Wednesday, September 30, 2009
Do you remember NASA's Deep Impact mission of July 4, 2005, which punched a spectacular hole in Comet Temple 1 in order to see what was inside? Well, as Yankee's great Yogi Berra would say, its “déjà vu all over again.” Only this time the target is a lovely crater at the South Pole of the Moon.
The mission is NASA's Lunar CRater Observation and Sensing Satellite, or LCROSS for short. The mission objectives of LCROSS include confirming the presence or absence of water ice in a permanently shadowed—and therefore always cold--crater at the Moon’s South Pole. As mentioned here a few days ago with the Chandrayaan-1 announcement, the identification of water is very important to the future of human activities on the Moon. LCROSS will excavate the permanently dark floor of one of the Moon’s polar craters with two heavy impactors to test the theory that ancient ice lies buried there. The impact will eject material from the crater’s surface to create a plume that specialized instruments will be able to analyze for the presence of water (in the forms of ice and vapor), hydrocarbons and hydrated materials.
Like on Earth, water is a crucial resource on the Moon and it won't be practical for humans to carry with them all of the water they will need. It is critical to find natural resources, such as water, on the Moon. The LCROSS mission will begin NASA's direct search for water, leveraging the information that was learned from NASA'S Clementine and Lunar Prospector missions.
By going first to the Moon and staying there for extended periods of time, astronauts can search for resources and learn how to work safely in a harsh environment before moving out to other bodies in our solar system. In addition, a close up and extended study of the Moon can offer scientists insight to the time when the planets were formed.
A sister mission working with LCROSS is NASA's Lunar Reconnaissance Orbiter, or LRO. From lunar orbit, LRO will scout for safe and compelling landing sites for future missions, locate potential resources (with special attention to the possibility of water ice) and characterize the effects of prolonged exposure to the lunar radiation environment. In addition to its exploration mission, LRO will also return rich scientific data that will help us to better understand the moon’s topography and composition.
Back on June 18, LCROSS and LRO began their mission from Launch Complex 41 at Cape Canaveral Air Force Station, aboard an Atlas V first stage with a Centaur upper stage. Since then, the mission teams have been using their returning data, along with data from current and past lunar missions (those previously noted as well as ISRO's Chandrayaan-1 and JAXA's Kaguya spacecraft), to refine the South Pole target for the LCROSS impactors.
Until recently the target was crater Cabeus A, a companion to crater Cabeus (proper). Then on Monday the LCROSS mission announced it was shifting the target to Cabeus (proper). The latest data now seems to show that Cabeus has the highest hydrogen concentrations at the South Pole. Also, the latest terrain models show a small valley in an otherwise tall Cabeus perimeter ridge, which will better allow sunlight to illuminate the ejecta cloud—the stuff flying out from the impact—on October 9, which is the scheduled date for the event. While this target change means that the ejecta will have to fly a little higher before it is visible to ground-based and Earth-orbital telescopes, a shadow cast by a large hill along the Cabeus ridge, will provide an excellent, high-contrast, back drop for ejecta and vapor measurements. The first impactor will be the Centaur upper stage, which has been guided by the LCROSS spacecraft. Following its observations of the first impact, LCROSS itself will then dive in, creating the second impact.
The exact time of the impact is early Friday morning, October 9, at 7:30 a.m. EDT/4:30 a.m. PDT. As the date gets closer, mission teams will continue to refine the target, choosing the exact point of impact within Cabeus crater in order to avoid rough spots, and to maximize solar illumination of the expected debris plume and Earth observations. Scientific benefits aside, it looks to be a great show. If you happen to be at a location where the Moon is visible at that time, and if you have a telescope with a 10” to 12” aperture, you might want to gather some friends for a LCROSS impact party. It should be fun. Just be sure to observe and party responsibly.
To keep current on the missions as they progress, stay tuned to these sites:
NASA's Lunar CRater Observation and Sensing Satellite (LCROSS) Mission
NASA's Lunar Reconnaissance Orbiter (LRO) Mission
Tuesday, September 29, 2009
Last Friday evening—September 25th—a meteor streaked across the sky over southern Ontario and the Greater Toronto Area (locally abbreviated as the GTA). The event was seen just after 9 p.m. Eastern Daylight Time. Many described the light as a greenish color and that its brightness was greater than that of the full Moon—qualifying the object as a fireball. Some Toronto security cameras under the fireball's path actually caught the dramatic change in brightness at ground level as the fireball passed. One security camera actually caught a reflection of the fireball in the paint job of a parked van.
After a few seconds of fame, the meteor broke into reddish fragments and faded from view. Some described the meteor as a bolide since it broke up in flight. My understanding of a bolide is that the exposition would be more violent than what was reported, and that it would normally be accompanied by sonic boom-like sounds. Neither of these occurrances was reported in the story, but no matter. By whatever you call it, the event was spectacular.
So what do we really know about the object? When all is said and done, not much. But that has never stopped us before. Let’s pretend that we are a bunch of amateur astronomers sitting around a jolly table with a tasty beverage in hand. What can we guess about the object—and guessing is definitely what we are doing here.
Was this really a meteoroid or was it space junk? Good question. Since the newspapers did not report any official announcement of “something” expected to fall on that evening, I’m guessing that it was not space junk. If it was, though, shame on them for missing it. Let’s stay with the meteoroid guess.
About how big was it? Well, fireballs are thought to be the result of meteoroids that range in size from a basketball to a small car. At least, that would be the size range when it entered the atmosphere. It would have gradually broken up on its way down until it finally did that major breakup at the end.
What kind of meteor was it? Well, we don’t have details in the news story as to its direction, so we cannot even extrapolate an orbit that my suggest a possible family of Near-Earth asteroids, so we will have to let that one go. With regard to its composition, we can take a wild guess. The witnesses report that it was bright green. That is one of the usual colors seen of fireballs, along with blue, yellow, red, or even white. The color green can be an indication of the presence of the mineral nickel, so perhaps it was a nickel-iron meteoroid, and therefore produced nickel-iron meteorites.
Can we find the meteorites? Well, that depends on whether someone was close to the break-up point, and has a good idea of the general location. If they are nickel-iron meteorites, and that is a very wild guess, then they would be easier to spot than stony or stony-iron meteorites, which tend to blend in with the surrounding rocks. One think to look for is a crusty, charred exterior, as if someone took a large knife and carved big chunks out of the surface, creating interestingly shaped rocks. This carving appearance is the result of the ablation process as the meteoroid passes through the atmosphere. The surrounding air molecules are compressed, heat up, and ionize the gas around the meteoroid. As the outside of the meteoroid heats up, parts of the exterior pop off, taking the excess heat with them and allowing the larger body to survive intact for at least a little longer. If you do see a meteor, and if it comes down near your location, look around as best you can. If you do find something that you think might be a meteorite, take it to the nearest university, science museum or science center. Talk to the most knowledgeable person there on the subject of meteorites. Tell them all you can about the rocks and where you found them. If that person agrees with your opinion, they may need to send it off to someone for testing, or perhaps do the tests themselves. And if you’re lucky, you might have found a meteorite.
Why didn’t astronomers warn anybody about this one? Well, that goes back to its size. Official watch groups, like the participants in NASA’s Near-Earth Objects program, only look for bodies that are a kilometer in size or greater. The smaller stuff is just too small to consistently spot. And besides, statistics show that the smaller stuff usually breaks up well before hitting the ground, like this one did, or falls in water or in a remote area. The numbers say that bigger stuff is possible on the average of every one hundred years or so, like the Tunguska event over northern Russia on June 30, 1908. Wait, you say. It is now 2009. Are we statistically due for another Tunguska-sized event? Oh, I see you have been watching the History Channel. Me, too. Well, to be a concern, the body would have to affect a populated area, not a remote area or a body of water. Beyond that speculation, I’m not even going further. That topic is for the professionals.
If you really want to know about Near-Earth objects, then NASA’s Near Earth Object Program is definitely the place to check out. The folks in this group are constantly looking for bodies that might be a concern to Earth either now or in the future. As of September 27, 6,386 Near-Earth object have been discovered by them. These are bodies orbiting our Sun which come close to Earth every now and then. Knowing who our neighbors are and where our neighbors are is the first step in avoiding our neighbors, if you know what I mean. As I say these folks are dedicated and do a great job. And the site is very informative, too. Summing up, I would say that since these groups are diligently working away, it is a good chance that anything that would be a concern to us would be reported in the news well in advance of a possible problem. So please don’t worry your pretty little head about it.
Gee, that was fun. And I’m in need of another tasty beverage, so I’ll leave you now. But if you want to learn more about observing meteors and finding meteorites, or about Near-Earth objects, please check out these great sites:
American Meteor Society
International Meteor Organization
NASA's Near Earth Object Program
Monday, September 28, 2009
The Planck mission has produced its first rough images of the ancient sky, demonstrating that the new observatory is working and ready to measure cosmic microwave background radiation—ancient light from the dawn of time.
Cosmic microwave background radiation, or CMBR for short, is thought to play a key role in the field of cosmology—the study of the origin and nature of the universe. CMBR is a form of electromagnetic radiation which fills the universe. While the space between the stars and galaxies appears pitch black in an optical telescope, a radio telescope reveals a faint background glow, almost exactly the same in all directions, that is not associated with any star, galaxy, or other object. This glow is strongest in the microwave region of the radio spectrum, leading to the name cosmic microwave background radiation. CMBR was discovered in 1964 by radio astronomers Arno Penzias and Robert Wilson and was the culmination of work initiated in the 1940s. Their discovery earned them the 1978 Nobel Prize.
According to the Big Bang model of cosmology, before the formation of stars and planets, the universe was much smaller, much hotter, and filled with a uniform glow from its white-hot fog of hydrogen plasma. As the universe expanded, both the plasma and the radiation filling it grew cooler. When the universe cooled enough, stable atoms formed. These atoms were no longer able to absorb the thermal radiation, and the universe became transparent instead of being an opaque fog. The photons that existed at that time have been traveling ever since, though growing fainter and less energetic, since the exact same photons fill a larger and larger universe.
The objective of the Planck mission is to detect and map these ancient photons. Planck is a European Space Agency (ESA) mission that has significant participation from the National Aeronautics and Space Administration (NASA). NASA played key roles in the development of the Planck mission and is providing important contributions to the science analyses of mission data.
The mission is named after German physicist Max Planck (1858 – 1947), considered to be the founder of quantum theory. The Planck mission was launched (along with the Herschel mission) on May 14, 2009 aboard an Ariane 5 rocket from Europe’s Spaceport in French Guiana. Since July 2, Planck has been orbiting the Earth-Sun Lagrange Point 2 (L2), about 1.5 million kilometers (930,000 miles) from Earth in the direction opposite the Sun. This dark location, combined with an onboard cooling system, allows Planck to be very cold indeed, with an operational temperature of -273.05°C (-459.5°F). This temperature allows Planck’s detectors to study the CMBR.
And extensive checkout and initial calibration of Planck's instruments was completed by the second week of August. Planck's "first light" survey, which ran continuously from August 13 to 27, verified the stability of its instruments and their ability to be calibrated over long periods to the extreme accuracy that is needed. The survey produced maps of a 360° strip of the sky, one map for each of Planck's nine observed frequencies. Preliminary analysis indicates that the quality of the data is excellent.
Astronomers expect that Planck will provide the best views to date of the early moments of our universe, over 13 billion years ago. Planck will survey the entire sky continuously for at least 15 months, yielding at least two full and independent all-sky images. The mission promises to contain a treasure trove of data that will keep cosmologists and astrophysicists busy for decades to come.
The Planck mission follows in the footsteps of previous missions which studied the CMBR, including NASA's Cosmic Background Explorer (COBE) , NASA's Wilkinson Microwave Anisotropy Probe (WMAP) , NASA's and the Netherlands (NIVR) Infrared Astronomical Satellite (IRAS) , and other orbital and ground-based missions. For more on the Planck mission and earlier CMBR missions, check out these sites:
Planck Mission, ESA Home Page
Planck Mission, NASA Home Page
NASA’s Legacy Archive for Microwave Background Data Analysis
NASA's Cosmic Background Explorer (COBE) Archive Page
NASA's Wilkinson Microwave Anisotropy Probe (WMAP) Archive Page
NASA's and the Netherlands (NIVR) Infrared Astronomical Satellite (IRAS) Archive Page
Sunday, September 27, 2009
Acts 16:1-3; 2 Timothy 1:1-5; 3:14-17
Who built a foundation for your faith in Jesus Christ? Who helped you understand the gospel? Who was present when you asked Jesus to be your Savior? Who influenced you on your spiritual journey? Was it a parent? A grandparent? Another family member? A close friend? Who was your Paul?
Timothy may have been converted to faith in Christ on Paul’s first missionary journey to Lystra, a city in what is now modern Turkey. When Paul returned to Lystra on his second journey, he found that Timothy was well respected by other believers for this faith.
In Paul’s second letter to Timothy, Paul addressed Timothy as his son, indicating a close relationship between them. Paul described Timothy’s faith as sincere and that it first lived in his grandmother and his mother. Timothy grew up in a family that nourished his faith from their own.
Paul reminded Timothy to do those things he had learned. Timothy did not learn the truth from strangers, but from people close to him who lived out Scripture teachings. Timothy’s personal knowledge of his teachers assured him of the reliability of the things he had learned. The content of the teaching was important, but so was the character of those who taught him.
Paul asserted to Timothy that the Scripture guides, corrects, and helps us to know what to do and how to act. The Scriptures can lead people to wisdom and then salvation. Just knowledge of the truths of Scripture is not enough. Saving faith comes only through trusting Jesus as Lord and Savior. Faith in Christ is the link which unites the message of the entire Scripture.
As a Christian, you can help others to hear and know what the Bible says. You can be a Paul to someone else. You can help them begin to do what the Bible says to do. You help build foundations in the lives of others so they will know how to live for God. Who will be your Timothy?
Saturday, September 26, 2009
The science teams for NASA's Mars Reconnaissance Orbiter (MRO) mission have been very busy of late, studying images of sub-surface water ice on the planet Mars. The images were taken by MRO’s High Resolution Imaging Science Experiment (HiRISE). The images show craters that were dug by meteorite impacts in 2008. One crater is 12 meters, or 40 feet, across and is located within Arcadia Planitia. Another crater is 8 meters, or 26 feet, across on the flat, dark plains of Vastitas Borealis. When HiRISE found these recent additions to the Martian surface, it also found something very exciting—ice. Other MRO mission instruments were put into play and the teams soon confirmed they were looking at sub-surface water ice that was 99 percent pure.
This discovery provided two big surprises about Mars. The first surprise was that the exposed water ice was so pure. They previously thought that the ice would accumulate between the soil grains, creating a 50-50 mix of dirt and ice. But by watching the ice slowly fade in progressive images, they estimate the mixture to be about one percent dirt and 99 percent ice. The second surprise was that, while scientists expected ice beneath the Martian surface at high latitudes, they did not expect it to stretch at least to 48 degrees of latitude—over halfway to the equator. This amazing discovery could have a major impact on the future and direction of Mars exploration. But what if this discovery had been made earlier? Say, 30 years earlier?
Flash-Back Time… Do you remember NASA’s Viking program? I sure do. It consisted of two ambitions orbiter/lander missions to Mars. Viking 1 launched August 20, 1975 and Viking 2 launched September 9. The probes reached Martian orbit on June 19 and August 7, respectively, of 1976. The Viking 1 Lander reached the surface July 20 and the Viking 2 Lander on September 3. Viking 1 touched down in Chryse Planitia (Greek for “Plain of Gold”) and Viking 2 landed in Utopia Planitia (Greek for “Plain of Utopia”). Trekkers in the know will remember that the U.S.S. Enterprise D, from TV series Star Trek: The Next Generation, was assembled in the Utopia Planitia Yards, a nod to the amazing achievements of the Viking program. The various Viking crafts operated for a significant time. Orbiter 2 until July 25, 1978, Lander 2 until April 11, 1980, Orbiter 1 until August 17, 1980, and Lander 1—the old man of the program—operated until November 13, 1982. Their combined data provided most of our knowledge about the Red Planet well into the early 2000s.
Viking was pretty big for me. Like many other teenagers in the southeastern U.S., I got an opportunity to see the mission up close and personal. It was, of course, 1976, the year of the U.S. Bicentennial celebration. NASA's Kennedy Space Center was hosting Third Century America, an exposition of what American science and technology had achieved and what was possible in the future. The event was assembled around the south end of the Vehicle Assembly Building and featured an Apollo Saturn V launch vehicle on display and a collection of geodesic-domed pavilions filled with exhibits. One pavilion featured a full-scale model of a Viking Lander with updates on the Lander activities and real-time feed of the downloaded images.
But what if those downloaded images had included sub-surface water ice? What if Viking had discovered it? The relative location of at least one of these meteorite craters is near to the Viking 2 Lander site. Could Viking 2 have discovered it? Well, the Viking scoops were designed for mission experiments to test the soil for organic compounds that would indicate the presence of current or past life. They were not designed to dig deeply, like the Mars Polar Lander of 1999 or the Phoenix Lander of 2008. But what if they had? What if those scoops were able to dig just three or four inches deeper? We would not have had to wait until the Mars Polar Lander (which failed) or the Mars Phoenix Lander before we saw water ice in the Martian soil. How would that discovery have affected our perception of Mars and the exploration of Mars for the next twenty years? Would this knowledge have encouraged the budgetary support for more robotic Martian probes through the 1980s and 1990s? Would the talk of human exploration of Mars have become a reality by now? Maybe…and maybe not.
The important question for us now is this: How does this discovery affect our perception of Mars and Mars exploration now? Will this encourage the budgetary support for more robotic probes? Will the talk of human exploration of Mars become a reality sooner than later?
To learn more about the discovery of sub-surface water ice on Mars, and to learn more about Mars exploration, please check out these great sites:
HiRISE Home Page
NASA’s Mars Reconnaissance Orbiter Home Page
NASA’s Mars Exploration Program Home Page
NASA’s Mars Polar Lander Mission Home Page
NASA’s Phoenix Mars Mission Home Page
NASA’s Viking Mission Home Page
Friday, September 25, 2009
The scientific community is all a-buzz today, using phrases like "definitive," "clear evidence" and "unequivocally confirm." Of what do they speak? Why of the presence of water on the Moon, a world previously thought, for the most part, to be as dry as a bone.
The new evidence comes from three corroborating sources. The first is the Moon Mineralogy Mapper, an instrument developed by the National Aeronautics and Space Administration (NASA) and flown on Chandrayaan-1, India’s first robotic lunar probe. The second source is the Deep Impact spacecraft, which made its discoveries on two fly-by’s of the Moon during it's current extended mission (EPOXI). The third source is NASA’s Cassini spacecraft.
The new data shows that over the course of the long lunar day, a water only a few molecules thick—described by some as “dew”—gradually forms on the lunar surface and then gradually dissipates. Scientists are not certain how this happens, but they think the cycle is driven by the sun. They suggest that hydrogen ions are carried by the solar wind to the Moon where they interact with oxygen rich minerals in lunar soil and rock to produce the molecules for water and hydroxyl. The molecules form in the cooler lunar morning and then evaporate in the warmer lunar mid-day. Scientific reports estimate that one ton of lunar surface containing the molecules could naturally yield as much as 32 ounces, or one quart, of water. While this amount is not large, scientists note that there are ways to increase the output. What’s more, scientists suspect that if their theories regarding the process are correct, then this is happening throughout the inner solar system on all airless bodies with oxygen-bearing minerals.
This is very exciting news, but, for now, there are a few hurdles that sill need to be cleared. The discovery must be confirmed to everyone's satisfaction. The resource finds must be in sufficient quantities to be usable. And the resources must be cost effectively accessible. If all of these issues can be addressed, this is major. Just think about it. Once the necessary extracting, processing and storing facilities were up and running, future explorers would no longer have to "bring their own everything" when they left the safety and comfort of Earth. Instead, they could pack the minimum essentials for a short hop and let the Moon provide the rest. This would include water for drinking and farming, oxygen for breathing, and the combination of hydrogen and oxygen for rocket fuel. This turn of events could give a tremendous boost to the arguments for using the Moon for colonization and as a platform for future solar system missions. In addition to the possible benefits to space exploration, there are those that are considering, with the presence of water, the possibility of life on the Moon. Whatever the final outcome, this discovery should definitely boost budgets for lunar exploration in the short term.
Chandrayaan-1 was India's first robotic lunar probe, managed by the Indian Space Research Organisation (ISRO). The word “Chandrayaan” is Sanskrit, meaning “Moon-vehicle” or "Lunar Craft.” Chandrayaan-1 was launched from Satish Dhawan Space Centre Sriharikota on October 22, 2008. Designed for a two-year mission, it ended after only 312 days when radio contact was lost on August 29. Even with this loss, mission managers were able to achieve 95 percent of the planned objectives. The spacecraft carried eleven scientific instruments. Five were Indian, three were from the European Space Agency (ESA), one from the Bulgarian Aerospace Agency, and two were from the National Aeronautics and Space Administration (NASA). One of these was the Moon Mineralogy Mapper .
NASA’s Deep Impact spacecraft was originally built for is 2005 mission in which it successfully punched a hole in comet Tempel 1 in order to find out what was inside. The spacecraft's data on lunar water were obtained as part of calibration opportunities that occurred during two June flybys of the Earth and Moon, which were needed to get a sufficient gravity boosts to travel on its EPOXI mission to a second comet, Hartley 2, which the spacecraft will encounter in November 2010.
NASA’s Cassini-Huygens mission was launched October 15, 1997 and is currently orbiting Saturn, studying the planet, its ring system and its moons.
For the latest on the discovery, please check out these sites:
Chandrayaan-1 Mission Home page: http://www.isro.gov.in/Chandrayaan/htmls/home.htm
NASA’s Moon Mineralogy Mapper home page: http://m3.jpl.nasa.gov/
NASA’s Cassini Mission home page: http://www.nasa.gov/mission_pages/cassini/main/index.html
NASA’s Deep Impact Mission home page: http://www.nasa.gov/mission_pages/deepimpact/main/index.html
NASA’s EPOXI Mission home page: http://epoxi.umd.edu/
Thursday, September 24, 2009
In an effort to encourage the growth of amateur planetary astronomy, I thought I would try to inspire you with a just a taste of the neat things that are possible for the amateur with decent equipment, careful planning and a bit of patience. A planetary astronomer is one who concentrates their observing efforts on bodies orbiting within our solar system. And of the easily visible planetary bodies, one of the most consistently satisfying, if not the most satisfying, is Jupiter.
If you look up into a clear night sky, you can see the planet Jupiter. After Earth’s moon, Venus and sometimes Mars, it is the brightest object in the heavens. It looks like a very bright object but it doesn’t twinkle like a star. It has a bright, steady glow.
Because Jupiter can be seen from Earth, people have observed it for thousands of years. Ancient civilizations had no way of knowing that they were really looking at a planet, but they knew that it was different from the stars. They knew it was different because, unlike the stars, it seemed to move across the sky in a unique way. In fact, the word “planet” comes from the Greek word for “wanderer.”
The planet is named for the king of the gods in the Roman pantheon. Also called Jove, but known to the Greeks as Zeus, he overthrew his father Saturn (in Greek, Cronus). He then drew lots with his brothers Poseidon and Hades to determine who would be the supreme ruler of the gods. Jupiter won the draw and became the ruler of Olympus and the patron of the ancient Roman state. Jupiter was the rain god and lord of the sky. His weapon is a thunderbolt which he hurls at those who displease him. He is married to Hera, but is famous for his many affairs. He is also known to punish those that lie or break oaths.
It was not until the invention of the telescope in the early 1600s that people were able to take a closer look at Jupiter. When the Italian astronomer Galileo Galilei turned his homemade telescope toward Jupiter in 1610, he saw a huge striped world with moons of its own. However, not much else was discovered about the giant mysterious planet for hundreds of years.
In the 1970s, the Pioneer spacecraft were sent to Jupiter. There were soon followed by the two Voyager missions an eventually by Galileo, the spacecraft named after the astronomer, which was launched in 1989 and which plunged into Jupiter’s atmosphere at the conclusion of the mission in 2003.
What has been learned about the planet from these missions is truly amazing. Jupiter isn’t a planet as we normally think of one—it’s actually a giant ball made completely, or almost completely, of liquid and gas. It has more moons than any other planet and is often viewed as its own mini solar system. The size of the planet is astounding, encompassing two-thirds of all the planetary mass in the solar system.
The environment of Jupiter is one of powerful storms, incredible lightning, deadly radiation, and winds many times faster than those of the strongest hurricanes on Earth. Scientists continue to be fascinated by the planet.
However, it is not just the planet that interest scientists and astronomers today. The moons, or satellites, of Jupiter are also subjects of intense study. And with forty-nine moons officially named so far, there is a lot to be learned.
Lately, much attention has been focused on the fact that liquid water has been detected on several of Jupiter’s moons, suggesting that the moons may once have had, or may currently have, some form of life since water is necessary for life as we know it. Europa, the sixth moon from Jupiter, is considered by many to be, along with Mars, among the likeliest places outside of Earth to find evidence of life.
We are just over halfway through Jupiter’s current apparition, which is a fancy way of saying the current appearance of Jupiter from its last Solar conjunction until its next conjunction. Jupiter's last Solar conjunction was January 24, 2009, and it was at opposition (opposite from the Sun in our sky) on August 14. It will next be in conjunction on February 28, 2010. This means that Jupiter is past its visual prime for this time around, but it is still a sight to behold for those who take the time and make the effort.
Some of those who make this effort are the members of the Association of Lunar and Planetary Observers, the A.L.P.O. This international organization studies the Sun, Moon and the solar systems planets, asteroids, meteors, comets. The goals of the A.L.P.O. are to stimulate, coordinate, and generally promote the study of these bodies using methods and instruments that are available within the communities of both amateur and professional astronomers. Incidentally, if you happen to speak with a member of the A.L.P.O., you would do well not to make humorous references to a certain brand of dog food. I mention this for your own good…
A.L.P.O. members are encouraged to submit their observations for comparison and study. The most interesting are regularly published for the benefit of the members and the general public. The Jupiter observations appear in the weekly Jupiter Newsletter. This electronic publication is edited and posted by my good friend and fellow amateur Craig MacDougal, who is an Assistant Coordinator for the Jupiter Section of the A.L.P.O. The Jupiter Newsletter may be found on the A.L.P.O. Jupiter Section page (http://www.alpo-astronomy.org/jupiter/). The newsletter link is located near the bottom of the page and is appropriately called "The ALPO Jupiter Newsletter."
And while you are on the Jupiter Section site, if you really want to get an idea of what is possible for the amateur observer, I encourage you to check out the link at the top of the page called "Jupiter Observations and Alerts." Within it you will find a wonderful sampling of images from various member observers stretching from 2007 back to 2005. You will see fine examples of digital imaging and pencil drawing--yes, people still do that.
I’m afraid that is all I have for now, but we will revisit the Jupiter system soon. To learn more about Jupiter and Jupiter observing, please check out these sites:
The Galileo mission home page
The Jupiter page of NASA/JPL's Solar System Exploration site:
A.L.P.O Official Site
A.L.P.O. Jupiter Section
Wednesday, September 23, 2009
New Horizons is Halfway There
On September 8, NASA's New Horizons mission passed the halfway point on its way to the outer solar system. On July 14, 2015, if all goes well, the grand-piano sized robotic spacecraft will unveil the mysteries of Pluto and the Kuiper belt. The journey began January 19, 2006 from Launch Complex 41 at Cape Canaveral Air Force Station. New Horizons departed aboard a mighty Atlas V rocket, leaving earth orbit at over 58,500 kph--the fastest speed on record for an outward bound spacecraft. The probe flew past Jupiter on February 28, 2007, where it got a gravitational boost, adding about 14,000 kph to its velocity. The spacecraft will spend much of the remaining trip in hibernation but will be awakened periodically by engineers for checkup in order to make sure that and all systems are healthy and ready for the historic encounter. The last checkup was completed August 27 and the next will not begin until November 9. In the mean time the craft sleeps peacefully as it speeds between the orbits of Saturn and Uranus.
The spacecraft will fly by and study Pluto and its three known moons, Charon, Nix, and Hydra. And the journey does not end there. Depending on the success of the flyby and the health of the craft, NASA may approve flybys of one or more other Kuiper Belt Objects.
Here are some interesting facts about Pluto and the New Horizons mission.
Eight Facts about Pluto and Kuiper Belt
1. Pluto is named after the Greek god of the underworld. Its Roman counterpart is Hades.
2. Pluto orbits the sun once every 248 years.
3. A person on Pluto would weigh 1/15 what they weigh on Earth.
4. The symbol for Pluto has a double meaning. While it is an artistic combining of the first two letters of the name Pluto ("P" and "L"), it is also a tribute to Percival Lowell, who began the search for a ninth planet in the early 1900s.
5. Pluto was discovered in 1930 by American astronomer Clyde Tombaugh at the Lowel Obervatory.
6. In honor of the discovery, Walt Disney named Mickey Mouse's dog after Pluto.
7. Pluto was considered a planet until August 24, 2006, when the International Astronomical Union (IAU) voted on a definition for solar system planets. It was then determined that Pluto would be the first of a new category of solar system bodies called dwarf planet, though this redesignation—some say demotion--is disputed by various members of the astronomical community. The IAU definitions continue to be a topic of great debate.
8. The Kuiper (rhymes with “viper”) belt was first discovered in 1992. It is a region of the solar system beyond the planets extending from the orbit of Neptune ( 30 astronomical units) to approximately 55 astronomical units from the Sun. It is similar to the asteroid belt, although it is much larger—20 times as wide and 20–200 times as massive. Like the asteroid belt, it consists mainly of small bodies, or remnants from the solar system's formation. While the asteroid belt is composed primarily of rock and metal, the Kuiper belt objects are composed largely of frozen volatiles (termed "ices"), such as methane, ammonia and water. The region is known to include over a thousand Kuiper belt objects (KBOs), and it is home to at least three dwarf planets – Pluto, Haumea and Makemake.
Five Facts about New Horizons
1. New Horizons is the first mission in NASA's New Frontiers mission category, larger and more expensive than NASA's Discovery missions but smaller than the NASA'S Flagship Program. The cost of the mission (including spacecraft and instrument development, launch vehicle, mission operations, data analysis, and education/public outreach) is approximately $650 million over 15 years (from 2001 to 2016).
2. The New Horizons craft was built primarily by Southwest Research Institute (SwRI) and the Johns Hopkins Applied Physics Laboratory (APL). The mission's principal investigator is Dr. S. Alan Stern (NASA Associate Administrator, formerly of the Southwest Research Institute).
3. The New Horizons Mission to Pluto and the Kuiper Belt is managed by Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland.
4. The initials of the mission name New Horizons (N and H) are a tribute to Pluto’s two most recently discovered moons, Nix and Hydra.
5. Other items traveling with the spacecraft include, among other things, a collection of 434,738 names stored on a compact disc, a piece of Scaled Composites SpaceShipOne, and an American flag. One of the trim weights on the spacecraft is a Florida state quarter, and New Horizons principal investigator Alan Stern has also confirmed that some of the ashes of Pluto discoverer Clyde Tombaugh are aboard the spacecraft.
For more on New Horizons, check out the mission home page: http://pluto.jhuapl.edu/
For more on Pluto and the Kuiper belt, visit this page of the NASA/JPL’s Solar System Exploration site: http://sse.jpl.nasa.gov/planets/profile.cfm?Object=Pluto
Tuesday, September 22, 2009
Alexander Means was described in his day as a polymath--a person with extensive learning in several fields of study. Means was, among other things, a Methodist minister, an inventor, a physician, and a poet.
Born in Statesville, North Carolina, in 1801, Means began his career as a school teacher in Georgia. His curiosity later took him into medicine, electronics, and ministry. At age twenty-four, he went to Transylvania University in Kentucky, where he studied medicine for a year. Soon after, while practicing medicine in Covington, Georgia, he was granted a local preacher's license by the Methodist Episcopal Church.
The three great interests in Means's life were science, religion and education, and he found that the first two came together naturally in the third. In 1834, the Georgia Conference chose Means as the first superintendent the Manual Labor School, a vocational school of the day. Means served until 1838, when he resigned to become professor of natural sciences in Emory College in its first year of instruction.
Traveling in England in 1851, Means became acquainted with the experiments of Michael Faraday, and on his return to Oxford he exhibited in his Emory laboratory what many regard as the first electric light in America. Considered more imaginative than inventive, it is said that Means predicted the phonograph and the electric engine two decades before their invention.
Ever energetic, Means willfully kept a torturous schedule from 1841 to 1858. Although he held the sciences chair at Emory College from 1838 until his resignation of the presidency in 1855, he was granted permission simultaneously to lecture in chemistry during the winter terms at Augusta Medical College from 1841 to 1858, and in 1853 he was elected president of the Southern Masonic Female College in Covington, a position he resigned the following year to accept the presidency of Emory. Always looking for new opportunities, Means proposed in 1855 that Emory should assume the property and charter of Oglethorpe Medical College, then a school of Oglethorpe University, and manage it as one of Emory's departments. The Emory trustees respectfully but firmly declined.
After serving as president of Emory for one semester, the board reluctantly granted permission for Means to accept a professorship in the Atlanta Medical College. A year later, a dissatisfied board convinced the distracted Means to resign the presidency, effective December 1855. Still, Means continued to alternate his teaching between the medical colleges in Atlanta, during the summer, and Augusta, during the winter. His later career continued to be distinguished by scientific work, and he was eventually elected a member of the American Association for the Advancement of Science. In 1883, at the age of eighty-three, Means died in Oxford and was buried there.
What drove Alexander Means so vigorously? What gave him the inspiration, the will to get up every morning and discover and solve? Could it possibly be a joy, an awe, a reverence in his heart which he captured in a few lines of text that he wrote while in his thirties? These words, attributed to Means, were set to music and first published in 1835 in William Walker's collection, The Southern Harmony and Musical Companion.
Words attributed to Alexander Means (1801 – 1883)
What wondrous love is this, O my soul, O my soul!
What wondrous love is this, O my soul!
What wondrous love is this that caused the Lord of bliss
To bear the dreadful curse for my soul, for my soul,
To bear the dreadful curse for my soul.
When I was sinking down, sinking down, sinking down,
When I was sinking down, sinking down,
When I was sinking down beneath God’s righteous frown,
Christ laid aside His crown for my soul, for my soul,
Christ laid aside His crown for my soul.
To God and to the Lamb, I will sing, I will sing;
To God and to the Lamb, I will sing.
To God and to the Lamb Who is the great “I Am”;
While millions join the theme, I will sing, I will sing;
While millions join the theme, I will sing.
And when from death I’m free, I’ll sing on, I’ll sing on;
And when from death I’m free, I’ll sing on.
And when from death I’m free, I’ll sing and joyful be;
And through eternity, I’ll sing on, I’ll sing on;
And through eternity, I’ll sing on.
"Presidents - Alexander Means, 1801 - 1883." The History of Emory University. Ed. Office of the Deputy to the President. Emory University, 11 Oct. 2007. Web. 22 Sept. 2009. <http://emoryhistory.emory.edu/people/presidents/Means.htm>.
"What Wondrous Love Is This?" NetHymnal. 4 Oct. 2007. Web. 22 Sept. 2009. <http://www.cyberhymnal.org/htm/w/h/a/whatwond.htm>.
"Wondrous Love, 252 of Southern Harmony." Christian Classics Ethereal Library. Calvin College. Web. 22 Sept. 2009. <http://www.ccel.org/ccel/walker/harmony/files/hymn/Wondrous_Love.html>.
Monday, September 21, 2009
On September 16, the European Southern Observatory (ESO) announced they had the first solid evidence of a rocky exoplanet. I can hear your queries. Firstly, you ask, what is an exoplanet. And secondly, I hear, why would it be rocky?
First, an exoplanet, also called an extrasolar planet, is a planet located beyond our Solar System, orbiting a star other than our Sun. As of September 17, 2009, there were 374 exoplanets listed in the Extrasolar Planets Encyclopaedia (http://exoplanet.eu/). Yes, there are now so many of them that they have their own encyclopaedia. How do astronomers find exoplanets? They mostly use indirect methods, seeing how orbiting planets affect--wobble--the movement their parent stars. This process of detection is called radial velocity observation. The process is complex and requires lots of measurements before astronomers are satisfied with the findings and actually announce the existence of an exoplanet. Most of the exoplanets announced to date are massive gas giant planets thought to resemble our Jupiter, but the size of the planets discovered to this point is biased because of the limitations of our technology in the detection process--the planets usually have to be relatively big in order to induce a noticeable wobble in their parent stars. Projections based on the recent detections of much smaller worlds suggest that lightweight, terrestrial-type planets, or “rocky” planets as they are sometimes described, will eventually be found to outnumber extrasolar gas giants. These rocky planets would be similar in composition to our Mercury, Venus, Earth, and Mars. And this takes care of question number two.
The September 16 announcement by the ESO is in reference to CoRoT-7b, a planet orbiting the orange dwarf star CoRoT-7 (previously cataloged as TYC 4799-1733-1). The star CoRoT-7 is located in the direction of the constellation Monoceros (the Unicorn), five hundred light-years away. The star is slightly smaller and cooler than our Sun, and is also thought to be younger, with an age of about 1.5 billion years. The existence of exoplanet CoRoT-7b was first announced February 9 after about a year of observations and measurements. What makes CoRoT-7b so remarkable is that it was detected by direct observation, when it passed in front of its parent star and caused a noticeable dimming of the star's light. The difference in brightness, combined with a size estimate for the parent star, allowed astronomers to calculate the planet's size. It turns out that CoRoT-7b is the smallest and fastest-orbiting exoplanet discovered so far, with a blistering orbital period of 20.4 hours. That velocity--more than 750,000 kilometers per hour--puts the planet only 2.5 million kilometers away from its parent star, or 23 times closer than Mercury is to the Sun.
The latest observations were made using the High Accuracy Radial velocity Planet Searcher (HARPS) instrument attached to the ESO 3.6-m telescope at La Silla Observatory in Chile. The HARPS measurements were the longest made on a start to date. They reveal the planet's mass to be five times that of Earth's. Combined with CoRoT-7b's known radius, which is less than twice that of Earth, this tells astronomers that the exoplanet's density is very similar to the Earth's, suggesting a solid, rocky world. Because of the relative size and mass of planets such as this, they are described as “super-Earths.” And what’s more, the extensive observation also found another wobble that indicates the presence of another super-Earth in this alien solar system.
About a dozen super-Earths have been detected, though in the case of CoRoT-7b, this is the first time that the density has been measured for such a small exoplanet. We owe this to the fact that, from our perspective, CoRoT-7b transits--passes in front of--its parent star on every orbit.
For more details on these discoveries, and to learn more about the European Southern Observatory, check out their home page: http://www.eso.org/
Sunday, September 20, 2009
Were you ever certain you should do something, but did not know why? Did you act on your feeling, question it, or ignore it? The Apostle Philip was successfully ministering in the city of Samaria. The people were listening. Unclean spirits were being cast out. The paralyzed were healed. People were turning from their old lives and being baptized. And there was much joy in the city. But God had new plans for Philip. God told Philip to leave Samaria and go into the desert. Whatever Philip thought about this change, he obeyed.
An angel of the Lord led Philip to a barren place on the road from Jerusalem to Gaza. There Philip met an Ethiopian eunuch—an official who served as treasurer in the court Candace, the title for the queen of Ethiopia. The official had traveled to Jerusalem to worship and he was now on his way back home. When Philip saw the official’s chariot, the Holy Spirit told Philip to go near. Philip ran up, and heard the official reading out loud from the book of Isaiah. He asked the official, “Do you understand what you are reading?”
“How can I,” he answered, “unless someone explains it to me?” The official invited Philip to sit with him.
This was the passage he was reading.“He was led as a sheep to slaughter; and as a lamb before its shearer is silent, so he does not open his mouth. In humiliation his judgment was taken away; who will relate his generation? For his life is removed from the earth.”
The official asked whether Isaiah was speaking of himself or someone else. Philip took the opportunity and ran with it. Beginning with this Scripture passage he preached the good news of Jesus to him. This encounter was not a coincidence. The Holy Spirit’s activity is evident.
As the chariot passed water, the Ethiopian indicated his desire to be baptized. He understood and wanted to make a commitment. When they came out of the water, the Holy Spirit took Philip to witness elsewhere. The Ethiopian official continued heading south on his long journey home, rejoicing as he went.
Sometime, someplace, God will want you to share the biblical message of Jesus. It may be in someone’s home, in a store, in a gas station, or on an airplane. God may place you next to a person who needs to hear about Jesus. Will you be faithful to share your relationship with Christ?