Wednesday, January 31, 2007

Around the Moon


NASA is studying a plan to have astronauts travel around the Moon around 2015, similiar to the Apollo 8 mission. This would use a rocket design combining the Ares V main stage with the upper stage of Ares I. This combination has been called Ares IV. This mission would allow test of a "skip entry" technique for landing on Earth.

Meanwhile Europeans and Russians are considering a similiar mission at about the same time. It would be embarassing for the US if somebody else got there first. If you have 100 million to spend on a holiday, Russia's Energia will fly YOU around the Moon in a Soyuz spacecraft. Everybody start saving those pennies!

NASA has planned a manifest of Orion missions. Some of these flights will service the ISS. NASA has no ISS flights planned for Orion after 2016. Hopefully a privately developed rocket will take over from there. Presently Orion 13 is planned for December 2019. During this 21-day mission 3 astronauts will finally set foot upon the Moon.

Tuesday, January 30, 2007

PAN-STARRS


The Panoramic Survey Telescope and Rapid Response System (PAN-STARRS) is designed to observe the entire sky several times per month. Its primary goal is to discover dangerous objects that might pose a threat to Earth. A wide-field survey will also help locate new Kuiper Belt Objects, extrasolar planets, gamma ray bursts and many other interesting objects. This ground-based system is less expensive and potentially more useful than Space-based surveys.

For cosmology, the system will allow surveys of galaxy clustering and gravitational lensing. For those interested in Type Ia supernovae, PAN-STARRS can locate 5000 of them. A far more expensive Joint Dark Energy Mission would only detect about 2000. JDEM concepts like SNAP would have a lifetime measured in months, and could not be repaired like Hubble. PAN-STARRS will last indefinitely. More supernovae for 1/10 the cost, a very good deal.

This prototype telescope was dedicated June 30 atop Haleakala on Maui. This is Hawaii's "other" telescope mountain; 10,023 feet high. The US Air Force has maintained observatories here for many years. The full system will have 4 telescopes, erected either here or on Mauna Kea. The latter has better observing conditions and infrastructure, but faces local concerns about overbuilding on a sacred mountain.

As this is written, the Hubble Advanced Camera for Surveys (ACS) is broken, probably beyond repair. The ACS was installed during Servicing Mission 3B in March 2002. It has been used for surveys of everything from supernovae to galaxies. Some spectacular photos of gravitational lensing came from ACS. The camera is not scheduled to be replaced on the servicing flight. That mission is currently scheduled for September 11, 2008; the last flight of Shuttle Atlantis.

Kicking Asteroids


Dr. Edward Lu was a physicist at Hawaii's Institute for Astronomy before being chosen as an astronaut. In 2003 he spent 6 months aboard ISS. Back on Earth, he has been studying the problem of dangerous asteroids. He is part of the B612 Foundation, named for the Little Prince's home. With fellow astronaut Stan Love, he has proposed a "gravity tractor" to deflect an asteroid's orbit.

Last week Edward Lu, astronomer Nick Kaiser and others gave a presentation for us at the University of Hawaii. The system would use the spacecraft's small gravitational field as a tractor beam to gently tug an asteroid. If a tiny change is made early enough, the cumulative shift would turn an Earth encounter into a miss. The nudge might have to be made decades in advance, so it is good to start planning now.

To quote that other movie from 1998, ARMAGEDDON:

"In the Book of Revelations, the Bible speaks of a final day on Earth, when all mankind shall perish, shall cease to exist. This day is known as Armageddon...for the first time in the history of this planet, a species possesses the technology to prevent its own extinction."

Of all life on Earth, the human species is uniquely adapted for spaceflight. Hands with opposable thumbs for building things, capacity to cooperate toward a common goal, the desire to expand one's horizons are all useful traits. Recently I have found that our skin can be adapted for Space. Exploration of Space is an imperative for survival.

Monday, January 29, 2007

Apophis


Interest continues to grow. Thank you, Samwise, for including this little blog on your roll. As you would say, "There's some good left in this world, and it's worth fighting for!" Thanks also to Mixed States and Megite Science News for adding to your feed.

Thanks to Astroprof too. This week his interest in asteroids coincides with mine. Asteroid 99942 Apophis was only discovered in 2004. On April 13, 2029 Apophis will pass extremely close to Earth, lower than our communications satellites. In 2036 it will come by again. There is a danger, but this is also an opportunity for a spacecraft rendezvous.

We can only compute probabilities whether an asteroid will strike the Earth. Recently I have been assigned to track asteroids, and it is a tricky business. Usually they are just streaks on a photographic exposure, subject to all the vagaries of atmospheric distortion. I've computed Apophis' position on November 2, 2012 when it will pass between Earth and the Sun. Projecting this orbit further into the future eats up more computer time and introduces more uncertainties

One solution is to follow an asteroid the way they we track aircraft, with a transponder. Currently NASA lacks the budget to land something on Apophis, but the Planetary Society is soliciting proposals. The Orion CEV should be in full operation before 2029; someone should consider a crewed mission. We may not land on Mars by then, but Apophis is a target which may someday touch our lives.

Sunday, January 28, 2007

Onizuka


The Onizuka Space Center on the grounds of Keahole-Kona airport. Colonel Ellison Onizuka was born and graduated from high school in Kealakekua-Kona. His grandparents came from Fukuoka, Japan; and his wife was also from the Big Island. Captain James Cook died near Kealakekua, on a mission to circle Earth that Cook never completed.

Onizuka became Hawaii's first astronaut on mission STS-51C in 1985. As part of the Challenger crew, he died on January 28, 1986. His name also survives in the Onizuka Centre for International Astronomy on the slopes of Mauna Kea, and Onizuka Air Force Base in California.

Oh! I have slipped the surly bonds of earth,
And danced the skies on laughter-silvered wings;
Sunward I've climbed, and joined the tumbling mirth
Of sun-split clouds, --and done a hundred things
You have not dreamed of --Wheeled and soared and swung
High in the sunlit silence. Hov'ring there
I've chased the shouting wind along, and flung
My eager craft through footless halls of air...
Up, up the long, delirious, burning blue
I've topped the wind-swept heights with easy grace
Where never lark or even eagle flew --
And, while with silent lifting mind I've trod
The high untrespassed sanctity of space,
Put out my hand, and touched the face of God

Saturday, January 27, 2007

Saturn's Polar Storm

Video of Saturn's immense polar storm, 8000 kilometres in diameter. The ring clouds surrounding the eye are 20 to 45 kilometres high. Winds blow at 550 kilometres per hour. Cyclones on Earth are formed by warm gas underlying a cold layer. The source of heat is below the surface and concentrated at the South Pole. The jet of a singularity would produce an effect very much like this. The Black Hole's rotation axis coincides with that of Saturn, which is also why Saturn's magnetic poles are lined up with the planet's rotation axis.

Friday, January 26, 2007

Saturn Aurora

From the Hubble Space Telescope, 10 seconds of Saturn's aurora in ultraviolet. As with Earth, there is a corresponding aurora at the North Pole. The "hot spot" is only at the South Pole, indicating that the aurora is not the cause of heating. Something else is keeping the planet warm.

Saturn Mystery


This week's issue of NATURE reports that old theories of Saturn's heat are seriously lacking. It has long been known that Saturn radiates 2.8 times as much heat as it receives from the Sun. This was supposed to be caused by the auroras observed at Saturn's poles. Some completely unknown process would then tranfer this heat to the equator. New calculations reveal that this process would in fact make the equator cooler!

"This unexplained energy crisis represents a major gap in our understanding of these planets' atmospheres," the authors wrote, "we need to re-examine our basic assumptions about planetary atmospheres and what causes the observed heating."

As first reported here last Summer, our Subaru telescope atop Mauna Kea has located a hot spot centred within 2-3 degrees of the South Pole, most visible at 17.65 microns. The hot spot, with the hottest temperatures of the surface, is well within the auroral ring. The aurora DOES NOT cause the hot spot. A closer look by the Cassini spacecraft has revealed an immense tornado-like storm at the pole. Tornadoes on Earth result from a warmer layer of atmosphere beneath a cooler upper layer. Something within Saturn is heating the lower layers of her South Pole.

Today's Cassini photo was taken by the Visual Intrared Imaging Spectrometer. Saturn's night side glows nearly as bright as day. A singularity at Saturn's centre would explain both internal heat and the planet's magnetic field. Because Saturn’s magnetic poles coincide with her geographic poles, the hot spot of a singularity would be centred at the South Pole exactly as observed.

Thursday, January 25, 2007

Moon Breaking Apart--Not


A couple of interesting items from this week's news:

SPACE.com reported Monday on unpublished research indicating that the Moon will someday break up. This is based on the old idea that the Sun's temperature is slowly rising. According to the "Faint Young Sun" idea, when Earth was formed the Sun was barely 70% as luminous and Earth's temperature was below freezing. This supposition is contradicted by the geological record. Standard models predict that the Sun's luminosity will continue to rise until Earth's oceans boil and the Moon breaks up.

As we know, c has been changing according to GM=tc^3. The Sun turns fuel to energy according to E=mc^2. On the graph, the standard model has solar luminosity L/Lo as an increasing curve. When c change is factored in, the curve becomes a nearly level line. This is very powerful evidence in favour of c change. If the speed of light had not changed in precisely the amounts predicted, life would not have evolved to read this post. Earth and the Moon will be around for quite a while.

It is possible to believe that some unknown process has custom-heated Earth's temperature for our comfort. It is also possible to believe that we live between periods of inflation and cosmic acceleration, just as Earth is the centre of the Universe. All these explanations rely on inferred energies that can't be observed. They also share the quality of being fine-tuned for our present time, Even dark energy advocates call this the Nancy Kerrigan paradox: "Why me, why now?"

The new issue of Scientific American has "dark energy" on the cover, assuring that the idea will be promoted for a while longer. The same publication did not mention Special Relativity at all until 1911, 6 years after Einstein's papers were published. Before that, they featured many articles about ether. Fortunately, Earth has many billions of years to get it right.

Wednesday, January 24, 2007

Minor Planets


The lines between asteroids, comets and minor planets become even more blurred. Astronomer Mike Brown discovered the Kuiper Belt Object Eris, formerly called Buffy. Discovery of these objects has changed definitions such that Pluto has been demoted to a "minor planet." At AAS earlier this month, Brown announced calculations that Object 2003 EL61 may someday become a comet.

The object is the size of Pluto, but is shaped like an American football spinning end over end. You can see animations of this spin at Mike Brown's 2003 EL61 page. This asteroid has two known satellites and orbits outside Neptune's orbit. Interactions with Neptune may someday alter 2003 EL61's orbit, turning a minor planet into a comet.

Above is a Hubble Space Telescope photo of Vesta. We are fortunate to have samples from this asteroid. In October 1960 two fence workers in Millbillie, Australia saw a fireball in the sky. Western Australia is a big place, and it was ten years before the meteorites were found. Comparing their makeup with spectrographic data showed that the meteorites came from Vesta.

The meteorites are mostly composed of pyroxene, a mineral common in our Hawaiian lava. Vesta's surface is mostly basaltic rock, the product of lava flows. Evidence indicates that Vesta once had a molten core, like Earth. Old ideas of radioactive decay would have difficulty accounting for this heat. Samples from Vesta and other meteorites show no sign of radioactive materiels.

On the right is a computer reconstruction. The bottom of the asteroid is one enormous impact crater, including a high central peak. An impact this big could have torn Vesta to pieces. An internal singularity would have kept things together, and explained Vesta's internal heat. Vesta will be the first asteroid destination of the DAWN probe.

Vesta is pictured below with Ceres, the second asteroid to be explored by DAWN. As much as 25% of Ceres may be water, possibly more water than Earth. Ceres' spherical shape indicates that it too has internal heat. The inner core has been interpreted as rock, but could contain something else. As minor planets, these worlds will be excellent places to search for singularities.

Tuesday, January 23, 2007

Journey to an Asteroid Continued


The least expensive missions receive the least publicity. On June 20 the DAWN spacecraft is scheduled for launch. This low-cost mission that was nearly cancelled before being reinstated less than a year ago. DAWN will use an ion propulsion system as used on the Deep Space One mission. The spacecraft will flyby Mars in March '009, arrive at asteroid Vesta in October 2011 and depart in April 2012. For the climax, DAWN will rendezvous with Ceres from February to July 2015. Remember, visiting an asteroid takes less energy than landing on the Moon.

This mission will begin a new age of asteroid exploration. Vesta and Ceres may tell us about the formation of the solar system. Here it is predicted that they are not just big rocks. The asteroids could harbour water, internal heat, and possibly conditions for life.

These are truly new worlds about which little is known. When you consider the many asteroids, moon and Kuiper Belt Objects, our solar system contains HUNDREDS of unexplored worlds. Like the Little Prince's Planet, even tiny worlds can contain surprises. Exploration of asteroids and comets may literally save the Earth.
Deep Impact-Cam

The last footage from the Deep Impact probe July 4, 2005. Comets are theorised to be mostly made of water ice. Impacts in the past may have given Earth its water. If large asteroids like Ceres turn out to contain water, they may also have contributed.

Monday, January 22, 2007

Journey to an Asteroid


The Orion CEV will create capabilites that have not existed since the time of Apollo. We have a Vision to reach the Moon, which humans first visited in 1969, and Mars someday after that. A huge number of strange new worlds are surprisingly close. NASA has been studying a mission to go where no one has gone before, to an asteroid.

In many ways an asteroid mission is even easier than reaching the Moon. Many asteroids pass nearly as close. Unlike the Moon or Mars, an asteroid does not have a big gravity well to descend into. Without even using a landing vehicle, an Orion could approach very close to an asteroid. The practical payoff could be enormous, because one of these Earth-crossers will someday hit the Earth!

Surprisingly little is known about the makeup of asteroids. The only "sample return" so far is from meteorites. Researchers are not sure whether they are solid objects or big rubble piles. That complicates any attempt to land on an asteroid or deflect it from Earth. Many asteroids are peanut-shaped, indicating that they are formed from two objects bumping into one another. Some asteroids may in fact be two objects orbiting closely around their common center of gravity.

The image of asteroids as big rocks may not be completely correct. The largest asteroid is Ceres, 580 kilometres in diameter. Observations recently published in NATURE suggest that Ceres may be largely made of water! It may contain even more water than the Earth. Water-asteroids striking the Earth may explain how we acquired water in the first place.

The best views of Ceres are from the Hubble Space Telescope. Though the view is fuzzy, Ceres has a mysterious bright spot. This looks a lot like the hot spot of Enceladus, a moon which contains water and is about the same size. Models of Ceres point to a differentiated interior, indicating an internal source of heat. Ceres may be considered a minor planet, with the same processes we have seen on other bodies. As with Enceladus, the interior of Ceres may be modelled with an internal singularity.

Friday, January 19, 2007

Gentler Deep Impact

July 4 a big screen was set up on Waikiki Beach to watch the Deep Impact probe encounter Comet Temple 1. Nearly 10,000 people showed up to watch. There is a lot of interest in astronomy out there!
Deep Impact

From the 1998 movie DEEP IMPACT. A comet hitting the Atlantic producers effects similiar to a collapse of Cumbre Vieja. Good special effects, but remember that Kealakekua Bay's creation caused a wave that submerged the island of Kaho'olawe, 1427 feet high. Coincidentally, the Empire State Building is about the same height, 1472 feet. Like the comet, the energy of earthquakes originated in Space.

Thursday, January 18, 2007

Cumbre Vieja


Cumbre Vieja volcano in the Canary Islands looks peaceful now. Undersea surveys have found a 400 cubic km landslide, the debris of a prehistoric eruption. Previous activity has caused the Western slope to come loose, creating a North-South fracture. Another large eruption would cause 500 cubic kilometres of mountain to crash into the sea. Dr. Simon Day and Steven Ward have modelled what would happen next.

The initial impact would create a water dome 900 meters high, collapsing and spreading like a stone creating ripples. A massive tsunami would race across the Atlantic at nearly 800 km/hr. The coast of Morocco would be struck by waves 100 meters high. Waves up to 50 meters from crest to trough would strike the US East Coast. Water would inundate coasts from Britain to Brazil.

The Indian Ocean tsunami of 2004 produced waves up to 30 m high. Krakatoa's eruption in 1883 created 6 m waves, killing 30,000 people. The damage in New York City alone would make 9/11 look like a college prank. The Northeastern US is also vulnerable to earthquakes. As recently as 1925 a magnitude 7 quake struck the region. Unlike California or Hawaii, New York has never prepared for a major earthquake.

Before Einstein and Planck some scientists believed they knew everything about physics. Even today some will tell you that they have inventoried everything in the Universe. It is the height of folly to think we know everything in nature. Previously humans did not suspect what lies beneath their feet. The hiccoughs of a Black Hole less than a millimetre across can wipe out whole coastlines. The Universe has power and mysteries far beyond human understanding.

Wednesday, January 17, 2007

Kealakekua


A favourite place, Kelakekua Bay on the Big Island. It was the site of great tragedy when Captain Cook's blood was spilled in 1779. Today it has some of the best snorkelling reefs on the island. The nearest shore access is a mile from Cook's monument. From there you can swim or take a boat to the reef. Spinner dolphins are often seen in the bay too.

See that steep cliff on the far side of the bay? As we saw last year, lava flows like this one (below) form benches at the shore that can collapse and break off. The Big Island is less than one million years old, a baby in geological terms. Kealakekua Bay was created just 120,000 years ago when a 30-km chunk of the shore broke off and slid into the sea. The resulting tsunami completely submerged the island of Kaho'olawe, 1427 feet high! The wave continued and nearly inundated the island of Lanai. Today on Lanai you can still find chunks of coral at the 1000-foot level.

Diving around the island opens our eyes to a new world. The undersea shoreline around the Big Island is dotted by slide zones. Many times submerged landslides have caused tsunamis to march across the Pacific. In 1964 a tsunami begun in an Alaska quake killed 11 people in Crescent City, California. Soon we will see that even New York City lies in the path of a tsunami.

Laupahoehoe


Laupahoehoe Point, on the Big Island's Northwest shore. This is the rainy side of the island. At one time there was a school there, built right by the ocean. On April 1, 1946 a tsunami swept away the school, much of the coast, and about 159 lives. Hawaiians know first-hand the power of Madame Pele.

The fury of earthquakes and volcanoes is leftover energy from the Big Bang. In the first moments of Creation, many billions of Black Holes were created. One tiny singularity survives at Earth's centre. It triggered the planet's formation as a pearl forms around a grain of sand. Radiation from this object eventually makes its way to the surface as heat, which makes Earth a dynamic planet. Life on Earth, or even the planet itself, would not exist save for this tiny object.

We will see in upcoming posts that Hawaii is not the only place threatened by Madame Pele. The islands are just the centre of a Pacific Ring of Fire. On December 26, 2004 South Asia learned the hard way about the power of tsunamis. Even New York City is vulnerable to earthquakes and tsunamis.

Laupahoehoe is also the site of the Big Island's Train Museum. At one time narrow-gauge railways carried sugar cane down the coast. The coastal railways were another victim of the tsunami. The coal that powered those trains was created by Earth's internal heat. Even the energy of a steam engine originated near the Big Bang.

Monday, January 15, 2007

Gemini North


Aloha! Sorry about the lighting. This is a control panel from the Gemini North telescope atop Mauna Kea. The weather is freezing! During the October 16 earthquake the telescope suffered a broken rod. The damage was quickly repaired and has been functioning since November 11. The telescope is a twin to Gemini South in Chile.

For the photo of Gemini below we can thank the neighbours, the Canada-France-Hawaii telescope. One dome of the Keck telescope is visible to the right. To the left are the lights of Hilo, which is much warmer.

Sunday, January 14, 2007

Ares IV


It pays to be flexible. NASA has quietly begun studies for ARES IV, which will combine 5-segment solid rocket boosters with the upper stage being developed for ARES I. The full stack is 113 m tall, taller than the 1960's Saturn V. This offers the promise of boosting a Lunar Lander to the Moon in one launch, without waiting for the CEV. The CEV would launch on a separate ARES IV and rendezvous in lunar orbit.

This also may be cheaper to develop than the ARES V. There is a risk that after ARES I is developed, funding will run out for ARES V and we will be stuck in low Earth orbit. NASA has budget issues, and is looking for something to cut. The Vision is top priority, so something else would have to go. NASA Chief Michael Griffin talked about this to AVIATION WEEK:

"I will do everything I can to keep Orion and Ares I on schedule," he says. "That will be right behind keeping shuttle and station on track, and then after that we'll fill up the bucket with our other priorities.

"The ideal candidate is a fairly new, lower priority effort where not a lot of money has already been invested, and by stopping it now you can react and not have to spend future money that you know you're not going to get," he says. "If we don't find the ideal candidate we'll look for less ideal candidates."

That sounds a lot like the Beyond Einstein Programme. The Joint Dark Energy Mission in particular has been getting by on funding from DOE, and is not considered a high priority. After years of work, they can not even agree on a concept. If funding for JDEM gets cut, supernova researchers have themselves to blame. UPDATE: DOE also faces a funding shortfall; what will they cut?

Saturday, January 13, 2007

Blowing Bubbles


Astronomer Rosa Williams gives us another photo from the Small Magellanic Cloud, an area known as LHa115-N19. Supernovae have created huge expanding bubbles. Three supernova remnants are in a process of merging, possibly to create one superbubble. The photo combines optical, infrared and radio data.

These voids in Space are not empty. At their centres are neutron stars, which can be visible as pulsars. Only through the loght of a pulsar does the central Black Hole reveal itself. As we have seen, larger voids between galaxies may not be empty either. Black Holes there would be massive enough to swallow any light.

The elements necessary for life are created in supernovae. The lightest elements, hydrogen and helium, were created in the first three minutes following the Big Bang. Heavier elements like carbon were made in the furnaces of the first stars. Supernova explosions create elements up to iron. Present theory can not account for elements heavier than iron. If the exploding stars are triggered by Black Holes, that would provide the necessary energy to create higher elements.

The elements for life are spread by these expanding bubbles throughout the galaxy, eventually reaching Earth's surface. Heavy radioactive elements like Uranium and Pottasium are only common in Earth's crust. Earth's core, the first part to form, contains mostly iron and nickel with no radioactive elements. Meteorites dating from the time of Earth's formation contain no radioactive elements. The idea of radiation keeping the core hot does not hold water. Something else has kept Earth's core warm and active.

Humans are just beginning to realise, most of the Universe is made of things they can't see. There is more to the Universe than meets the eye.

Friday, January 12, 2007

The Crusty Crab


A few months ago we saw spectacular video of the Crab supernova explosion. This new video shows the Crab pulsar imaged in X-rays by Chandra (blue) and in optical by the Hubble Space Telescope (red). The pulsar is a dynamic object with rings and jets of matter and anitmatter. The inner ring is about a light-year across.

Jennifer Ouelette has a nice post about history of the Crab. The pulsar's energy is focused on two twin jets. New observations announced at AAS tell us that the jets from are not quite symnetrical. The North jet is not the same as the South. Even before this new data, the very source of this immense energy was a mystery. "it's clear from these results," Jennifer writes, "the old bipole model just doesn't cut it."

The Crab is crusty from outer layers of pure neutrons, extremely dense and hard. A neutron star contains conditions that normal matter could not survive. What else could survive here? There is something even denser than neutrons. That object was there long before the Crab became a supernova, and even triggered the enormous explosion.

Neutrons spiralling into the Black Hole generate a huge amount of radiation. Spiralling charged particles produce a super-powerful magnetic field, forcing the escaping radiation into two jets. The Black Hole rotates independently of the pulsar, causing the two jets to exit away from the pulsar's rotation axis. The bright jets spin around like a police siren. As we have seen on Enceladus, the Northern and Southern jets would not be identical. Positively charged particles would be drawn into one jet and negatively charged particles would be drawn to the opposite jet. The combination of polar jets and a magnetic field is smoking gun evidence of a singularity.

Thursday, January 11, 2007

Kepler's Supernova


The Chandra X-ray observatory gave us this new view of SN 1604, discovered by Johannes Kepler. Once upon a time, supernova discoveries were so rare that you could name them by the year. Kepler studied at a number of universities, and was planning to be a minister when he was asked to take a teaching job. He would hold many jobs in his lifetime before becoming Tycho Brahe’s last assistant.

Tycho had discovered his own supernova in 1572. The king of Denmark gave Tycho funds and an island to build an observatory. Tycho’s many observations of planets provided Kepler with ample data to explore their motion. Kepler himself was known for his meticulous mathematical tables. Kepler believed, like Pythagoras, that mathematical relations underlie all of nature. Unlike Tycho, Kepler believed in the Copernican system, and sought to find a principle behind it.

For much of Kepler’s life, the Platonic solids fascinated him. These five shapes--tetrahedron, cube, octahedron, dodecahedron and icosahedron were known since at least the time of Pythagoras. Plato tried to relate them to the Earth and its elements. Kepler tried to explain orbits as ratios these solids, with only limited success. He had greater success with a theory of ellipses.

Starting from the principle of planets orbiting the Sun, Kepler came up with three laws:
1) Planetary orbits are elliptical with the Sun as one focus.
2) Orbits sweep out equal areas in equal amounts of time.
3) The period of a planetary orbit is proportional to its long axis raised to the 3/2 power.
These laws described the motion of planets far better than any epicycle theory. Kepler’s laws allowed him to predict the transit of Venus in 1631, providing a crucial proof. A full expalanation would come from Newton's gravity.

Galileo and Kepler kept up a correspondence. “Here at Padua,” Galileo complained in one letter, "is the principal professor of philosophy whom I have repeatedly and urgently requested to look at the moon and planets through my glass, which he pertinaciously refuses to do.” Even 400 years ago, learned minds literally refused to look at the truth. Today's cosmologists need to spend more time looking at nature. The truth can be quite beautiful.

UPDATE: New information indicates that Kepler's supernova was a Type Ia.

Wednesday, January 10, 2007

Magellanic Clouds


More from the AAS Meeting: A study using Hubble Space Telescope data has shown that the large and small Magellanic Clouds are moving twice as fast in relation to our galaxy as previously thought. Reesearchers took snapshots two years apart to measure their velocity against distant quasars. The Large Magellanic Cloud (left) is moving at 378 km/sec and the Small Magellanic Cloud (right) at 302 km/sec. This may indicate that our Milky Way is more massive than thought, similiar to how we discovered that "dark" mass exists. It could also indicate that the clouds are not gravitationally bound to the Milky Way.

This image is from Chile's Cerro Tololo Observatory. The clouds are only visible from Southern latitudes, so they were not discovered by Europenas until the time of Magellan. The Southern Sky holds many fascinating mysteries.

Pillars of Creation



More from the AAS meeting: Infrared observations suggest that the famous Eagle Nebula may be blown away by a nearby supernova. Not to worry, if so it will be visible in all its beauty for 1000 years. Here we see the process of star formation. The immense pillars are cocoons containing infant stars. Somehow the highly diffuse interstellar gas is collapsing into a point so hot and dense that nuclear fusion is ignited. During this process, something prevents that heat from dissipating the cloud and ending the birth.

One way to produce this formation would be if a tiny Black Hole, or many, collided with the cloud. Small singularities would naturally gather material around them, but would not be big enough to suck up the whole cloud. At their centres, gravity and Hawking radiation would produce the conditions for stars to ignite. The heat produced would balance gravity’s inward pull so that the stars burned steadily. The Black Holes may still be in the stars’ cores, quietly contributing to their power output.

Tuesday, January 09, 2007

Apple iPhone


Isn't this cool? The iphone will combine functions of a telephone, camera, computer and wireless device. They told me it will have desktop-like computing ability, meaning it can run most scientific functions. The 3.5 inch screen should make "Starry Night" very useful on observing nights.

Over 30 years ago Larry Niven and Jerry Pournelle wrote THE MOTE IN GOD'S EYE. The crew of their starship had pocket computers, which combined similiar functions in a pen-based device, with handwriting recognition. The iPhone uses an interactive touch screen, finger-based. Another Sci Fi dream come true. Now we must work on the starship. Talking computers like HAL would be nice too.

Monday, January 08, 2007

Little Galaxies Have Black Holes Too


From the American Astronomical Society Meeting in Seattle: A team represented by Victor Debattista from University of Washington has found a supermassive Black Hole at the centre of a dwarf galaxy. The galaxy VCC128 is 54 million light-years away in our Virgo Cluster, and has only 1% of our galaxy's mass. The team found the Black Hole by sifting through archival Hubble Space Telescope data. Their poster was presented Sunday, for these days even big discoveries are presented as posters.

The news in year 007 gets better and better. We saw just last week that, as predicted, globulars contain Black Holes. Dwarf galaxies are thought to develop from globular clusters. This supermassive Black Hole has a mass between 1 million and 50 million solar masses. In the right photo it is orbited by a ring of stars. "It had been speculated that dwarf galaxies like this could not make black holes," Debattista said. Perhaps the Black Hole was there before the galaxy.

Sunday, January 07, 2007

Dark Matter News


Another prediction of the book has come true.

Just the other day one prediction was verified, medium-sized Black Holes within galaxies. Today NATURE reports discovery of mass in regions previously thought to be empty voids. This map was produced by the Hubble Space Telescope's Cosmic Evolution Survey (COSMOS). The study used gravitational lensing to show where the mass really lies. Mass is measured by the contour lines, which do not line up with the visible matter.

"The existence of large clumps of isolated dark matter and visible matter flies in the face of everything we know," says cosmologist Carlos Frenk of the University of Durham, UK.

"There are plausible explanations for small areas of dark matter and visible matter existing in isolation," NATURE continues, "but these theories can't explain the large features visible on the COSMOS map."

Below are the next paragraphs from the book:

Astronomers Margaret Geller and John Huchra have been mapping galaxies since 1985. Today the Sloan Digital Sky Survey has mapped a slice of the visible Universe. Galaxies and clusters form enormous sheets stretching across millions of light-years. These great walls are boundaries of vast bubbles containing most of the Universe’s volume.

A fish in the Barrier Reef avoids dark holes in the coral, because they could hide something that could eat her! One hopes that humans are more intelligent than fish. It would be foolish to think that humans know everything in the Universe, or to assume that the “voids” are empty. Something may indeed be in those dark places, something hungrier and more massive than humans have imagined.

Theory predicts that quantum fluctuations near the time of the Big Bang could have created singularities of almost unlimited size. The largest would be true Black Holes devouring everything within reach. In the early Universe they would have cleared whole regions of matter. Models predict that about 71.62% of mass in the Universe would end up in such regions. Since the Cosmic Microwave Background dates from 380,000 years after the Big Bang, this majority of mass would not show up in the CMB. The fragile spaces in between, balanced in a tug-of-war between masses, would form sheets where galaxies could form. Magnified by expansion of the Universe, the picture would look exactly like what Sloan has seen.

Saturday, January 06, 2007

Supernovae Get Weirder


Observations of Type Ia supernovae are the only evidence of an "accelerating universe." It would be convenient for cosmologists if all Type Ia's were the same, all fireflies had the same luminosity, and all people thought the same. New evidence from the XMM-Newton and Chandra X-ray observatories may force a rethink.

The big photo is a composite of DEM L238 (right) and DEM L249. Chandra X-ray data is blue and optical data is red. The inset shows DEM L238 in low-energy (red), medium energy (green) and high energy X-rays (blue). The central portion of DEM L238 is hot and green, indicating an overabundance of iron.

Iron identifies DEM L238 as a Type Ia supernova. The iron in these supernovae is much denser than in most Type Ia's. That would indicate that the stars were born more massive and exploded as supernovae unusually young. They may represent an entirely new class of supernova.

Type Ia's are thought to result when a white dwarf star abruptly absorbs a companion, pushing it over the Chandrasekhar Limit of 1.4 solar masses. Boom! Chandrasekhar's Limit is proportional to hc/(Gm_p^2). Since the product hc is here considered constant, the limit is not affected by a changing c. Redshift and the energy E=mc^2 are affected, making the universe appear to accelerate.

Friday, January 05, 2007

Black Hole Found in Globular Cluster!


If any pleasure approaches that of scientific discovery, it can be found in the cockpit. Flying high above the Earth puts many problems in perspective. Cities at night are ablaze with a million lights. From experience we know that the pools of light are just a hint of the mass below. Between those lights are roads, buildings, and people going about their business. The majority of mass lies hidden in the darkness.

When they have nothing better to do, scientists speculate about multiple universes. Another Universe does exist, occupying the same Space/Time but hidden from our eyes. Theory predicts, and observations confirm, that the mass we can see is just 4.507034% of the total. To be aware of the other 95.49% is to be a seeing woman among the blind.

Globular cluster Messier 80 contains hundreds of thousands of stars orbiting our Milky Way. Astronomer Harold Shapley used observations of these objects to locate the galaxy’s centre. A globular cluster contains some of the oldest stars in our galaxy. Astronomers did not know how the globular clusters formed so early, or what holds them together. One way to form them would be from a medium-sized Black Hole captured by the Milky Way. Since this Black Hole formed primordially, it would have been a magnet for early star formation.

The prediction above was written some weeks ago, for a book yet to be published. With a nod to Kea, there is some wonderful news. BBC reports discovery of a medium-sized Black Hole inside a globular cluster! Obervations were made by ESA's XMM-Newton satellite with follow-up observations by the Chandra X-ray Observatory.

Astronomer Tom Maccarone said, "We were preparing for a long, systematic search of thousands of globular clusters with the hope of finding just one black hole. But bingo, we found one as soon as we started the search."

The Beeb continues: "Some models have suggested that large black holes - several hundred times the mass of our Sun - could develop in the densest inner regions of clusters. Other simulations, however, predict that such gravitational interplay would probably eject most or all of the black holes that form in such an environment."

One lesson is: Don't trust computer simulations! They are not nature. My computer says Lara Croft can fight with those boobs. It is now likely that every globular cluster contains a Black Hole.

The Black Hole is predicted to have been there before the globular cluster. It provided an anchor for the cluster to form. It is wonderful, wonderful to make a prediction that turns out to be true.

Quake Damage


The Hole in the Earth announced her presence to the Big Island last October 16. Recently I took a walk around Hilo looking for quake damage. Fortunately most of the damage was minor--a collapsed awning here, a lava rock wall there. The biggest loss is Mauna Kea Beach Hotel, closed indefinitely due to structural damage. About 420 people there will be out of work.

When a scientist gives a lecture people often ask, "what does cosmology have to do with us?" For every question like that there are many people who didn't attend for lack of interest. In fact, cosmology affects us every single day. A tiny remnant of the Big Bang causes earthquakes, volcanoes, and the magnetic field. Earth's singularity was created in the immense pressures and temperatures near the beginning of the Universe. The shaking felt October 16 was leftover energy from the Big Bang!

The angle below shows Kamehameha Avenue, the main oceanfront road. Yes, Hilo is rainy. The damage doesn't look so bad until you realise that there used to be buildings on the left side. A future post will talk about tsunamis.

Wednesday, January 03, 2007

Cosmology of Edgar Allen Poe

Kea and Dynamics of Cats are first to jump on the Year 007 bandwagon. A simple numerical expression can catch on quickly!

Harmonic oscillators are used all over physics. Here we salute the best harmonic oscillator story ever written, Edgar Allen Poe's THE PIT AND THE PENDULUM. Who can forget his description of the blade swinging closer and closer? In addition to his fiction, Poe was ahead of his time in cosmology!

In 1848 Poe published a 150-page prose called EUREKA, in which he speculated about cosmology. He was partly inspired by the mathematician Pascal, who wrote, "Nature is an infinite sphere of which the center is everywhere and the circumference nowhere." Like Pythagoras seeking harmony in spheres, Poe felt that a spherical universe was natural.

Most prescient, Poe suggested that this spherical universe expanded from a tiny point! "From the one particle. as a center, let us suppose to be irradiated spherically--in all directions--to immeasurable but still to definite distances in the previously vacant space." 75 years before Friedmann-Lemaitre, Edgar Allen Poe proposed an expanding universe!

Poe also adopted Pierre Laplace's "nebular hypothesis" that the solar system condensed from a gas cloud. He further proposed that the Milky Way orbits around a giant Central Orb. Since we can not see this massive object, Poe concluded it was a "non-luminous sun." He foresaw that our galaxy contains at its centre a massive Black Hole.

Poe also addressed Black Holes more directly. His story "A Descent Into the Maelstrom" describes a mysterious unseen object causing matter to spiral into it. EUREKA also contains a plausible solution to Olbers' Paradox. Not being a professional scientist, he preferred intuition to Aristotelian experiments. Despite his great works of poetry and fiction, Poe considered EUREKA his career masterpiece.

Yesterday we learned how Alexander Friedmann predicted an expanding universe. He may have been at partially inspired by EUREKA, for Friedmann was a huge fan of Poe. (Both men died at a young age.) Friedmann and Georges Lemaitre put the math into the expanding universe. Pascal, Einstein, even Edgar Allen Poe--if you think the universe is spherical you are in good company.

Tuesday, January 02, 2007

Friedmann Is In the Air Today


Thanks to Gebar and Kea for hints at putting equations on blogger.

Einstein in 1917 proposed a static universe, spherical with fixed radius. To prevent the sphere from collapsing due to its own gravitation, Einstein added a fudge factor, a cosmological constant. A spherical space would collapse UNLESS it were already expanding. An expanding universe would have been one of the greatest predictions ever, but Einstein rejected the idea.

Alexander Friedmann was born in St. Petersburg in 1888. His mother was a pianist, his father a ballet dancer and composer. While studying physics, he became interested in applications to meteorology. During the First World War, he volunteered to use his knowledge to aid the new tactic of aerial bombing. He flew as an observer on hazardous missions, becoming known to both sides. On days when Russian bombs were on-target, the Germans would mutter "Friedmann is in the air today."

After the war, despite the distraction of the revolution, Friedmann found solutions to Einstein's equations for an expanding Universe. His 1922 paper "On the Curvature of Space" is subtitled "to demonstrate the possibility of a world in which the curvature of space is independent of the three spatial coordinates but does depend on time." R is a multiple of t, R = ct. The universe needed no cosmological constant.

The Belgian priest Georges Lemaitre independently proposed an expanding universe as an explanation for redshifts. At a conference in 1927, he approached Einstein with the idea. The famous scientist could find no flaw with the math, but was uncomfortable with an expanding universe. Einstein had read the 1922 paper and wrongly thought Friedmann had made a mathematical error.

The Friedmann equations work both in units of mass density or energy density. First Friedmann equates kinetic and potential energies on the surface of an expanding sphere:
$\frac12 r^\prime$^2 = GM/r = $4 \pi G$r^2$\rho$(c^2)/3
($r^\prime$/r)^2 = $8 \pi G \rho$(c^2)/3
As we know, mass and energy are equivalent by E = m c^2.

Second we equate acceleration with gravitational attraction:
$r^\prime\prime$ = -GM/(r^2) = $-4 \pi G r \rho$(c^2)/3
$r^\prime\prime$/r = $-4 \pi G \rho$ (c^2)/3

Einstein gave us the field equation for gravitation:
$ R_{uv} - \frac12 g_{uv} R = \kappa T_{uv}$
The stress-energy tensor $T_uv$ (seen above) normally has units of energy density $\rho$(c^2).

We have seen that Einstein can be reduced to a form corresponding to Friedmann:
($r^\prime$/r)^2 - $\frac13 \kappa \rho$(c^2) = 0
($r^\prime\prime$/r) + $\frac16 \kappa \rho$(c^2) = 0

Removing, for a moment, the c^2 from Friedmann, we would have:
$8 \pi G \rho$/3 = $\frac13 \kappa \rho$ (c^2)
$4 \pi G \rho$/3 = $\frac16 \kappa \rho$ (c^2)

To normalise his left-hand with his right-hand sides, Einstein chose $ \kappa = 8 \pi G$/(c^2). This led to decades of misconception that Relativity requires a fixed c. Some "geometrized" unit systems give $ \kappa = 8 \pi G$/(c^4), which is too convoluted to describe. Since T_uv has units of energy density, we must use the same for Friedmann:
$8 \pi G \rho$(c^2)/3 = $\frac13 \kappa \rho$(c^2)
$4 \pi G \rho$(c^2)/3 = $\frac16 \kappa \rho$(c^2)
$\kappa = 8 \pi G$
This is very trivial. In earlier posts I've left out the (c^2) on both sides because it simply cancels out.

Now the Einstein equation is $ R_{uv} - \frac12 g_{uv} R = 8 \pi G T_{uv}$. The Bianchi identities become:
$\bigtriangledown {u} ( R_uv - \frac12 g_uv R ) = 0$
$8 \pi G \bigtriangledown {u} (T_uv) = 0$
The world is much simpler without that pesky (c^2) factor.

Finally, the Einstein-Hilbert action becomes:
$S = \int (16 \pi G R + L_m)$d^4(x)
Thus we can do everything General Relativity can without a fixed c. Some problems, like the deflection of bodies by the Sun, work even better with a varying c.

During the 1920's Edwin Hubble and Milton Humason used Cepheid Variables to show that the Universe expanded. In a 1931 visit to Mount Wilson, Einstein conferred with Hubble and peered through the telescope. Einstein dropped the cosmological constant, later calling it his "greatest blunder." He became one of Lemaitre's biggest supporters. If Einstein says the CC is a blunder it probably is a blunder.

Unfortunately, Friedmann had died in 1925 at the age of 37. He had continued his interests in weather and flying. After attempting a record-setting balloon flight, he contacted a fever. Inventing a Theory that makes real predictions (light is slowing down) runs the risk of being proved wrong. At first, even a great man like Einstein may think you have made an error. Whether challenging the air or contradicting Einstein, Alexander Friedmann was not afraid of taking risks.

Monday, January 01, 2007

Happy 007


Happy New Year! Here starts a movement to call this year 007, a la James Bond. That is something we only get to do once every 1000 years, and distinguishes this year from 1907 or 2107.

The Imiloa Astronomy Centre opened last year. It is located on the grounds of the University of Hawaii in Hilo, not far from the Institute for Astronomy. It provides a valuable educational resource for the island. Here you can learn about Hawaiian astronomy without climbing Mauna Kea.

Siting telescopes on our mountain has been controversial among islanders who consider it sacred ground. The Centre goes out of its way to include Hawaiian culture and how it is related to the stars. The outrigger canoe illustrates how Polynesian navigators used astronomy to reach the islands. Future shows may relate cosmology to the volcanoes which formed our islands. As you know, the Big Bang, Black Holes, volcanoes and Earth's formation are all tied together.
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