Astronomy

Is there a name for a planet and its moons/satellites?

Is there a name for a planet and its moons/satellites?


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I'm wondering if there's a name that encapsulates the concept of a planet and the objects that orbit in its gravity. There's a solar system that encapsulates a star and its multiple planets and other objects, but I don't think that "solar system" describes the Earth and its moon, or Jupiter and it's many moons, for example.


This question has been asked before on the Space Exploration page.

In summary, the term used is system, e.g. the 'Jupiter system'.


G | Selected Moons of the Planets

Note: As this book goes to press, nearly two hundred moons are now known in the solar system and more are being discovered on a regular basis. Of the major planets, only Mercury and Venus do not have moons. In addition to moons of the planets, there are many moons of asteroids. In this appendix, we list only the largest and most interesting objects that orbit each planet (including dwarf planets). The number given for each planet is discoveries through 2015. For further information see https://solarsystem.nasa.gov/planets/solarsystem/moons and https://en.wikipedia.org/wiki/List_of_natural_satellites.

Planet (moons) Satellite Name Discovery Semimajor Axis (km × 1000) Period (d) Diameter (km) Mass (10 20 kg) Density (g/cm 3 )
Earth (1) Moon 384 27.32 3476 735 3.3
Mars (2) Phobos Hall (1877) 9.4 0.32 23 1 × 10 −4 2.0
Deimos Hall (1877) 23.5 1.26 13 2 × 10 −5 1.7
Jupiter (79) Amalthea Barnard (1892) 181 0.50 200
Thebe Voyager (1979) 222 0.67 90
Io Galileo (1610) 422 1.77 3630 894 3.6
Europa Galileo (1610) 671 3.55 3138 480 3.0
Ganymede Galileo (1610) 1070 7.16 5262 1482 1.9
Callisto Galileo (1610) 1883 16.69 4800 1077 1.9
Himalia Perrine (1904) 11,460 251 170
Saturn (82) Pan Voyager (1985) 133.6 0.58 20 3 × 10 −5
Atlas Voyager (1980) 137.7 0.60 40
Prometheus Voyager (1980) 139.4 0.61 80
Pandora Voyager (1980) 141.7 0.63 100
Janus Dollfus (1966) 151.4 0.69 190
Epimetheus Fountain, Larson (1980) 151.4 0.69 120
Mimas Herschel (1789) 186 0.94 394 0.4 1.2
Enceladus Herschel (1789) 238 1.37 502 0.8 1.2
Tethys Cassini (1684) 295 1.89 1048 7.5 1.3
Dione Cassini (1684) 377 2.74 1120 11 1.3
Rhea Cassini (1672) 527 4.52 1530 25 1.3
Titan Huygens (1655) 1222 15.95 5150 1346 1.9
Hyperion Bond, Lassell (1848) 1481 21.3 270
Iapetus Cassini (1671) 3561 79.3 1435 19 1.2
Phoebe Pickering (1898) 12,950 550 (R) 1 220
Uranus (27) Puck Voyager (1985) 86.0 0.76 170
Miranda Kuiper (1948) 130 1.41 485 0.8 1.3
Ariel Lassell (1851) 191 2.52 1160 13 1.6
Umbriel Lassell (1851) 266 4.14 1190 13 1.4
Titania Herschel (1787) 436 8.71 1610 35 1.6
Oberon Herschel (1787) 583 13.5 1550 29 1.5
Neptune (14) Despina Voyager (1989) 53 0.33 150
Galatea Voyager (1989) 62 0.40 150
Larissa Reitsema, et al (1981) 74 0.55 194
Proteus Voyager (1989) 118 1.12 420
Triton Lassell (1846) 355 5.88 (R) 2 2720 220 2.1
Nereid Kuiper (1949) 5511 360 340
Pluto (5) Charon Christy (1978) 19.7 6.39 1200 1.7
Styx Showalter et al (2012) 42 20 20
Nix Weaver et al (2005) 48 24 46 2.1
Kerberos Showalter et al (2011) 58 24 28 1.4
Hydra Weaver et al (2005) 65 38 61 0.8
Eris (1) Dysnomea Brown et al (2005) 38 16 684
Makemake (1) (MK2) Parker et al (2016) 160
Haumea (2) Hi’iaka Brown et al (2005) 50 49 400
Namaka Brown et al (2005) 39 35 200

Footnotes

    R stands for retrograde rotation (backward from the direction that most objects in the solar system revolve and rotate). R stands for retrograde rotation (backward from the direction that most objects in the solar system revolve and rotate).

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    Some Moons Could Have Moons of Their Own

    By: Christopher Crockett October 19, 2018 0

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    Four solar system satellites — and one putative exomoon — might be big enough and far enough from their home worlds to hold onto tiny moons for billions of years.

    Saturn's moon Iapetus, seen in this picture from the Cassini spacecraft, is one of four moons in the solar system that could potentially hold submoons in stable orbits.
    NASA / JPL-Caltech / Space Science Institute

    Moons, planets, and stars seem to follow a clear hierarchy: Moons orbit planets, and planets orbit stars. But now two researchers are asking if a moon can have moons of its own.

    If the primary moon is large enough or orbiting far enough from its planet, then a “submoon” could survive in a stable orbit for billions of years, the researchers report October 8th on the astronomy preprint arXiv. What’s more, some of the moons in our own solar system seem to fit the bill.

    “I was originally answering a question my son asked me four years ago,” says Juna Kollmeier (Carnegie Observatories), who coauthored the paper with Sean Raymond (University of Bordeaux, France). The mounting evidence for a Neptune-size moon orbiting the Jupiter-size exoplanet Kepler-1625b spurred the researchers to get their ideas out to the community.

    The challenge for a submoon is to find an orbit that balances the competing influences of the parent moon and the host planet. A submoon would raise tides on the moon that it orbits, which would feedback to the submoon and change its orbit. A nearby planet complicates matters by gravitationally fiddling with the speed at which the moon rotates, which would also change the orbit of the submoon.

    “There’s a Goldilocks zone where you have stable orbits,” Kollmeier explains. “If the submoon gets too close, it will crash into its host moon. If it orbits too far out, it becomes gravitationally unbound.”

    Using previous analyses of moons around planets snuggled up to their stars as a starting point, Kollmeier and Raymond calculated how big a moon would need to be to hold on to a roughly 10-kilometer-wide submoon over the age of the solar system, about 4.6 billion years. The results vary — the bigger the moon, for example, the closer it can be to the planet. In a few cases, however, there is a confluence of moon size and orbit in which a submoon could survive.

    Four moons in our solar system qualify: Earth’s moon Jupiter’s moon Callisto and two of Saturn’s moons, Iapetus and Titan. The bloated satellite of Kepler-1625b might also work, although the researchers note that the apparent high inclination of the moon’s orbit might lead to complications.

    The idea that a moon could have a tag-along isn’t all that crazy, says Alex Teachey (Columbia University), who helped build the case for a satellite around Kepler-1625b. “The physics behind calculating the stability of a submoon…is straightforward,” he says. Though he notes that submoons would be impossible to detect in other solar systems for the foreseeable future — even a satellite of a Neptune-size moon would likely be smaller than the dwarf planet Ceres.

    “A more interesting question is whether we could detect one of these objects in our solar system, or if there might be some evidence that one of these submoons once existed,” says Teachey. Some researchers have speculated that the 20-kilometer-high ridge that wraps around Saturn’s moon Iapetus might be the remains of a submoon that was torn apart by the satellite’s gravity and then rained down on the surface. “That’s a very intriguing hypothesis.”


    Planets and their Satellites (Moons)

    There are total 8 planets in our solar system & all the planets revolve around the sun in the anticlockwise direction i.e. West to East except Venus & Uranus, they both revolve in the clockwise direction i.e. East to West.

    Inner planet or Terrestrial Planets: Mercury, Venus, Earth, Mars.

    Outer planet or Jovian planet : Jupiter, Saturn, Uranus, Neptune.

    List of planets according to their Size: Jupiter, Saturn, Uranus, Neptune, Earth, Venus, Mars, Mercury.

    Dwarf Planets: Pluto, Ceres, Eris, Makemake, Haumea.


    The Solar System’s planets and officially recognized dwarf planets are known to be orbited by 194 natural satellites, or moons. 19 moons in the Solar System are large enough to be gravitationally rounded, and thus would be considered planets or dwarf planets if they were in direct orbit around the Sun.

    Moons are classed in two separate categories according to their orbits: regular moons, which have prograde orbits (they orbit in the direction of their planets’ rotation) and lie close to the plane of their equators, and irregular moons, whose orbits can be pro- or retrograde (against the direction of their planets’ rotation) and often lie at extreme angles to their planets’ equators. Irregular moons are probably minor planets that have been captured from surrounding space. Most irregular moons are less than 10 kilometers (6.2 mi) in diameter.


    2 Answers 2

    Chistiaan Huygens in 1656 is the first documented evidence.

    The invention of the telescope limits this to after 1610. Since Galileo was the first to observe such objects, it was Kepler who in 1611 called them satellites in his Narratio de observatis a se quatuor Iovis Satellitibus erronibus. Which is about 'the Satellites wandering about Jupiter'.

    The comparison to Earth's moon was then made by Huygens, who called Saturn's Titan a/his "luna" and provided a rationale for making this comparison:

    Saturnius hic mundus adferat: si enim gravaté olim isti systemati assentientibus, scrupulum demere potuerunt quaternae circa Iovem repertae Lunae manifestius utiq nunc eos convincet unica illa circa Saturnum oberrans, atque ob hoc ipsum quod unica est, nostratis Lunas similitudinem magis exprimens ut omittam nunc aliam quoque Saturnij globi cum hoc nostro cognationem, quam in simili axium utriusque inclinatione invenient Astronomiae periti.[…]
    — (archive.org)

    1656 – De Saturni Luna observatio nova (About the new observation of the moon of Saturn – discovery of Titan)

    As confirmed by this article:

    Christiaan Huygens, the discoverer of Titan, was the first to use the term moon for such objects, calling Titan Luna Saturni or Luna Saturnia – "Saturn's moon" or "The Saturnian moon", because it stood in the same relation to Saturn as the Moon did to the Earth.
    — Gravity Wiki: Natural satellite

    Apparently the earliest surviving copy of that text is found in a history book about the invention of telescopes, published almost immediately after Huygens first observation and conclusion, Huygen's text just slapped on for good measure to increase the length of the book.

    […]

    — Petrus Borellus: "De vero telescopii inventore cum brevi omnium conspiciliorum historia ubi de eorum confectione, ac usu, seu de effectibus agitur, novaque quaedam circa ea proponuntur, accessit etiam centuria observationum microcospicarum", Adrian Vlaaacq: Gent, 1655 (sic! on archive.org). (archive.org), Text printed with date of "March 5, 1656", page number on page: 62, page number in PDF: 148, original pamphlet 4 pages long. English translation in the Hartlib Papers.)

    A note on the timeline of confusing dates: Huygens discovered the object we now call Titan in March 1655, published a rushed but cautious pamphlet already calling it "Saturn's moon" in The Hague in March 1656. He did this because he wasn't really sure about all he concluded from his discovery but wanted to assure his primacy on this discovery in a time before copyright.

    In that Latin paper we see all the terminology current at the time. Those objects around Jupiter were the most obvious to compare and those are called variously "star" (stellulam), "satellite" (novus Saturni satelles), "planet" (planeta), "Medicaen planet" (Mediceos Jovi |named after the Medici), "companion", "follower". He already concludes that neither Jupiter's nor Saturn's 'planets' are properly called 'planets', as they are different from those in orbiting not the sun, but orbiting an object that orbits the sun. A difference in properties he claims no other astronomer before had recognised nor taken into account.

    But as the very title of the pamphlet shows, his synonym Moon=satellite was already there, and within the text he just goes on to make this comparison:

    Caeterum mihi novum Saturniae lunae phaenomenon ad haec quoque viam aperuit
    (However, this new phenomenon of Saturn's moon…)

    It took a little while longer for him to publish his full treatise on why the moon of Saturn is really much like Earth's moon, together with his explanation of Saturn's rings in his Systema Saturnium in 1659.

    In this we find his explanation, him still juggling with other terminology of planets, star, satellite, for the 'new', 'Saturn's moon', and the moons around Jupiter:

    Now I was greatly helped in this matter not only by those more genuine phases, but also by the motion of Saturn's Moon, which I observed from the beginning indeed it was the revolution of this Moon around Saturn that first caused to dawn upon me the hope of constructing the hypothesis. The nature of this hypothesis I will proceed to explain in what follows.

    When, then, I had discovered that the new planet revolved around Saturn in a period of sixteen days, I thought that without any doubt Saturn rotated on his own axis in even less time. For even before this I had always believed that the other primary planets were like our Earth in this respect that each rotated on its own axis, and so the entire surface rejoiced in the light of the Sun, a part at a time and, more than this, I believe that in general the arrangement with the large bodies of the world was such that those around which smaller bodies revolved, having themselves a central position, had also a shorter period of rotation. Thus the Sun, its spots declare, rotates on its own axis in about twenty-six days but around the Sun the various planets, among which the Earth is also to be reckoned, complete their courses in times varying as their distances. Again, this Earth rotates in daily course, and around the Earth the Moon circles with monthly motion. Around the planet Jupiter four smaller planets, that is to say Moons, revolve, subject to this same law, under which the velocities increase as the distances diminish. Whence, indeed, we must conclude perhaps that Jupiter rotates in a shorter time than 24 hours, since his nearest Moon requires less than two days. Now having long since learned all these facts, I concluded even then that Saturn must have a similar motion. But it was my observation in regard to his satellite that gave me the information about the velocity of his motion of rotarion. The fact that the satellite completes its orbit in sixteen days leads to the conclusion that Saturn, being in the centre of the satellite's orbit, rotates in much less time. Furthermore, the following conclusion seemed reasonable: that all the celestial matter that lies between Saturn and his satellite is subject to the same motion, in this way that the nearer it is to Saturn, the nearer it approaches Saturn's velocity. Whence, finally, the following resulted: the appendages also, or arms, of Saturn are either joined and attached to the globular body at its middle and go around with it, or, if they are separated by a certain distance, still revolve at a rate not much inferior to that of Saturn.
    — In 1659 Christiaan Huygens published an article on Saturn's Ring in Systema Saturnium. The translation below is based on that made by J H Walden in 1928.

    A nice outline of the events unfolding is to be read in the title:
    — Albert van Helden: "'Annulo Cingitur': The Solution to the Problem of Saturn", Journal for the History of Astronomy, Vol. 5, p.155, 1974.

    This was for the concept of using a word for our moon to describe other celestial bodies that are natural satellites to other planets. But that went all on in Latin, the language Huygens used.

    In English we see the Oxford English Dictionary give the earliest attestation at 1665 (as shown in justCal's answer with the following description:

    1665: Phil. Trans. I. 72 “The Conformity of these Moons with our Moon.” – OED 2nd edition

    This is however preceded by at least Robert Hooke's book Micrographia, which was published in the same year, albeit already in January, and as per imprint was ordered into printing on November 23. 1664:



    This will seem much more consonant to the rest of the secundary Planets for the highest of Jupiter's Moons is between twenty and thirty Jovial Semidiameters distant from the Center of Jupiter and the Moons of Saturn much about the same number of Saturnial Semidiameters from the Center of that Planet. (p240)
    — Robert Hooke: "Micrographia", January 1665. (archive.org)

    Since the earliest pamphlet by Huygens was also sent to England (as in the Hartlib-source link above), where it might have been translated and shown around early, and surely discussed in the local tongue, and both the Philosophical Transactions as well as Hooke use it without much explanation: an even earlier date seems quite likely for a direct usage of 'moons' in this sense in English.


    Uranian Satellites

    (in order by distance from planet)

    Holman, Kavelaars & Milisavljevic, 2001

    Uranus and its five major moons are depicted in this montage of images acquired by the Voyager 2 spacecraft during its January 1986 flyby of the planet. The moons, counterclockwise from bottom right, are Ariel, Miranda, Titania, Oberon and Umbriel.

    Miranda is the smallest of the five major satellites of Uranus, measuring just 480 kilometers (300 miles) in diameter. Voyager 2 passed between Miranda and Uranus during 1986, and returned this color composite of the moon.

    The carved dark streaks on the surface of this icy moon turned out to be ridges and valleys in higher resolution images.

    This high resolution image of Miranda was taken from a distance of 31,000 kilometers (19,000 miles), and shows a cratered surface broken by cliffs up to 20 kilometers (12 miles) high. Such fractures and grooves in the satellite's surface indicate a complex geologic history.

    Titania is the largest satellite of Uranus. This image of Titania is a composite of 2 images taken by Voyager 2 on January 24, 1986.

    Before the 1986 Voyager encounter, Uranus was known to have five moons. Those farthest from the planet have the highest density, and may consist of a silicate core covered by a thin, ice-rich crust. The moons show increasingly complex surface features closer to the planet.

    The next moon out from Miranda, Ariel, is the brightest of the Uranian moons, and has the highest density (1.65 g/cm 3 ).

    Umbriel is the darkest of the Uranian moons, and has an icy crust pockmarked by craters. The surface is uniform in reflectivity, with the exception of a bright ring (top), which may be an impact crater.

    The outermost of the five major satellites, Oberon, appears much like the satellites. Oberon orbits Uranus at more than twice the distance of our own Moon from Earth.

    Ten new moons of Uranus were discovered by Voyager in 1985 and 1986. Puck is only 150 kilometers (93 miles) across, and is the largest of the ten. These ten minor satellites all circle Uranus inside the orbit of Miranda.

    See this exhibition on display at the

    A gift to the National Air and Space Museum is a gift to the nation, the world, and the future. Support the Campaign.


    Interplanetary Spacecraft

    The exploration of the solar system has been carried out largely by robot spacecraft sent to the other planets. To escape Earth, these craft must achieve escape speed, the speed needed to move away from Earth forever, which is about 11 kilometers per second (about 25,000 miles per hour). After escaping Earth, these craft coast to their targets, subject only to minor trajectory adjustments provided by small thruster rockets on board. In interplanetary flight, these spacecraft follow orbits around the Sun that are modified only when they pass near one of the planets.

    As it comes close to its target, a spacecraft is deflected by the planet’s gravitational force into a modified orbit, either gaining or losing energy in the process. Spacecraft controllers have actually been able to use a planet’s gravity to redirect a flyby spacecraft to a second target. For example, Voyager 2 used a series of gravity-assisted encounters to yield successive flybys of Jupiter (1979), Saturn (1980), Uranus (1986), and Neptune (1989). The Galileo spacecraft, launched in 1989, flew past Venus once and Earth twice to gain the energy required to reach its ultimate goal of orbiting Jupiter.

    If we wish to orbit a planet, we must slow the spacecraft with a rocket when the spacecraft is near its destination, allowing it to be captured into an elliptical orbit. Additional rocket thrust is required to bring a vehicle down from orbit for a landing on the surface. Finally, if a return trip to Earth is planned, the landed payload must include enough propulsive power to repeat the entire process in reverse.

    Key Concepts and Summary

    The orbit of an artificial satellite depends on the circumstances of its launch. The circular satellite velocity needed to orbit Earth’s surface is 8 kilometers per second, and the escape speed from our planet is 11 kilometers per second. There are many possible interplanetary trajectories, including those that use gravity-assisted flybys of one object to redirect the spacecraft toward its next target.


    3.5 Motions of Satellites and Spacecraft

    Newton’s universal law of gravitation and Kepler’s laws describe the motions of Earth satellite s and interplanetary spacecraft as well as the planets. Sputnik, the first artificial Earth satellite, was launched by what was then called the Soviet Union on October 4, 1957. Since that time, thousands of satellites have been placed into orbit around Earth, and spacecraft have also orbited the Moon, Venus, Mars, Jupiter, Saturn, and a number of asteroids and comets.

    Once an artificial satellite is in orbit, its behavior is no different from that of a natural satellite, such as our Moon. If the satellite is high enough to be free of atmospheric friction, it will remain in orbit forever. However, although there is no difficulty in maintaining a satellite once it is in orbit, a great deal of energy is required to lift the spacecraft off Earth and accelerate it to orbital speed.

    To illustrate how a satellite is launched, imagine a gun firing a bullet horizontally from the top of a high mountain, as in Figure 3.11, which has been adapted from a similar diagram by Newton. Imagine, further, that the friction of the air could be removed and that nothing gets in the bullet’s way. Then the only force that acts on the bullet after it leaves the muzzle is the gravitational force between the bullet and Earth.

    If the bullet is fired with a velocity we can call va, the gravitational force acting upon it pulls it downward toward Earth, where it strikes the ground at point a. However, if it is given a higher muzzle velocity, vb, its higher speed carries it farther before it hits the ground at point b.

    If our bullet is given a high enough muzzle velocity, vc, the curved surface of Earth causes the ground to remain the same distance from the bullet so that the bullet falls around Earth in a complete circle. The speed needed to do this—called the circular satellite velocity—is about 8 kilometers per second, or about 17,500 miles per hour in more familiar units.

    Link to Learning

    Use the Newton’s Mountain simulator to see for yourself the effects of increasing an object’s speed. You can raise the speed until you find the speed that is just fast enough for an object to orbit the Earth, the circular satellite velocity, and also the speed at which an object leaves the Earth forever, or the escape speed.

    Each year, more than 50 new satellites are launched into orbit by such nations as Russia, the United States, China, Japan, India, and Israel, as well as by the European Space Agency (ESA), a consortium of European nations (Figure 3.12). Today, these satellites are used for weather tracking, ecology, global positioning systems, communications, and military purposes, to name a few uses. Most satellites are launched into low Earth orbit, since this requires the minimum launch energy. At the orbital speed of 8 kilometers per second, they circle the planet in about 90 minutes. Some of the very low Earth orbits are not indefinitely stable because, as Earth’s atmosphere swells from time to time, a frictional drag is generated by the atmosphere on these satellites, eventually leading to a loss of energy and “decay” of the orbit.

    Interplanetary Spacecraft

    The exploration of the solar system has been carried out largely by robot spacecraft sent to the other planets. To escape Earth, these craft must achieve escape speed , the speed needed to move away from Earth forever, which is about 11 kilometers per second (about 25,000 miles per hour). After escaping Earth, these craft coast to their targets, subject only to minor trajectory adjustments provided by small thruster rockets on board. In interplanetary flight, these spacecraft follow orbits around the Sun that are modified only when they pass near one of the planets.

    As it comes close to its target, a spacecraft is deflected by the planet’s gravitational force into a modified orbit, either gaining or losing energy in the process. Spacecraft controllers have actually been able to use a planet’s gravity to redirect a flyby spacecraft to a second target. For example, Voyager 2 used a series of gravity-assisted encounters to yield successive flybys of Jupiter (1979), Saturn (1980), Uranus (1986), and Neptune (1989). The Galileo spacecraft, launched in 1989, flew past Venus once and Earth twice to gain the energy required to reach its ultimate goal of orbiting Jupiter.

    If we wish to orbit a planet, we must slow the spacecraft with a rocket when the spacecraft is near its destination, allowing it to be captured into an elliptical orbit. Additional rocket thrust is required to bring a vehicle down from orbit for a landing on the surface. Finally, if a return trip to Earth is planned, the landed payload must include enough propulsive power to repeat the entire process in reverse.


    Titania

    Our editors will review what you’ve submitted and determine whether to revise the article.

    Titania, largest of the moons of Uranus. It was first detected telescopically in 1787 by the English astronomer William Herschel, who had discovered Uranus itself six years earlier. Titania was named by William’s son, John Herschel, for a character in William Shakespeare’s play A Midsummer Night’s Dream.

    Titania orbits at a mean distance of 435,840 km (270,820 miles) from the centre of Uranus, which makes it the second outermost of the planet’s major moons. Its orbital period is 8.706 days, as is its rotational period. It is thus in synchronous rotation, keeping the same face toward the planet and the same face forward in its orbit. Its diameter is 1,578 km (980 miles), and it has a density of about 1.71 grams per cubic cm. Titania appears to be composed of equal parts water ice and rocky material a small amount of frozen methane is probably present as well. (For comparative data about Titania and other Uranian satellites, see the table.)


    Saturn's impact on the solar system

    As the most massive planet in the solar system after Jupiter, the pull of Saturn's gravity has helped shape the fate of our solar system. It may have helped violently hurl Neptune and Uranus outward. Along with Jupiter, it might also have slung a barrage of debris toward the inner planets early in the system's history.

    Scientists are still learning about how gas giants form, and run models on early solar system formation to understand the role that Jupiter, Saturn and other planets play in our solar system. A 2017 study suggests that Saturn, more so than Jupiter, steers dangerous asteroids away from Earth.


    Astronomy

    On the first Saturday in February 2013, the general public is invited to attend the 10th Annual Dark Sky Festival at Harmony, an evening of celebration and education with a primary focus on the benefits of a night sky free from the effects of excessive artificial lighting. The purpose of the event is to expose people of all ages to the marvels of astronomy and the importance of protecting dark skies --- not just for astronomy purposes, but also for the values that darkness provides to area wildlife. Now in it’s tenth year, this family-friendly festival is FREE and open to all. Festivities begin at 5 p.m. and continue until 10 p.m.


    “It has been a wonderful experience watching our festival grow year after year, ” said Greg Golgowski, Harmony’s full-time Conservation Director. “Our hope is to increase awareness of the affects of light pollution and offer simple solutions in a fun atmosphere.”

    The event is held outdoors in low light conditions on the streets, sidewalks and park located in Harmony Town Square. Amateur astronomers from around the state set up their telescopes and invite guests to view the skies. The astronomers welcome any questions and are always more than willing to share their knowledge of the night skies.

    The 2013 event will feature:

     Speakers from NASA, Seminole State College Planetarium, International Dark Sky Association, and more

     Two mobile planetariums with on-going presentations & NASA Exhibit Display

     Over 50 telescopes for public viewing of a wide variety of planets and galaxies

     A variety of kids activities including Mad Science, demos from a variety of high school robotics clubs, Kids Zone (including a Ferris Wheel, Caterpillar Ride, Gyroscope, and more)

    In addition, there will be lots of music and food, numerous specialty booths, and presentations from scientists and other experts. Attendees may even bump into a character or two from Star Wars.