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tlbs101
2004-Sep-14, 08:04 PM
APOD (http://antwrp.gsfc.nasa.gov/apod/astropix.html)

Read the picture caption text. It says that Genesis orbited the Sun. I thought Genesis orbited the Earth-Sun L1 point.

ToSeek
2004-Sep-14, 08:11 PM
It did. (http://www.genesismission.org/mission/LOI.html)

ngc3314
2004-Sep-14, 08:20 PM
APOD (http://antwrp.gsfc.nasa.gov/apod/astropix.html)

Read the picture caption text. It says that Genesis orbited the Sun. I thought Genesis orbited the Earth-Sun L1 point.

I might be inclined to give them a pass on this one - in a heliocentric frame, it did describe a slightly bobbling path with period of one year and spanning all heliocentric longitudes...

harlequin
2004-Sep-14, 09:34 PM
APOD (http://antwrp.gsfc.nasa.gov/apod/astropix.html)

Read the picture caption text. It says that Genesis orbited the Sun. I thought Genesis orbited the Earth-Sun L1 point.

I might be inclined to give them a pass on this one - in a heliocentric frame, it did describe a slightly bobbling path with period of one year and spanning all heliocentric longitudes...

Would not the Moon also fit your description? :-)

Argos
2004-Sep-14, 10:17 PM
It says that Genesis orbited the Sun. I thought Genesis orbited the Earth-Sun L1 point.

Doesn´t L1 orbit the Sun? (http://www.genesismission.org/mission/lagrangepoints.html) :)

Bozola
2004-Sep-14, 10:39 PM
I vaguely remember that ALL Lagrange points orbit the sun.

tracer
2004-Sep-15, 12:45 AM
The Lagrange point between Alpha Centauri A and Alpha Centauri B doesn't orbit the sun. :P

kanon14
2004-Sep-15, 01:03 AM
I read the links above but i still don't get how to calculate L1, L2, and L3 points in the system.


Objects can settle in an orbit around a Lagrange point. Orbits around the three collinear points, L1, L2, and L3, are unstable.
does that means orbiting around the L1 Genesis was on an unstable orbit??

ToSeek
2004-Sep-15, 01:59 AM
I read the links above but i still don't get how to calculate L1, L2, and L3 points in the system.


Objects can settle in an orbit around a Lagrange point. Orbits around the three collinear points, L1, L2, and L3, are unstable.
does that means orbiting around the L1 Genesis was on an unstable orbit??

Yes. According to the press kit, "Small thrusters will fire every eight weeks to maintain the halo orbit."

milli360
2004-Sep-15, 08:13 AM
harlequin:


APOD (http://antwrp.gsfc.nasa.gov/apod/astropix.html)

Read the picture caption text. It says that Genesis orbited the Sun. I thought Genesis orbited the Earth-Sun L1 point.

I might be inclined to give them a pass on this one - in a heliocentric frame, it did describe a slightly bobbling path with period of one year and spanning all heliocentric longitudes...

Would not the Moon also fit your description? :-)
And me, don't forget about me. I orbit the sun too.

Ut
2004-Sep-15, 12:39 PM
harlequin:


APOD (http://antwrp.gsfc.nasa.gov/apod/astropix.html)

Read the picture caption text. It says that Genesis orbited the Sun. I thought Genesis orbited the Earth-Sun L1 point.

I might be inclined to give them a pass on this one - in a heliocentric frame, it did describe a slightly bobbling path with period of one year and spanning all heliocentric longitudes...

Would not the Moon also fit your description? :-)
And me, don't forget about me. I orbit the sun too.

I'd like to see some evidence to support your claim. I don't see any citations, or links to reputable websites anywhere!

milli360
2004-Sep-15, 01:48 PM
Dick Cheney will vouch for me, we're both from Wyoming. I know that's an appeal to authority, but after all he lives at an observatory. Surely, he knows something about astronomy.

Bozola
2004-Sep-15, 04:20 PM
The Lagrange point between Alpha Centauri A and Alpha Centauri B doesn't orbit the sun. :P

smartarse.

I should have said Earth-Sun LaGrange points.

Captain Kidd
2004-Sep-15, 04:22 PM
Help an astroignorant person. What's a halo orbit? High Altitude Low Oxygen jumps keeps forcing itself into my mind when I read that.

ToSeek
2004-Sep-15, 04:43 PM
An orbit in which a spacecraft will remain in the vicinity of a Lagrangian point, following a circular or elliptical loop around that point. The first mission to take advantage of such an orbit was SOHO (Solar and Heliospheric Observatory).

- http://www.daviddarling.info/encyclopedia/H/haloorbit.html

sidmel
2004-Sep-15, 05:06 PM
High Altitude Low Oxygen jumps keeps forcing itself into my mind when I read that.


Is it that, or High Altitude Low Open? I think the idea was to drop someone off flying above radar and then they would open their shute way, way to close to the ground (for my comfort) beneath radar.

Charlie in Dayton
2004-Sep-16, 04:02 AM
High Altitude Low Oxygen jumps keeps forcing itself into my mind when I read that.


Is it that, or High Altitude Low Open? I think the idea was to drop someone off flying above radar and then they would open their shute way, way to close to the ground (for my comfort) beneath radar.

HALO = High Altitude (jump) Low Opening -- gets you down below the radar when the chute opens.

HAHO = High Altitude High Opening -- for when radar is not a problem for a chute-sized object, but would be for an aircraft, so you glide eight quadzillion miles to your landing point. Especially effective at night with dark clothing/chute and night vision equipment. They'll never see or hear you coming.

LALO = Low Altitude Low Opening -- the plane is zipping by at 200 feet (or less...), you step out the back with your drogue chute in your hand, tossing it out as you step off, which pulls your main chute open. Fastest chute opening method -- this is the procedure that BASE jumpers use.