APOD 2.6

December 14th:

      This photo is of a lunar eclipse over an Indian peace pagoda.  This photo captured the moon several times during the eclipse on December 10th.  The photo sequence was captured in New Delhi, India and the red tint of the moon is due to sunlight passing through Earth's atmosphere.  The occurrence of a total lunar eclipse is extremely rare and the next occurs in 2014.

APOD 2.5

December 10th: Vesta Rocks



     The above photos are thin slices of meteorite as viewed through a polarizing microscope.  They are classified as HED's (formed from basaltic magma) and they have reflective spectra that match up with the spectra of asteroid 4 Vesta.  The asteroid is currently being explored by NASA's Dawn spacecraft.

APOD 2.4

Nov. 30 : Curiosity Rover Lifts Off for Mars



     The weekend of November 26th-27th, the Mars Science Lab which carried the Curiosity Rover took off "atop an Atlas V rocket".  An Atlas V rocket (built by Lockheed Martin) was the first rocket in the United States Air Force's Evolved Expendable Launch Vehicle program.  The first Atlas V was launched in August 2002.  The Mars Science Laboratory took off from Cape Canaveral.  Curiosity is five times the size of Opportunity (another Mars rover) and looks like a small car.  It is equipped with a camera, a rock crusher, and is powered by plutonium.

Curiosity:

APOD 2.3

Orange Sun Scintillating

The photograph above was captured using Hydrogen Alpha(usually the brightest wavelength of light in stellar astronomy), so it is falsely colored.  There are many spicules (jets with about a 500 km diameter) visible on the Sun's surface.  Also in the photograph there is noticable color change along the edges of the Sun, this phenomenon is known as limb darkening and is caused by the lower temperatures at the larger heights of the Sun (hence less intense, so darker).  The Sun's magnetic field is moving towards Solar Maximum, the period at which there is the greatest amount of solar activity and sun spots appear, in the next few years.  This means that we can expect a busier, more complex Sun to view in the near future.

APOD 2.2

Historical Supernova Remnant



     RCW 86 is thought to be a remnant of an exploding star that the Chinese discovered in 185 AD.  There was some editing done to this photograph to show the different composition of the supernova.  The blue and green are X-ray energies and the red and yellow are cooler temperatures in infrared.  Because there is a lot of iron present in this supernova but not a neutron star, it suggests that it is a type Ia supernova (thermonuclear explosion that destroys a white dwarf star).  RCW 86 is 8,200 light-years away and has a radius of about 50 light-years.

APOD 2.1

October Skylights (October 28)
                                    
     On October 24th, a coronal mass ejection (gas bubble explosion on the Sun which disrupts solar wind) impacted our magnetosphere, which caused this auroral display.  This picture was taken near Whitby, Ontario, Canada but auroral activity was also noted as far south as Alabama. Aurora consist mostly of electrons that travel along the magnetic field lines.  As they go to the upper atmosphere, they collide with various atoms and molecules, once they collide the atom or molecule stores this energy gained and becomes excited The red color in this picture comes from excited oxygen atoms (above 100 kilometers).  The green color is from oxygen atoms that have returned to the ground state. This phenomenon surely makes for a good photo opportunity.

Observations

10/23
     During this observation session, several constellations were identified.  One that I found particularly easier to find than the others was Sagittarius, probably because of the teapot.   I was also able to see M11 again, which I think is pretty cool.  One thing I was unable to spot was the Andromeda Galaxy, however, some of my friends had success at this.  I also have gotten good at spotting Jupiter, and I now can recognize it even when I'm by myself.

APOD 1.8

Clouds of Perseus
     The constellation Perseuscontains the California Nebula which contains atomic hydrogen gas and the blue star Xi Persei.  In addition to the California Nebula, it also contains the Flying Ghost Nebula.  These dust clouds are hundreds of light years above the galactic plane and they reflect light from our Milky Way galaxy.

APOD 1.7

The Color of IC 1795
     IC 1795 is a region that forms stars in the constellation Cassiopeia.  This picture of IC 1795 shows the dust clouds and glowing gas.  The red color comes from the narrow filter which only transmits the red light of hydrogen atoms.  IC 1795 is located near IC 1805 also known as the Hear Nebula and belongs to a group of star forming regions that are located on the edge of a molecular cloud.  IC 1795 is a little over 6,000 light-years away and spans 70 light-years across. 

Gian Cassini: Biography

     Gian Domenico Cassini was born on June eighth in 1625 in Perinaldo.  Originally given the name Giovanni Cassini by his parents, he changed his name twice throughout his life. After studying in Vallebone, Cassini attended the Jesuit College in Genoa where he studied poetry, math, and astronomy under Casselli. At first, he was interested in astrology as a career, but he soon decided that it was too unpredictable.  In 1644 a senator from Bologna with a passion for astrology offered Cassini a job at the Panzano Observatory.  There he learned a lot from the famed scientists Giovanni Riccioli and Francesco Grimaldi (discoverer of diffraction).  At age twenty five, he became a professor at a university in Bologna where he used telescopes to make planetary observations.  He discovered the flattening of Jupiter, he also concluded this about Earth through his measurement of the arc of the meridian.  Among other things, Cassini observed comets between 1672 and 1707.  He is also known for publishing tables that predicted eclipses of Jupiter’s moons (1668) that were useful to many people.

He moved to Paris, France in 1669 to become part of the renowned Academie des Sciences because Kind Louis XIV invited him.  In 1671 he  became director of the Observatoire de Paris.  In 1673 he officially became a French citizen and adopted his French name Jean Dominique Cassini.  Before moving to Paris, Cassini made many important contributions to astronomy.  He discovered what is known today as the Cassini Division which is the gap between Saturn’s rings A and B.  He also discovered Saturn’s moons.  In addition to these discoveries he also predicted the rotational periods of Jupiter and Mars.  His measurements were later used by Danish astronomer Olaus Romer to calculate the speed of light.  While in Paris at the observatory he became director of a group of astronomers called the Paris School.  In 1673 he married the daughter of an advisor to the king and had two children with her.  His son, Jacques Cassini became an astronomer and also worked at the Paris Observatory.  Later, Cassini’s grandson and great grandson also became astronomers.  Unfortunately, in 1711 Cassini went blind and died in Paris shortly after(1712).

Cassini lived a fairly long life and was very accomplished in astronomy; so accomplished in fact that even today he is still well known.  NASA named a Saturn orbiter and a region on Saturn’s moon Iapetus after him.  However, Cassini was not only accomplished in the field of astronomy; he also worked fervently in hydraulics and engineering.  He was consulted in 1657 in hydraulics regarding the River Reno in order to help settle a dispute between two Italian cities.  Also, in Italy in 1665 he was named Superintendent of waters.  Although the Pope wanted Cassini to permanently work for him, Cassini’s heart was not in it and he decided to remain teaching astronomy and mathematics because that is where his true passion was.  Throughout his career, Cassini was well known for his brilliance in astronomy and good reputation as a scientist.

APOD 1.6

Dark Matter Movie from the Bolshoi Simulation:
     The Bolshoi Cosmological Simulation allows us to simulate a flight through the universe seeing dark matter.  This computer shows us what the beginning of the universe may have looked like because it shows different parts of dark matter such as a microwave background.  Dark matter may contain normal galaxies or clusters of galaxies.  The Bolshoi simulation is thought to be a reliable source of information because it is in agreement with the regular sky maps of today.  The Bolshoi simulation supports the theories of dark matter but we still do not know the composition of dark matter or the nature of it.  Scientists hope to use this simulation to explain how galaxies and other objects in the universe have changed since the Big Bang.

Biography Sources-Gian Cassini

http://www.britannica.com/EBchecked/topic/98187/Gian-Domenico-Cassini

The Gale Encyclopedia of Science

APOD 1.5

          Violent Sunspot Group AR 1302 Unleashes a Flare
     AR 1302 is one of the most active groups of sunspots that is currently crossing the sun.  It is so large that it can be seen without a telescope.  AR 1302's Coronal Mass Ejections (explosions of the Sun's corona which spew out solar particles-can be dangerous if they hit Earth) have caused geomagnetic storms and aurora activity around Earth's poles (blogged about last week).  AR 1302 emitted x-class flares (which can cause radio blackouts and long radiation storms) Thursday and Saturday, which is the largest type of solar flare that can be emitted.  Solar flares occur when there is a release of energy that was previously stored in a twisted magnetic field.  It is thought that AR 1302 will be visible on the Sun for the next week.

Stargazing Observations 9/28/11

     During the stargaze on Wednesday night, I was able to see a lot more than I had anticipated.  While looking through the telescope I saw the globular cluster M13, which I thought was pretty amazing.  Another thing I enjoyed viewing with binoculars simply because I thought it was beautiful was the galaxy.  I never realized how many stars there actually are once you look with binoculars.  Perhaps most interesting, was the planet Jupiter.  Before taking astronomy I never knew that it was even possible to see planets from Earth, but when I actually paid attention, it was obvious that Jupiter was not just another star, I was surprised I never took the time to realize this before. Another thing I saw that was really cool was a satellite, I have probably seen these before, but just thought they were planes.  Needless to say, I will be trying to get out more often and look for interesting things in the sky because stargazing turned out to be very interesting and a lot of fun.

APOD 1.4

September's Aurora
     Today, the Sun crosses the celestial equator and marks the beginning of autumn in the northern hemisphere.  The equinox arrives at 0905 UT today.  The connection between the seasonal change and the aurora ("coronal mass ejection") is still somewhat a mystery however, astronomers know that autumn (and spring) bring an increase in geomagnetic storms.  Although fall offers good conditions for viewing auroras on Earth, the auroras are also visible from space.  Luckily, in space, Earth is surrounded by a magnetic field when this occurs which protects us from solar winds. 
     This is a truly amazing phenomenon which I think all people should see in person at least once.  If it looks this beautiful in pictures, it must be breath taking in person.

Previous observations

Earlier this week we discussed how Jupiter could be seen if we woke up early enough to actually look for it. Instead, I opted for a later viewing and waited until it got dark enough outside to clearly see the moon and stars. (I don't live around much,so it was fairly easy to see). I am pretty sure I actually saw Jupiter because I double checked with my binoculars, although they did not help that much. I am not sure if this was Jupiter because it was on the side of the moon and in class we discussed how it had been above it.

Observation

I have been watching the moon for the past few days now and really noticed a differernce in the phases. I noticed that yesterday, september 20th the moon Was at last quarter. Tonight it seems to be a waning crescent, which makes sense according to what we've been discussing and learning in class.

APOD 1.3

Great Orion Nebulae:

     Great Orion Nebulae include the Great Nebula in Orion (M42) and also a smaller nebula such as NGC 1977 (M43).  At the center of M42 and M43 exists a giant, interstellar gas and dust cloud. The cloud spans several hundered light years across and was formed by a density wave.  From reading about these two nebulae, I learned that astronomers have detected what they believe to be infant planetary systems within the nebulae.  However, astronomers also found that the disks (what would be future planets) are being blasted with UV radiation from the brightest star in the region, which makes planetary formation difficult.  One thing I found amazing is that Orion's Nebula's approximate distance is about 1,500 lightyears.

APOD 1.2

SDSS J102915+172927: A Star That Should Not Exist
     This Milky Way star has fewer metals in it than any other star known to man.  Population I stars have elements heavier than hydrogen and helium and are rich in metals, Population II stars have some elements heavier than hydrogen and helium but are less rich in metal, and Population III stars are composed largely of primordial gas. SDSS J102915+172927 is strange because it is a low mass star and it has fifty times less lithium than came out of the Big Bang. Also, according to ESO this star is composed entirely of hydrogen and helium with only trace amounts of other elements.  According to the study of star formation, SDSS J102915+172927 should not even exist although it is believed to be about 13 billion years old. Astronomers are continually testing different theories of how this could have happened, but there is one leading hypothesis that the fragile lithium was destroyed in the star's core.

APOD 1.1

  The Fairy of Eagle Nebula  

     While reading about this photograph, I first read about dust pillars which are described as interstellar mountains that exist because they are more dense than their surroundings. These dust pillars are part of the Eagle Nebula(M16), which is an open cluster of stars in the constellation Serpens.  It was first discovered by Jean-Philippe de Cheseaux, a Swiss astronomer in 1745-1746.  It is called Eagle Nebula because the shape of the actual nebula itself resembles an eagle.  The evaporating gas and dust in the nebula form a whole nursery of stars.  The Fairy of Eagle Nebula is ten light years tall, and gives off radiation hotter than fire...quite the fairy.