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Astronomy From Your Back Yard - 5/5 to 5/11 2010

Week of May 5th Ė May 11th
By Dave Grosvold

Wednesday night, the Last Quarter Moon will occur at 11:16 PM CDT. Do you know the names of the Moon? “Moon” is a Germanic word, related to the Latin word mensis, which means month. However, the Latin name for the Moon was Luna, from which we get lunar, and lunatic. In Greek mythology, the Moon was known as Selēnē. The modern term selenology is a derivative, and it refers to the study of lunar science, including geology. The Moon is the fifth largest natural satellite in the Solar System, which makes it unique because Earth, the Moonís host planet, is only about 4 times as large as the Moon. The close Earth-Moon size relationship makes it almost a binary planet system rather than a planet-satellite system such as those found in the large outer planets.
Earthís sister planet Venus is low in the western sky in early evening, and will be setting by around 10:00 PM CDT. Venus may not be visible if your western horizon is blocked by trees or buildings.

Yellowish Saturn is high in the southeastern sky in the evening, this week, and will be visible all night. Reddish Mars also rides high in the southern sky in the evening, and will be visible all night as well. The Earth is slowly drawing farther away from both these planets as the year progresses, so they will be slightly dimmer each night as the year wanes. The dimming of these two wanderers would not necessarily be visible from night to night but it is noticeable when compared from month to month.

All this week, The Coma Cluster is visible above Virgo high in the southeastern sky. This is a beautiful open star cluster visible in 7X50 or 10x50 binoculars. Probably the best time for viewing this cluster is between 9:30 and 11:00 PM CDT on Thursday, Friday, or Saturday evenings. Donít forget to look for galaxies in the Virgo Cluster this week as well. See last weekís post for details on that.

According to most sources, the Eta Aquarid Meteor shower peaks on the morning of Thursday, May 6th. The best time for viewing will be between 3 and 5 AM CDT on the mornings of May 5th, 6th, and 7th. One of two meteor showers composed of dust particles from Halleyís Comet, every year the Eta Aquarids can be seen from as early as April 21 through about May 12. However, the number of meteors you are likely to see will be low until around the time of the peak on May 5/6. At their peak, Northern Hemisphere observers are likely to see about 10 meteors every hour. Unfortunately, since the waning crescent Moon is just past Last Quarter, the Moon will be in the south eastern sky in the early morning hours, and some of the fainter meteors may be rendered invisible due to resulting moonglow.

Look low in the eastern sky in the early morning on Sunday, May 9th for Jupiter rising below the crescent Moon. Also on Sunday morning, you can catch the Galilean Moons (the four largest moons of Jupiter,) in a small telescope or binoculars before dawn between 4:30 and 5:00 AM CDT. The International Space Station will make another pass low in the northern sky on Tuesday, May 11th. The ISS will rise in the North, becoming visible when it is 10° above the horizon, rise to 14° in the north-northeast, and then sink back to about 10° in the NNE before disappearing again. It will only reach about -0.7 magnitude this time.

There will be several Iridium Flares this week, mostly in the early morning hours, however the brightest will be in the evening on Sunday evening, May 9th. Look for Iridium 83 Sunday evening at 9:16 PM CDT high in the Eastern sky at an altitude of 58°. This flare will reach a brightest magnitude of -8 so it should be an easy catch. Check the web site at Heavens Above for other Iridium Flare times and locations.
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Astronomy From Your Back Yard - 4/28 to 5/4 2010

Week of April 28 to May 4, 2010
By Dave Grosvold

Wednesday, April 28th
The Moon is just past Full this evening, which occurred at 7:18 AM CDT. Tonight the Moon rises at 8:42 PM CDT, which washes out most of the eastern and southern skies. It is also too bright at or near Full to view through a telescope or binoculars, unless you have a filter. However, the Moon does look great when Full and viewed with the unaided eye.

One thing you can catch even with a Full Moon will be the brightest pass of the International Space Station (ISS) this week at -3.3 magnitude (Mag.) The ISS passes overhead starting at 9:18 PM CDT. It will swing from an altitude of 10° in the SW, up to 82° in the NW, then sink to 11° in the NE before becoming invisible. Look for the ISS to reach its brightest high overhead in the northwest.

Mars is also high overhead, but now dimming in Cancer as it pulls away from the Earth. Mars is still east of the Beehive Cluster. Jupiter is rising just before dawn in the eastern sky. At this time of the morning, Jupiter is brightest object in the sky.

Thursday, April 29th
Look to the lower left of the Moon tonight after 11 PM or so for rising Antares. Antares (an-TAR-eez) is a bright red supergiant star in Scorpius, with an approximately 800 times larger radius than our Sun. But Antares is a cool, low density star, with only about 18 solar masses, and it radiates most of its energy in the infrared part of the spectrum. Antares resides about 600 light years from our Solar System.

Catch the ISS again this evening at 8:44 PM CDT, starting at 10° in the S, going up to 24° in the SE, then back to 10° in ENE. It stays low in the sky this evening and shines a bit less bright at only -2.1 Mag.

Friday, April 30th
Many members of the Virgo Cluster of Galaxies can be spied in binoculars on a good dark, moonless night. This area in Virgo is home to a huge group of galaxies, which are part of our own Local Supercluster. Tonight you have a chance to see many of them before the Moon rises, just before 11:00 PM. Look for very faint fuzzy splotches slightly bigger than stars. Stars will always appear as a point source in binoculars or a telescope, but extended objects like galaxies and nebula will appear to be larger than points, sometimes much larger. In a medium amateur telescope (10” or so,) there are enough galaxies visible in this part of the sky to keep you busy most of the night.

On Friday evening, the ISS passes low in the north but brighter than the last one at -3.1 Mag, starting at 8:34 PM CDT, look for it at 10° in the NNW. It will be hard to spot this time since it won't get more than 10° above the horizon.

Saturday, May 1st
Venus is near the Pleiades low in the western sky all week. The Pleiades or M45, is a nearby region of recent star formation, and so is full of hot, young, blue-white stars.

On Saturday evening, look ¼° to the lower left of Venus in binoculars for Kappa Tauri — a binary star in Taurus. You should be able to discern both components of the binary pair in binoculars. Whether you realize it or not, most star systems are binary stars. As a single star, our Sun is an exception, not the norm.

Sunday, May 2nd
You can catch Iridium Flares on Sunday, Monday, and Tuesday evenings. On Sunday morning, Iridium 96 flares to -7 Mag at 6:04 AM CDT, Look for it at an altitude of 27°, in the north-northeast.

Monday, May 3rd
Saturn is high in the south at the head of Virgo all week. Look for fine black shadow of rings on disk of planet in telescope or binoculars.

On Monday evening, Iridium 56 flares to -8 Mag at 9:43 PM CDT. It should be visible at an altitude of 49° in the eastern sky. Remember, Iridium Flares are brief and not something that will be visible for more than a few seconds. The flare Monday night will be the brightest one visible this week.

Tuesday, May 4th
On Tuesday, you have two chances to see an Iridium Flare. In the morning, Iridium 29 flares to -3 Mag at 5:47 AM CDT, 21° high in the north-northeast. In the evening, Iridium 84 flares to -2 Mag at 9:37 PM CDT, at an altitude of 49° in the eastern sky.
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A Rock Hound is Born

NASA Space Place
Opportunity spots a rock with its NavCam that its AEGIS software says meets all the criteria for further investigation.
Click for larger view.
Itís tough to be a geologist when you canít tell one rock from another. Is that a meteorite or a chunk of lava? A river rock or an impact fragment? Houston, we have a problem!

Itís a problem Spirit and Opportunity have been dealing with for the past six years. The two rovers are on a mission to explore the geology of the Red Planet, yet for the longest time they couldnít recognize interesting rocks without help from humans back on Earth.

Fortunately, it is possible to teach old rovers new tricks. All you have to do is change their programmingóand thatís just what NASA has done.

“During the winter, we uploaded new software to Opportunity,” says Tara Estlin, a rover driver, senior member of JPLís Artificial Intelligence Group, and the lead developer of AEGIS, short for Autonomous Exploration for Gathering Increased Science. “AEGIS allows the rover to make some decisions on its own.”

Estlin and her team have been working for several years to develop and upload increasingly sophisticated software to the rovers. As a result, the twins have learned to avoid obstacles, identify dust devils, and calculate the distance to reach their arms to a rock. With the latest upgrade, a rock hound is born.

Now, Opportunity's computer can examine images that the rover takes using its wide-angle navigation camera (NavCam) and pick out rocks with interesting colors or shapes. It can then center its narrower-angle panoramic camera (PanCam) on targets of interest for close-up shots through various color filters. All this happens without human intervention.

The system was recently put to the test; Opportunity performed splendidly.

At the end of a drive on March 4th, the rover settled in for a bit of rock hunting. Opportunity surveyed the landscape and decided that one particular rock, out of more than 50 in the NavCam photo, best met criteria that researchers had set for a target of interest: large and dark. “It found exactly the target we would want it to find,” Estlin says. “It appears to be one of the rocks tossed outward onto the surface when an impact dug a nearby crater.”

The new software doesnít make humans obsolete. On the contrary, humans are very much “in the loop,” setting criteria for whatís interesting and evaluating Opportunityís discoveries. The main effect of the new software is to strengthen the rover-human partnership and boost their combined exploring prowess.

Mindful that Opportunity was only supposed to last about six months after it landed in 2004, Estlin says “it is amazing to see Opportunity performing a brand new autonomous activity six years later.”

What will the rock hounds of Mars be up to six years from now? Stay tuned for future uploads!

Learn more about how the AEGIS software works at http://scienceandtechnology.jpl.nasa.gov/newsandevents/newsdetails/?NewsID=677. If you work with middle- or high-school kids, youíll find a fun way to explore another kind of robot softwareóthe kind that enables “fuzzy thinking”óat http://spaceplace.nasa.gov/en/educators/teachers_page2.shtml#fuzzy.

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
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The Big Dipper and the Lyrids

Click image for larger view
This time of year, the Big Dipper rides high in the northeastern sky in the evenings, tilted back so the “water” runs out and appears to fill the bowl of the Little Dipper. The Big Dipper and Little Dipper are asterisms found in the constellations of Ursa Major, the Great Bear, and Ursa Minor, the Lesser Bear, respectively. An asterism is a highly recognizable pattern in the night sky that is not one of the 88 constellations designated by the International Astronomical Union (IAU). Although the pattern may wholly reside in a single constellation, often times it does not. An asterism may even be what we recognize as a constellation, as is the case with the Big Dipper, which is what we normally think of when we look for the constellation Ursa Major. As mentioned in a previous column, the “pouring out” of the Big Dipper is typically associated with the coming of spring rains.

Although the Lyrids are common throughout the month of April, this week is the best time to view this meteor shower. Astronomers expect this lesser-known shower to be active Thursday and Friday morning in the hour or so before dawn, just after the Moon sets. The Lyrids are typically weak, but are known for occasional outbursts and sometimes even large bolides (fireballs,) like the one that occurred in the northern sky on April 10th.
The April 10th fireball was visible from Fort Smith and all over NW Arkansas. All of the meteors in this shower appear to come from somewhere in the constellation Lyra, which is home to the bright star Vega. Vega was popularized as the source of alien signals in the 1997 movie Contact, based on Carl Saganís book by the same name.

The latter half of this week will also be a great time to observe the Moon, which passed First Quarter at 1:20 PM CDT on Wednesday April 21st. Using a small telescope or binoculars reveals a myriad of craters and other lunar features. Pay special attention to the terminator, which is the line of demarcation between the lit portion of the Moon and the dark side. Here, you will find the best contrast which in turn enables you to see the smallest details.
Click image for larger view
On Thursday evening, April 22nd, the Moon will be in a very nice tight grouping with Mars, the Beehive Cluster (also known as Praesepe or M44,) the bright asteroid Vesta, and Regulus. Regulus is the bright star at the end of the handle in the Sickle of Leo, another well-known asterism. Look below the Moon on Thursday evening for the orange-red star Alphard, the heart of Hydra, the Water Snake.

On Friday evening, April 23rd, Venus and the Pleiades (pronounced PLEE-a-deez, also known as the Seven Sisters or M45,) will be within the 5° of a single field of view in binoculars. Look for them low in the west just after sunset.

The International Space Station (ISS) will pass overhead several times over the next few days, but the two brightest passes will be on Monday and Tuesday mornings at 5:33 AM and 5:57 AM, respectively. In both cases, the ISS will begin rising in the NW. On Monday, April 26th the ISS will reach maximum altitude of 67° in the NE, at a magnitude of -3.0. On Tuesday, April 27th, it will only reach 27° in the SW at a magnitude of -2.3. You can find out more detail about when the ISS will be overhead at http://www.heavens-above.com.
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Deadly Planets

NASA Space PlaceBy Patrick L. Barry and Dr. Tony Phillips

Artistís concept of a pulsar and surrounding disk of rubble called a “fallback” disk, out of which new planets could form.
Click for larger view.
About 900 light years from here is a rocky planet not much bigger than Earth. It goes around its star once every hundred days, a trifle fast, but not too different from a standard Earth-year. At least two and possibly three other planets circle the same star, forming a complete solar system.

Interested? Don't be. Going there would be the last thing you ever do.

The star is a pulsar, PSR 1257+12, the seething-hot core of a supernova that exploded millions of years ago. Its planets are bathed not in gentle, life-giving sunshine but instead a blistering torrent of X-rays and high-energy particles.

“It would be like trying to live next to Chernobyl,” says Charles Beichman, a scientist at JPL and director of the Michelson Science Center at Caltech.

Our own Sun emits small amounts of pulsar-like X-rays and high energy particles, but the amount of such radiation coming from a pulsar is “orders of magnitude more,” he says. Even for a planet orbiting as far out as the Earth, this radiation could blow away the planet's atmosphere, and even vaporize sand right off the planet's surface.

Astronomer Alex Wolszczan discovered planets around PSR 1257+12 in the 1990s using Puerto Ricoís giant Arecibo radio telescope. At first, no one believed worlds could form around pulsars — it was too bizarre. Supernovas were supposed to destroy planets, not create them. Where did these worlds come from?

NASAís Spitzer Space Telescope may have found the solution. In 2005, a group of astronomers led by Deepto Chakrabarty of MIT pointed the infrared telescope toward pulsar 4U 0142+61. Data revealed a disk of gas and dust surrounding the central star, probably wreckage from the supernova. It was just the sort of disk that could coalesce to form planets!

As deadly as pulsar planets are, they might also be hauntingly beautiful. The vaporized matter rising from the planets' surfaces could be ionized by the incoming radiation, creating colorful auroras across the sky. And though the pulsar would only appear as a tiny dot in the sky (the pulsar itself is only 20-40 km across), it would be enshrouded in a hazy glow of light emitted by radiation particles as they curve in the pulsar's strong magnetic field.

Wasted beauty? Maybe. Beichman points out the positive: “It's an awful place to try and form planets, but if you can do it†there, you can do it anywhere.”

Find more news and images from Spitzer at http://www.spitzer.caltech.edu/. In addition, The Space Place Web site features several games related to Spitzer and infrared astronomy, as well as a storybook about a girl who dreamed of finding another Earth. Go to http://tiny.cc/lucy208.

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
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The Last Week of Winter

Figure 1. Looking NE, 9:00 PM March 13, 2010
By Dave Grosvold

This coming week is the last week of the Winter season in the northern hemisphere, and is marked by the appearance of fiery Arcturus (Ark-TUR-es) in the evening Eastern Sky. Arcturus (Alpha Boötis,) is by definition the brightest star in the constellation Boötes (pronounced Boh-OH-teez.) The Ancient Greek name Arcturus means “Guardian of the Bear,” and is appropo considering its proximity to Ursa Major and Ursa Minor, the Great and Small Bears. The orange giant star's celestial appearance was supposed to portend tempestuous weather in Ancient Greece, and that certainly seems true in our millennium as well! Looking northeast in the evenings this week, you will find the Big Dipper (part of Ursa Major) tipping back on its handle until the water spills out the back of the bowl, which is another ancient sign of stormy weather ahead.

Following the handle from the bowl in an arc along the handle stars will lead you to Arcturus (see Figure 1.) Arcturus, being the third brightest star in the sky after Sirius and Canopus is a mere 36.7 light years from Earth. This places it in the same vicinity in the Orion Arm of the Milky Way galaxy as Earth — a very close neighbor in astronomical terms.

Venus is very low in the southwest just after sunset this week, but will be rising higher and higher each evening. If you look carefully, you might just find the thinnest sliver of the New Moon below and to the right of Venus during the last of the sunset on Tuesday, March 16th. By Wednesday, the now-visible waxing crescent Moon will be higher than Venus in the west-southwest.

Figure 2. Looking southwest just after sunset on Wednesday, March 17, 2010
Saturn is getting higher in the night sky this week and is nearing opposition, which falls on March 21 this year. Look for Saturn low in the east after sunset, higher in the southeast in late evening, and at its highest in the south at 1:00 AM this week. The rings are tilted nearly edge-on now, and will reach their most edge-on position in May.

Mercury is hidden in the glare of the Sun. Jupiter is now rising as a morning star, but hidden deep in the surrounding glow of the Solar disk. Uranus and Neptune are also both hidden in the glare of the Sun.

The Spring Equinox occurs at 12:32 PM Central Daylight Time on Saturday, March 20, and marks the beginning of Spring in the Northern Hemisphere. That evening, we will see a special treat. The Moon will be right next to the Pleiades (PLEE-a-deez) that evening, and will present a spectacular sight — especially in binoculars! The Moon will be so close that it will occult some of the fainter outlying stars of the Pleiades cluster.

An occultation is the covering of one celestial object by another as the first object passes in front of the second. The best observing time for this is 9:00 or 9:30 PM on Saturday, March 20th. Be sure to mark your calendar! This event will be the last occultation of the Pleiades by the Moon visible from North America until 2023.

Figure 3. Looking SW, 9:00 PM, Saturday, March 20 2010
The International Space Station will not be visible this week, but there will be a couple of bright Iridium Flares, if the weather cooperates. We have a shot at a VERY bright one (mag -8.0) at 6:23 AM on Sunday morning, March 14th, when Iridium 72 passes nearly directly overhead. Look directly North at an altitude of 46¬į to catch this flare.

Another bright Iridium Flare will occur early on Friday evening at 7:53 PM. Iridium 25 will only reach magnitude -2.0, and will be visible in the south-southeast at an altitude of 49¬į above the horizon. You might also want to try to catch Iridium 62 at 6:17 AM on Monday, March 13th in the North at an altitude of 44¬į, or Iridium 22 at 7:59 PM on Thursday, March 18th in the SSE at an altitude of 47. These two flares will only reach magnitude -0.0 and -1.0, respectively.
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The Hunter and His Faithful Dogs

By Dave Grosvold

Orion the Hunter will be at its highest point in the evening sky this month. By late March, you will notice him sliding back down toward the western horizon, just a bit lower at the same time each successive evening. Orange super-giant Betelgeuse (BEE-tel-joos) at Orion's upper left shoulder forms one apex of the Winter Triangle, with Procyon (PRO-see-yon) and blue-white Sirius forming the other two. Procyon and Sirius are the brightest stars in the two constellations that represent Orionís faithful hunting dogs, Canis Minor, and Canis Major, respectively.

On the Apparent Magnitude scale, the higher the number, the dimmer the object, so Procyon, which is Magnitude 0.45, is dimmer than Sirius, at Magnitude -1.45. Sirius is considered the brightest star in the night sky. Venus is much brighter, at Mag -3.80.

The International Space Station (ISS) and Iridium Flares can both be brighter than Sirius, and sometimes even brighter than Venus. This week, the ISS will be almost as bright as Venus on Wednesday morning (Mag -2.9), when it passes overhead at 6:00 AM, swinging from an altitude of 20° in the WNW, up to about 43° in the SW and then back down to 10° in the SSE.

There will be four Iridium Flares visible this week, on Thursday and Friday evenings, and also Friday and Saturday mornings. These flares will be approximately Mag -2.0, so they will be brighter than Sirius in the evening and pre-dawn skies. Look for them in the south at 6:58 PM on Feb 25 (Iridium 66), and 6:52 PM on Feb 26th (Iridium 21), at an altitude of 48°. The flares will also be visible in the south at 5:35 AM on Feb 26th (Iridium 18), and 5:29 AM on Feb 27th (Iridium 39), this time at an altitude of 39° above the horizon.

The Moon entered First Quarter on Sunday, Feb 21st, so it will be waxing gibbous all week, reaching Full Moon by Sunday, Feb 28th. It will be high in the sky by 8:00 PM on Monday evening, and will then be lower in the east each successive evening. Look for the Moon between Castor and Pollux, the twins of Gemini at 8:00 PM on the 24th.

By the 25th, the Moon passes within 5° of Mars, and by the 27th the bright nearly full Moon will be only 4° below Regulus, the front shoulder of Leo. Remember, the width of your index finger held at armís length is about 1.5°, so three fingers would be about 4.5°.

Fiery Mars is past opposition now, so it wonít be as bright as it was last month, but itís still a great target in a small telescope. Mars rides high in the sky this week, in a line below the twins of Gemini, about halfway between them and M44, the Beehive Cluster. Look for Mars in the eastern sky at 8:00 PM.

Saturn will be rising in the East just before 8:00 PM on the 27th. You can catch Saturnís largest moon, Titan at about the 1:30 position in a pair of binoculars or a small telescope anytime after 8:30 PM. Remember that most telescopes either invert the image or mirror it, so you might have to look at the 7:30 or 10:30 position in your scope, unless you have an erect-image prism in the optical train.

The bright asteroid Vesta, is just past opposition and still at magnitude 6.1. Vesa continues its travels across the Sickle of Leo, as shown in the last image. You should be able to spot it in binoculars.
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Apple iPhone/iPod Astronomy Apps

Computers & Software

I recently purchased a 3rd Generation 64 Gigabyte Apple iPod Touch. The original intent was to use it to listen to Music (MP3s), watch movies, and access the internet on the go.

Basically, an iPod Touch and most of the other “Smart Phones” are miniature computers. Most use a Flash Hard Drive for storage and have rechargeable lithium batteries.

Smart Phones, such as the Apple iPhone or the Motorola Droid can access the Internet via a 3G network, which works the same way as making a Cell Phone call, i.e., the internet data is sent and received via a cell phone signal to the nearest cell tower.

Other devices, such as the Ipod Touch are not cell phones, but can access the internet through a WIFI network connection, just like a desktop or a laptop computer in your home, a coffee shop or an airport.

Apple developed the iTunes Store website to sell music, movies and software to iPhone and iPod owners.

Apple and independent computer programmers write software applications (Apps) that will do about anything imaginable. These Apps are usually very cheap, not more that a couple of bucks, or free to download. If you can think of something that you want your Apple device to do, most likely, “There Is An App For That”, including Astronomy.

The following are a few Astronomy Apps that I have found in the Apple iTunes Store that are very useful and of very high quality:

Sky Voyager: This is a very good Planetarium program that very accurately shows the locations of Deep Sky Objects, planets, the moon, stars and constellations, very similar to “Stellarium” or other planetarium software programs for computers. This App will also show the brighter comets and asteroids and identify and plot passing artificial satellites.

Pocket Sat 3: This is a free App that will predict the passage, or identify artificial satellites as the pass overhead. The orbits are projected on a image of the constellations in the night sky in real time. This App will let you know when a Satellite such as the International Space Station will appear overhead up to a year in advance. How many times have you been out at night, and wondered what that bright, moving light was. This App will tell you.

Iridium Flares: This free App will predict when, where, and how bright Iridium Flares will occur.

Moon Globe: Very similar to “The Virtual Moon Globe”, this App will help you identify or locate lunar features with a “3D Photo Quality” map.

Mars Globe: Very similar to Moon Globe, this App is for Mars, based on NASA spacecraft photos, with a “3D Photo Quality” map.

NASA App: This App takes data from NASA's Internet Website via a WIFI Connection and gives you instant access to the latest NASA News, Photos and Videos.

These are just a few of the Astronomy Apps that are available at the Apple iTune Store. New ones are added from one day to the next.

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Flipping the Lights on Cosmic Darkness

NASA Space Place
The Herschel Space Observatory has 3.5-meter primary mirror, allowing astronomers to see colder, darker celestial objects than ever before.

Click image for larger view.
Exploring the universe is a bit like groping around a dark room. Aside from the occasional pinprick of starlight, most objects lurk in pitch darkness. But with the recent launch of the largest-ever infrared space telescope, it's like someone walked into the room and flipped on the lights.

Suddenly, those dark spaces between stars donít appear quite so empty. Reflected in the Herschel Space Observatory's 3.5-meter primary mirror, astronomers can now see colder, darker celestial objects than ever before — from the faint outer arms of distant galaxies to the stealthy “dark asteroids” of our own solar system.

Many celestial objects are too cold to emit visible light, but they do shine at much longer infrared wavelengths. And Herschel can observe much longer infrared wavelengths than any space telescope before (up to 672 microns). Herschel also has 16 times the collecting area, and hence 16 times better resolution, than previous infrared space telescopes. That lets it resolve details with unprecedented clarity. Together, these abilities open a new window onto the universe.

“The sky looks much more crowded when you look in infrared wavelengths,” says George Helou, director of the NASA Herschel Science Center at Caltech. “We can't observe the infrared universe from the ground because our atmosphere blocks infrared light, and emits infrared itself. Once you get above the atmosphere, all of this goes away and suddenly you can look without obstruction.”

Herschel launched in May from the Guiana Space Centre in French Guiana aboard a European Space Agency Ariane 5 rocket. Since then, it has expanded the number of distant galaxies observed at far infrared wavelengths from a few hundred to more than 28,000. And with the instrument testing and system check-out phases finally completed, the discoveries are only now beginning.

Beyond simply imaging these dark objects, Herschel can identify the presence of chemicals such as carbon monoxide and water based on their spectral fingerprints. “We will be able to decipher the chemistry of what's going on during the beginnings of star formation, in the discs of dust and gas that form planets, and in the lingering aftermath of stellar explosions,” Helou says.

And those are just the expected things. Who knows what unexpected discoveries may come from “flipping on the lights?” Helou says “we can't wait to find out.”

Herschel is a European Space Agency mission, with science instruments provided by a consortium of European-led institutes and with important participation by NASA. See the ESA Herschel site at sci.esa.int/science-e/www/area/index.cfm?fareaid=16. Also, see the NASA sites at herschel.jpl.nasa.gov, www.herschel.caltech.edu, and www.nasa.gov/mission_pages/herschel. Kids can learn about infrared light by browsing through the Infrared Photo Album at The Space Place, spaceplace.nasa.gov/en/kids/sirtf1/sirtf_action.shtml.

This article was provided courtesy of the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
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What's New On (Or Under) The Sun?

Images from EIT at 195 and 304 angstroms, MDI Magnetogram, and LASCO C3.
Virtual Moon Atlas
Carte Du Ciel
Stellarium
By Dave Grosvold

In the dark and gloomy days of winter, is there still a way to engage in observational astronomy? Did you know you can observe the Sun when itís cloudy? Did you know you can observe the entire night sky in the daytime? What about observing the Moon when itís not visible in the night sky? These are all possible with some help from your computer and the Internet.

Observing The Sun

The Solar and Heliospheric Observatory web site provides images of the Sun in many different forms. All of these images are taken every few minutes, so you can follow activity on the Sun in near-real time. Images from the Extreme ultraviolet Imaging Telescope (EIT) are taken in several different wavelengths of ultraviolet light (304, 171, 284, and 195 angstroms). These wavelengths correspond to different surface temperatures on the Sun, from 60,000 degrees Kelvin to over 2 million degrees Kelvin. The hotter the temperature, the higher in the solar atmosphere we see.

The Michelson Doppler Imager (MDI) captures data that provides us with a view of current sunspot activity, such as this magnetogram image. The Large Angle Spectrometric Coronagraph captures activity in the solar corona by blocking out the overwhelming light from the Sun itself so the delicate corona can be seen. This allows us to see streamers and radial bands in the corona that would otherwise be invisible. Visit SOHO Explore! to learn more about the Sun and how it works.

Virtual Moon Atlas

Want to observe the Moon? The Virtual Moon Atlas is a free software download available for Windows, Mac, and Linux PCs that allows you to view very high resolution photographs of the entire surface of the Moon. There are thousands of identifiable features and a huge amount of detailed information, including multiple scientific overlays, including rock types, presence of certain trace elements, altitudes, surface temperature, iron oxides, etc.

The program is available in over a dozen languages, with complete documentation, quick star guides, and a multitude of downloadable add-ons including textures and picture libraries. PocketLun, the Pocket PC version of VMA is even available for Windows Mobile devices. VMA is a professional-level program and will provide even the advanced the Lunar Observer with hours of observational study.

Charts and Planetariums

There are a number of free sky chart programs on the market. The most notable is Carte Du Ciel (literally ďSky ChartsĒ,) by Patrick Chevalley, the author of Virtual Moon Atlas mentioned above. Carte Du Ciel (CDC) has as many databases available as many of the expensive commercial offerings, and charts can be printed to great detail - as deep as most, if not all, printed star atlases. Many amateur astronomers use CDC as their software tool of choice when it comes to controlling a telescope in conjunction with their astroimaging equipment.

There are also planetarium programs free for the download, such as Stellarium. Stellarium displays the night sky much as it would look to a naked-eye observer out under the stars. This includes such things as light pollution, fog, meteors, and the effects of the full moon and sun in the sky. Stellarium can be used as a basic charting program, but printing charts is not it's forte. It's much more at home displaying the night sky in a realistic way. Stellarium has a planetarium projection mode that can be used with an appropriate projector to display the entie night sky form horizon to horizon in a dome. See their web site for more information.

Both of these programs are great tools and would be welcome in any amateur astronomerís kit.

WorldWide Telescope

On a cold gloomy night in January, though, the best way to view the heavens is with WorldWide Telescope. WWT is a free product from Microsoft Research, and is available in the form of a Web Client for Mac, or as a download for Windows, that basically turns your computer into a Virtual Telescope. WWT brings together images from some of the worldís largest ground and space-based telescopes in a way that allows you to explore the universe in a seamless virtual environment.

WWT view of Jupiter
The images are breathtaking, and WWT provides a large number of guided tours that allow you to travel on a exploratory journey along with various astronomers from famous observatories and universities. See how dust in the Milky Way condenses into stars and planets! Travel 2 billion years into the past and learn how gravitational lensing works!

So you canít get outside and see the night sky? Observe anyway, using these fantastic tools and the Internet!

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