Month: April 2016

Design Within The Non Biological Realm

My central premise here is that you know design when you see it. You know design when in fact something is designed. But how do you know design when you see it? There are usually three criteria that assist you or that seem to apply here. The first is variety (both within the class of objects as well as within the object itself). If something non-living comes in a kind of a Heinz 57-variety selection, then perhaps design is at work. In addition, if any individual object is composed of a wide variety of components, then it stands a good chance it was designed. The second is symmetry. Objects that have symmetry seem to be more likely designed as not designed. The third is complexity. The greater the complexity the more likely there was a designer behind the complexity. Something that has variety, complexity and symmetry is highly likely to be designed*. For example:

DESIGNED

Ant Hills / Nests; Aztec / Mayan / Egyptian Pyramids; Bicycles (and related vehicles); Birds Nest; Furniture (i.e. – chairs, tables); DVDs / CDs; Electronic Goods and Equipment; Jewellery (i.e. – earrings, rings, bracelets); Easter Island Statues; Radio Telescopes; Rosetta Stone (and other inscribed tablets); Roundabouts; Rubik’s Cube; Rules / Laws; Skyscrapers (i.e. – Empire State Building); Swimming Pools; Sydney Harbour Bridge (and related structures); Television Sets; Units of Measurement; Watches / Clocks; and so on.

NOT DESIGNED

Clouds; Coastlines; Flames; Galaxies; Lakes / Ponds; Lightning Bolts; Mountains; Rivers / Streams; Salt Crystals (and related mineralogy**); and so on.

You probably wouldn’t consider any fundamental particle to be designed since, for example, an electron doesn’t come in a wide variety of types, nor is an electron in itself complex – an electron being absolutely elementary or fundamental, and an electron in and of itself doesn’t have symmetry with respect to its electric charge or ‘spin’. An atom of gold is an atom of gold is an atom of gold. You see one atom of gold, you’ve seen them all.

On the other hand, you could argue that there is a wide variety of different kinds of elementary particles with many symmetries between them and complex interactions between the lot, some of which result in atomic structures of which there are a wide variety of types (92 natural ones) and symmetries and complex interactions which result in molecules, and so on.

So what other non-living, non-human designed object do you think both has variety, symmetry and complexity? Well, what about planets and stars?

Variety

There’s quite a variety in the fine gradient from one (planets) through to another (stars). There’s no longer a fine sharp distinction between planets and stars. Gas giants (like Jupiter) morph into brown dwarfs which morph into low mass stars. Jupiter has often been called a “failed star” having not quite achieved enough mass to ignite stellar fusion. Still Jupiter ‘shines’ in the infra-red since it emits more energy than it actually receives from the Sun. Even Earth ‘shines’ in the infra-red due to the radiation of its internal heat.

In the stellar category itself we have lots of variety from quasars to black holes to neutron stars (pulsars) to variable stars to red giants, brown dwarfs, red dwarfs, white dwarfs, etc. Then too are all those distinctions and subdivisions made in the main sequence of stars which all astronomy students memorize as the pneumonic OBAFGKMRN (oh be a fine girl kiss me right now).

There’s lots and lots of planetary variety too, especially true when including the many moons that abound in orbit around them. You have planets with and without moons and with moons of all sizes some rivalling planets in size and complexity. Within those moons surrounding the Jovian planets, you have oceans of varying chemistries both with and without global icecaps.

Each and every planet (major and minor) is unique. You have your rocky terrestrial worlds with and without atmospheres and atmospheres both thick and thin and in-between. You’ve got in our solar system four gas giants and nobody, even laypersons even somewhat familiar with planetary astronomy has any trouble telling them apart. In fact a strong argument could be made that Jupiter and Saturn are the two most picturesque of the planets – the jewels of the solar system.

Now add in all of the variety discovered to date in extra-solar planets, like ‘hot Jupiters’.

In addition, each star and planet in and of itself exhibits much internal variety from boundary to core as any cross-section illustrated in textbooks makes clear.

Symmetry

There is lots of types of symmetry in stars and planets. There would be north-south symmetry at least with respect to planetary atmospheres – terrestrial and Jovian (the gas giants) as well as stellar atmospheres. There are layered symmetries as in – using Earth as an example – atmosphere (itself divided into layers), crust, mantle, outer core, and inner core.

Our own solar system can rival in complexity and symmetries anything that humans have designed.

Complexity

In both stars and planets you have the full complement, repertoire, operation of physics (micro and macro) and chemistry (with the exception for my purposes here of biochemistry as I’m assuming a lifeless Universe) with all associated forces and fields in play.

Both planets and stars are multi-layered with complex interactions generating for example magnetic fields, auroras, and climatic systems.

In general there would be complex inter land / sea / air interactions as well as complex intra interactions within the land (lithosphere), sea (hydrosphere) and air (atmosphere).

Even without life, Planet Earth would exhibit complex recycling systems. There would still be a water cycle. There would still be rock recycling via plate tectonics. There would still be a carbon cycle, or rather a carbon dioxide cycle.

The carbon dioxide cycle would be such that terrestrial volcanoes and the weathering of rocks would release carbon dioxide and carbon dioxide would be incorporated by dissolving into the chemistry of the oceans ultimately precipitated or incorporated into marine sediments which ultimately get converted into rock.

If it wasn’t for the fact that we’ve seen them, would we humans been able to mentally alone conceive of comets? Even having mastered all of physics and chemistry, could the human mind have conceived of a Jupiter or Saturn, Titan or Venus, had they not already presented themselves to us?

As we’ve explored the solar system the unexpected has come to be the expected. Volcanoes on Io (a moon of Jupiter) and an ocean (under the ice) on Europa (another moon of Jupiter) and hydrocarbon lakes and methane rain on Titan (a satellite of Saturn) are examples in point.

Then there’s that odd coincidence (?) that only the Earth-Moon-Sun configuration produces solar eclipses in our Solar System. The Moon might be 400 times smaller than the Sun but the Sun is 400 times farther away and so the face of the Moon can just block out the face of the Sun producing solar eclipses for our ‘enjoyment’ as well as for astronomers to conduct astronomical research into solar physics and special relativity as well.

Now I’m well aware that astronomers, both stellar and planetary can explain nearly all of the above by naturalistic means – albeit that doesn’t mean that unexplained (to date) anomalies don’t still exist. Still, stars and planets collectively have all of the ingredients of a master painting on a cosmic canvas.

*That’s not to say that some non-designed things can have lots of variety (like clouds), or symmetry (like volcanoes), or complexity (climate), it’s just that non-designed objects don’t tend to exhibit all three criteria. Clouds aren’t overly symmetrical or complex. Volcanoes don’t have a great deal of variety and aren’t overly complex. Climate may exhibit some variety (albeit not really that much) but doesn’t have much symmetry accorded to it.

Further, non-designed elements can be incorporated into something designed, like natural rocks can be incorporated into a wall, or a rock garden or even a house. Or, non-designed elements might emerge naturally from what has been designed. Taking planets and stars for example, the Great Red Spot (of Jupiter) or terrestrial clouds or solar flares might emerge naturally and un-designed from the design itself. Expect the unexpected!

**Snowflakes might seem an exception having great symmetry and great variety, but they aren’t all that complex being composed on only one type of molecule.

The Mystery Of The Migrating Roaster Planets

The last decade has seen the discovery of a treasure trove of exoplanets. Indeed, almost 2,000 of these distant, alien planets, that belong to the families of stars beyond our own Sun, have been confirmed–so far! Many of these distant, exotic worlds belong to a strange class termed hot Jupiters, which are gas-giants like our own Solar System’s behemoth Jupiter, but are much hotter because they sport orbits that carry them within a “roasting” distance of their fiery stellar parents. But as common as hot Jupiters are thought to be, their formation history is still heavily shrouded in mystery–how did these gigantic, roasting worlds manage to get so close to their searing-hot and roiling parent-stars? That is the question! In March 2016, a team of astronomers using NASA’s infrared Spitzer Space Telescope (SST), announced that they have found an answer to this intriguing riddle.

When the very first batch of hot Jupiters were discovered a generation ago, they were generally considered to be “oddballs” because we do not have anything like them in our Sun’s family. However, as more and more of these exotic and very distant worlds were spotted over the last two decades (along with many other smaller exoplanets that also hug their parent-stars fast and close in roasting orbits), our Solar System began to look like the real oddity.

“We thought our Solar System was normal, but that’s not so much the case,” commented Dr. Greg Laughlin in a March 28, 2016 NASA Jet Propulsion Laboratory (JPL) Press Release. Dr. Laughlin is an astronomer at the University of California, Santa Cruz, and co-author of the new SST study that investigates hot Jupiter formation. The study has been accepted for publication in The Astrophysical Journal Letters.

How did these weird and exotic worlds wind up so meltingly close to their searing-hot parent-star?

The SST found new clues by watching a hot Jupiter dubbed HD 80606 b, situated about 190 light-years from our planet. This brave new world is weird because it has a wildly eccentric orbit that resembles that of a comet, swinging it very close to its parent-star, and then hurling it out again to a considerably greater distance repeatedly every 111 days. One side of this “oddball” is thought to become dramatically hotter than the other as the tortured world closely approaches its star. Indeed, when the hot Jupiter is closest to its stellar-parent, the side facing the star rapidly reaches a broiling temperature of over 2,000 degrees Fahrenheit.

“As the planet gets closer to the star, it feels a burst of starlight, or radiation. The atmosphere becomes a cauldron of chemical reactions, and the winds ramp up far beyond hurricane force,” Dr. Laughlin continued to explain.

Searing Hot Denizens Of The Exoplanet Zoo

Ever since the historic discovery of the first exoplanet a generation ago, planet-hunting astronomers have been detecting a previously hidden treasure of wild, weird, and wonderful faraway worlds. Some of these distant worlds display an almost eerie likeness to the familiar planets in our own Solar System–while others are so different that they appear intriguingly bizarre.

Hot Jupiters hug their parent stars closely, circling them in roasting hell-like orbits–with a “year” lasting only a few days. Sometimes alternatively termed roaster planets, epistellar jovians, pegasids, or pegasean planets, these weird worlds were some of the first to be discovered. This is because they are the easiest planets to detect using the radial-velocity method, which was the first method used to successfully spot exoplanets. The radial-velocity method detects the oscillations that these planets induce in their parent-stars’ motions, and the relatively large and rapid motions induced by close-in giant planets in tight orbits are the easiest planets to detect using this technique. One of the most famous hot Jupiters is 51 Pegasi b, which was discovered in 1995, and it was the first exoplanet to be discovered in orbit around a main-sequence (hydrogen-burning) Sun-like star. 51 Pegasi b sports an orbital period of about 4 days. This first discovery of a hot Jupiter surprised planet-hunting astronomers who did not think that such close-in, giant, gaseous worlds could exist. The mystery surrounding this exotic form of exoplanet has plagued the astronomical community for over twenty years.

As of April 2, 2016, 2,107 exoplanets have been discovered and confirmed, dwelling within 1349 planetary systems, including 511 multiple planetary systems. In addition, there are free-floating “orphan” exoplanets that are not bound to any parent-star at all, but instead travel as solitary objects through the space between stars, without the comforting companionship of a stellar parent or planetary siblings. Alas, once these planetary “orphans” were members of a system, but they were booted out of their home as a result of the gravitational bullying of sibling planets, that cast them out into the cold, to travel lost and lonely through the darkness of interstellar space.

Even though the discovery of thousands of alien planets has become “business as usual” for astronomers on the hunt for these distant worlds, this has not always been the case. Indeed, the search for planets belonging to the families of stars beyond our own Sun, historically proved to be a difficult endeavor–and often quite frustrating. At long last, in 1992, the very first batch of truly weird exoplanets were spotted circling a small, dense, and rapidly spinning stellar corpse called a pulsar. Dr. Alexander Wolszczan of Pennsylvania State University, after carefully watching radio emissions emanating from a compact millisecond pulsar with the colorless name of PSR B1257 + 12, made the historic determination that it was being orbited by several extraordinarily bizarre small worlds. A pulsar is only about 12 miles in diameter–and it is really the collapsed core of what was once a massive main-sequence star on the Hertzsprung-Russell Diagram of stellar evolution. This strange, dense, small stellar ghost is the leftovers of a star that has burned its necessary supply of hydrogen fuel, and has perished in the fiery explosion of a supernova blast.

In 1995, 51 Pegasi b was discovered in orbit around a normal star. This historic discovery was first made by Dr. Michel Mayor and Dr. Didier Queloz of Switzerland’s Geneva Observatory, and soon confirmed by American planet-hunting astronomers using the Lick Observatory’s three-meter telescope poised atop Mount Hamilton in California.

New theories were promptly devised to explain these very strange hot Jupiters. Some astronomers suggested that these bizarre “roasters” were huge molten rocks; while others proposed that they were gas-giant planets born about 100 times farther away from their parent-stars. According to this latter theory, hot Jupiters were tragically hurled back towards their stellar-parent as a result of near-collisions with other sibling worlds, or possibly even a binary companion of their own star.

One theory proposes that hot Jupiters are born at a distance from their star that is comparable to that of our own Solar System’s Jupiter around our Sun–but then they slowly lose energy as a result of interactions with the protoplanetary accretion disk, composed of gas and dust, from which they formed. The neonatal giant, as a result, spirals into the well-lit and hot inner regions of its planetary system, far from its colder and more remote birthplace.

Hot-Jupiters may well be doomed giants, destined to experience a violent, fiery death within the furious furnaces of their glaring parent-stars. However, until that final, fatal moment, these unlucky “roasters” circle their stars fast and close–and they are very, very hot!

Actually, hot Jupiters are a diverse bunch. However, they do share certain defining properties:

–They possess large masses and brief orbital periods.

–Most have almost circular orbits.

–Many have unusally low densities.

–They likely harbor exotic, extreme atmospheres as a result of their short periods, relatively long days, and tidal locking.

–They appear to be more prevalent around F- and G-type stars, but less so around K-type stars. They are rarely found circling red dwarf stars. Red dwarfs are the smallest of true stars, as well as the most abundant type of star in our Milky Way Galaxy.

The prevailing view among astronomers is that hot Jupiters form further away from their star, and then migrate inward.

Our Galaxy’s Hidden Heart Reveals Its Ancient Secrets

Our Milky Way Galaxy is very old. Indeed, at 13.21 billion years of age, it is almost as old as the 13.8 billion year old Universe itself, which was born in the wild exponential inflation of the Big Bang. In fact, the oldest stars inhabiting our Galaxy were likely part of the brilliant stellar fireworks display that brought to an end the strange Cosmic Dark Ages–the era that occurred soon after the Big Bang when our Universe was a featureless swath of barren darkness. Today, we can observe our Galaxy as a fuzzy band of white light that stretches across the night sky, from horizon to horizon, like an upside down smile, reminding us that we are only a small part of something else–something vast, mighty, and mysterious. In April 2016, an international team of astronomers announced they have discovered that the central 2,000 light-years within our Galaxy hosts a population of primordial stars that are more than 10 billion years old–and their orbits in space preserve the ancient long-lost story of our Milky Way’s birth.

When we look up at the sky on a clear midnight, we see that it has been set on fire by the furious, faraway flames of billions and billions of sparkling stars. Our Milky Way Galaxy, that contains our Solar System, was given its name because of its appearance as a faint glowing band stretching across this midnight sky, whose stars cannot be distinguished as individual objects by the naked eye. The term “Milky Way” is a translation from the Latin via lactea, and from the Greek “milky circle”. From our planet, our Galaxy appears as a band because its disk-shaped structure is being observed from within. The great Italian astronomer Galileo Galilei first resolved this glowing, fuzzy band of light into individual stars with his telescope in 1610.

Until the early 1920s, most astronomers believed that our Galaxy contained all the stars dwelling in the Universe–in fact, they thought that our Galaxy was the entire Universe! However, following closely on the heels of the 1920 Great Debate between the two American astronomers Harlow Shapley (1885-1972) and Heber Curtis (1872-1942), came the historic discoveries of the American astronomer Edwin Hubble. Hubble, the “father of modern observational astronomy”, was able to demonstrate that our Milky Way is really only one of billions of galaxies. Indeed, it is now estimated that the number of galaxies dancing around in our observable Universe could be as great as 200 billion.

The Great Debate centered on the identity of spiral nebulae. The main issue of the debate was whether these distant nebulae were really relatively small objects that inhabited the outer limits of our Milky Way, or whether they were independent galaxies in their own right. Edwin Hubble–after whom the Hubble Space Telescope is named–settled the issue once and for all. Our Galaxy is not the entire Universe.

Our Milky Way is a large barred-spiral galaxy that sports an impressive diameter that is usually estimated to be approximately 100,000 to 120,000 light-years–but it may be as much as 150,000 to 180,000 light-years. Our Galaxy is also thought to host an estimated 100 to 400 billion stars, although this stellar number may really be as high as one trillion. In addition, there very well may be at least 100 billion planets inhabiting our Galaxy.

Our Sun, and its familiar family of planets, moons, asteroids, and comets, are all located within the Galactic disk, approximately 27,000 light years from our Milky Way’s secretive heart, or core. Our entire Solar System is situated on the inner edge of one of our Galaxy’s spiral-shaped collections of gas and dust named the Orion Arm. The stars that inhabit the inner 10,000 light-years, or so, form a bulge. Also, one or more bars radiate outward from this bulge. At the very center of our Milky Way, there lurks a powerful radio source, named Sagittarius A* (Sagittarius-a-star), which is likely a supermassive black hole that weighs-in at millions of suns.

The stars and gases at a variety of distances from the Galactic Center all orbit at about 220 kilometers per second. The constant rotation speed is at odds with the Keplerian laws of dynamics, and so it suggests that much of the mass of our Galaxy does not emit or absorb electromagnetic radiation. This mass is thought to be composed of the dark matter, which is a bizarre substance theoretically composed of exotic non-atomic particles that do not interact with visible light or any other form of electromagnetic radiation. It is generally thought that the dark matter accounts for most of the material content of the Universe.

The period of rotation is approximately 240 million years at the position of our Solar System. As a whole, our entire Galaxy is traveling at a speed of 600 kilometers per second with respect to extragalactic frames of reference. Our Milky Way’s center is located in the direction of the constellations Sagittarius, Scorpius, and Ophiuchus–where it appears brightest. The most ancient stars in our Milky Way likely ignited soon after the cosmological Dark Ages came to an end.

Our Galaxy has several galactic satellites and is a member of the Local Group of galaxies, which is itself a constituent of the Virgo Cluster–which is itself a component of the immense Laniakea Supercluster.

The Milky Way’s Heart

Because of interstellar dust, swirling smoke-like along the line of sight, the Galactic Center cannot be observed at visible, ultraviolet or soft X-ray electromagnetic wavelengths. Therefore, the information available to explain the Galactic Center is derived from observations at gamma ray, hard X-ray, infrared sub-millimeter and radio wavelengths.

Shapley noted in 1918 that he believed the halo of globular clusters circling around our Milky Way appeared to be centered on the stellar swarms in the constellation Sagittarius. However, giant, frigid, dark–and beautifully eerie– molecular clouds, haunting the area, shrouded the view for frustrated optical astronomers. In the first decades of the 1940s, the German astronomer Walter Baade (1893-1960) of the California Institute of Technology, in Pasadena–where he did his most important work–took advantage of World War II blackout conditions in nearby Los Angeles to go on the hunt for the center of our Galaxy. To accomplish this, Baade used the 100 inch Hooker Telescope at Mount Wilson Observatory, and spotted a one-degree-wide void in the interstellar dust lanes near the star dubbed Alnasl (Gamma Sagittarii)–providing a clear window through the spiral arms of our Milky Way to the swarms of sparkling stars surrounding its nucleus. The gap has been known as Baade’s Window ever since. Nevertheless, Baade was not convinced that he really had located the Galactic Center, and when the Mount Palomar Telescopes in California were commissioned around 1950, he went on to use them for additional searches for this Galactic holy grail–but with no success.

In the 1970s, a team of Australian astronomers from the Division of Radiophysics at the Commonwealth Scientific and Industrial Research Center (CSIRO), led by Dr. Joseph Lade Pawsey, used what they called a “sea interferometer” to detect some of the first interstellar and intergalactic radio sources. By 1984, they had successfully constructed an 80-foot fixed radio dish antenna, and had used it to conduct a detailed study of an extremely powerful extended belt of radio emission spotted within Sagittarius. The astronomers named a particularly intense point-source, near the center of this belt, Sagittarius A and realized that it was situated at the very center of our Galaxy–despite being about 32 degrees south-west of the conjectured Galactic Center of the time.

A study conducted back in 2008, using the Very Long Baseline Interferometer (VLBI), that links radio telescopes in Arizona, California, and Hawaii, measured the diameter of an especially intense compact radio source, Sagittarius A*, located within Sagittarius A–which coincides with a supermassive black hole at the very heart of our Galaxy. Accretion of gas onto our Milky Way’s resident supermassive black hole, probably involving a glaring disk circling it, would emit energy to power the radio source–which itself is considerably larger than the black hole. The black hole itself is too small to be observed with today’s instruments.

The 2008 study measured the diameter of Sagittarius A* to be 44 million kilometers. As a comparison, the radius of our planet’s orbit around the Sun is about 150 million kilometers, whereas the distance of Mercury from our Sun at closest approach is 46 million kilometers. Therefore, the diameter of the radio source is only slightly less than the distance of Mercury from our Star.

Astronomers at the Max Planck Institute for Extraterrestrial Physics in Germany have confirmed the existence of a supermassive black hole at the heart of our Galaxy, that is about 4.3 million times the mass of our Sun.

Our Galaxy’s Hidden Heart Reveals Its Ancient Secrets

In April 2016, the team of international astronomers announced that they had kinematically disintangled the primordial component of our Galaxy’s hidden heart for the very first time–separating its stellar population from the stars that currently dominate the mass of our Milky Way. Using the AAOmega spectrograph on the Anglo Australian Telescope near Siding Spring, Australia, the astronomers focused on a very ancient and well-known class of stars, termed RR Lyrae variables. RR Lyrae variables pulsate in brightness approximately once daily, which makes them more difficult to observe than their non-pulsating stellar siblings. However, RR Lyraes have the definite advantage of being standard candles. In astronomy, standard candles are astrophysical objects, such as variable stars like RR Lyrae, which possess a known luminosity as a result of some characteristic quality possessed by the entire class of objects. Therefore, if a distant celestial object can be identified as a standard candle, then the absolute magnitude (luminosity) of that object is known. By knowing the absolute magnitude, astronomers can calculate the distance from the apparent magnitude.

RR Lyrae stars enable astronomers to make precise distance estimates. These variable stars are found only in ancient stellar populations that are about 10 billion years old, and inhabit primordial halo globular clusters. Globular clusters are collections of stars that orbit around the core of a galaxy as satellites. Tightly bound together by gravity, they are pulled together by this force into spherical shapes, and have relatively high stellar densities toward their centers.

The velocities of hundreds of stars were simultaneously obtained by the astronomers, who observed them in the direction of the constellation Sagittarius over an area of the sky larger than the full Moon. As a result, the scientists were able to use the age of these stars to explore the environment in the central part of our Milky Way when it was first forming.

Our Galaxy hosts multiple generations of stars that span the time from its ancient formation to the present. Because heavy atomic elements are cooked up in the searing-hot hearts of stars, younger stellar generations become the recipients of the metals formed in the furnaces of previous generations of stars. In this way, successive stellar generations become increasingly rich in heavy metals that were formed in the hot hearts of older generations. All of the atomic elements heavier than helium, that are listed in the familiar Periodic Table, are called metals by astronomers. The Big Bang produced only the lightest of atomic elements–hydrogen, helium, and traces of lithium and beryllium (Big Bang nucleosynthesis). All of the atomic elements heavier than helium were manufactured in the seething-hot flames of the stars by way of the process of nuclear fusion–or, alternatively, in the fatal supernovae blasts of the more massive stars when they perished in these explosive stellar tantrums. In the intense and powerful fires raging in the hot hearts of the stars, increasingly heavier and heavier atomic elements are fused from lighter ones (stellar nucleosynthesis).

Therefore, the term metal, in the jargon of astronomers, carries a different meaning than the same term when it is used by chemists. Metallic bonds are absolutely impossible in the extremely hot cores of stars, and the very strongest of chemical bonds are only possible in the outermost layers of the coolest of sub-stellar objects, such as brown dwarfs. Brown dwarfs are stellar failures, and are not even stars in the strictest sense because, even though it is commonly thought that they are born in the same way as normal stars, they are much too small for their nuclear-fusing furnaces to ignite.

The metallicity of a star provides a precious tool for astronomers to use because its determination can reveal the star’s age. The oldest stars, designated Population III, were depleted of metals because there had been no previous generation of stars to produce them. Population I stars, like our Sun, represent the youngest stellar generation, and have been gifted with the metals that had been produced by earlier generations of stars. Population II stars are very ancient–but not as ancient as Population III stars. However, Population II stars are much older than Population I stars like our Sun, and they carry the metals manufactured in the hot hearts of Population III stars–but they do not contain the higher metal content of stars like our Sun. Nevertheless, Population II stars possess very low metallicities.

A Moon For Makemake

A Moon For MakemakeImagine, a frigid, distant shadow-region in the far suburbs our Solar System, where a myriad of twirling icy objects–some large, some small–orbit our Sun in a mysterious, mesmerizing phantom-like ballet within this eerie and strange swath of darkness. Here, where our Sun is so far away that it hangs suspended in an alien sky of perpetual twilight, looking just like a particularly large star traveling through a sea of smaller stars, is the Kuiper Belt–a mysterious, distant deep-freeze that astronomers are only now first beginning to explore. Makemake is a denizen of this remote region, a dwarf planet that is one of the largest known objects inhabiting the Kuiper Belt, sporting a diameter that is about two-thirds the size of Pluto. In April 2016, a team of astronomers announced that, while peering into the outer limits of our Solar System, NASA’s Hubble Space Telescope (HST) discovered a tiny, dark moon orbiting Makemake, which is the second brightest icy dwarf planet–after Pluto–in the Kuiper Belt.

The tiny moon–which for now has been designated S/2015 (136472) 1, and playfully nicknamed MK 2, for short–is more than 1,300 times dimmer than Makemake itself. MK 2 was first spotted when it was about 13,000 miles from its dwarf planet parent, and its diameter is estimated to be about 100 miles across. Makemake is 870 miles wide, and the dwarf planet, which was discovered over a decade ago, is named for the creation deity of the Rapa Nui people of Easter Island.

Discovered on March 31, 2005, by a team of planetary scientists led by Dr. Michael E. Brown of the California Institute of Technology (Caltech) in Pasadena, Makemake was initially dubbed 2005 FY 9, when Dr. Brown and his colleagues, announced its discovery on July 29, 2005. The team of astronomers had used Caltech’s Palomar Observatory near San Diego to make their discovery of this icy dwarf planet, that was later given the minor-planet number of 136472. Makemake was classified as a dwarf planet by the International Astronomical Union (IAU) in July 2008. Dr. Brown’s team of astronomers had originally planned to delay announcing their discoveries of the bright, icy denizens of the Kuiper BeltMakemake and its sister world Eris–until additional calculations and observations were complete. However, they went on to announce them both on July 29, 2005, when the discovery of Haumea–another large icy denizen of the outer limits of our Solar System that they had been watchingwas announced amidst considerable controversy on July 27, 2005, by a different team of planetary scientists from Spain.

Although the provisional designation of 2005 FY9 was given to Makemake when its discovery was made public, before that Dr. Brown’s team had used the playful codename “Easter Bunny” for this small world, because of its discovery shortly after Easter.

Makemake is about a fifth as bright as Pluto. However, despite its comparative brightness, it was not discovered until well after a number of much fainter KBOs had been detected. Most of the scientific hunts for minor planets are conducted relatively close to the region of the sky that the Sun, Earth’s Moon, and planets appear to lie in (the ecliptic). This is because there is a much greater likelihood of discovering objects there. Makemake is thought to have evaded detection during earlier searches because of its relatively high orbital inclination, as well as the fact that it was at its greatest distance from the ecliptic at the time of its discovery–in the northern constellation of Coma Berenices.

The Kuiper Belt

Dark, distant, and cold, the Kuiper Belt is the remote domain of an icy multitude of comet nuclei, that orbit our Sun in a strange, fantastic, and fabulous dance. Here, in the alien deep freeze of our Solar System’s outer suburbs, the ice dwarf planet Pluto and its quintet of moons dwell along with a cornucopia of others of their bizarre and frozen kind. This very distant region of our Star’s domain is so far from our planet that astronomers are only now first beginning to explore it, thanks to the historic visit to the Pluto system by NASA’s very successful and productive New Horizons spacecraft on July 14, 2015. New Horizons is now well on its way to discover more and more long-held secrets belonging to this distant, dimly lit domain of icy worldlets.

The Kuiper Belt is situated beyond the orbit of the beautiful, blue, and banded giant gaseous planet, Neptune–the outermost of the eight major planets of our Sun’s family. Pluto is a relatively large inhabitant of this region, and it was–initially–classified as the ninth major planet from our Sun after its discovery by the American astronomer Clyde Tombaugh (1906-1997) in 1930. However, the eventual realization among astronomers that the frozen little “oddball” that is Pluto, is really only one of numerous other icy bodies inhabiting the Kuiper Belt, forced the IAU to formally define the term “planet” in 2006–and poor, pitiful Pluto lost its lofty designation of “major planet” only to be re-classified as a mere minor one–a demoted dwarf planet.

Comets are actually bright, streaking invaders from far, far away that carry within their mysterious, frozen hearts the most pristine of primordial ingredients that contributed to the formation of our Solar System about 4.6 billion years ago. This primeval mix of frozen material has been preserved in the pristine “deep-freeze” of our Solar System’s darkest, most distant domains. Comets are brilliant and breathtaking spectacles that for decades were too dismissively called “dirty snowballs” or “icy dirt balls”, depending on the particular astronomer’s point of view. These frozen alien objects zip into the inner Solar System, where our planet is situated, from their distant home beyond Neptune. It is generally thought that by acquiring an understanding of the ingredients that make up these ephemeral, fragile celestial objects, a scientific understanding of the mysterious ingredients that contributed to the precious recipe that cooked up our Solar System can be made.

Comets are really traveling relic icy planetesimals, the remnants of what was once a vast population of ancient objects that contributed to the construction of the quartet of giant, gaseous planets of the outer Solar System: Jupiter, Saturn, Uranus, and Neptune. Alternatively, the asteroids–that primarily inhabit the region between Mars and Jupiter termed the Main Asteroid Belt–are the leftover rocky and metallic planetesimals that bumped into one another and then merged together to form the four rocky and metallic inner planets: Mercury, Venus, Earth, and Mars. Planetesimals of both the rocky and icy kind blasted into one another in the cosmic “shooting gallery” that was our young Solar System. These colliding objects also merged together to create ever larger and larger bodies–from pebble size, to boulder size, to mountain size–and, finally, to planet size.

Brilliant, icy short-period comets invade the bright and toasty inner Solar System, far from their frozen domain in the Kuiper Belt. The Kuiper Belt is the reservoir of comet nuclei that is located closest to Earth. Short-period comets rampage into the inner Solar System more frequently than every 200 years. The more distant long-period comets streak into the inner Solar System’s melting warmth and comforting light every 200 years–at least–from the Oort Cloud. Because Earth dwells closer to the Kuiper Belt than to the Oort Cloud, short-period comets are much more frequent invaders, and have played a more important part in Earth’s history than their long-period kin. Nevertheless, Kuiper Belt Objects (KBOs) are sufficiently small, distant, and dim to have escaped the reach of our scientific technology until 1992.

Makemake is a classical KBO. This means that its orbit is situated far enough away from Neptune to remain in a stable stage over the entire age of our more than 4 billion year old Solar System. Classical KBOs have perihelia that carry them far from the Sun, and they are also peacefully free from Neptune’s perturbing influence. Such objects show relatively low eccentricities and circle our Star in a way that is similar to that of the major planets. However, Makemake is a member of what is referred to as a “dynamically hot” class of classical KBOs, which instead display a high inclination when compared to other classical KBOs.

Makemake, like Pluto, shows a red hue in the visible part of the electromagnetic spectrum. The near-infrared spectrum is marked by the existence of the broad methane absorption bands–and methane has also been observed on Pluto. Spectral analysis of Makemake’s surface shows that its methane must be present in the form of large grains that are at least one centimeter in size. In addition to methane, there appears to be large quantities of ethane and tholins as well as smaller quantities of ethylene, acetylene, and high-mass alkanes (like propane)–most likely formed as a result of the photolysis of methane by solar radiation. The tholins are thought to be the source of the red color of the visible spectrum. Even though there is some evidence for the existence of nitrogen ice on Makemake’s frozen surface, at least combined with other ices, it is probably not close to the same abundance of nitrogen seen on Pluto and on Triton. Triton is a large moon of the planet Neptune that sports a retrograde orbit indicating that it is a captured object. Many astronomers think that Triton is a wandering refugee from the Kuiper Belt that was captured by the gravity of its large, gaseous planet. It is possible that eventually the doomed Triton will plunge into the immense, deep blue world that it has circled for so long as an adopted member of its family. Nitrogen accounts for more than 98 percent of the crust of both Pluto and Triton. The relative lack of nitrogen ice on Makemake hints that its supply of nitrogen has somehow been depleted over the age of our Solar System.

It was on April 26, 2016, that the team of astronomers, using observations from the HST taken in April 2015, announced their discovery of the small, dark 160-kilometer moon circling Makemake at a distance of 21,000 kilometers. The Kuiper Belt is the frigid twilight home of several known dwarf planets, and some of these distant icy worlds have known moons–however the moon that belongs to Makemake marks the first discovery of a companion object to Makemake. Makemake is one of the quintet of dwarf planets recognized by the IAU.

A Moon For Makemake

The observations of April 2015, that unveiled Makemake’s tiny moon, were made with HST’s Wide Field Camera 3. HST’s ability to observe faint objects close to bright ones, along with its sharp resolution, enabled the astronomers to spot the moon that was being masked by Makemake’s glare. The announcement of the dim little moon’s existence was made on April 26, 2016 in a Minor Planet Electronic Circular.

The team of astronomers used the same HST technique to observe the little moon as they did for discovering the small moons of Pluto in 2006, 2011, and 2012. Several earlier hunts around Makemake had not succeeded in spotting it. “Our preliminary estimates show that the moon’s orbit seems to be edge on, and that means that often when you look at the system you are going to miss the moon because it gets lost in the bright glare of Makemake,” commented Dr. Alex Parker in an April 28, 2016 Hubble Press Release. Dr. Parker, who led the image analysis for the observations, is of the Southwest Research Institute in Boulder, Colorado.

The discovery of a moon can lead to a treasure chest filled with valuable information about the dwarf-planet system. This is because, by measuring the moon’s orbit, astronomers can then go on to calculate a mass for the system and gain an important insight into its evolution.

Discovering the little moon also reinforces the theory that most dwarf planets have moons.

“Makemake is in the class of rare Pluto-like objects, so finding a companion is important. The discovery of the moon has given us an opportunity to study Makemake in far greater detail than we ever would have been able to without the companion,” Dr. Parker continued to explain.

The discovery of Makemake’s little moon increases the parallels between Pluto and Makemake. This is because both of the small icy worlds are already known to be well-coated in a frozen shell of methane. Furthermore, additional observations of the little moon will readily reveal the density of Makemake–an important result that will indicate if the bulk compositions of Pluto and Makemake are similar. “This new discovery opens a new chapter in comparative planetology in the outer Solar System,” Dr. Marc Buie commented in the April 26, 2016 Hubble Press Release. Dr. Buie, the team leader, is also of the Southwest Research Institute.

However, the astronomers will require more HST observations in order to obtain accurate measurements in order to determine if the moon’s orbit is circular or elliptical. Preliminary estimates suggest that if the moon is in a circular orbit, it finishes a circle around Makemake in 12 days or longer.

Determining the shape of the moon’s orbit will help resolve the question of its mysterious origin. A tight circular orbit would indicate that MK 2 is likely the result of a collision between Makemake and another KBO. Conversely, if the moon is in a wide, elongated orbit, it is more likely to be a captured object from the Kuiper Belt. In either case, the event would have probably occurred several billion years ago, in our primeval Solar System.

The discovery of a moon for Makemake may have solved one perplexing puzzle concerning this distant, icy object. Earlier infrared studies of the dwarf planet showed that while Makemake’s surface is almost entirely frozen and bright, some areas seem to be warmer than other areas. Astronomers had suggested that this discrepancy may be the result of our Sun warming certain dark patches on Makemake’s surface. However, unless Makemake is in a special orientation, these mysterious dark patches should cause the ice dwarf’s brightness to vary substantially as it rotates. But this amount of variability has not been observed.

Earlier infrared data did not have sufficient resolution to separate MK 2 from Makemake’s veiling glare. The astronomers’ reanalysis, however, based on the more recent HST observations, indicates that much of the warmer surface spotted earlier in infrared light may simply be the dark surface of the companion MK 2.

Several possibilities could provide an answer as to why the moon would have charcoal-black surface patches, even though it is circling a dwarf planet that is as bright as freshly fallen snow. One theory that has been suggested proposes that, unlike larger objects such as Makemake, its own little companion moon is so small that it cannot gravitationally keep a grip onto a bright and icy crust, which then sublimates, undergoing a sea-change from solid to gas under the melting influence of warming sunlight. This would make the little moon akin to comets and other KBOs, many of which are well-coated with very dark material.

When the American astronomer James Christy discovered Pluto’s largest moon Charon back in 1978, astronomers were quick to calculate the mass of the system. Pluto’s mass was hundreds of times smaller than the mass originally estimated for it when it was first discovered in 1930. With Charon’s discovery, astronomers suddenly acquired a new understanding that something was fundamentally different about Pluto.

Dr. Parker noted in the April 26, 2016 Hubble Press Release: “That’s the kind of transformative measurement that having a satellite can enable.”

Judith E. Braffman-Miller is a writer and astronomer, whose articles have been published since 1981 in various magazines, journals, and newspapers. Although she has written on a variety of topics, she particularly loves writing about astronomy, because it gives her the opportunity to communicate to others the many wonders of her field. Her first book, “Wisps, Ashes, and Smoke,” will be published soon.