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MystiMcMuffin Vice Captain
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Posted: Wed Oct 27, 2010 6:11 pm
All the good guilds have at least one. And it seems that we've been remiss in this area, which is highly disappointing. So here it is... So if you have a question, please feel free to ask. And if you have an answer - by all means speak up. Warning: I have a built-in Smart a** detector. And I, myself, am of the royal smart a** family. So, if you go there here don't be surprised at what you might get back in return. Its only fair. Its also alot of fun!
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Posted: Wed Oct 27, 2010 7:48 pm
Can anyone tell me how far it is to Little Rock?
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MystiMcMuffin Vice Captain
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Posted: Wed Oct 27, 2010 9:23 pm
pauvre matou Can anyone tell me how far it is to Little Rock? Little Rock? Seriously??!? I know of at least 4 songs that talk about getting PAST Little Rock. As in, not stopping. LoL I don't think anyone actually wants to go to Little Rock, cuz I cant seem to work out the mileage - I keep falling asleep!
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Posted: Thu Oct 28, 2010 4:02 am
MystiMcMuffin pauvre matou Can anyone tell me how far it is to Little Rock? Little Rock? Seriously??!? I know of at least 4 songs that talk about getting PAST Little Rock. As in, not stopping. LoL I don't think anyone actually wants to go to Little Rock, cuz I cant seem to work out the mileage - I keep falling asleep! Actually, this is a musical reference from what is considered one of the first bluegrass recordings: (furious banjo) "Hello there, Stranger!" "Why, hello there, Stranger!" "Can you tell me how to get to Little Rock?" "Can I tell you how to get to Little Rock? No - you can't get there from here." (more furious banjo) "Hello there, Stranger!" "Why, hello there, Stranger!" "Can you tell me how far it is to Little Rock?" "Can I tell you how far it is to Little Rock? It's exactly three lengths of a fool - if you don't believe me, lay down and measure it sometime!"
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MystiMcMuffin Vice Captain
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Posted: Thu Oct 28, 2010 5:57 pm
LoL Actually, I knew the reference, but couldn't find the dang lyrics. To verify this, you can ask Hells, Dizzy, or Dresden - they all were witness to me fighting to find the lyrics. Failing to acquire said lyrics, I went with the smart a** to smart a** approach. Thanks for playing. xd
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Posted: Fri Oct 29, 2010 8:25 pm
MystiMcMuffin LoL Actually, I knew the reference, but couldn't find the dang lyrics. To verify this, you can ask Hells, Dizzy, or Dresden - they all were witness to me fighting to find the lyrics. Failing to acquire said lyrics, I went with the smart a** to smart a** approach. Thanks for playing. xd I did some fruitless searching, as well. I'm pretty sure it was a variation of The Arkansas Traveler Skit.
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Posted: Fri Oct 29, 2010 8:42 pm
I would like to know the proper formula for calculating a stable geosynchronous orbit.
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Posted: Sat Oct 30, 2010 8:57 am
Dresden K2 I would like to know the proper formula for calculating a stable geosynchronous orbit. 1 Determine the inclination. This value will either be pre-defined or you can get it from a satellite ground track. A satellite in geosynchronous orbit will not reach above or below the latitudes equal to the inclination. For example, if the satellite is at 50 degrees inclination, it will only go as far as plus/minus 50 degrees latitude. 2 Calculate the semi-major axis (a). Because the period (P) is 24 hrs (86.4e3 seconds) and the gravitational constant (mu) is 3.986e5 km^3/s^2, you have enough information to use the equation: P^2 = 4*pi^2 * (a^3/mu) (86.4e3)^2 = 4*pi^2 * (a*3/3.986e5) 7.537e13 = a^3 a = 42,241 km 3 Determine circular orbit elements. A geosynchronous orbit is a circular orbit and some elements are common for all circular orbits. Eccentricity is an element used to describe elongation in an elliptical orbit, so for a circular orbit, e = 0. Argument of perigee is undefined in a circular orbit because only elliptical orbits have apogees and perigees. True anomaly is also undefined because it is related to perigee as well. 4 Determine the right ascension of the ascending node. This is where the satellite crosses from the southern hemisphere into the northern hemisphere. Because a geosynchronous orbit only crosses the equator at one point, that is the location of the right ascension of the ascending node. The angle is defined between the vernal equinox and the vector of nodes, but since the Earth rotates through this coordinate system, there will be a time when zero degrees longitude is aligned with the vernal equinox. This means you can use the ascending node's longitude as the right ascension. If the longitude is negative, you must add 360 degrees to convert it to a positive angle. 5 Combine all of the orbital elements to define the static orbit. Since the orbit is circular, the semi-major axis is the radius of the orbit measured from the center of the Earth. Semi-major axis = a = 42,241 km (based on a 24 hour period) Inclination = i = 50 degrees Right ascension of the ascending node = 360 + (-110) = 250 degrees eccentricity = 0 Argument of perigee is undefined True anomaly is undefined 6 Calculate the satellite's specific mechanical energy. sm = - mu/2a sm = -3.986e5/(2*42241) sm = 4.718km^2/s^2 7 Calculate the satellite's orbital velocity. For a circular orbit, the satellite's position from the center of the earth will always equal the radius of the orbit. V = SQRT(2 * ((mu/R) + sm)) V = SQRT(2 * ((3.986e5/42241) + 4.71 cool ) V = 5.32 km/s, which is over 3 miles/sec.
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MystiMcMuffin Vice Captain
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Posted: Sat Oct 30, 2010 10:00 am
pauvre matou Dresden K2 I would like to know the proper formula for calculating a stable geosynchronous orbit. 1 Determine the inclination. This value will either be pre-defined or you can get it from a satellite ground track. A satellite in geosynchronous orbit will not reach above or below the latitudes equal to the inclination. For example, if the satellite is at 50 degrees inclination, it will only go as far as plus/minus 50 degrees latitude. 2 Calculate the semi-major axis (a). Because the period (P) is 24 hrs (86.4e3 seconds) and the gravitational constant (mu) is 3.986e5 km^3/s^2, you have enough information to use the equation: P^2 = 4*pi^2 * (a^3/mu) (86.4e3)^2 = 4*pi^2 * (a*3/3.986e5) 7.537e13 = a^3 a = 42,241 km 3 Determine circular orbit elements. A geosynchronous orbit is a circular orbit and some elements are common for all circular orbits. Eccentricity is an element used to describe elongation in an elliptical orbit, so for a circular orbit, e = 0. Argument of perigee is undefined in a circular orbit because only elliptical orbits have apogees and perigees. True anomaly is also undefined because it is related to perigee as well. 4 Determine the right ascension of the ascending node. This is where the satellite crosses from the southern hemisphere into the northern hemisphere. Because a geosynchronous orbit only crosses the equator at one point, that is the location of the right ascension of the ascending node. The angle is defined between the vernal equinox and the vector of nodes, but since the Earth rotates through this coordinate system, there will be a time when zero degrees longitude is aligned with the vernal equinox. This means you can use the ascending node's longitude as the right ascension. If the longitude is negative, you must add 360 degrees to convert it to a positive angle. 5 Combine all of the orbital elements to define the static orbit. Since the orbit is circular, the semi-major axis is the radius of the orbit measured from the center of the Earth. Semi-major axis = a = 42,241 km (based on a 24 hour period) Inclination = i = 50 degrees Right ascension of the ascending node = 360 + (-110) = 250 degrees eccentricity = 0 Argument of perigee is undefined True anomaly is undefined 6 Calculate the satellite's specific mechanical energy. sm = - mu/2a sm = -3.986e5/(2*42241) sm = 4.718km^2/s^2 7 Calculate the satellite's orbital velocity. For a circular orbit, the satellite's position from the center of the earth will always equal the radius of the orbit. V = SQRT(2 * ((mu/R) + sm)) V = SQRT(2 * ((3.986e5/42241) + 4.71 cool ) V = 5.32 km/s, which is over 3 miles/sec. *high fives* Thanks for taking that one for me, dude! LoL
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Posted: Sat Oct 30, 2010 2:11 pm
It may have been a trick Q because he did say a stable geosynchronous orbit.
I remodeled a kitchen one of NASA's top mathematicians. Our nick-name for the guy was "The Bug".
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tigris cobaltchaos Vice Captain
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Posted: Sat Oct 30, 2010 6:30 pm
gonk ....math.... "don't go back to Rockville and waste another year"
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Posted: Sun Oct 31, 2010 8:15 am
pauvre matou It may have been a trick Q because he did say a stable geosynchronous orbit. I remodeled a kitchen one of NASA's top mathematicians. Our nick-name for the guy was "The Bug". Got caught can have a stable orbit if everything was truly a constant but seeing that not even the weight of the orbiting object is truly stable (dust and particles collecting on the object) all orbits have to be adjusted by factors that can only be calculated after they happen. On to my next Q ... What is the true origin of the word slave?
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Posted: Sun Oct 31, 2010 11:55 am
Dresden K2 On to my next Q ... What is the true origin of the word slave? slave (n.) late 13c., "person who is the property of another," from O.Fr. esclave (13c.), from M.L. Sclavus "slave" (cf. It. schiavo, Fr. esclave, Sp. esclavo), originally "Slav" (see Slav), so called because of the many Slavs sold into slavery by conquering peoples. This sense development arose in the consequence of the wars waged by Otto the Great and his successors against the Slavs, a great number of whom they took captive and sold into slavery. [Klein]
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Posted: Sun Oct 31, 2010 1:59 pm
pauvre matou Dresden K2 On to my next Q ... What is the true origin of the word slave? slave (n.) late 13c., "person who is the property of another," from O.Fr. esclave (13c.), from M.L. Sclavus "slave" (cf. It. schiavo, Fr. esclave, Sp. esclavo), originally "Slav" (see Slav), so called because of the many Slavs sold into slavery by conquering peoples. This sense development arose in the consequence of the wars waged by Otto the Great and his successors against the Slavs, a great number of whom they took captive and sold into slavery. [Klein] Close but those are modern dictionary definitions I was looking for the origin ... that goes back to the 9th c AD when the Muslims in what is now Spain would raid and capture the original slavia (kergonic decedents who lived in eastern Europe) and referred to them as Slavs hence the birth of the word Slave. Side-note -- most of these were used as soldiers and not servants or basic forced labor.
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Posted: Sun Oct 31, 2010 8:29 pm
Well, I guess 13th century would be considered modern compared to 9th century.
Where was Moses when the lights went out?
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