Space Suits and Tugs - Atomic Rockets. This is from Robust Lunar Exploration Using an Efficient Lunar Lander Derived from Existing Upper Stages and A Commercially Based Lunar Architecture, both from United Launch Alliance (ULA).
The ULA's Advanced Common Evolved Stage (ACES) is basically a ULA standard propulsion bus. The idea is to avoid relying upon gigantic expensive launch vehicles such as the Ares_V (not to mention the fact that the Ares V doesn't exist yet). ULA proposes using the tiny ACES refueled with the miracle of orbital propellant depots so that smaller inexpensive commercial launch vehicles can be used instead of the expensive Ares V. Without the support of orbital propellant depots, the ACES would have to lug along all the propellant needed for the entire freaking mission. Browse our quotes collection, once you found your desired one, create beautiful quote as image and share on Facebook, Twitter & Pinterest. This web page is dedicated to our good friend, retired armored vehicle engineer Bill Criswell who passed away a few years ago. A courageous and wise voice of reason. Since Every gram counts, this would bloat the ACES design to the point where there was no choice but to use the pricy Ares V. According to the second ULA report: "This strategy leads to high infrastructure utilization, economic production rates, high demonstrated reliability and the lowest possible costs." It will also help develop the infrastructure needed not only for Lunar operations, but also missions to Near Earth Asteroids and Mars. Establishing a propellant depot at the Terra- Luna L2 point will assist exploration outside of the Terra- Luna system. Since 7. 5% of the mass being boosted to LEO is propellant, it is cheaper to use commercial launch vehicles. This also encourages conducting lunar exploration as a continuous process instead of a series of disconnected missions. In addition to using propellant depots, the strategy includes using a common propulsion stage, the ACES module. Ideally the various components of the ACES should be commodities, that is, be off- the- shelf components available from several companies instead of just from ULA or NASA. ACES 4. 1The ACES module uses its basic liquid hydrogen/liquid oxygen for main propulsion, propellant pressurization, RCS, power from fuel cells, and heat radiators. By using LH2/LOX for everything, it reduces the number of points of failure. E. g., helium tanks to pressurize the propellant, MMH/NTO for RCS, and solar panels for power are just three more systems that can break. ULA's buzzword for this concept is Integrated Vehicle Fluids. This makes the ACES module a valuable component of a modular design spacecraft. It is doing its level best to be an "Instant spacecraft kit - just add payload". The basic unit is the ACES 4. The "stretched" version, the ACES 7. The stretching of the design is possible since all the subsystems are concentrated on the aft- mounted equipment deck, just forwards of the engines. All that needs to be done is add side- wall segments. Due to the clever planning of the orbital propellant network, only a 4. They can handle all the necessary tasks in the mission plan. The tank has a diameter of 5 meters. It drastically reduces cryogenic propellant boil- off by a variety of methods: tank geometry, low conductivity tank structures, passive thermal protection, and vapor cooling. In addition the cryogenic propellant is subcooled so it can last longer. The tank's exposed surface is covered by a thick multi- layer insulation blanket, to reduce heating from Terra or Sol. As preveviously mentioned, the ACES has no helium pressurization system, hydrazine fed RCS, nor solar power panels. Instead these functions are performed using the already present supply of LH2/LOX. But the major feature is the tanks are designed to be refilled with propellants once in space. Practically no existing spacecraft can do this, but it is a sine qua non for utilizing orbital propellant depots. ACES mounts 2 to 4 RL1. In the lunar mission plan, the ACES module will be used for four primary in- space mission functions: As service module propulsion system for an ACES 4. Orion spcecraft. As the descent propulsion system for an ACES 4. Altair lunar lander. As an ACES 7. 1 propellant tanker. As a component of an ACES 7. LH2 capacity)ACES/Orion spcecraft. Add to an ACES 4. ECLSS) Module and an Orion Crew Module, and you have an Orion spacecraft. The ACES 4. 1 is acting as a "service module" for the Orion Crew Module. The ACES provides the propulsion, half of the RCS (other half is on Orion), electrical power, and heat radiator. The ECLSS provides the Orion Crew Module with N2 replenishment, CO2 scrubbing, and voice communication. ACES/Tanker. This is a "stretched" version of the ACES 4. ACES 7. 1 contains 7. It will be used as a propellant tanker (7. LH2 storage section of an depot (1. ACES/Depot. This is an ACES 4. ACES 7. 1. The ACES 7. LH2 storage, and the ACES 4. LOX storage. The modified ACES 7. LH2) and liquid oxygen (LOX) shifted in order to maximize LH2 storage. The engines are removed and a deployable sunshield is installed. The depot has multiple interfaces for transferring propellant to and from the depot tanks. It can also supply power and support services to docked vehicles for extended periods. The proposed orbital propellant depot network will have one depot in LEO and the other at L2. Yes, I am aware that other experts are of the opinion that L1 is superior to L2 when it comes to siteing Terra- Luna propellant depots. However ULA wants the depot at L2 to assist missions to Mars and other points outside the Terra- Luna system. An L2 depot can replace an L1 depot, but an L1 depot cannot replace an L2 depot. The entire depot structure (both ACES 4. ACES 7. 1) is launched with the ACES 7. Since the ACES 7. After launch into LEO, the ACES 4. It will transfer the residual LH2 into the ACES 7. LOX. Remember that the ACES 7. LH2 storage while the ACES 4. LOX. The depot will become the LEO orbital depot. Subsequent launches will fill the tanks and keep them filled. The second depot launched into LEO is destined to be installed at L2. Once it reaches LEO, the ACES 4. LH2 and LOX, since it will be used as a tug. The ACES 7. 1 section will just be filled with LH2 since it is basically payload. The ACES 4. 1 section transports the entire depot to L2. The L2 depot will be kept topped up by periodic visits from a propellant tanker based on an ACES 7. EAch LEO to L2 trip will deliver 2. Temperature conditions are very different in LEO as compared to L2. LEO is a hot place, with thermal radiation from Terra heating up the depot tanks and boiling off propellant. L2 is relatively cold. The depot uses a passive thermal protective system. It deals with the problem by being designed to primarily boil- off and vent gaseous hydrogen (since it has about ten times the thermal capacity of oxygen). It will boil- off about 2. The liquid hydrogen is used to cool off the liquid oxygen, in other words. As it turns out, objects in LEO need lots of RCS action to keep the depot in its assigned spot and not falling out of orbit to a fiery doom or something like that. The boiled- off gaseous hydrogen can be used in RCS attitude jets to prevent that unhappy fate (Isp of 3. V per day). The boil- off and station- keeping needs can be balanced. At L2 the heating rate is far less, boil- off of only one kilogram a day or so. Luckily at quasi- stable L2 the station- keeping requirements are also low. The LEO Depot will lose about 1. However, since the plan has over 3. LEO Depot in a year, the heating loss is less than 4%. ACES/Altair. For Lunar operations, a belly lander spacecraft based on the ACES 4. This is called the Dual Thrust Axis Lander (DTAL) since it has two thrust directions: aft like a tail- sitter, and dorsal like a belly- lander. The DTAL- R is a robot controled cargo landing vehicle, the DTAL- Crew is a manned cargo landing vehicle. Basic Element Mass Summary. Vehicle Element/Assembly. Dry Massmetric tons. Propellantmetric tons. Basic ACES 4. 15. Basic ACES 7. 1/ Tanker. Orion Command Module. Orion ECLSS Module. Orion Crew & Associated Cargo. Altair Cargo/Descent Module. Altair Ascender. 3. Altair Light Cargo. Altair Heavy Cargo. Depot Systems Module. ACES Depot (2 docked ACES)1. Vehicle Assembly Mass & Performance Summary. Vehicle Assembly. Total Massmetric tons. Delta VCapacitym/s. Nominal. Delta VDemandm/s. Nominal. Residual. Propellant. ACES/Orion @ LEO Departure. ACES/Orion @ L2 Departure. ACES /Altair @ LEO Departure. ACES/Altair @ L2 Departure. ACES/Altair Cargo @ LEO Departure. ACES/Altair Cargo @ L2 Departure. Variable. 2,9. 00. ACES/Tanker @ LEO Departure. Ascender @ Lunar Departure. Lunar Transport Operations. Solstice and the Scientist Lausanne Lab. Someone you know is running the St. Jude Marathon! Click below to see who.. St. Jude Children's Research Hospital. TR/Heroes/Heroes; jsessionid=0. NONCE_TOKEN=0. F9. ADB6. F4. 18. 54. DAD5. 96. B1. 20. F2. A7. 92. 7& px=2. Tuesday, September 2. The change of seasons arrived Friday. Happy Autumn. Friday was the "autumnal equinox." Day and night are equal: 1. From now until late December, Earth's North Pole begins to face away from the sun on its orbital journey through space. Thursday is Rosh Hashana, the happy Jewish New Year celebration. So, Happy Jewish New Year: Shanah Tova! Enjoy some apples & honey today. This is a very active hurricane season. Hurricane Maria has struck Puerto Rico. Power is out on the island. What was the deadliest hurricane? Its name was Hurricane Camille, in 1. Yours truly will offer a Saturday Science Program at Collierville Library on Saturday, 9/2. We expect to have a wonderful time! The leftovers (remnants) of Hurricane Irma have come & gone. When it weakened over land, it became a "cyclone." That's a word that means "swirling low pressure" as measured with a barometer. It brought us about an inch of rain. Welcome, September! Birthstone: Sapphire. Flower: Astor. We are missing some rocks & minerals from our collection in the lab. We are missing iron pyrite (sparkly fool's gold), our meteorite from Argentina, bismuth crystals, lead ore, & turritella (several shiny brown/multicolored small fossil stones). The rocks & minerals are for everyone to enjoy. Have you seen them? We would like to get them back. Thank you! Monday was the 1. September 1. 1, 2. It was a day of attack on the United States. But it was also a day of heroism. Please read an account of it under "stories" on this web site. If you get up early, try to go outside & look to the east. If the weather is clear, then you'll see a bright, shining point of light. It is planet Venus! We are blessed with fair weather for the Mid- South this week. Before dawn, Constellation Orion may be seen in the southern sky. But storms are brewing in the Atlantic Ocean. Often, we see powerful hurricanes at the end of summer. But why? We recall that a hurricane's "fuel" is really warm water, above 8. Fahrenheit. At this time of year, the sun has been warming the water for a few months - - all summer long. This factor contributes to the strength of a hurricane. Even if you were to go to Florida in November, you could probably still swim in fairly warm waters. Water takes a long time to "heat up," and it takes a long time to "cool down." Labor Day: A National Holiday. On this day, government offices, banks, & schools are closed. On this day, we honor the working people of our country. Work - - labor - - is our gift to others. It is really a gift of love from ourselves to the world to help make it a better place. Happy Labor Day! Hurricane Harvey hit the east coast of Texas. It dropped a great deal of rain. Hurricanes may be thought of as "heat storms." They are caused by the sun's heating the waters of the ocean. Earth's spinning "kicks" hurricanes into motion. Hurricanes are the biggest storms on the planet. It was very good to see so many of our Lausanne parents on Parents Night! The solar eclipse came on Monday, August 2. It began (over Memphis skies) at 1. Clouds were blowing over Lausanne but they did break a few times to the cheers of us all! We were able to see a few minutes of the solar eclipse! Keep your eclipse glasses as a souvenir. August is named after the Roman emperor, Augustus Caesar. This week, in 1. 93. Judy Garland recorded "Somewhere Over the Rainbow." It was written by Harold Arlen. Neil Armstrong & Buzz Aldrin blasted off from the Moon to meet their fellow crewman, Michael Collins, for the return flight to Earth. Their Apollo 1. There is no wind or rain on the Moon to change even their footprints. "Ora et labora." Do you know what that means? It is Latin (a language I learned in elementary school) for "Prayer and work." Not a bad motto! It was said by a man named Benedict who lived in the mountains of Italy 1,5. His home is still there; it is called Monte Casino. I visited there; it's very peaceful and beautiful. Happy 4th of July! Happy Birthday, America. We are 2. There is a star in the summer sky, Spica. Spica shines brightly. Its light travels through space at 1. The light from Spica left the star 2. We see that light tonight. Spica is "2. Earth. To locate Spica, find the Big Dipper. Then follow the handle of the Dipper away from the bowl. The first bright star you see, as you follow that curve, is Arcturus. The next bright star along that curve is Spica. We may remember it this way: "Discover the Dipper, Arc to Arcturus, Speed to Spica." I am sad to report that our rescued hawk died during the night at the animal hospital. I do not know the exact cause, but will seek more information from the good folks at the Raptor Center at Shelby Farms. I will post more about it when I can. A Hawk at School. On Wednesday we saw a hawk on the ground in a nearby yard, close to school. Our security guard, Mr. Mark, and I, saw him. The bird appeared to have a broken right leg. He flew up into a tree. His leg was hurt, but he seemed to fly well. We were able to borrow a ladder & put a net on him. I took him to the Summer Avenue Animal Emergency Clinic. We will check on him today! A Bright Star & the Big Dipper. Tonight after dark, we may look to the north, about 3. The North Star (Polaris) is there. Polaris is not especially bright, so you have to look carefully. Just to the left (west) of Polaris is the Big Dipper. The "bowl" of the Dipper points to Polaris. If we "follow the handle" away from the Big Dipper, we will find the bright star Arcturus. We may remember it with this phrase, "Arc to Arcturus." Arcturus' name means "Guardian of the Bear." Arcturus is the brightest star in the northern hemisphere. Sirius is brighter, but it's in the southern hemisphere. Arcturus is 3. Welcome, sunshine! Cool winds from the north are bringing us comfortable air with less water vapor (less humidity). When air is cooler, this cooler air cannot contain as much humidity as can warmer air. If you are up very early, when it's still dark, look to the eastern sky. The bright light is planet Venus. It shines with reflected sunlight - - off its bright cloud cover. Happy 1st week of Summer! The 1st day was marked by the apparent position of the sun in the sky - - the sun is highest at this time. If you could see the stars behind the sun, you'd see the constellation "Cancer" (the crab). The sun, we say, is ".. Tropic of Cancer." Higher sun in the sky, longer days, shorter nights. That's summer! The weather is very hot in Phoenix, Arizona. It may reach 1. It will be so hot that some airplanes will not fly. Why not? Warm air has moving (kinetic) energy. It spreads out, and becomes thin (less dense). The wing of a plane needs air to develop lift. When there's not enough air, then there's not enough lift. Some planes are grounded. Spring is drawing to a close. Yesterday was the last full day of spring. Official summer begins Tuesday evening. It all has to do with the apparent position of the sun in the sky. The sun will reach the Tropic of Cancer in the sky.. Tuesday. Father's Day 2. This was the 1. 07th celebration of Father's Day. The idea came from a lady named Sonora Smart Dodd. Sonora & her 5 siblings were raised by her father, William Jackson Smart. Sonora's mother died in childbirth in 1. Spokane, Washington. Sonora was in church - - on Mother's Day, 1. Why isn't there a Father's Day?" she wondered. So, she worked with her local church people and the local YWCA to get them all to recognize a "Father's Day" in 1. Sonora knew her father succeeded in raising the family with "leadership and love."Happy Father's Day! France sent the USA a gift: The Statue of Liberty. A boat brought her over & placed her on Ellis Island, New York. We have probably heard that "heat rises." Does it? It might be better to think of it this way: heavier things push up (or "buoy up") lighter things. When sun shines on the ground, the ground absorbs heat, and the air next to the ground warms up, too. Warm air moves and is lighter than cool air. So, cool air sinks, pushing up the warmer air. Rising air spreads out and becomes cooler. Have you ever been up a mountain?
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