Let’s Study Law: Kepler Would Be So Proud!

Mars and Saturn Meet - Shevill Mathers

Just a couple of days ago we took a look at the splendid conjunction of Mars, Saturn and Regulus which occurred on July 6, 2008. Now, four days later, the position of everything has changed drastically. We watch it occur in the sky. We accept that it’s natural. We even know it’s celestial mechanics! But exactly what laws govern these movements and how do we understand them? Let’s take a look…

Johannes KeplerOnce upon a time, a very cool dude named Johannes Kepler was born just two days after Christmas in 1571. Like most of us, he had a pretty rough life. His dad died when he was 5, but he had a great mom who was not only a waitress, but a herbalist as well. One of the best things she ever did for her son was to take him out to watch the “Great Comet of 1577” and a lunar eclipse in 1580. Even though she ended up being later tried for witchcraft, the love of astronomy that she inspired in her son would shape the way we now understand planetary motion.

Even though smallpox crippled Kepler’s vision and hands, he excelled at studying planetary motion in the astrological sense and kept himself busy being a math teacher. In his spare time, he also liked to play around with lenses, too… and write letters to his friend Galileo Galilei. Even though he ran the risk of losing his job and getting in trouble with the church, Kepler defended Copernican theory of a sun-centered system and went on to devise some formulae of his own. At age 24, he was teaching a class about the conjunction of Saturn and Jupiter when he realized that regular polygons bound one inscribed and one circumscribed circle at definite ratios, which, he reasoned, might be the geometrical basis of the universe. Thankfully, his school supported him and published his work as the “Mysterium Cosmographicum” (The Cosmographic Mystery).

Fortunately, that was a good move and it landed Kepler a part time job helping out an astronomer named Tycho Brahe. To make a long story short, that was his introduction into the real world of astronomy and many long years and bad political times kept things from progressing. However, the astronomers of the time respected his work in their own ways and continued to test out Kepler’s theories – right down to his predictions when Venus and Mercury would transit the Sun. Yep. It would be long after Kepler died before his ideas were finally recognized, but these three principles withstood the test of time:

Kepler's Laws

1. The orbit of every planet is an ellipse with the sun at one of the foci.

2. A line joining a planet and the sun sweeps out equal areas during equal intervals of time. (Suppose a planet takes one day to travel from point A to B. The lines from the Sun to A and B, together with the planet orbit, will define a (roughly triangular) area. This same amount of area will be formed every day regardless of where in its orbit the planet is. This means that the planet moves faster when it is closer to the Sun.) This is because the sun’s gravity accelerates the planet as it falls toward the Sun, and decelerates it on the way back out, but Kepler did not know that reason.

3. The squares of the orbital periods of planets are directly proportional to the cubes of the semi-major axis of the orbits. Thus, not only does the length of the orbit increase with distance, the orbital speed decreases, so that the increase of the orbital period is more than proportional.

So what does studying these laws have to do with what we see? Let’s take a three day time lapse look…

Planetary Motion - July7-9, 2008 - Shevill Mathers

The observable distance between Saturn and Regulus hasn’t changed much has it? But the motion of Mars has been huge! When skies permit, make your own nightly observations of planetary motions and try studying Kepler’s law. We’ve watched Mars travel from points A to B. If we drew an imaginary line, from the Sun to the planet, it would sweep out a roughly triangular area and the same amount of area will be swept every day. As Mars progresses in its elliptical orbit, its distance from the Sun changes. As an equal area is swept during any period of time and the distance from Mars to the Sun varies, we can then plainly see that for the changes to remain constant that Mars must also vary in speed! Yep. It’s the second law.

Kepler would be so proud…

Many thanks to AORAIA member Shevill Mathers whose dedication and photographs helped make this article possible!

WeekEnd SkyWatcher’s Forecast: July 4 – 6, 2008

Artist Impression of Deep Impact - Credit: NASA

Greetings, fellow SkyWatchers! If you’re enjoying a holiday weekend where you live, then start the fireworks off as we begin by remembering Deep Impact and journey towards a nearby star approaching the supernova phase. As things heat up towards one of the most spectacular conjunctions of the year, we’ll also take a look at another globular cluster study, lunar features and a binocular deep sky treat! Are you ready to step in the realm of a Barnard dark nebula? The grab your optics and let’s head out into the night…

Friday, July 4 – On this date in 2005, the Deep Impact mission entered the history books as its probe impacted Comet Tempel 1 successfully. The spacecraft relayed back to Earth a wealth of information about the material released from the surface. Thanks to this incredible mission (a collaboration between JPL, the University of Maryland, and Ball Aerospace Technologies), we’ve learned much more about the nature of comets and the protosolar nebula in which they formed.

This date in history also marks the 1947 founding of the Astronomical League – a worldwide organization with almost 15,000 members!

And did you know that celestial fireworks occurred in 1054, also on this day? It is believed the bright supernova recorded by Chinese astronomers happened at this point in history, and today we know its remnants as the Crab Nebula (M1).

Palomar Observatory, courtesy of CaltechBut could such an event happen again in our own celestial “backyard?” Look no further than HR 8210 (RA 21 26 26 Dec +19 22 32). It may be nothing more than a white dwarf star hiding out in late night Capricornus, but it’s a star that’s almost run out of fuel. This rather ordinary binary system has a companion white dwarf star that’s 1.15 times the mass of our Sun. As the companion also expends its fuel, it will add mass to HR 8210 and push it over the Chandrasekhar limit – the point of no return in mass. This will someday result in a supernova event located only 150 light-years away from our solar system…

And that’s 50 light-years too close for comfort!

470 light-years away in the Gould Belt, and roughly 1.5 million years ago, a similarly massive star exploded in the Upper Scorpius association. No longer able to fuel its mass, it unleashed a supernova event which left its evidence as a layer of iron here on Earth, and may have caused a certain amount of biological extinction when its gamma rays directly affected our ozone layer.

Take a long look at Antares tonight – for it is part of that association of stars and is no doubt also a star poised on the edge of extinction. At a safe distance of 500 light-years, you’ll find this pulsating red variable equally fascinating to the eye as well as to the telescope. Unlike HD 8210, Alpha Scorpii also has a companion which can be revealed to small telescopes under steady conditions. Discovered on April 13, 1819 during a lunar occultation, this 6.5 magnitude green companion isn’t the easiest to split from such a bright primary – but it’s certainly fun to try! And the best is yet to come, because Antares will be occulted again in a matter of days…

Saturday, July 5– Tonight the Moon has returned in a position to favor a bit of study. Start by checking IOTA information for a possible visible occultation of Regulus, and also look for Saturn quite nearby as the slender crescent graces the early evening skies.

Although poor position makes study difficult during the first few lunar days, be sure to look for the ancient impact crater Vendelinus just slightly south of central. Spanning approximately 150 kilometers in diameter and with walls reaching up to 4400 meters in height, lava flow has long ago eradicated any interior features. Its old walls give mute testimony to later impact events, which you can see when viewing crater Holden on the south shore; much larger Lame on the northeast edge; and sharp Lohse northwest. Mark your challenge list!

For all observers, let’s take a closer look at the fascinating constellation of Lupus southwest of brilliant Antares. While more northern latitudes will see roughly half of this constellation, it sits well at this time of year for those in the south. So why bother?

Cutting through our Milky Way galaxy at a rough angle of about 18 degrees is a disc-shaped zone called Gould’s Belt. Lupus is part of this area whose perimeter contains star forming regions which came to life about 30 million years ago when a huge molecular cloud of dust and gas was compressed – much like in the Orion area. In Lupus we find Gould’s Belt extending above the plane of the Milky Way!

Palomar Observatory, courtesy of CaltechReturn again to the beautiful Theta and head around five degrees west for NGC 5986 (RA 15 46 03 Dec 37 47 10), a 7th magnitude globular cluster which can be spotted with binoculars with good conditions. While this Class VII cluster is not particularly dense, many of its individual stars can be resolved in a small telescope.

Now sweep the area north of NGC 5986 (RA 17 57 06 Dec 37 05 00) and tell me what you see. That’s right! Nothing. This is dark nebula B 288 – a cloud of dark, obscuring dust which blocks incoming starlight. Look carefully at the stars you can see and you’ll notice they appear quite red. Thanks to B 288, much of their emitted light is absorbed by this region, providing us with a pretty incredible on-the-edge view of something you can’t see – a Barnard dark nebula.

NASASunday, July 6 – Celestial scenery alert! SkyWatchers… Mark your calendar and be sure to make this date with the western skyline as sunset marks one of the most picturesque views of the year! Regulus, Mars and Saturn will all dance with the da Vinci Moon. No special equipment is needed to see this event, and thanks to Leonardo da Vinci we can see the ghostly effect on the Moon as quite logical. He was the first to theorize that sunlight was reflecting off the Earth and illuminating the portion of the Moon not lit by the Sun. We more commonly refer to this as “Earthshine” – but no matter how scientific the explanations are for this phenomena, its appearance remains beautiful.

Today in 1687, Isaac Newton’s monumental Principia was published by the Royal Society with the help of Edmund Halley. Although Newton was indeed a very strange man with a highly checkered history, one of the keys to Newton’s work with the theory of gravity was the idea that one body could attract another across the expanse of space.

Now let’s have a look at some things gravitationally bound as we start at Eta Lupi, a fine double star which can even be resolved with binoculars. Look for the 3rd magnitude primary and 8th magnitude secondary separated by a wide 15″. You’ll find it by starting at Antares and heading due south two binocular fields to center on bright H and N Scorpii – then one binocular field southwest (RA 16 00 07 Dec 38 23 48).

Palomar Observatory, courtesy of CaltechWhen you are done, hop another roughly five degrees southeast (RA 16 25 18 Dec 40 39 00) to encounter the fine open cluster NGC 6124. Discovered by Lacaille and known to him as object I.8, this 5th magnitude open cluster is also known as Dunlop 514, as well as Melotte 145 and Collinder 301. Situated about 19 light-years away, it will show as a fine, round, faint spray of stars to binoculars and be resolved into about 100 stellar members to larger telescopes. While NGC 6124 is on the low side for northern observers, it’s worth the wait for it to hit its best position. Be sure to mark your notes, because this delightful galactic cluster is a Caldwell object and a southern skies binocular reward!

Wishing you an awesome weekend…

This week’s photos are courtesy of: Deep Impact Mission – Credit: JPL/NASA, HR 8210 – Credit: Palomar Observatory courtesy of Caltech, NGC 5986 – Credit: Palomar Observatory courtesy of Caltech, Da Vinci Moon – Credit: NASA and NGC 6124 – Credit: Palomar Observatory courtesy of Caltech.

The Weekend SkyWatcher’s Forecast: June 27-29, 2008

Greetings, fellow SkyWatchers! It’s that time again and darker skies are in our favor for this weekend. Are you working towards Astronomical League studies? Then tag along as we seek out one of the most difficult of all targets – Palomar 5. But don’t despair – there’s just slightly easier ones to study, too! Come along for the double galaxy ride and the peak of two minor meteor showers as we head out into the night…

Friday, June 27 – As with all astronomical projects, there are sometimes difficult ones needed to complete certain fields of study – such as challenging globular clusters. Tonight we’ll take a look at one such cluster needed to complete your list and you’ll find it by using M5 as a guide.

Palomar Observatory, courtesy of CaltechPalomar 5 is by no stretch of the imagination easy. For those using GoTo systems and large telescopes, aiming is easy…but for star hoppers a bit of instruction goes a long way. Starting at M5 drop south for the double star 5 Serpentis and again south and slightly west for another, fainter double. Don’t confuse it with 6 Serpentis to the east. About half a degree west you’ll encounter an 8th magnitude star with 7th magnitude 4 Serpentis a half degree south. Continue south another half degree where you will discover a triangle of 9th magnitude stars with a southern one at the apex. This is home to Palomar 5 (RA 15 16 05 Dec 00 06 41).

Discovered by Walter Baade in 1950, this 11.7 magnitude, Class XII globular is anything but easy. At first it was believed to be a dwarf elliptical and possibly a member of our own Local Group of galaxies due to some resolution of its stars. Later studies showed Palomar 5 was indeed a globular cluster – but one in the process of being ripped apart by the tidal forces of the Milky Way.

75,000 light-years away from us and 60,000 light-years from the galactic center, Palomar 5’s members are escaping and leaving trails spanning as much as 13,000 light-years…a process which may have been ongoing for several billion years. Although it is of low surface brightness, even telescopes as small as 6″ can distinguish just a few individual members northwest of the 9th magnitude marker star – but even telescopes as large as 31″ fail to show much more than a faint sheen (under excellent conditions) with a handful of resolvable stars. Even though it may be one of the toughest you’ll ever tackle, be sure to take the time to make a quick sketch of the region to complete your studies. Good luck!

While you’re out, keep a watch for a handful of meteors originating near the constellation of Corvus. The Corvid meteor shower is not well documented, but you might spot as many as ten per hour.

Saturday, June 28 – Before you start hunting down the faint fuzzies and spend the rest of the night drooling on the Milky Way, let’s go globular and hunt up two very nice studies worthy of your time. Starting at Alpha Librae, head five degrees southeast for Tau, and yet another degree southeast for the splendid field of NGC 5897 (RA 15 17 24 Dec -21 00 36).

Palomar Observatory, courtesy of CaltechThis class XI globular might appear very faint to binoculars, but it definitely makes up for it in size and beauty of field. It was first viewed by William Herschel on April 25, 1784 and logged as H VI.8 – but with a less than perfect notation of position. When he reviewed it again on March 10, 1785 he logged it correctly and relabeled it as H VI.19. At a distance of a little more than 40,000 light-years, this 8.5 magnitude globular will show some details to the larger telescope, but remain unresolved to smaller ones. As a halo globular cluster, NGC 5897 certainly shows signs of being disrupted, and has a number of blue stragglers, as well as four newly-discovered variables of the RR Lyrae type.

Now let’s return to Alpha Librae and head about a fistwidth south across the border into Hydra and two degrees east of star 57 for NGC 5694 – also in an attractive field (RA 14 39 36 Dec 26 32 18).

Palomar Observatory, courtesy of CaltechAlso discovered by Herschel, and cataloged as H II.196, this class VII cluster is far too faint for binoculars at magnitude 10, and barely within reach of smaller scopes. As one of the most remote globular clusters in our galaxy, few telescopes can hope to resolve this more than 113,000 light-year distant ball of stars. Its brightest member is only of magnitude 16.5, and it contains no known variables. Traveling at 190 kilometers per second, metal-poor NGC 5694 will not have the same fate as NGC 5897…for this is a globular cluster which is not being pulled apart by our galaxy – but escaping it!

George E. HaleSunday, June 29 – Today we celebrate the birthday of George Ellery Hale, who was born in 1868. Hale was the founding father of the Mt. Wilson Observatory. Although he had no education beyond his baccalaureate in physics, he became the leading astronomer of his day. He invented the spectroheliograph, coined the word astrophysics, and founded the Astrophysical Journal and Yerkes Observatory. At the time, Mt. Wilson dominated the world of astronomy, confirming what galaxies were and verifying the expanding universe cosmology, making Mt. Wilson one of the most productive facilities ever built. When Hale went on to found Palomar Observatory, the 5-meter (200″) telescope was named for him, and was dedicated on June 3, 1948. It continues to be the largest telescope in the continental United States.

Tonight, while we have plenty of dark skies to go around, let’s go south in Libra and have a look at the galaxy pairing NGC 5903 and NGC 5898. You’ll find them about three degrees northeast of Sigma, and just north of a pair of 7th magnitude stars.

Palomar Observatory, courtesy of CaltechWhile northernmost NGC 5903 seems to be nothing more than a faint elliptical with a brighter concentration toward the center and an almost identical elliptical – NGC 5898 – to the southwest, you’re probably asking yourself… Why the big deal over two small ellipticals? First off, NGC 5903 is Herschel III.139 and NGC 5898 is Herschel III.138…two more to add to your studies. And second? The Very Large Array has studied this galaxy pair in the spectral lines of neutral hydrogen. The brighter of the pair, NGC 5898, shows evidence of ionized gas which has been collected from outside its galactic realm – while NGC 5903 seems to be running streamers of material toward its neighbor. A double-galaxy, double-accretion event!

But there’s more…

Look to the southeast and you’ll double your pleasure and double your fun as you discover two double stars instead of just one! Sometimes we overlook field stars for reasons of study – but don’t do it tonight. Even mid-sized telescopes can easily reveal this twin pair of galaxies sharing “their stuff,” as well as a pair of double stars in the same low power field of view. (Psst…slim and dim MCG 043607 and quasar 1514-241 are also here!) Ain’t it grand?

After the black of midnight and out of the blue comes a meteor shower! Keep watch tonight for the June Draconids. The radiant for this shower will be near handle of Big Dipper – Ursa Major. The fall rate varies from 10 to 100 per hour, and lack of lunacy means a great time for the offspring of comet Pons-Winnecke. On a curious note, today in 1908 was when the great Tunguska impact happened in Siberia. A fragment of a comet, perhaps?

Good luck and have a terrific weekend!

This week’s awesome image credits are: Palomar 5 (center of image) – Credit: Palomar Observatory, courtesy of Caltech, NGC 5897 – Credit: Palomar Observatory, courtesy of Caltech, NGC 5694 – Credit: Palomar Observatory, courtesy of Caltech, and the field of NGC 5903 and NGC 5898 – Credit: Palomar Observatory, courtesy of Caltech

Are the Laws of Nature the Same Everywhere in the Universe?

Although we haven’t figured out everything in the universe by a long shot, we’re getting a pretty good a handle on how things work in our world, and how the laws of nature operate here at home. One big question we have is, would laws of nature as we know them function the same at other locations in the universe? A new study says, yes. Research conducted by an international team of astronomers shows that one of the most important numbers in physics theory, the proton-electron mass ratio, is almost exactly the same in a galaxy 6 billion light years away as it is in Earth’s laboratories, approximately 1836.15.

According to Michael Murphy, Swinburne astrophysicist and lead author of the study, it is an important finding, as many scientists debate whether the laws of nature may change at different times and in different places in the Universe. “We have been able to show that the laws of physics are the same in this galaxy half way across the visible Universe as they are here on Earth,” he said.

The astronomers determined this by effectively looking back in time at a distant quasar, labeled B0218+367. The quasar’s light, which took 7.5 billion years to reach us, was partially absorbed by ammonia gas in an intervening galaxy. Not only is ammonia useful in most bathroom cleaning products, it is also an ideal molecule to test our understanding of physics in the distant Universe. Spectroscopic observations of the ammonia molecule were performed with the Effelsberg 100m radio telescope at 2 cm wavelength (red-shifted from the original wavelength of 1.3 cm). The wavelengths at which ammonia absorbs radio energy from the quasar are sensitive to this special nuclear physics number, the proton-electron mass ratio.

“By comparing the ammonia absorption with that of other molecules, we were able to determine the value of the proton-electron mass ratio in this galaxy, and confirm that it is the same as it is on Earth,” says Christian Henkel from the Max Planck Institute for Radio Astronomy in Bonn, Germany, an expert for molecular spectroscopy and co-author of the study.

Their research was published in the journal Science.

Original News Source: Max Planck Institute

Weekend SkyWatcher’s Forecast: June 20-22, 2008

Greetings, fellow SkyWatchers! As the Moon slowly departs from the early evening scene, we have the chance to start the weekend off with shooting stars as we pass through a branch of the Ophiuchid meteor stream. Over the next few days we’ll take a closer look at variable stars, new star clusters and old friends as we head out into the night together…

Friday, June 20, 2008 – Although we will have Moon to contend with in the predawn hours, we welcome the “shooting stars” as we pass through another portion of the Ophiuchid meteor stream. The radiant for this pass will be nearer Sagittarius and the fall rate varies from 8 to 20, but it can sometimes produce unexpectedly more.

Palomar Observatory, courtesy of CaltechFor variable star fans, let’s head towards the constellation of Corona Borealis and focus our attention on S – located just west of Theta – the westernmost star in the constellation’s arc formation. At magnitude 5.3, this long-term variable takes almost a year to go through its changes. It usually far outshines the 7th magnitude star to its northeast – but will drop to a barely visible magnitude 14 at minimum. Compare it to the eclipsing binary U Coronae Borealis about a degree northwest. In slightly over three days this Algol type star will range by a full magnitude as its companions draw together.

NASASaturday, June 21, 2008 – Summer Solstice occurs today at the zero hour. So what exactly is it? Solstice is nothing more than an astronomical term for the moment when one hemisphere of the Earth is tilted the most toward the Sun. Today, the Sun is about 24 degrees above the celestial equator – its highest point of the year. The day of summer solstice also has the longest period of daylight…and the shortest of night; this occurs around six months from now for the Southern Hemisphere.

Palomar Observatory, courtesy of CaltechTonight let’s look forward to the coming summer as we hop a fingerwidth northeast of Beta Ophiuchi (RA 17 46 18 Dec +05 43 00) to a celebration in starlight known as IC 4665. Very well suited to binoculars or even the smallest optics at low power, this magnificent open cluster is even visible to the unaided eye as a hazy patch.

Hanging out in space far from the galactic plane, IC 4665 is anywhere from 30 to 40 million years old – relatively young in astronomical terms! This places the cluster somewhere between the age of the Hyades and the Pleiades. At one time the cluster was believed to have been home to an unusually large number of spectroscopic binaries. While this has been disproved, scopists will enjoy powering up on the approximate 50 members of this association to search for true multiple stars. Enjoy it tonight!

Sunday, June 22, 2008 – Today celebrates the founding of the Royal Greenwich Observatory in 1675. That’s 333 years of astronomy! Also on this date in history, in 1978, James Christy of the US Naval Observatory in Flagstaff Arizona discovered Pluto’s satellite Charon.

NASAWhile observing Pluto is quite possible with a mid-sized (8″) telescope, careful work is needed to separate and identify it from field stars. Just a few days ago, Pluto reached opposition, meaning it is viewable all night. Since it will take several nights of observation for confirmation, right now would be an excellent time to begin your Pluto quest. With a little research you’ll find plenty of on-line locator charts to help guide you on your way!

For observers of all skill levels and equipment, it’s simply time to stop and have a look at a seasonal favorite which is now nearly overhead—M13. You’ll find this massive globular cluster quite easy to locate on the western side of the Hercules “keystone” about a third of the way between the northern and southern stars—Eta and Zeta.

R. Jay GaBanyAt a little brighter than magnitude 6, this 25,100 light-year distant globular cluster can be seen unaided from a dark sky location. First noted by Edmond Halley in 1714, the “Great Hercules Cluster” was cataloged by Messier on June 1, 1764. Filled with hundreds of thousands of stars, yet with only one young blue star, M13 could be as much as 14 billion years old.

Thirty-four years ago, the Great Hercules Cluster was chosen by the Arecibo Observatory as the target for the first radio message delivered into space, yet it will be a message that won’t be received for over 25 centuries. Look at it with wonder tonight… For the light that left as you are viewing it tonight did so at a time when the Earth was coming out of the Ice Age. Our early ancestors were living in caves and learning to use rudimentary tools. How evolved would our civilization be if we ever received an answer to
our call?!

Wishing you clear skies and a wonderful weekend!

The week’s awesome images are Theta Coronae Borealis – Credit: Palomar Observatory, courtesy of Caltech, Solstice and Equinox – Credit: NASA, IC 4665 – Credit: Palomar Observatory, courtesy of Caltech, Pluto and Charon – Credit: NASA, and M13: “The Great Hercules Cluster” is the inspiring work of none other than R. Jay GaBany.

SkyWatcher Alert: Moon, Mars, Saturn and More…

Greetings, fellow SkyWatchers! As the summer heats up for the northern hemisphere and the winter cools down the southern, we’re in for interesting celestial scenery over the next few days. No special equipment is needed – only your eyes and the knowledge of knowing where and when to look….

On the universal date of Sunday, June 8, 2008 the Red Planet – Mars – and the Moon will make a splendid showing for all. As skies darken, look for impressive pair along the western ecliptic. For most of us, Mars and the earthshine Moon will only be separated by about a degree, but for lucky observers in New Zealand, this will be an occultation event! (For specific details on times and areas, please check IOTA information.) Get out your binoculars and have a look. Even the youngest SkyWatcher will easily be able to find Mars!

While the Phoenix mission is still making big news, use this opportunity to do some public astronomy outreach. Point the pair out in the sky to someone and tell what you know. Around 40 years has elapsed since humankind has first visited one – and then the other. How did our original expeditions to the Moon lead scientists to develop ever better instruments for remote study? How has our exploratory spacecraft evolved?

If you think that’s cool… Then stay tuned for Monday, June 9, 2008 when the Moon, Saturn and Regulus team up in the night sky. To the unaided eye, the trio will make a lovely triangle with the Ringed Planet and the Little King situated to the north of Selene. Again, it’s a great time to do some public outreach! Point a telescope Saturn’s way. Titan – Saturn’s largest moon – is visibly bright and can be seen in even small telescopes. Explain how our original fly-bys and landings on our own Moon led us on to explore a moon on a distant world! What did we find on Titan? How can it compare to what we discovered on the Moon and Mars?

Don’t forget Regulus, either. The light you see from it on this night would have left roughly in 1931 – long before expeditions to the Moon, Saturn and Mars were even dreamed of. At about three and a half times more massive than our own Sol, Regulus is one hot customer when it comes to spin rate. Revolving completely on its axis in a little less than 16 hours, oblate Regulus would fly apart if it were moving any faster! Even though it’s been around for a few million years, Regulus isn’t alone, either. The “Little King” is a multiple star system composed of a hot, bright, bluish-white star with a pair of small, faint companions.

Even if you only use your eyes, the next few days are a great opportunity to share what you love and know with others… Enjoy!

Moon Occulting Mars Image – Credit: Ron Dantowitz, Clay Center Observatory at Dexter and Southfield Schools. Saturn and Titan – Credit: Casinni/NASA. Regulus vs. the Sun – Wenjin Huang

What is the Fastest Spinning Object in the Solar System? Near-Earth Asteroid 2008 HJ

The asteroid Eros, it might be big but it doesnt spin as fast as 2008 HJ (NASA)

A British astronomer has discovered a strange spinning object. The fact that it is spinning in itself is not strange, but the speed it is doing so has raised some eyebrows. The near-Earth asteroid 2008 HJ has been spotted spinning at a rate of one rotation every 42.7 seconds, breaking the record for the fastest rotating natural object in the Solar System. It is so fast that it has been designated as a “super-fast rotator”. What makes this discovery even more interesting was that it was spotted by an amateur astronomer when using the Australian Faulkes Telescope South observatory, operating it remotely over the Internet, in his Dorset home in the south of the UK…

Asteroid 2008 HJ smashes the previous record for fastest rotating object by 35 seconds. The previous record holder was asteroid 2000 DO8 (discovered eight years ago) with a rotational period of 78 seconds. This new discovery comes from a new project funded by the Science and Technology Facilities Council (STFC), which gives UK schools and colleges access to the world-class Faulkes Telescopes based in Australia and Hawaii. This finding is one of four recent successes in the search for small near-Earth asteroids under 150 meters in diameter. In April this year, the first significant discovery by the project was of asteroid 2008 GP3 with a measured rotation period of 11.8 minutes.

The orbit of NEO 2008 HJ (NASA/JPL Small Body Database)

Perhaps even more exciting than the discovery itself is who spotted asteroid 2008 HJ in the first place. This isn’t a news release from the Australian observatory, it isn’t even an announcement from an academic institution; the discovery was made by retiree Richard Miles from the comfort of his own home. Miles is an amateur astronomer and vice-president of the British Astronomical Association (BAA). He was able to carry out his research via a remote connection to the Faulkes Telescope South on the other side of the planet, in the UK. This charity based program enables enthusiasts and students to control the research-grade two-metre diameter telescopes, and the discoveries are coming thick and fast.

A discovery like this demonstrates the capabilities of amateur astronomers and school students to produce exciting scientific results if given the right tools. By providing Richard with access to a big telescope we have smashed the previous record, and opened up the search for even faster objects to UK amateur astronomers and school students. This helps to put all that classroom science, maths and IT to real use!” – Dr Paul Roche, Director of the Faulkes Telescope Project at Cardiff University, Wales

The finding of the 12×24 metre asteroid appears to be consistent with near-Earth asteroid theory, and many sub-minute period asteroids can be expected. It’s just that not very many have been discovered as yet, so with the help of UK schools and amateur astronomers, more can be expected to be found.

Near-Earth asteroids are a concern for the future of the planet as there are many Earth-crossing rocky bodies that could cause significant damage to us on the ground should one come our way. Although the skies appear clear for now, our knowledge of these rogue objects is very limited. It is generally understood that these spinning pieces of rock (often weighing in at thousands of tonnes) are fragments from ancient collisions in the early Solar System. Projects such as Faulkes have an obvious advantage in increasing our knowledge in that it opens up observation time to a vast number of astronomers.

For more information on the Faulkes Telescopes, go to the project website »

Source: SpaceRef.com

2012: No Planet X

Will Planet X cause mayhem in 2012? Nope.

Apparently, Planet X (a.k.a. Nibiru) was spotted by astronomers in the early 1980’s in the outermost reaches of the Solar System. It has been tracked by infrared observatories; seen lurking around in the Kuiper Belt and now it is speeding right toward us and will enter the inner Solar System in 2012. So what does this mean to us? Well, the effects of the approach of Planet X on our planet will be biblical, and what’s more the effects are being felt right now. Millions, even billions of people will die, global warming will increase; earthquakes, drought, famine, wars, social collapse, even killer solar flares will be caused by Nibiru blasting through the core of the Solar System. All of this will happen in 2012, and we must begin preparing for our demise right now…

As investigated in my previous article “No Doomsday in 2012“, a lot of weight had been placed on the end of an ancient Mayan calendar, the “Long Count”. According to this calendar and Mayan myth, something is going to happen on December 21st, 2012. Now the world’s Planet X supporters seem to have calculated that this hypothetical, deadly planet will arrive from a highly eccentric orbit to wreak gravitational havoc on Earth, sparking geological, social, economic and environmental damage, killing a high proportion of life… in 2012.

Related 2012 articles:

I’m sorry, but the “facts” behind the Planet X/Nibiru myth simply do not add up. Don’t worry, Planet X will not be knocking on our door in 2012 and here’s why…

Nibiru and Planet X
The planet Neptune - could its orbital deviations reveal Planet X (NASA)

In 1843, John Couch Adams (a British mathematician and astronomer) studied the orbital perturbations of Uranus and deduced that through gravitational interactions, there must be an eighth planet, tugging at the gas giant. This led to the discovery of Neptune, orbiting at a distance of 30AU from the Sun. There have been numerous occasions where this method has been used to deduce the existence of other bodies in the Solar System before they were directly observed.

Neptune was also experiencing orbital perturbations, and on the discovery of Pluto in 1930, it was thought that the aptly named “Planet X” had been discovered. Alas, Pluto’s mass was tiny, and once the orbit of Charon (Pluto’s moon) was analysed it was found that the mass of the Pluto-Charon system was far too small to affect the orbit of Neptune. The hunt for Planet X continued…

After years of speculation and historic research, it was believed that a huge body astronomers were looking for was a huge planet or a small star, possibly a companion to our Sun (making the Solar System a binary system). The name “Nibiru” was unearthed by the author Zecharia Sitchin, on researching the possible intervention of extraterrestrials in the early history of mankind. Nibiru is a hypothetical planet as taught in ancient Sumerian culture (the Sumerians existed from around 6,000BC to 3,000BC, predating Babylon, in the current geographic location of Iraq). There is very little archaeological evidence to suggest this mythical planet has anything to do with Planet X. But since this dubious connection, Planet X and Nibiru are now thought by doomsayers to be the same thing, an ancient astronomical body that has returned after a long orbit beyond the Solar System.

OK, so the Nibiru/Planet X connection might be a bit ropey already, but is there any solid evidence for the modern-day Planet X?

Infrared observations = Planet X
A popular image on Planet X websites. Is this Planet X, or is it simply a young galaxy? (NASA - possible source)
There is much emphasis placed on the 1983 “discovery” of a mysterious heavenly body by NASA’s Infrared Astronomical Satellite (IRAS) on the outskirts of the Solar system, some 50 billion miles (540 AU) away. Naturally the world’s media will have been very excited by such a discovery and began making noises that perhaps this was Planet X (the most popular accessible resources for Planet X advocates is the Washington Post article published on December 31st 1983 titled “Mystery Heavenly Body Discovered“). In actuality, astronomers weren’t sure what the infrared object was (the clue is in the word “mystery”). Initial media reports postulated that it could be a long-period comet, or a planet, or a far-off young galaxy or a protostar (i.e. a brown dwarf). As soon as the last possibility is mentioned, suddenly this became the “discovery” that Planet X was in fact a brown dwarf orbiting in the outer reaches of our Solar System.

So mysterious is the object that astronomers do not know if it is a planet, a giant comet, a nearby “protostar” that never got hot enough to become a star, a distant galaxy so young that it is still in the process of forming its first stars or a galaxy so shrouded in dust that none of the light cast by its stars ever gets through.” – Thomas O’Toole, Washington Post Staff Writer, December 30th 1983 (from text on the Planet X and Pole Shift website)

So where did the Washington Post get its story? The story was published in response to the research printed a paper titled “Unidentified point sources in the IRAS minisurvey” (by Houck et al, published in Astrophysical Journal Letters, 278:L63, 1984). Dr. Gerry Neugebauer, co-investigator in the IRAS project, was interviewed and strongly stated that what IRAS had seen was not “incoming mail” (i.e. the results did not suggest there was an object approaching Earth). On reading this interesting research, I was especially drawn to the paper’s conclusion:

A number of candidate identifications have been considered including near-solar system, galactic, and extragalactic objects. Further observations at infrared and other wavelengths may provide additional information in support of one of these conjectures, or perhaps these objects will require entirely different interpretations.” – Houck et al, Astrophysical Journal Letters, 278:L63, 1984.

Although these IRAS observations were seeing mysterious objects, at this stage, there was no indication that there was an object (let alone a brown dwarf) powering its way toward us. But the rumours had already begun to flow. When follow-up papers were published in 1985 (Unidentified IRAS sources – Ultrahigh-luminosity galaxies, Houck et al., 1985) and 1987 (The IRAS View of the Extragalactic Sky, Soifer et al., 1987), there was little if any media interest in their findings. According to these publications, most of the IRAS observations in the 1984 paper were distant, ultra-luminous young galaxies and one was a filamentary structure known as “infrared cirrus” floating in intergalactic space. IRAS never observed any astronomical body in the outer reaches of the Solar System.

Orbital perturbations = Planet X
The bodies in the Kuiper Belt (Don Dixon)
In addition to the 1983 “discovery” of the Planet X brown dwarf, the 1992 Planet X claim goes something like this: “Unexplained deviations in the orbits of Uranus and Neptune point to a large outer solar system body of 4 to 8 Earth masses, on a highly tilted orbit, beyond 7 billion miles from the sun,” – text from an un-cited NASA source on the “Planet X Forecast and 2012 Survival Guide” video.

Pulling up the discovery of planets using orbital perturbation measurements, Planet X advocates point to a NASA announcement that in 1992, there were indirect measurements of a planet some 7 billion miles from Earth. Alas, I cannot find the original source for this claim. The only huge discovery NASA announced along these lines was the discovery of the first major trans-Neptunian object (TNO) called 1992 QB1 (full details of the discovery of this “cubewano-class” object can be found in the original announcement transcript). It has a diameter of 200km and is confined to the Kuiper Belt, a zone of minor planets (where Pluto lives) and asteroids from 30AU to 55AU, just outside Neptune’s orbit. Some of these bodies (like Pluto) cross the path of Neptune’s orbit and there therefore designated as a TNO. These TNO’s pose no threat to the Earth (in as much as they wont be leaving the Kuiper Belt to pay us a visit in 2012).

Since then, any Neptune orbital perturbations have been put down to observational error and have since not been observed… so there doesn’t appear to be any obvious object any bigger than the largest Kuiper Belt objects out there. Still, to keep an open mind, there could be more large bodies to be discovered (that might explain why there is such a steep drop-off of Kuiper Belt objects at the “Kuiper Cliff”, the jury is out on that idea), but there is no evidence for a massive body approaching from the vicinity of the Kuiper Belt. Even the strange Pioneer anomaly that the Pioneer and Voyager probes are experiencing cannot be attributed to Planet X. This anomaly appears to be a Sun-ward acceleration, if there was a massive planet out there, there should be some gravitational effect beyond what has been predicted by the other known objects in the Solar System.

4-8 Earth masses = a brown dwarf? It must be Planet X.
Brown dwarfs are 15-80 times the mass of Jupiter (NASA)
Probably the most glaring inconsistency in the Planet X hypothesis is the Planet X advocates assertion that the 1984 IRAS object and the 1992 body are one of the same thing. As announced on many websites and online videos about Planet X, the 1984 IRAS observation saw Planet X at 50 billion miles from Earth. The 1992 NASA “announcement” put Planet X at a distance of about 7 billion miles from Earth. Therefore, the logic goes, Planet X had travelled 43 billion miles in the course of only eight years (from 1984 to 1992). After some dubious mathematics, Planet X is therefore expected to reach the core of the Solar System in 2012. (Although many believed it should arrive in 2003… they were obviously wrong about that prediction.)

Well, I think we might be clutching at straws here. For starters, for the 1984 object to be the same as the 1992 object, surely they should be the same mass? If Planet X was a brown dwarf (as we are led to believe in the IRAS observations), how can it possibly weigh in at only 4 to 8 Earth masses eight years later? Brown dwarfs have a mass of around 15-80 Jupiter masses. As Jupiter is about 318 Earth masses, surely the object hurtling toward us should have a mass of somewhere between 4,770 and 25,440 Earth masses? So I am going to go out on a limb here and say that I reckon the 1984 object and the 1992 object (if either object actually existed that is) are not the same thing. Not by a very long shot.

If there is no evidence supporting Planet X, it must be a conspiracy
If it can be this easy to cast the fundamental “scientific” theory behind Planet X into doubt, I see little point in discussing the historical reasons (mass extinctions, volcanic activity, earthquakes etc.) as to why the doomsayers believe Planet X should exist. If there is no renegade planet out there of significant mass, how can Nibiru be a threat to us in 2012?

They will have us believe there is a global conspiracy of international governments hiding the facts from us. NASA is involved in the cover-up, hence the lack of evidence. In my opinion, simply because there is no evidence, doesn’t mean there is a conspiracy to hide the truth from the public. So why would governments want to hide a “discovery” as historic as a doomsday planet approaching the inner Solar System anyway? To avoid mass panic and pursue their own, greedy agendas (obviously).

As it turns out, this is the only strength behind the Planet X myth. When confronted with scientific facts, the Planet X advocates reply with “…governments are sending out disinformation and covering up the true observations of Nibiru.” Although I enjoy a good conspiracy theory, I will not support anything in the name of Planet X. If the basic science behind what we are led to believe are the foundation of Planet X existing is wrong, it seems a poor argument to say “the government did it”.

Therefore, the story that Planet X will arrive in 2012-21-December is, in my view, total bunkum (but it helps to sell doomsday books and DVDs by scaring people). Nibiru will remain in the realms of Sumerian myth.

Sources: No Tenth Planet Yet From IRAS, Surviving 2012 and Planet X (Video), The SAO/NASA Astrophysics Data System, New Scientist, IRAS, Planet X and Pole Shift

Here’s information on the 2012 comet, 2012 doomsday

Leading image credits: MIT (supernova simulation), NASA/JPL (extrasolar planet). Effects and editing: myself.

Navigation for Spaceships Using X-ray Pulsars: Introducing XNAV

Pulsar diagram (© Mark Garlick)

This could be the ultimate galactic GPS system: using pulsars as an interstellar navigation tool. Rapidly spinning neutron stars emit focused beams of X-rays into space and many, with accuracy as good as an atomic clock, have been mapped by astronomers. Now these pulsars may have a very important practical use. These interstellar beacons may be used to get a fix on the position of spacecraft and guide them around space…

Ever since the first X-ray pulsar was discovered in 1967 (called Centaurus X-3, the third X-ray source discovering in the constellation of Centaurus with a period of 4.84 seconds), astronomers have been busy mapping the distribution of these rapidly spinning stellar objects. Pulsars are the embodiment of a neutron star binary system; the neutron star strips the material from its stellar neighbour, accelerating the gas to about half the speed of light, blasting hot collimated X-ray emissions from its poles. As the pulsar spins, these beams of light act like a lighthouse, and should they be directed toward the Earth, we observe a highly accurate periodic flashing of X-rays.

At the beginning of this month, the IEEE/ION Position, Location and Navigation Symposium (PLANS) 2008 conference in Monterey, California featured two interesting concepts for the use of these highly accurate X-ray sources. The first proposal called “Noise Analysis for X-ray Navigation Systems” headed by John Hanson of CrossTrac Engineering, introduces a scaled-up version of terrestrial GPS, using pulsars rather than man-made satellites. The system is called X-ray navigation, or “XNAV” for short. Primarily focusing on space missions beyond Jupiter, XNAV would use the Solar System as the base co-ordinate and then measure the phase of the incoming X-ray emission from the mapped pulsars. As the X-ray pulses are so accurate, onboard systems could measure and compare the signal from multiple pulsar sources and automatically deduce the position of the spacecraft to a high degree of certainty. I suppose it would be an advanced 3D version of the traditional sextant as used by ships to measure the elevation of stars above the Earth’s horizon.

The second concept entitled “Online Time Delay Estimation of Pulsar Signals for Relative Navigation using Adaptive Filters“, is headed by Amir Emadzadeh at the UCLA Electrical Engineering Department. Emadzadeh suggests that the location of two spacecraft can be worked out if both ships are looking at the same, known pulsar. The periodic emission measured by both ships will have a differential time delay proportional to the distance between the ships. In addition, the UCLA group suggest a method to derive their relative inertial position by observing a distribution of X-ray sources throughout the cosmos.

These are very interesting concepts, but until we begin routinely venturing beyond the orbit of Jupiter I doubt we’ll see these ideas come to fruition any time soon…

Original source: Space.com
Additional info: IEEE/ION PLANS 2008 conference

Over 100 Explosions Observed on the Moon

In the past two and a half years, the Moon has taken a real beating. NASA astronomers have observed over a hundred explosions on the Moon during this time, caused by meteoroids both large and small, slamming into the Moon at speeds of up to 160,000 miles per hour (257,495 kilometers per hour).

The Moon gets pelted constantly – over a metric ton of material falls on the Moon every day! Most impacts are too dim to see with the naked eye because they are small micrometeorites. The rate of the flashes from larger impacts increases dramatically – up to an impact every hour – during meteor showers such as the Perseids and Quadrantids. The sporadic impacts account for twice as many observable events as compared to meteor shower impacts.

If you were standing on the Moon, you wouldn’t see these impacts as “shooting stars,” though, since there is no atmosphere in which they can burn up. The explosion is also not something like one would see here on Earth, as the absence of oxygen doesn’t allow for any combustion. The kinetic energy of the impact heats up the rocks on the surface to the point where they become molten, and glow for a short period after the impact.

Pictured left is the flash from a confirmed impact on March 13th, 2008, as captured by amateur astronomer George Varros. The small white point in the bottom right of the picture is where the impact occurred. He has an animation of the event on his site.

Monitoring the number of impacts on the Moon is important for future missions to visit our smaller neighbor, as well as for the eventual establishment of a Moon base. It will be important to know when astronauts should take cover from potential strikes during peak periods of impacts. After all, even a small meteoroid traveling between 4500 mph (7,242 kph) and 160,000 mph (257, 495) could do a lot of damage to a space suit or lunar base. A typical blast that can be seen with a backyard telescope from Earth is equivalent to a few hundred pounds of TNT. I know I wouldn’t want to go for a Moon walk during a meteor shower…

NASA has been observing lunar impacts with one 14-inch (36 cm) telescope and one 20-inch (51 cm) located at the Marshall Space Flight Center in Alabama, and one 14-inch telescope located in Georgia.

But it’s not just NASA that can see these lunar fireworks: NASA’s Meteoroid Environment Office has called for amateur astronomers to help in recording and confirming these flashes. If you have a lot of patience, a telescope and a way to record the flashes, check out their site to get started.

Source: Physorg, NASA