scientist Mark
Showalter. After all, the IAU has
previously approved features on Saturn’s moon, Titan, named Frodo and Bilbo,
and the first landing site on Mars is now called Bradbury’s Landing!
Ah, this is news that stirs the creative abyss of a
science fiction or science “faction” heart!
References: NASA, The Planetary Society,
Mashable.com, International Astronomical Union, EarthSky, Washington Post, and
National Geographic
Saturday, August 1, 2015
GLOBULAR
CLUSTERS…What are they?
You may have heard the term “Globular Clusters”
before, but exactly what are they? According
to the Planetary Society: “Like stellar time capsules adorning the periphery of
galaxies, globular clusters contain some of the oldest stars in the universe.”
Some of these star clusters may seem to have the appearance of galaxies. This
is because they are a symmetrical system of stars with the highest
concentration of stars near their own center and bound together by gravity.
Imagine yourself on a world where the sky is always ablaze with the sight of
hundreds of thousands of stars as bright as the full Moon. Most likely these
stars would be the older, fainter, red and yellow stars.
The more dense globular clusters can be found in the
halo of a galaxy, whereas the less dense galactic, or open, clusters are
located in the disk of a galaxy. The clusters in the halo contain considerably
more stars than the open clusters. Globular clusters are fairly common; there
are about 157 of them currently known in the Milky Way Galaxy. Larger galaxies,
such as our neighbor Andromeda, may have as many as 500. Moreover, the giant
elliptical galaxies may have as many as 13,000 globular clusters. The first globular cluster discovered was M22 in 1665 by Abraham Ihle, a German amateur astronomer. However, given the poor aperture ability of early telescopes, individual stars within a globular cluster were not resolved until Charles Messier observed M4, discovered in 1746. The designation before a number refers to the catalog where the discovery is listed. The letter “M” tells us it is listed in the Messier catalog, whereas “NGC” tell us it could be found in the New General Catalog by John Dreyer. The designation letter is something that I’ve wondered about and just learned more details in this research.
We have 157
cataloged globular clusters right in our own galactic neighborhood, the Milky Way. There are too many to list here, but our largest cluster is Omega Centauri (NGC5139) and second is 47 Tucanae, both of which can be observed with the naked eye under the right conditions., M4 and NGC6397 are both 7200 light years away. Some other noteworthy clusters are NCG104, NGC4833, M55, M69, and M13. There are so many of these beautiful star clusters - out there, waiting for you to discover.
My
sources: NASA.gov, en.wikipedia.org, spider.seds.org, astrosociety.org,
hyperphysicis.phy-astr.gsu.edu, astro.keele.ac.uk, Britannica.com, The
Planetary Society, ned.ipac,caltech.edu, and astronomy.com.
Saturday, May 2, 2015
Does a Real-Life Death Star Exist?
Does
a Real-Life Death Star Exist?
No, I’m not talking about something from the movies.
That star would need to get close to a planet to destroy it. WR104, however,
has the potential to burn worlds from thousands of light years away. This is Wolf-Rayet
104 located in the constellation of Sagittarius about 2,222 parsecs away. Okay,
that’s about 8,000 light-years from us which may seem like a safe distance, but
consider that WR104 is 25 times the size of our sun, very dense, and much, much
hotter. Add to that mix the fact that this star is rotating rapidly and
expelling its gases creating a spiral around it; it is dying.
At this level of brightness the radiation field
around the star takes on a life of its own and plays a most unusual role; it
sheds off the outer atmosphere of the star by photon pressure. Therefore,
Wolf-Rayet stars are so luminous that they are literally flying apart! This
creates a high-velocity stellar wind surrounding the star which first grabbed
the attention of astronomers. Wolf-Rayet stars are very rare, only 230 have
been discovered, so far, in our Milky Way Galaxy. Of these stars, half of them
have a binary companion star which burns just as hot as the main star.
First discovered in 1998 by the Keck 1 Telescope,
this star was photographed, studied, measured, and cataloged. Scientists were
first taken by the size and beauty of this spiral image. They determined the
diameter to be 160AU (Astronomical Units), which is 160 times the distance from
Earth to the sun. Peter Tuthill, at the University of Sydney in Australia, has
been studying WR104 for years. He realized it rotated in a circle every eight
months and found one devastating fact: Earth looks down the axis of the system.
We are not looking at it from an angle, but dead-on, like looking down the
barrel of a rifle.
Another fact which concerns astronomers is that
WR104 is not a single star system, rather a binary system. It has another Class
OB star locked in orbit with it. As they circle one another, plumes of
streaming gas are driven from their surfaces creating a fiery, colorful
pinwheel in space. Astronomers fear the fuse for this star is very short; it
may explode within the next few hundred thousand years. When it does it may
emit an intense beam or ‘gamma ray burst.’ It is impossible to predict whether
or not it will actually create the dreaded gamma ray beam directed at Earth;
the exact outcome is still unknown. Some reports say, “Not to worry,” others
say, “Earth is in line with a death-star.”
I say, it’s a long time away; we have more important things to worry
about until then.
My Sources: Astro Dept. at University of Michigan,
nature.com/news, dailygalaxy.com, popsci.com, science.time.com,
universetoday.com, space.com, and en.wikipedia.org
Saturday, March 14, 2015
Planet
Hunter: TESS
Transiting Exoplanet Survey Satellite (TESS) will be
launched in 2017 as an Astrophysics Explorer mission. This satellite will be an
Explorer class planet finder. As the first ever spaceborne all-sky transit
survey, TESS will identify planets ranging from Earth-sized to gas giants that
orbit around their bright host star in the solar neighborhood. The mission goal
is to find detailed characterizations of these planets and determine their
atmospheres.
NASA will launch TESS from Cape Canaveral, Florida
in August of 2017 on a SpaceX Falcon 9 rocket and will achieve a unique high
altitude orbit according to the mission’s top scientist, George Ricker. The
satellite will carry four wide field-of-view 16.8 megapixel cameras to cover
400 times the area of the sky seen by Kepler. In its two year mission TESS will
be circle nearby stars and look for planets. Part of the mission is a follow up
of observations from Earth to determine whether the alien worlds might be
suitable for life.
TESS is expected to monitor more than 500,000 stars
during its mission, searching for temporary fluctuations in brightness caused
by planetary transits. Transits occur when a planet’s orbit carries it directly
in front of its host star as viewed from Earth. It should be able to catalog
more than 3,000 transiting exoplanet candidates. This would include 500
Earth-sized and super-Earth sized planets as well as smaller rocky ice planets
in the ‘goldilocks’ or habitable zone. It is hoped that these observations will
refine the measurements of the planet masses, sizes, densities, and atmospheric
properties.
This will be the first ever spaceborne all-sky
transit survey which means that the search for exoplanets is heating up, and it
appears that Earth’s scientists have no intention of slowing down. Our sun is a
Class G star – or a yellow-white main sequence star. TESS will be able to detect
the variances in a star’s brightness and will be looking for Class M stars (or
suns) that are a bit cooler than our own sun. Class M stars are reddish stars 2
to 3 times more abundant as solar type stars. How many of these suns will we
actually find? What are the chances of finding another planet similar to Earth?
What are the odds of finding a planet that supports any type of life? I, for
one, am very curious to see what is out there. Aren’t you?
My sources: NASA.gov, tess.gfc.nasa.gov,
en.wikipedia.org, space.mit.edu, spaceflightnow.com, www.kavlifoundation.org,
www.universetoday.com,
and www.stsci,edu
.
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