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Introduction
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It should always be remembered that science is about asking
questions. Albert Einstein: "The important thing is not to stop questioning."
The importance of continuing to ask questions, never
automatically taking anything an authority tells you at face value,
cannot be over-emphasised. Even the most brilliant scientists
sometimes make mistakes, or get their facts wrong. Furthermore,
what is widely accepted as scientific fact by one generation may be
completely discounted by later generations. This is not to say that
the findings of modern science can't be trusted; clearly, thousands
of technical innovations in medicine, electronics, aviation, and
myriad other fields testify to the extraordinary power of the scientific method. When a cherished scientific theory is overturned, it is
typically because a new, more powerful theory, incorporating many
features of the earlier theory, has provided even greater insight
into the workings of nature.
The Star Trek view of the future is an essentially optimistic
view, a future with few limits, few boundaries. The science fiction
writer Jules Verne once said, "What one person can imagine,
another can create." And yet who could have imagined, three hundred years ago, nuclear-powered spacecraft, desktop computers,
solar cells, genetic engineering, and a thousand other miracles of
modern science and technology that are largely taken for granted
today?
The visionary Renaissance artist and inventor Leonardo Da
Vinci (who appears in two stories in [Voyager], namely [#68 Scorpion, Part One] and [#79 Concerning Flight]) imagined a variety of flying machines, including one based on the principles used
to build modern helicopters. Of course, Leonardo's drawings of flying machines bear only marginal similarity to modern aircraft. The
same will certainly be true of Star Trek's vision of starships and
other 24th century technologies. Future starships will no
doubt look very different from USS Voyager, but almost
certainly starships will someday be built. There are no fundamental
laws of physics that preclude the possibility of interstellar travel
(at least at sublight velocities), and we may yet discover some
ingenious means to travel faster than light. It is the hope of everyone involved with the creation of the Star Trek universe that
humanity will rise above the differences that divide us and join
together in the great adventures that await us among the stars.
The Science Primer is an extremely cursory overview of some of the basic definitions and concepts discussed in Bormanis' book 'Star Trek: Science Logs'. about Bormanis and the book It is not by any means intended to be a complete review of basic astronomy, physics, chemistry and biology.
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Units of Measurement |
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The following is a brief review of some of the international system units commonly used in the sciences and throughout this site section.
Mass is measured in kilograms. A kilogram is about 2.2 lbs. Distances are measured in metres. A metre is approximately 31 inches. (In the USA "metre" is spelled "meter", although in Britain the distinction is made spelling-wise between a "meter" as a device for measuring something, such as electricity usage, whereas "metre" is the unit of distance measurement. But aurally, one must rely on listening for context only.) A kilometre is a thousand metres, which is about 0.6 miles. Very small distances are typically measured in microns. A micron is a millionth of a metre. Another unit of small distances, commonly used in optics, is the angstrom, which is a ten-millionth of a metre. The wavelength of visible light ranges from about 4,000 angstroms (blue) to 7,000 angstroms (red).
Angles are measured in a unit called radians, but a more convenient unit for the purposes of this book is degrees. A circle contains 360 degrees. A degree is further divided into 60 minutes of arc, and a minute of arc contains 60 seconds of arc. The ancient Babylonians and ancient Greeks set up the basis of these units.
Since astronomical distances are typically very larger, a special set of units is used in astronomy. The astronomical unit, as it is known, is the mean distance from the Earth to the Sun, about 150 kilometres. A light-year (it can also be spelled without a hyphen) is defined as the distance a beam of light, travelling at 186,000 miles per second, travels in one year. The average distance between stars in the spiral arms of our galaxy is four or five light-years. The next closest star to our solar system, Proxima Centauri, is a little more than four light-years away. Four light-years is roughly equivalent to 24 trillion miles! A parsec is the distance from the Earth that a star or other
astronomical object would have to be to shift its apparent position
(due to parallax) by one second of arc as the Earth moves from one
side of its orbit to the other. A parsec is equal to 3.26 light-years.
Big and small numbers are very common in astronomy and
physics. To make it easier to handle such numbers, mathematicians long ago devised exponential notation. In exponential notation, the exponent is used to indicate how many zeros follow the
number before the exponent. For example, 3 104 ("three times ten
to the fourth power") represents a three followed by four zeros
(30,000), or thirty thousand. Negative exponents are used for very
small numbers: 710-3 represents 0.007, or seven thousandths.
The basic unit of force in physics is the newton, named in honour
of English physicist Sir Isaac Newton (who is brought on board USS Voyager in [Death Wish] for a short time). A newton is the amount of force required to
impart an acceleration of one metre per second to a one-kilogram
mass. Another unit, the dyne, is used for smaller forces; one newton
equals 105 dynes. Energy is often defined as the ability to do work.
The basic unit of energy in physics is the joule, which is the amount
of work done by a force of one newton applied over a distance of one
meter. The basic unit of power is the watt. A watt is simply one joule
of energy expended (or consumed) per second. In atomic physics,
energy is commonly measured in electron volts (ev). One ev is the
kinetic energy (energy of motion) imparted to an electron when it is
accelerated through a potential difference of one volt. Since Einstein
demonstrated that matter and energy are equivalent, the masses of
subatomic particles are frequently given in electron volts.
In the United States, newspapers and television news shows
typically report local temperature in degrees Fahrenheit. In Britain (and ?all of? Europe), the system changed years ago and temperature are given in Celsius, although many people still often think in terms of Fahrenheit; for instance, an easy conversion mnemonic is 16° Celsius (a comfortable temperature for people) = 61 ° Fahrenheit (the numbers appear physically reversed). In the
metric system, temperatures are measured in degrees celsius (C)
or kelvins (K). Water freezes at zero degrees C, and boils at 100°C. Absolute zero, the temperature at which all
motion would theoretically cease,* is -273 C, and is also defined
as zero degrees kelvin, or zero kelvins. A change in temperature of
one degree C is equivalent to a change in temperature of one
kelvin, hence, the freezing point of water is 273 kelvins.
* In practice, this can never happen, due to quantum mechanical effects.
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Celestial Cataloguing |
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There are numerous catalogues (too numerous to list here) listing celestial objects. Catalogues have varying amounts of content, and vary as regards recognition by the community of astronomers and extent of usage. Often the brightness of objects is employed to define the catalogue's parameters. The following examples are not given in any order after the entries NGC and Messier:
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When one sees the letters NGC in front of the designation for a stellar feature, the acronymic prefix stands for the New General Catalogue (NGC), which was originally compiled and published by J.L.E. Dreyer in 1888. Two additional supplements, the Index Catalogue (IC), were published in 1895 (IC I) and 1908 (IC II). These catalogues were an early attempt to place all the non-stellar objects known at the time in one list and does contain a few mistakes due to optical error or incorrect logging of co-ordinates, and there are of course celestial objects which do not fit into any of the NGC-IC catalogue's categories of deep space objects; many of these objects may be supernova remnants. The original NGC-IC catalogue contains 13,226 entries. There have been several attempts since then to update the catalogue, including one by Wolfgang Steinicke, whose catalogue lists 13,993 objects.
 | left: The North American Nebula, so named for its shape which approximates to the North American continent with a replica of the Gulf of Mexico, is a huge emission nebula. This nebula, designation NGC 7000, glows with the red light of heated hydrogen gas. |
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When one sees the letter M in front of a number, so that the two together designate a celestial feature, the M stands for Messier. Astronomer Charles Messier observed the Crab Nebula in 1758 while searching for Halley's Comet. This was the inspiration for Messier to compile a catalogue of all "fuzzy" celestial objects in the night sky so as not to confuse them with the short-lived comets he was trying to discover. The resulting catalogue of 110 objects is known as the Messier Catalogue, and some of the most popular celestrial bodies among amateur astronomers are the Messier objects. The Crab Nebula is the only supernova remnant in the Messier catalog, and has the designation M1.
 | left: The Crab Nebula, which is the remnant of a star that exploded as a supernova in 1054. The supernova was visible in the daytime for 23 days, shining four times brighter than Venus and visible to the naked eye in the night sky for almost two years before fading out. What one sees today is the gaseous material ejected by the exploding star. This material is moving outward from the nebula's center at 1800 km/s. At the nebula's core is an extremely dense neutron star or pulsar, which rotates 30 times per second. |
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The catalogue of Principal Galaxies (PGC) was compiled from data in the Lyon-Meudon Extragalactic database and it was published in 1992 (G. Paturel, L. Bottinelli, P. Fouque and L. Gougenheim). It is a catalogue containing primary information for 73,098 galaxies. |
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There is also a database of Bright NGC Objects which includes 69 deep space objects, including many which are favourites of amateur astronomers, such as the Veil Nebula (NGC 6960; it is the remnant of a supernova explosion which occurred thousands of years ago), the Eta Carinae Nebula (NGC 3372; it contains the distinctive Keyhole Nebula), and the Omega Centauri Cluster (NGC 5139, a blazing ball containing over one million stars; they did not all form at the same time). What one sees of course depends which hemisphere one is in. The database is a mixture of star clusters, nebulae and galaxies. |
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There is a database cataloguing Bright Objects includes 179 deep space objects, again including many that are favourites of amateur astronomers, such as the Andromeda Galaxy, the famous Orion Nebula and the Great Hercules Cluster. The database is a mixture of star clusters, nebulae, and galaxies; all 110 Messier objects are in this database, plus some of the best-known NGC-IC objects. |
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The Saguaro Astronomical Catalogue contains over 11,000 double and multiple star systems. (Some apparent multiple star systems are actually "optical doubles" i.e. stars that appear very close together but are physically separated by a large distance in space. Only our angle of sight makes these two stars appear as one. True multiple stars are gravitationally bound, revolving around a common centre of mass.) Astronomers believe that more than half of the stars in our galaxy belong to a multiple star system. |
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The Herschel 400 is a subset of 18th century astronomer William Herschel’s catalog of deep space objects. It is designed as a list of objects for amateur astronomers to observe after they have seen all the Messier objects - all objects in the catalogue should be visible in a medium-size telescope under dark skies. The Herschel 400 was originally compiled by Brenda Branchett. |
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Groups or societies of astronomers (professional, amateur or a mix) might compile their own catalogues. Examples: the Uppsala General Catalogue of 13,000 galaxies; the catalogue produced by the American Association of Variable Star Observers of variable stars (stars that change in brightness - most variable stars are either 'pulsating variables' or 'eclipsing binaries') plus the General Catalogue of Variable Stars based on data from Kopolev et. al (1988) and NASA/ADC (1997); the Royal Astronomical Society Observer's Handbook; people participating in the internet newsgroup sci.astro.amateur once voted to select the top 100 non-Messier deep space objects; and the Nautical Almanac details the 57 bright stars used for celestial navigation. |
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The Hubble Space Telescope |
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In the years since it was launched on Space Shuttle Discovery in August 1990, the Hubble Space Telescope (HST) has advanced the science of astronomy, and produced many stunning and colourful images. Some of HST's most important scientific results include the discovery of supermassive black holes at the centre of galaxies, providing proof that quasars are the active galactic nuclei of distant galaxies, and evidence that the expansion of the universe is accelerating.
artist's depiction of the Hubble Space Telescope, from my screensaver program
The HST is a 2.4 metre reflecting telescope. Its position above the interfering effects of the Earth's atmosphere allows the telescope to have 0.1 arc-second resolution, 4 times better than the best ground-based telescopes using adaptive optics. Several space shuttle missions have serviced the Hubble Telescope and expanded its capabilities, beginning with a repair mission in December 1993 which fixed optical problems in the Telescope's main mirror. The HST is scheduled to operate until the year 2010, when it may be lowered back to Earth, launched into a higher orbit, or burned up in Earth’s atmosphere. NASA's current plan is to decommission its space shuttle fleet by the same year. Orbiting 600 km above Earth, the HST circles the planet every 100 minutes. It can often be seen with the naked eye near sunset or sunrise, as bright as first or second magnitude.
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The Milky Way Galaxy |
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Galaxies are vast stellar cities, containing anything from several million to several trillion stars. However, most of the mass in galaxies is not in stars but in a mysterious form of 'dark matter' which scientists have not yet identified. At the centre of many galaxies lies an object millions of times more massive than the Sun. These supermassive objects may be black holes. 4/5ths of the known galaxies are spiral galaxies, while 1/5th are ellipticals. 3% of galaxies do not fit either of these classifications, and are called ‘irregular’ galaxies. Elliptical galaxies are football-shaped; they have very little gas and dust, and no new star formation is occurring within them, and they have a wide range of sizes - both the largest and smallest known galaxies in our universe are elliptical galaxies. Spiral galaxies consist of a bright central bulge surrounded by a thin disk made up of spiral arms. Some spiral galaxies have a bar running through the nucleus. The arms of a spiral galaxy are sites of star formation, and are filled with gas and dust. The older central region does not exhibit star formation. Our Milky Way is a spiral galaxy, slightly larger than average, with several hundred billion stars. Irregular galaxies do not have a structural pattern. They may be former spiral or elliptical galaxies which were disrupted by close encounters with other galaxies.
| right: M100 galaxy photographyed by the Hubble Space Telescope. M100 is a face-on spiral galaxy, and one of the larger members of the Virgo Cluster. The Hubble Space Telescope recently measured the distance to M100 using Cepheid variable stars, and used this distance measurement as one of the pieces of data in a new measurement of the age of the universe. The results of this study indicate that the universe is about 14 billion years old. |  |
Both the Large and Small Magellanic Clouds are irregular galaxies; the Large Magellanic Cloud (LMC) is one of the closest galaxies to our own Milky Way, being only 180,000 light years away, and closer than its companion galaxy, the Small Magellanic Cloud. Galaxies are the most distant objects we can observe in the night sky and a handful of galaxies can be detected with the naked eye or binoculars preferably a telescope. For most spirals, the bright nucleus can be seen, surrounded by a faint envelope, but it is often difficult to distinguish spiral arms. As seen from Earth, a large fraction of the nearest few thousand galaxies are concentrated in a narrow band, and the centre of this band is defined as "the extra-galactic equator".
In the Star Trek universe, the United Federation of Planets was
chartered to facilitate the peaceful exploration of the Milky Way
Galaxy, a pinwheel structure of four hundred billion stars stretching 100,000 light-years end-to-end. The Earth orbits
an average main sequence star located in one of the spiral arms,
about 30,000 light-years from the galaxy's centre. The Sun
and its planets comprise our solar system (or planetary system;
the terms are interchangeable). When the Voyager crew refer to the galaxy, they mean the Milky Way galaxy.
On Star Trek the galaxy is divided into into four equal-sized quadrants (note that this is not common practice in real astronomy). Each quadrant contains approximately one hundred billion stars. Earth and the majority of Federation planets are located in the Alpha Quadrant. The [DS9] wormhole leads from the Alpha Quadrant to the
Gamma Quadrant. The Barzan wormhole, featured in [False Profits], brought the two Ferengi named Arridor and Kol from the Alpha Quadrant to the Delta Quadrant.
the Milky Way galaxy of the 24th century Star Trek universe, divided into four quadrants, source STSC
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Stars |
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Stars in the Milky Way Galaxy feature a wide variety of masses, diameters, surface temperatures, and luminosities. Every star is essentially a spherical mass of very hot gas, primarily hydrogen, producing
energy through the process of nuclear fusion. Deep in the cores of
most active stars, gas pressures reach thousands of times the atmospheric pressure at the surface of the Earth. Temperatures rise to millions of kelvins or more. The intense pressure and heat in a star's core
forces some of the hydrogen atoms there to fuse into helium atoms.
This process releases energy in the form of X rays. The X rays generated in a star's core radiate outward toward the star's surface, losing
energy along the way as they riccochet among the innumerable atoms
comprising the star's bulk. Eventually this radiated energy emerges
from the surface of the star, primarily in the form of visible light.
The star most familiar to humankind is the Sun. The Sun is a
more or less average star in terms of mass and luminosity. It is classified as a G-type star.
our sun
Following a convention established in the
nineteenth century, stars are classified by letters that roughly correspond to their surface temperatures. The letter sequence of stellar classification, in descending order of temperature, is O B A F G K M N.
O-type stars are the hottest stars, with surface temperatures
sometimes exceeding forty thousand kelvins. G stars, like the Sun,
have surface temperatures on the order of six thousand kelvins. N
stars, the coolest stars, are a relatively "chilly" three thousand
kelvins. The letter assignations can be remembered by the phrase,
Oh Be A Fine Girl [or Guy], Kiss Me Now.
Stars come in many sizes, from dwarfs to giants. The Sun is an
average-size star, perhaps even a bit on the small side at roughly
1.4 million kilometers in diameter. One of the largest stars in our
neighborhood, Betelgeuse, a red giant, averages several hundred
million kilometers in diameter. Placed at the Sun's location,
Betelgeuse would extend beyond all of the planets in the inner
solar system, including Earth. The diameter of this red giant is not
constant, but changes as the star pulsates; Betelgeuse is an example of a variable star. The brightness of Betelgeuse varies in rhythm with its pulsating atmosphere.
Single stars are in the minority in our galaxy. Most stars are gravitationally bound to a stellar partner. Binary stars are two stars that
orbit around the same point in space, called the barycenter of the
binary system. For two stars of identical mass, the barycenter is located exactly between them. In most binaries, the two stars have different masses; in these cases, the barycenter is proportionally closer to
the more massive member of the pair. Trinary stars - systems consisting of three stars orbiting a common point in space - are also fairly common, the closest example being our nearest stellar neighbours
Alpha Centauri A and B and their diminutive companion Proxima
Centauri.
Pulsars are neutron stars, former supergiants that have been compressed into spheres with diameters of only a few tens of kilometres. These neutron stars spin very rapidly and emit radiation from their poles. As the neutron star spins, the amount of radiation that reaches us varies significantly, and the star appears to pulse in brightness, hence the name 'pulsar'. Janeway takes Voyager toward a binary pulsar in [Scientific Method].
 The ancient Greeks identified patterns among the stars and
gave them names. These are the constellations, predominantly
named after the characters of Greek mythology. From their
Mediterranean home, the Greeks could not see most of the stars of
the southern hemisphere. Post-Renaissance explorers observed the
southern skies and designated constellations there. Many of these
constellations were named after the inventions that made the exploration of the Earth's oceans possible, such as Sextans (the sextant), Vela (the sails), and so on. Other cultures, such as the Navajo of Arizona and the
Mayans of Central America, created their own constellations. Today
there are eighty-eight constellations recognised by the International Astronomical Union (IAU). At about the end of the 19th century, the IAU drew format boundaries around the eighty-eight constellations, and these borders are still used today.
The ancient Greeks rarely bothered to name individual stars;
they were mostly interested in star groups. The ancient Persians,
on the other hand, were mostly interested in observing individual
stars: The stars' rising and setting times were used as a kind of
celestial calendar. Most of the star names we use today are therefore Arabic in origin: Antares, Rigel, Zuben el Genubi, and so on.
A star can also be named by its brightness (as seen from Earth)
within its home constellation. The letters of the Greek alphabet are
used to designate relative brightness. The brightest star in the constellation Orion, for example, is Alpha Orionis, which is also known as Betelgeuse. The second brightest star in that constellation is
Beta Orionis, etc. Note that the genitive form of the constellation name is used in this naming scheme.
Excerpt from [#159 Repentance]
Iko: "When I was a child I'd lie under the stars for hours. I'd stare at them until I could see the shapes."
Seven: "Shapes?"
Iko: "Faces and animals made out of stars."
Seven: "You're referring to constellations?"
[#159 Repentance] |
In the astrometrics lab, Iko shows Seven a constellation comprising a star, "Ornella the Mother" surrounded by sixteen other stars, her Daughters: "She's beautiful, isn't she?"
Seven: "Ornella the Mother."
Iko: "And there's Pados, still watching over her." |
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Planets and Planetary Systems |
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click to enlarge, 1024x232 pixels composite picture of our solar system employing a mix of concepts by various artists and pictures taken by the Hubble Space Telescope, showing left to right: sun, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto; there is debate as to whether Pluto is a planet; shortly after compiling this article the IAU decided to downgrade Pluto causing dismay amongst many professional and amateur astronomers
Planets are spherical cosmic bodies substantially smaller than stars,
composed of varying combinations of metals, minerals, liquids, ices,
and gases. Unlike stars, planets do not generate light and energy
through nuclear fusion. Planets appear as points of light in the sky
because they reflect sunlight. The two major classes of planets are
the terrestrial planets, which feature solid surfaces and relatively
thin atmospheres or no atmosphere at all; and jovian planets, large,
mostly gaseous bodies that may or may not include solid cores. Jovian planets: Jupiter, Saturn, Uranus and Neptune
Jupiter, a jovian planet ("jovian" actually derives from Jove, another
name given by the ancient Romans to their god Jupiter)
Jupiter Station in orbit of Jupiter, [#144 Life Line]
In the Star Trek nomenclature, terrestrial planets with breathable atmospheres are called Class-M planets, part of the planetary classification system employed by the Federation Starfleet. Gas giants like Jupiter are known as Class-J planets. J stands for jovian.
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The Fullness of Space |
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Contrary to popular belief, space is not empty. The mixture of
rarefied gases, dust particles, and electromagnetic fields that permeate most of the galaxy is called the interstellar medium (ISM).
Voyager emerges from the Void, [#95 Night] |
Kim: "I see a densely packed region with thousands of star systems. Looks pretty lively." |
The average density of the interstellar medium is extremely low:
roughly one atom of hydrogen per cubic meter. By comparison, a
cubic centimeter of air on Earth at sea level contains some fifty billion billion atoms. Hydrogen atoms are the most common constituent in the ISM. (Hydrogen is, in fact, the most common element in the universe.) Heavier elements, as well as molecules,
including some simple organic molecules, are also found in the ISM.
Grains of interstellar dust are found throughout the ISM. They
are typically comprised of a core of silicate or graphite (carbon)
material, surrounded by a mantle of lighter molecules (often ices of
methane, carbon dioxide, ammonia, and water). The surfaces of
interstellar dust grains can act as catalysts for relatively complex
chemical reactions, producing organic molecules that form a coating on the grain. Dust grains, attracted by their mutual gravity, often accumulate in molecular clouds, which can span many light-years.
A large interstellar cloud of gas and dust is called a nebula. In
addition to being extraordinarily beautiful, nebulae are the birth-places of stars. Drawn together by gravity, clumps of gas and dust
collapse within a nebula, growing hotter through friction, drawing in
more nebular matter as the knot of gas grows. Eventually a pocket
of gas becomes hot and dense enough to cause the hydrogen
atoms at its center to collide and fuse into helium atoms. Through
this process a star is born.
USS Voyager enters a nebula, [#145 The Haunting Of Deck Twelve]
There are three major types of nebulae:
- Emission nebulae are regions of hydrogen gas very close to young, hot stars. Light from the stars heats the hydrogen gas, raising its temperature up to 10,000 K. At this temperature, the gas cloud glows red, giving emission nebulae their distinct reddish appearance. (Klingon-style cloaking devices will not operate within emission nebulae, as indicated in [DS9: Return to Grace].)
- Reflection nebulae are regions with a higher density of dust. This dust scatters the light from nearby stars. Blue light is scattered more effectively than red light, so reflection nebulae appear blue. Many nebulae have both emission and reflection components. Such nebulae are often regions where new stars are being formed.
- Dark nebulae have a higher concentration of dust, which blocks almost all light from background stars, making this region of sky dark and featureless.
the most famous nebula is the Orion Nebula, which is a combination emission and reflection nebula
How long a star will live is largely a function of the star's mass.
Very massive stars exhaust their supplies of hydrogen much more
quickly than lower-mass stars. The amount of time a star spends on
the main sequence of stellar evolution can range from a few million to
ten or more billion years. (The USA "billion" is not as big as the European "billion".) Our Sun, a fairly average star, has been converting hydrogen into helium more or less steadily for some five billion
years, and will probably continue to do so for another five billion years.
A planetary nebula is the term given to the last stage of life of a dying star. In its last act before becoming a white dwarf, a red giant star ejects a shell of hot hydrogen gas. This shell is visible to us as a planetary nebula. Planetary nebulae have short lifetimes. As the gas shell moves outwards from the central star, the nebula grows larger and fainter. After about 10,000 years, the gas shell is too faint to be seen, having blended in with the surrounding interstellar medium. Planetary nebula are so named because many appear blue-green and look similar to the planet Uranus through a small telescope. Planetary nebulae are among the only deep space objects for which colour can be seen through the telescope. Planetary nebulae only emit light at certain frequencies (one can buy special nebular filters to attach to one's telescope but they are expensive) Some of the most famous planetary nebulae are the Dumbbell Nebula (NGC 6853), the Ring Nebula (NGC 6720), and the Eskimo Nebula (NGC 2392).
| right: The Dumbbell Nebula, M27, taken by the Hubble Space Telescope. This nebula is the brightest planetary nebula in the night sky, and was the first planetary to be discovered. It contains multiple gas shells moving away from the central star at different speeds. An oxygen shell is moving outwards at 15 km/s, while a faster nitrogen shell is expanding at the rate of 30 km/s. |  |
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Atoms and Subatomic Particles |
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The early 19th century chemist John Datton established the
modern atomic theory of matter, which asserts that all the different forms of matter we find in the world are composed of various
combinations of a small number of chemical elements, or atoms.
The Periodic Table of the elements, which everyone has to learn by heart at school (and maybe forgets later), charts the basic properties of the atoms that make up ordinary matter.
An atom itself is made up of subatomic particles. The particles
in an atom are organised into a nucleus, composed of protons and neutrons, surrounded by a cloud of electrons in orbit around the
nucleus. Many subatomic particles carry an electrical charge.
Protons have a positive electrical charge, electrons have a negative
charge, and neutrons have no charge. The force of attraction
between positive and negative charges keeps electrons in orbit
around the nucleus.
Some particles are made up of even smaller particles. Protons
and neutrons, for example, are composed of particles called quarks
(not to be confused with the Ferengi bartender at Deep Space 9). Electrons,
on the other hand, are fundamental particles; they cannot be further broken down (so far as we know) into smaller constituents.
Quarks are also fundamental particles.
Since the English physicist Ernest Rutherford discovered the
electron in 1910, hundreds of other subatomic particles have been
discovered. Most of them are unstable, short-lived particles, byproducts of nuclear reactions or other energetic processes. Some subatomic particles are listed in the table below.
A Few Subatomic Particles
Name Mass* Charge
Proton (consists of three quarks) 1 +1
Neutron (consists of three quarks) 1 0
Electron (fundamental particle) 1/1836 -1
Neutrino † <10-8 0
Quarks:
UP 1/235 +2/3
Down 1/135 -1/3
Strange 1/6 -1/3
Charm 1.6 +2/3
Bottom 5.2 -113
Top 170 +2/3
A proton consists of two up quarks and a down quark; a neutron
consists of two down quarks and an up quark. Particles called gluons bind quarks together within protons and neutrons. Quarks and electrons are fundamental particles, i.e., they are not composed of still smaller particles (so far as we know).
* In terms of proton mass; the neutron is actually slightly more massive than the proton.
† It is not clear whether the neutrino has mass, but if it does, its mass is very small.
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All of the subatomic particles discovered to date have corresponding antiparticles. The antiparticle corresponding to the electron,
for example, is the positron. It has the same mass as an electron, but
an opposite electric charge. Antimatter is the term given to the
family of antiparticles; in the Star Trek universe, various forms of
antimatter play an important role in starship propulsion and power
generation.
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Molecular Biology |
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Living tissues are primarily made up of very complex organic molecules. The carbon atom is the defining constituent of an organic
molecule. Any molecule that contains carbon (with the exception
of a few simple compounds such as carbon monoxide and carbon
dioxide) is considered an organic molecule.
A chemical formula is a shorthand way of writing down the
name of a chemical compound or molecule. Carbon monoxide consists of one atom of carbon and one atom of oxygen. Its chemical formula is CO. Carbon dioxide consists of one atom of carbon and two atoms of oxygen. Its chemical formula is CO2.
Atoms in molecules are held together by atomic bonds, which
arise from forces due to the interaction of the atom's electrons.
There are a number of different kinds of atomic bonds, but the
most common are ionic and covalent. In an ionic bond, one atom
gives up an electron to another atom. The atoms are bonded
together by their electrical attraction: the atom that lost an electron
has a net positive charge, and the atom that gained an electron has a net negative charge. In a covalent bond, electrons are shared between atoms.
DNA, or deoxyribonucleic acid, is an extremely complex organic molecule, and in fact is the "master molecule" of all life on Earth. DNA molecules are made up of two intertwined chains of simpler
molecules called bases, assembled on rails of sugar and phosphate molecules like rungs on a ladder. The characteristic double-helix shape of the DNA molecule was discovered by
Watson and Crick in 1955. Four different kinds of molecules form
the rungs of the DNA ladder: adenine, thymine, guanine, and cytosine, which are typically referred to by their first letters, A, T, G, and
C. In the DNA molecule, A always pairs with T, and G always pairs
with C.
DNA molecules replicate by "unravelling" their rails. Each rail
keeps its associated base. Complementary bases (A for T, G for C)
attach to the free bases until two new strands of DNA are created.
Icheb examines data on his DNA
[#148 Imperfection] |
Icheb watches Naomi Wildman assembling a jigsaw of a humanoid DNA molecule. Icheb: "Excellent. You recognised the complementary base pair." Naomi: "Actually, I just found two pieces that fit together."
[#157 Shattered] |
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Fields and Electromagnetic Radiation |
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Every subatomic particle is the source of at least one field. A field
is essentially a mathematical representation of the "sphere of
influence" of a charged particle. Particles interact through their
fields. A proton at rest, for example, exerts a force on an electron
through the action of an electric field. Moving electric charges gen-
erate magnetic fields.
The 19th century English physicist Michael Faraday recognised that a fundamental relationship exists between electricity
and magnetism. Another nineteenth-century physicist, James Clerk
Maxwell, a Scotsman, determined that ripples in electric and magnetic fields, propagating through space, create electromagnetic
(EM) radiation. Maxwell discovered that electromagnetic radiation
travels through space at the speed of light, and he concluded that
light is a form of electromagnetic radiation. We now know that radio
waves, infrared radiation, visible and ultraviolet light, X rays, and
gamma rays are all forms of electromagnetic radiation.
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The Electromagnetic Spectrum and Basic Sensor Technology |
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Visible light is the most familiar form of EM radiation. The colours of
the rainbow, however, comprise only one small segment of the electromagnetic spectrum. To make an analogy with sound, if the EM
spectrum were the keyboard of a piano, humans would be able to
hear only a few notes near middle C (it should be noted that sound
waves are not EM waves; sound waves are periodic vibrations in the
air or some other physical medium, and therefore cannot travel
through the vacuum of space).
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Waves and Photons |
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Electromagnetic waves are characterised by two numbers: wave-length and frequency. The wavelength of an EM wave is the dis-
tance between adjacent wave crests or troughs. This distance can
be measured in meters or angstroms (10-10 meters). Frequency is
the number of waves that pass a given point in a given time. The
unit of frequency is the hertz, or reciprocal seconds. One hertz corresponds to the passage of one wave per second.
 The wavelength of light perceived by human eyes as "red" is about seven thousand angstroms. Deep blue or violet light corresponds to roughly four thousand angstroms. The rest of the familiar "colours of the rainbow" fall somewhere in between. In order of decreasing wavelength, the colours of the rainbow are Red, Orange, Yellow, Green, Blue, Indigo, Violet - which can be easily remembered through the acronym ROY G. BIV. There is also the acronymic mnemonic: Richard of York Gave Battle In Vain.
Radio waves have the longest wavelength of all EM waves,
sometimes stretching many kilometres, but more commonly on the
order of a few metres. Their frequencies range from a few hertz to
thousands and millions of hertz. Next comes infrared radiation,
ranging in wavelength from around one micron (a millionth of a
metre) to seven thousand angstroms. As mentioned above, visible
light extends from about seven thousand to four thousand
angstroms. Ultraviolet light ranges from four thousand angstroms
to about ten angstroms. X rays have shorter wavelengths (and thus
higher energies) stitt: about ten angstroms to .1 angstrom. Finally,
any EM wave whose wavelength is less than .1 angstrom falls in the
gamma-ray portion of the spectrum.
Maxwell discovered that the product of any electromagnetic
wave's wavelength (represented by the Greek letter lambda) and
frequency (represented by the Greek letter v, nu) is always equal to
the speed of light, i.e., lambda v = c. Knowing the wavelength of an EM
wave, one can easily determine its frequency, and vice versa. It was
also discovered around this time that the energy of an EM wave is a
function of its frequency: the higher the frequency of an EM wave,
the greater will be its energy. The German physicist Max Planck recognised around the beginning of the twentieth century that the energy
of an EM wave is equal to its frequency times a constant of proportionality (now called Planck's constant) whose value he determined.
The energy of a photon in joules, E, equals h v, where h, Planck's
constant, is 6.63 10-34 joule-sec, and v is the frequency of the photon measured in hertz.
This implies that low-temperature (room temperature and
below) objects mostly emit long-wavelength, i.e., low-energy radiation, such as radio waves and infrared. Very hot objects (temperatures measured in tens of thousands of kelvins) on the other
hand, mostly emit short-wavelength, i.e., high-energy radiation,
such as ultraviolet and X rays.
The quantum theory of matter treats EM radiation not as
waves but as discrete particles of energy called photons. A photon
is, in effect, a particle of light. The energy of a photon is proportional to its frequency: the higher the frequency, the higher the
energy of the photon. Infrared photons have relatively low energy.
X-ray and gamma-ray photons have the highest energy.
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Sensor Technology |
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A variety of instruments have been developed to detect and measure radiation throughout the EM spectrum, from the longest
wavelength radio waves to the shortest wavelength gamma rays.
Large, dish-shaped radio antennas are used to measure radio
waves from space. The largest radio telescope in the world is located near Arecibo, Puerto Rico. The receiving dish of the telescope is
actually built into a shallow crater some three hundred meters in
diameter. The radio-wave detector, suspended high above the
dish, moves and changes orientation to point the telescope at different objects.
Near-infrared through ultraviolet radiation can be gathered
and focused by conventional reflecting telescopes. The largest
optical telescopes in the world are currently the twin ten-meter
Keck telescopes in Mauna Kea, Hawaii.
Solid-state detectors have largely replaced photographic film
for taking pictures of distant objects in space. Some of the astronomical photos in this book were taken by so[id-state detectors, which are also known as CCD cameras. The heart of a CCD camera is a specially treated silicon chip (much like a computer chip) which is extremely sensitive to light. The chip is divided into a grid of pixels, or picture elements, each some ten to twenty microns square.
To take an image of an astronomical object, the CCD camera is
placed at the focus of a telescope. Light striking the CCD chip generates an electric current in each of the pixets proportional to the
intensity of the light. A computer reads out the current in each
pixel, and displays the corresponding intensity of the light intercepted by each pixel. Similar to a newsprint photo or a
pointillist painting, the image really consists of tiny separate bits of colour: in this case, an array of tiny squares of varying shades of
gray. Using a series of colour filters, CCD cameras can be used to make full colour as well as black-and-white images.
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Faster-Than-Light (FTL) Propulsion |
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In the Star Trek universe, a brilliant but eccentric (aren't they
always?) scientist named Zefram Cochrane developed the first
practical FTL propulsion system, the celebrated warp drive, in
2o63. Space warps have been a subject of serious scientific
research since Albert Einstein created the general theory of relativity in 1915. Einstein showed that matter warps space; in other
words, space itself is not "flat" but curved. Just as we cannot
directly perceive the curvature of the Earth while standing on its
surface, we cannot directly perceive the curvature of space, but it is
just as real.
In his special theory of relativity, Einstein demonstrated that
nothing can travel faster than the speed of light in a vacuum. As
noted above, the nearest star beyond our solar system, Proxima
Centauri, is a bit more than four light-years away. Since nothing
can travel faster than light, a journey to Proxima Centauri would
require at least four years.*
*As measured by an observer on Earth-the relativistic effect known as time dilation
would lead to a different reckoningoftraveltimeamongthe crewofa starship travelingat
near-light speed.
The idea of using "warped" space as a kind of loophole to circumvent the laws of special relativity has been examined by many scientists, but no one has yet developed a practical means of creating a
space warp for propulsion. According to the general theory of relativity, the presence of matter is the only thing that warps space. High
concentrations of extremely dense matter - in a black hole, for example - will warp space to an extreme degree (high concentrations of energy can also warp space, since, according to relativity theory, matter and energy are different manifestations of the same thing). Black
holes may also be connected to other points in space through worm-
holes, cosmic short cuts through the curved space-time fabric of our
universe. The question of how to create and manage space warps
through the application of forces we know how to control - such as
the electromagnetic or nuclear force - will have to await a fundamental breakthrough in basic physics.
For much of the twentieth century, theoretical physicists have
struggled to achieve what many would consider the ultimate theory: a
"theory of everything." Such a theory would be a single mathematical
formulation that unifies all four fundamental forces in nature: gravitation, electromagnetism, and the strong and weak nuclear forces. The
last three forces were combined into a single unified theory in the
198os, but gravity has yet to be incorporated into the scheme.
Understanding how gravity is one manifestation of a single, general
force may provide the theoretical understanding that will eventually
lead to the ability to manipulate gravitational fields through some
mechanism involving the other basic forces. Or we may discover that
matter is the only thing that can warp space; if this proves to be the
case, "warp drive" may never be a practical means of propulsion.
above screenshots: Voyager jumps to warp speed, stock footage - the warp nacelles are raised, warp engines are engaged and Voyager goes to warp speed with a flash
On Star Trek, we assert that in a starship warp engine, high-energy plasma, created by a matter-antimatter reaction, is pumped
through a series of warp coils cast from an artificial (and fictional)
material called verterium cortenide. Verterium cortenide provides
a bridge between electromagnetic and gravitational forces. By
design, it has the property that when a high-energy plasma circulates through appropriately fashioned verterium cortenide castings, a "warp field" is generated. Electromagnetic interactions
between waves of superhot plasma and the verterium cortenide
coils change the geometry of space surrounding the engine nacelles.
In the process, a multilayered wave of warped space is born, and the
starship cruises off to its next destination at hundreds of times the
speed of light (relative to "normal" space; within the warp field, the starship does not exceed the local speed of light, and therefore does
not violate the principal tenet of special relativity). A more detailed
description of the warp drive and other star Trek technologies can be
found in Rick Sternbach and Mike Okuda's 'Star Trek: The Next
Generation Technical Manual', also published by Pocket Books (this source's standard abbreviation on this site to ST TNG Tech); Rick and Mike developed the scenario described above for the operation
of the warp drive.
In 2372, in [#36 Investigations], after Crewman Michael Jonas sabotages USS Voyager according to instructions from Seska, Voyager requires a supply of verterium cortenide, which is a composite material composed of polysilicate verterium and monocrystal cortenum. The engineering staff need this material to rebuild the warp coils. Neelix says that they may be able to find it on an M-class planet in the Hemikek system that is rich in minerals, thereby unwittingly going to fall into Seska's trap as there are Kazon ships waiting for them there.
An explosion injures Jonas after he secretly sabotages Voyager's engines; his getting injured would deflect any suspicion from him. [#36 Investigations]
SHIP USS VOYAGER: Warp Factors includes chart of warp factor speeds
It is inadvisable to go to warp inside a solar system because exceeding the speed of light near a gravity well can be dangerous if the gravitational potentials are not precisely taken into account, as indicated in [Star Trek I: The Motion Picture] and [DS9: By Inferno's Light].
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Wormholes |
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What we call three-dimensional space is really a curved surface in a
higher dimension. Extensive mathematical analysis of the general
theory of relativity has led physicists to speculate on the existence of
a variety of strange structures in space-time, including wormholes.
Analogous to the tunnel a hungry worm bores through an apple,
wormholes are tunnels in the fabric of space that connect widely separated locations through higher-dimension shortcuts. Wormholes, if
they exist, are thought to be transient phenomena; the slightest grav-
itational flux will trigger the immediate collapse of naturally occurring
wormholes.
telemetry from a microprobe sent through a microwormhole which Kim discovers in the Delta Quadrant
[#7 Eye Of The Needle]
The most famous wormhole in the Star Trek universe is of
course the extraordinary transgalactic wormhole discovered by
Captain Benjamin Sisko in the Bajoran sector of the Alpha
Quadrant. The Bajoran wormhole can take a starship a distance of
fifty thousand light-years in roughly thirty seconds. The stability of
the Bajoran wormhole is maintained artificially through a "scaffolding" constructed of verteron particles. The creators of [DS9] have also devised a race of aliens who live within the wormhole, outside the boundaries of normal space and time.
view of the wormhole from the runabout cockpit, upon the discovery of the first known stable wormhole
[DS9: Emissary]
Verterons are mentioned in [DS9: In the Hands of the Prophets] and [DS9: Playing God]. Verterons can block sensor operation [TNG: The Pegasus]. Verterons are detected from the micro-wormhole encountered by USS Voyager on stardate 48579 in 2371, in [#7 Eye Of The Needle] - see screenshot above for telemetry from that micro-wormhole.
| In 2373, in [#47 False Profits], when Kim and Torres try to bring the Delta Quadrant terminus of the Barzan wormhole to Voyager (rather than have Voyager go look for it), they cause the wormhole to reappear by bombarding the subspace instability with verteron particles. |
Voyager at the Barzan wormhole's Delta Quadrant opening, [#47 False Profits] |
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