April 2013 - AMSAT-BB - mailman.amsat.org

More On SpaceShipTwo's Flight
by B J 29 Apr '13

29 Apr '13

http://www.parabolicarc.com/2013/04/29/pictures-of-spaceshiptwos-first-powe… http://www.parabolicarc.com/2013/04/29/spaceshiptwo-completes-first-powered… http://www.virgingalactic.com/news/item/virgin-galactic-breaks-speed-of-sou… 73s Bernhard VA6BMJ @ DO33FL

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Observations From ESA's Herschel Observatory End
by B J 29 Apr '13

29 Apr '13

http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=51550 73s Bernhard VA6BMJ @ DO33FL

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Successful Powered Flight For SpaceShipTwo
by B J 29 Apr '13

29 Apr '13

http://www.newspacejournal.com/2013/04/29/spaceshiptwos-first-powered-fligh… http://spacecoalition.com/blog/spaceshiptwo-en-route-for-projected-first-po… 73s Bernhard VA6BMJ @ DO33FL

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Re: Path to HEO
by M5AKA 29 Apr '13

29 Apr '13

--- On Mon, 29/4/13, Stefan Wagener <wageners(a)gmail.com> wrote: > maybe I didn't make myself clear: > LEO (low earth orbit) from 400 to 2000km or something like that > HEO (high earth orbit) >20000km > Going from 310 to 700km in a year is not doing us anything. Romit-1 and the other CubeSats testing ion engines will definitely give us something - proof that it works in practice or an opportunity to learn from any problems / design issues that arise. Given that Space is a demanding environment I'm sure not all the ion motor CubeSats currently being developed will work as planned when deployed, it'll be a learning experience. Going from a 310 to a 700 km orbit in a year using the limited solar power generated from a standard 2U CubeSat will be a major step forward. It follows that to get up to 7200 km or even better 20000 km will take years but could be speeded up by having CubeSats with large fold-out solar panels and more powerful motor. I say CubeSats rather than Microsats because of cost, a 35 kg microsat could cost $1 million just to get into LEO. I hope the various groups that have developed ion motor CubeSats are eventually successful is getting launches to LEO to test them out. 73 Trevor M5AKA ----

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Re: Path to HEO
by Daniel Schultz 29 Apr '13

29 Apr '13

>In addition, doesn't the process getting from GTO to HEO require some form >of rapid acceleration? If yes, ion engines and solar sails are out. The main requirement for escaping from LEO is that the engine thrust must exceed the atmospheric drag force. The time required to reach a HEO orbit mainly depends on how much electrical power you can generate, more power means more thrust and a faster ride to the desired orbit. A Cubesat power budget will be somewhat limited, deployable solar panels might help somewhat. Most Cubesat launches are deliberately sent to low orbits to insure rapid reentry and burn-up to meet orbital debris requirements, that is why Cubesat launches to GTO are rare. A higher orbit will require a disposal plan, but electric propulsion can help with that too. Please see my paper in the 2012 AMSAT Symposium Proceedings. Dan Schultz N8FGV

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Orbits Questions And Satellite Safety
by Dave Marthouse 29 Apr '13

29 Apr '13

I know that the earth is surrounded by radiation belts that have the potential of damaging satellites. How dense are they and around what altitudes do they have their most harmful affects? I am going to hazard a guess that this is why higher leo satellites (let's say over 1500 miles high) haven't been launched over the years. Any information would be appreciated. Dave Marthouse N2AAM dmarthouse(a)gmail.com

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Re: Shack cleaning sale
by Glenn AA5PK 28 Apr '13

28 Apr '13

Icom AG-25 mast mount 2 meter preamp Mirage KP-1/440 70 cm GaAsFET preamp G-5500 control box and elevation rotor (no az rotor) Alinco ELH-730D 70 cm linear amp (3W in for 30W out) w/preamp Radio Shack 2 meter amp (Cat. # 19-1122) Pix available. If interested, please contact me off list. Glenn AA5PK

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nee-01 pegaso
by Lizeth Norman 28 Apr '13

28 Apr '13

See here for the latest news: http://translate.google.com/translate?sl=es&tl=en&js=n&prev=_t&hl=en&ie=UTF… 73 de Norm n3ykf (Off to oa4 in the am)

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Re: What birds
by Adrian Engele 28 Apr '13

28 Apr '13

Try this site. http://oscar.dcarr.org/ 73, Adrian AA5UK from Yahoo! Mail on Android

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Shack cleaning sale
by Glenn A. Miller 28 Apr '13

28 Apr '13

Icom AG-25 mast mount 2 meter preamp Mirage KP-1/440 70 cm GaAsFET preamp G-5500 control box and elevation rotor (no az rotor) Alinco ELH-730D 70 cm linear amp (3W in for 30W out) w/preamp Radio Shack 2 meter amp (Cat. # 19-1122) Pix available. If interested, please contact me off list. Glenn AA5PK

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