APOD 4.8

Io: The Prometheus Plume

This picture is of Jupiter's volcanic moon, Io, taken by the Galileo spacecraft, which orbited Jupiter from 1995 to 2003.  It was taken in 1997 from 600,000 kilometers away, and has since been digitallys sharpened.  Two sulfurous eruptions were captured in this image.  Over Pillan Patera, a volcanic caldera, a florescent blue plume can be seen.  This plume rises about 140 kilometers over the Io's surface.  Another ring shaped plume is visible toward the center of the image.  This is known as the Prometheus plume, after the Greek God who gave mortals fire.  In every image ever taken of this region, the Prometheus plume has been visible. Since our first image was taken in 1979 during the Voyager flybys, we know that this plume has been active for at least 18 years.  In recent years, research has uncovered evidence that there is a magma ocean under Io's surface! With as quickly as technology is progressing, I can only imagine what we will uncover about space in a few years!

Harlow Shapley Biogprahy

HARLOW SHAPLEY

Harlow Shapley was an American astronomer, born on November 2, 1885 in Nashville, Missouri.  In April of 1914, he married Martha Betz, who assisted him in astronomical research.  They has one daughter and four sons.  After making notable progress in astronomy, particularly with the Sun and the Milky Way, Shapley died on October 20, 1972.

Harlow Shapley dropped out of school with only a fifth-grade education.  He was very independent and much preferred studying at home by himself.  He researched and covered crime stories as a newspaper reporter before returning to school.  He completed a six-year high school program in two years and graduated at class valedictorian.  At twenty-two, Shapley enrolled at the University of Missouri.  He was initially disappointed that the opening at the School of Journalism was postponed for a year, so he decided to study the first subject in the course directory.  He rejected archeology because he claimed he could not pronounce it.  Next in line was astronomy.

Shapley became fascinated with astronomy and received a fellowship at Princeton University where his mentor was Henry Norris Russell.  Here, Shapley was important in shifting the field astronomy from the belief that Cepheids were spectroscopic binaries to the idea that they were pulsators.  At Princeton, he was also the first to make the realization of the Milky Way’s incredibly large size and to note that the Sun’s place in the galaxy was in a nondescript location.

Harlow Shapley participated in the “Great Debate” against Heber D. Curtis on April 26, 1920.  This is a famous debate that made an immense impact on the astronomical world.  It is also known as the “Shapley-Curtis Debate.”  Shapley argued that the Sun was not the center of the galaxy, and, as we now know, was correct; however he was incorrect in his belief that globular clusters and spiral nebulae are within the Milky Way. 

Proceeding the debate, Shapley was promoted from working at Mount Wilson Observatory, to director at the Harvard College Observatory.  Here he worked from 1921 to 1952.  He wrote many books on astronomy during his time are Harvard, his most famous being Source Book in Astronomy.  In the 1940’s Shapley made one of his most important contributions to the science world, adding the “S” to UNESCO (United Nations Educational, Scientific and Cultural Organization). 

For all of Harlow Shapley’s great work in astronomy, he was honored several awards.  His most prominent of these were the Henry Draper Medal of the National Academy of Sciences, the Gold Medal of the Royal Astronomical Society, and the Prix Jules Janssen of the French Astronomical Society.  In addition to these honors, Shapley has a crater on the Moon named after him.  There is also an asteroid named “Asteroid 1123 Shapleya” and a starcluster named “Shapley Supercluster.”

It is truly amazing and fortunate for the world of science that this man, who had no interest in astronomy as a young man, randomly chose to go into this field because his original interest did not work out, and made such an impact on Astronomy!  Harlow Shapley will forever go down in astronomical history as a vital part of the sciences.

Works Cited

"The Bruce Medalists: Harlow Shapley." SSU Department of Physics & Astronomy. Web. 20 May 2011. <http://www.phys-astro.sonoma.edu/brucemedalists/Shapley/index.html>.

"Harlow Shapley." The Franklin Institute. Web. 20 May 2011. <http://www.fi.edu/learn/case-files/shapley/index.html>.

Kopal, Z. "`Great Debate:' Obituary of Harlow Shapley." Astronomy Picture of the Day. 1972. Web. 20 May 2011. <http://apod.nasa.gov/diamond_jubilee/1920/shapley_obit.html>.

APOD 4.7

The Last Launch of Space Shuttle Endeavor

May 16, 2011 marked a very important date in NASA history.  It was the launching of Space Shuttle Endeavor's final mission, STS-134, into Earth's orbit.  This picture was captured only seconds after the powerful launch.  Six astronauts are inside this massive shuttle and were expected to dock with the International Space Station on May 18th.  With them they have brought a special detector, the Alpha Magnetic Spectrometer, that will detect special types of dark matter, antimatter, and strangelets.  Unfortunately, this was one of the last shuttles ever planned to launch from this space station.  It is a marvelous sight that we Floridians will surely miss.

APOD 4.6

Globular Cluster M15 from Hubble

This photograph of globular cluster M15 captured over 100,000 stars spanning about 120 light-years, all surrounding around the center of the cluster.  It is in the direction of the constellation Pegasus.  This particular cluster of stars happens to be the relic of our very own galaxy, the Milky Way.  M15 is noted for being easily visible with only binoculars because it has one of the densest concentration of stars at its center.  It also contains an abundance of variable stars and pulsars, contributing to its visibility.  It is one of only 150 globular clusters left.  Hubble Telescope took this image.  Recent evidence shows that there may possibly be a black hole in the center of M15!!

APOD 4.5

The Antennae

This photograph captured two galaxies, NGC 4038 and NGC 4030, colliding, an event that takes hundreds of millions of years to complete.  This is all happening 60 million light-years away, in the southern constellation, Corvus, and it spans about 500 light-years!  The two galaxies' large clouds and molecular gas are furiously combining, resulting in wild episodes of star formation.  However, the already formed stars in the galaxies are not combining.  What appear to be two arms of the galaxy in this photo, is actually matter being flung extremely far by gravitation tidal forces.  It is from these outward spirals that the combined galaxy got its name- The Antennae. 

APOD 4.4

The Cat's Eye Nebula from Hubble

This is a picture of NGC 6543, also known as the Cat's Eye, taken from the Hubble Space Telescope.  It is located about three thousand light-years from Earth, and has a width of about half a light-year.  This nebula is a classic planetary nebula, representing the brief and final stage in the life of a sun-like star.  The outer pattern of dusty concentric shells was likely produced by shrugging off outer layers.  Unfortunately, we do not fully understand this bizaar, yet glorious, phenomenon, but it is believed that this is the fate of our very own sun.  Luckily, it will not be for another 5 billion years!

APOD 4.3

Sunspot Loops in Ultraviolet

In this picture the Sun looks like a violent, chaotic place, but this is actually a quiet day for the Sun!  The photo is shown in ultravioletn light.  Even the cool, dark regions have a temperature of thousands of degrees celsius.  The sunspot group featured in the picture is named AR 9169 and the gas flowing out of and around it has a temperature of over one million degrees celsius!  We still do not know why the temperature of the gas is so high, but it is believed to be related to the rapidly changing magnetic field loops that channel solar plasma.  Continued research and pictures like these will no doubt further pour knowledge of this mysterious phenomenon!

Zooniverse

Last week I worked on Zooniverse Monday, Tuesday, and Thursday.  I explored The Milky Way Project, Solar Stormwatch, Old Weather, and Galaxy Zoo Hubble.  I found Solar Stormwatch to be the most interesting and have decided to do in depth work on it this week.

APOD 4.2

M74: The Perfect Spiral

This spiral galaxy is considered a "perfect galaxy" because it is extremely photogenic.  M74 is an island galaxy with about 100 billion stars.  It is located in the direction of the constellation Pisces, about 32 million light years away.  Right now, we can see it face on.  The spiral arms of M74 are traced by bright blue star clusters and dark cosmic dust lanes, making them an awe-inspiring sight.  This galaxy spans over 30,000 light years across.  This image covers half the width of the moon.  It was obtained by hours of exposure on the Calar Alto Observatory telescope in a mountain range in Spain, and includes exposure from hydrogen atoms emisson. 

APOD 4.1

MESSENGER at Mercury

At first glance, this picture seems to be of our moon, but it is actually a photograph of Mercury, our innermost planet.  This image was taken by the MESSENGER spacecraft on March 17th, which was the first spacecraft to orbit Mercury.  This was its first color processed image since entering the planet's orbit.  After looking closely, it is easy to see the difference between Mercury and the Moon.  There are light blue and brown areas near the craters, but perhaps the most noticable thing about this image are the long bright rays on the surface of the planet.  This particular ray crater is Debussy.  It is about 50 miles in diameter.  With the MESSENGER spacecraft, we will be able to discover much more information on Mercury!

Astronomy Cast Ep. 163

Auroras

An aurora occurs when the Sun's solar winds crash into the Earth's magnetosphere.  They tend to look ghostly and somewhat creepy, although they are known to be quite beautiful as well.  They move and change color in the sky.  What is actually happening in an aurora is the Earth's magnetic field line is interacting with high-energy particles, or any particles from the solar wind.  The charged particles will follow the magnetic field lines back down to Earth's surface, but they collide with things on their way.  This results in a sort of light show.  Different colors are created, and an amazing sight is developed! I would love to get the chance to see one someday.

Astronomy Cast Ep. 206

Fission

Fission is the opposite of fusion.  In nuclear fission, atoms come apart rather than fuze together.  Energy is given off when nuclei are broken apart.  Fusion occurs naturally throughout the entire Universe.  However, it can also be manipulated by science and used for things such as creating devastating weapons and as a power source.  Sometimes nuclei just are not very stable, and with time they naturally break apart.  In this case, they undergo beta decay or inverse beta decay.  This means a neutron decays into a proton, electron, and energy.  In the case of weapons, we compress two pieces of Uranium-235 into a high-density mass.  Then, rapid fire fission occurs, creating more neutrons, thus more fission.  It is scary to think we have that amount of power and that we are able to manipulate such a natural process.  

Astronomy Cast Ep. 205

Fusion

Fusion is the process of taking two atoms and colliding them into one atom.  Usually by-products are also created along with energy.  Fusion was an essential factor in developing the Universe.  After the Big Bang, only hydrogen existed in the Universe.  But through the process of fusion, the atoms were squeezed and clumped together into heavier and heavier elements.  Fusion is also important because it gives us warmth and light from the Sun.  With fusion bombs we can create destruction.  Also, fusion may be an inexpensive source of energy!  It is not unlikely that we will be able to find more uses for it with the rapidly growing technology of today!

Astronomy Cast Ep. 213

Supermassive Black Holes

Black holes are still very much a mystery to scientists and astronomers.  However, we have learned an incredible amount about them in the recent decades.  Astronomers now believe that there is a huge black hole in the center of every galaxy.  These black holes are thought to be able to contain hundreds of billions of times the mass of our Sun! It is difficult to even imagine such massiveness!  They have event horizons that are bigger than our Solar System! Here, in these black holes, are the most energetic particles in the Universe.  There are also the brightest objects in the Universe.  But the most incredible and most confusing thing about black holes, is that the laws of physics are completely mangled in them.  Because no light escapes black holes, astronomers must detect the active ones indirectly.  The Spitzer telescope uses infrared rays to find the actively "eating" black holes.  Optical and X-ray telescopes have been unable to view the holes.

Observation, March 26

On Saturday, March 26th, I went outside to observe the stars.  Conditions were great for observing the sky.  I was able to make out the Little Dipper (Ursa Minor) and Sirius (Canis Major) perfectly!  I also think I saw Gemini and Orion.  It was awesome!

Observation, March 19

Last Saturday, March 19th, I observed the moon perigee. It was amazing! It was incredibly large as it rose in the east.  It was also much brighter than usual. The moon was absolutely beautiful!

APOD 3.8

Boston Moonrise

On March 19th, the moon was a beautiful sight! It was a full moon that seemed excessively large and bright.  Its exact full phase occurred within an hour of perigee, meaning it was 14 percent larger and 30 percent brighter than a Full Moon at apogee.  In this picture, the moon is rising over Boston, hugging the horizon.  It is slightly distorted by the atmospheric refraction.  This picture was taken from Prospect Hill in Waltham, Massachusetts, about 10 miles from the Boston skyline.  The next time the moon will be seen so large and bright will be May 6th of next year!

APOD 3.7

NGC 6914 Nebulae

This extremely colorful picture reveals the stars, dust, and gas found in NGC 6914.  It is a complex of nebulae.  It lies toward the northern constellation Cygnus and the plane of our Milky Way Galaxy, about 6,000 light-years away.  Within the 1/2 degree wide field shown, both reddish hydrogen emission nebulae and dusty blue reflection nebulae can be seen.  This view spans about 50 light-years.  The region's atomic hydrogen gas is ionized by ultraviolet radiation from the massive, hot, young stars.  This produces the red glow seen.  The dusty blue color is formed by blue starlight reflected by the dusty clouds.  This amazing picture was processed to reveal both colors!

APOD 3.6

NGC 4449: Close-up of a Small Galaxy

This is an image of NGC 4449, also called the small island galaxy, which is about 12 million light-years away.  It is a fairly small galaxy.  It has a width of less than 20,000 light-years, which makes it similiar in size to our Milky Way's satellite galaxy. This picture, taken by Hubble Space Telescope, has been reprocessed to show reddish glow of hydrogen gas.  The reddish glow highlights the regions where stars are forming within the galaxy.  It has several short-lived, massive stars.  NGC 4449 is one of many galaxies found in the constellation of Canes Venatici.  Its interactions with its nearby galaxies are thought to have influenced the star formation within NGC 4449.  So, although large spiral galaxies usually get all the attention, NGC 4449 is a prime example of a small galaxy that can form beautiful stars as well.

APOD 3.5

Planetary Nebula Project

In this picture, there are 9 pictures of planetaries: 3 Messier objects (M27- the Dumbell Nebula, M76- the Little Dumbell, and M57- the Ring Nebula), NGC 6543 (the Cat's Eye Nebula), the Medusa, and the Bug.  Each image was made with detailed narrow band data and they all have the same angular scale- 20 arc minutes (1/3 degree). There is a faint grey circle in the middle of the picture.  This represents the apparent size of the full moon at the same angular scale.  Planetary nebulae are a part of stellar evolution.  It is the process when the core is rapidly shrinking because the star runs out of fuel for nuclear fusion.  This picture represents what will eventually happen to our Sun.  Luckily, it will probably be in another 5 billion years.

Jacobus Kapteyn

Jacobus Kapteyn

Jacobus Cornelius Kapteyn was born on January 19, 1851 in Barneveld, Gelderland, a small province of the Netherlands.  After creating an impressive reputation for his studies of the Milky Way and discovering evidence for galactic rotation, he died on June 18, 1922, at age 71.  

Kapteyn was a Dutch astronomer who attended the University of Utrecht in 1868 where he studies physics and mathematics.  In 1875, he finished his thesis and proceeded to work at the Leiden Observatory.  He then became a professor at the University of Groningen.  Because he did not have an observatory, he volunteered measuring photographic plates, which were taken by David Gill.  Gill was conducting a survey at the Royal Observatory at the Cape of Good Hope.  The final product contained a list of 454,875 stars in the Southern Hemisphere and their positions and magnitudes.  In 1897, during his volunteer work, Kapteyn discovered a star with the highest proper motion at the time.  It was named “Kapteyn’s Star”.  

In 1904, Jacobus Kapteyn discovered the first extreme evidence of the rotation of our galaxy.  While studying the proper motions of stars, he determined that the motion of stars being random was a misconception.  In fact, stars could be divided in two separate streams moving in opposite directions.  This evidence eventually led to the discovery of galactic rotation, by Bertil Lindbald and Jan Oort.

Two years later, the Dutch astronomer launched a plan in which the radial velocity, proper motion, apparent magnitude, and spectral type would be measured in 206 zones, in order to measure the distribution of stars in the Galaxy.  This plan involved the cooperation of 40 observatories, and was the first coordinated statistical analysis in astronomy.

In 1913, Kapteyn was awarded the prestigious James Craig Watson Medal, a medal awarded by the U.S. National Academy of Sciences for contributions to astronomy.  He then retired in 1921 and returned to work at the Leiden Observatory.  Here, at the age of seventy, he helped upgrade the observatory to contemporary astronomical standards. 

Jacobus Kapteyn’s life-work was published in 1922, shortly before his death.  It consisted of a theory now called “Kapteyn’s Universe”.  In this theory, the universe is described as “lens-shaped” and the density decreased away from the center of it.  Today, this model is deemed accurate in high galactic altitudes, but fails in the galactic plane because of our modern knowledge of interstellar absorption. 

Several things have been named after him in honor of his great contributions to astronomy.  There is a crater on the moon, the “Kapteyn Crater”, which was named after him, and a telescope located on La Palma in the Canary Islands, the “Jacobus Kapteyn Telescope”.

Reviewing Kapteyn’s great legacy in astronomy, it is no wonder why he is so highly regarded in the astronomical world.  His contributions helped us get to where we are today and he deserves all the recognition he has/is receiving.  One cannot help but wonder what more incredible discoveries he would make if he were still living today!

Work Cited

Dictionary of Scientific Biography, C. Gillispie, editor.  Charles Scribner’s Son. 1981

"Jacobus C. Kapteyn." NNDB: Tracking the Entire World. Web. 25 Feb. 2011. <http://www.nndb.com/people/657/000170147/>.

"Jacobus Kapteyn." Citizendium. Web. 25 Feb. 2011. <http://en.citizendium.org/wiki/Jacobus_Kapteyn>.

APOD 3.4

Colors in Orion

Temperature determines a star's color.  Red stars have a low temperature of about 3,000 K.  Blue stars are much hotter and have a temperature of over 30,000 K.  Our yellow Sun has a temperature of 6,000 K.  In this picture of Orion, several stars of many colors are visible.  It was made of 35 exposures in which the stars were moving left to right through the frame.  The focus was changed in steps.  Ultimately, the stars are shown in a bow-tie shape.  Betelguese is in the upper left of the picture.  It is a bright red star in the constellation.  Betelgeuse is considered a red supergiant.  The Orion Nebula is also visible in the center of the picture in a pinkish color.

Astronomy Cast Ep. 194

Dwarf Planets

Dwarf planets have been debated over for years and years now.  Pluto has recently joined Eris and the astroid Ceres as a dwarf planet, after being known as a planet for several decades.  The demotion of Pluto was triggered by observations of Eris, which was a giant icy body, actually bigger than Pluto.  This also resulted in scientists reanalyzing the rules of being a planet.  The first rule is it must be round.  The second rule is it must be orbiting the Sun.  The third rule is it needs to have cleared out its own orbit.

Astronomy Cast Ep. 210

Mars Exploration Rovers

This podcast discusses the rovers that are currently on Mars.  There are two rovers named Spirit and Opportunity.  They have been on the surface of Mars since 2004, and have outlived what they were expected.  Within the past 6 years we have gained a better understanding about Mars than over the last billion years.  The rovers have discovered land where there were traces of past water.  The rovers are now searching through layers of sediment in search of water.  They will be launching another mission this year in which they will launch an SUV-sized laboratory to probe Mars in search of life.

APOD 3.3

Gibbous Europa

This is a photograph of one of Jupiter's moons, Europa.  It is in its gibbous phase.  Galileo, the robot spacecraft, took this picture during its 1995-2003 mission orbiting Jupiter.  You can clearly see the many features of the moon including its bright ice, dark patches, and long cracks that run down to the horizon.  Europa is smoother than our moon, but it is about the same size.  The Galileo spacecraft gives evidence that there might actually be liquid oceans flowing beneath the icy surface!  NASA and ESA have planned the Jupiter System Mission in hopes of finding life in the oceans.  It will launch in 2020 and it will explore Jupiter, but Europa in particular.  Because the surface of Europa is thin, they hope to be able to drop hydrobots that will break the surface and search for life in the ocean!!

APOD 3.2

Phobos' South Pole from Mars Express

This is a picture of the south pole of Phobos, the closest moon to Mars.  In fact, it is so close that it is expected to crash into Mars within the next 100 million years!  The moon is covered in circular craters, long chains of craters, and strange streaks.  One of the most well known craters, Stickney Crater, is featured in this photograph.  This photo is so detailed that it shows even items that are only 10 meters across.  This and other similar photos are being used to scope out future landing spots for the Phobos-Grunt Mission.  It is scheduled to launch later this year and return with samples in 2014.  I think it is so incredible that we have the technology to take these pictures and to explore the moons of other planets!

APOD 3.1

Saturn Storm

A bright storm erupted on Saturn at the end of 2010.  It was first spotted by amateur astronomers in the northern hemisphere of the planet.  They spotted it in early December when Saturn was rising in Earth's predawn sky.  On December 24th, the Cassini Spacecraft took this photograph from 1.8 million kilometers away.  It is considered a complex distrubance.  The storm has evolved since the picture was taken, and it is now stretches quite far around Saturn. It is pretty amazing that we are able to see such a large storm on another planet!

Pictures of the Sun



Nevil Maskelyne Biography

Nevil Maskelyne

Nevil Maskelyne as born on October 6, 1732 in London, England.  His father, Edmund Maskelyne of Purton ,Wiltshire died when Nevil was only 12 years old.  He left the family extremely poor.  Nevil attended Westminster School.  His mother died when he was 16 years of age, while he was still enrolled at Westminster.  After observing the eclipse of July 25, 1748, his passion for astronomy sparked.  He enrolled at St Catherine’s College, Cambridge in 1749 where he studied mathematics, and was ordained as a minister in 1755.  Being described as “well versed in mathematical learning and natural philosophy”, Maskelyne was admitted to the Royal Society in 1758.  The Royal Society is a fellowship of the world’s most eminent scientists. In 1785, Maskelyne married Sophia Rose of Cotterstock, Northamptonshire, and had his only child, Margaret, in 1786.  He died on February 9, 1811 at the age of 78.

Nevil Maskelyne was first despatched by the Royal Society in 1761 to the Island of St Helena.  Here he was to observe a transit of Venus.  His calculations were vital and needed to be very accurate, because they were to be used to calculate Earth’s distance from the Sun.  In turn, the scale of the solar system would be determined.  Maskelyne was unsuccessful in his observations because of bad weather, however he used his trip as a chance to experiment with determining longitude using the position of the moon.  When he returned to England, he immediately began writing a book.  In 1763, he published the lunar distance method for determining longitude in The British Mariner’s Guide. 

In 1764, Nevil Maskelyne took a voyage to Barbados to carry out trials of Harrison’s timepiece.  When he returned he was appointed Astronomer Royal and published the first volume of the Nautical Almanac in 1766. He continued to work on this project till his death. 

Maskelyne was awarded the Copley medal of the Royal Society in 1775 for his work on determining the Earth’s density.  He carried out an experiment using a plumb line on the mountain Schiehallion in Perthshire, Scotland.  He computed that the Earth’s density is about 4.5 times water’s density.  

Some of Nevil Maskelyne’s other impressive work includes several practical improvements.  He was the first to come up with measurement of time to the tenths of a second!  He was also able to convince the government to replace John Bird’s mural quadrant, an angle measuring instrument, with a repeating circle.  The repeating circle was to be 6 feet in diameter.  Unfortunately, Maskelyne was not alive to see it completed.

Because of Nevil Maskelyne’s extreme passion and dedication to the science of astronomy, we have been able to progress greatly in the subject.  He was clearly a very large contributor to astronomy as we know it today.

Work Cited:

Dictionary of Scientific Biography, C. Gillispie, editor. Charles Scribner's Son. 1981.

"Nevil Maskelyne, Astronomer Royal." Pine Tree Web. Lewis P. Orans, 19 Sept. 2002. Web. 09 Jan. 2011. <http://pinetreeweb.com/bp-nevil-maskelyne.htm>.

APOD 2.5

Stardust in Aries

In this photograph, stardust is sprawled out over about 2 degrees of the sky.  It is located near the constellation Aries and the plane of the Milky Way.  There is also a beautiful light blue nebula, van den Bergh 13, captured in this picture, which is estimated to be about 1,000 light years away.  This means that over 30 light years were captured in the width of this photograph!  Several other dark, dusty nebulae, such as vdB 16, are scattered across the canvas.  How amazing to be able to capture so much in a single picture!