KAGUYA lunar explorer (aka SELENE) |
KAGUYA lunar explorer (aka SELENE) |
Oct 9 2007, 09:30 AM
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#91
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Founder Group: Chairman Posts: 14434 Joined: 8-February 04 Member No.: 1 |
All credit to JAXA - you guys know how to make this cool...
cover it in cameras Doug |
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Oct 9 2007, 11:43 AM
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#92
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Member Group: Members Posts: 613 Joined: 23-February 07 From: Occasionally in Columbia, MD Member No.: 1764 |
Efficiency issues using fuel resources sometimes has multiple perigee burns to increase the apogee to the required size..which is why I believe the probe did several orbits around the Earth. (I may be wrongabout why multiple burns though ) A couple of factors play in. One, ideally the delta-V should be impulsive (i.e. instantaneous, with infinite thrust) But that means infinite structural loads, and a big engine. With a real engine, the thrusting must be conducted over a finite time, i.e. a finite orbital arc. If the vehicle is spin-stabilized, and the arc is long, then the engine suffers a cosine loss in useful thrust at the ends of the arc, and so it can be more efficient to split the burn up into smaller ones (each with lower losses). There can also be issues of orbit determination or safety (e.g. that should a burn fail part way through, you arent left in some catastrophic orbit - sometimes splitting it up can avoid danger zones) but that is less likely here. |
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Oct 9 2007, 01:17 PM
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#93
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Junior Member Group: Members Posts: 52 Joined: 24-November 05 From: Tokyo Member No.: 571 |
FYI, I hope this mapping image will help you figure out where Kaguya is
Mapping by Prof. Naru Hirata (Aizu Univ.) and article by Shin-ya Matsuura. http://smatsu.air-nifty.com/lbyd/2007/10/post_38e8.html (Click the image to enlarge) |
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Oct 9 2007, 01:29 PM
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#94
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Senior Member Group: Members Posts: 3648 Joined: 1-October 05 From: Croatia Member No.: 523 |
FYI, I hope this mapping image will help you figure out where Kaguya is Mapping by Prof. Naru Hirata (Aizu Univ.) and article by Shin-ya Matsuura. I see he's using NASA World Wind there -------------------- |
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Oct 9 2007, 06:58 PM
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#95
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Member Group: Members Posts: 559 Joined: 1-May 06 From: Scotland (Ecosse, Escocia) Member No.: 759 |
Many congratulations to JAXA after the disappointments about Nozomi et al. This mission is shaping up really nicely and there is a lot to look forward to. Those images of the moon with parts of the spacecrfat in the foreground remind me of Rosetta's fly-by of Mars.... as if we the viewers are looking out from a spacercraft which we are on-board.
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Oct 10 2007, 04:02 PM
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#96
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Member Group: Members Posts: 279 Joined: 19-August 07 Member No.: 3299 |
KAGUYA (SELENE) Lunar Orbit Adjustment Maneuver (LOI4)
QUOTE The Japan Aerospace Exploration Agency (JAXA) plans to carry out a lunar orbit adjustment maneuver (LOI4) for the “KAGUYA” (SELENE) from around 9:24 a.m. on October 10, 2007 (Japan Standard Time, JST.) During the 4th LOI, Kaguya will lower from 2400 km apogee altitude to 800 km apogee altitude. The next step will free another small satelite of 50 kg: VRAD on October 12. Later, there will be two more LOI adjustments before entering the Lunar orbit at Oct 19. |
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Oct 12 2007, 01:21 AM
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#97
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Solar System Cartographer Group: Members Posts: 10229 Joined: 5-April 05 From: Canada Member No.: 227 |
VRAD (Vstar) separation coming up...
http://www.jaxa.jp/countdown/f13/topics/pd...830_vstar_e.pdf Phil -------------------- ... because the Solar System ain't gonna map itself.
Also to be found posting similar content on https://mastodon.social/@PhilStooke Maps for download (free PDF: https://upload.wikimedia.org/wikipedia/comm...Cartography.pdf NOTE: everything created by me which I post on UMSF is considered to be in the public domain (NOT CC, public domain) |
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Oct 12 2007, 12:40 PM
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#98
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Member Group: Members Posts: 559 Joined: 1-May 06 From: Scotland (Ecosse, Escocia) Member No.: 759 |
.... and the VRAD satellite has departed, now-named "OUNA" meaning an "honorable elderly woman." How nice. A couple of photos show it sliding away into the black...
VRAD separation Kenny |
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Oct 19 2007, 02:33 AM
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#99
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Solar System Cartographer Group: Members Posts: 10229 Joined: 5-April 05 From: Canada Member No.: 227 |
Getting there...
http://www.jaxa.jp/countdown/f13/topics/pd...925_loi56_e.pdf Now for the images... Phil -------------------- ... because the Solar System ain't gonna map itself.
Also to be found posting similar content on https://mastodon.social/@PhilStooke Maps for download (free PDF: https://upload.wikimedia.org/wikipedia/comm...Cartography.pdf NOTE: everything created by me which I post on UMSF is considered to be in the public domain (NOT CC, public domain) |
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Oct 21 2007, 02:56 AM
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#100
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Solar System Cartographer Group: Members Posts: 10229 Joined: 5-April 05 From: Canada Member No.: 227 |
Here's the latest - images from the monitoring camera in low orbit.
Phil http://www.jaxa.jp/press/2007/10/20071021_kaguya.pdf -------------------- ... because the Solar System ain't gonna map itself.
Also to be found posting similar content on https://mastodon.social/@PhilStooke Maps for download (free PDF: https://upload.wikimedia.org/wikipedia/comm...Cartography.pdf NOTE: everything created by me which I post on UMSF is considered to be in the public domain (NOT CC, public domain) |
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Oct 21 2007, 05:20 AM
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#101
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Junior Member Group: Members Posts: 52 Joined: 24-November 05 From: Tokyo Member No.: 571 |
You can see more images captured by the monitoring camera at:
http://www.jaxa.jp/press/2007/10/20071021_kaguya.pdf Sorry, it's written mainly in Japanese... |
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Oct 21 2007, 07:39 AM
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#103
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The Poet Dude Group: Moderator Posts: 5551 Joined: 15-March 04 From: Kendal, Cumbria, UK Member No.: 60 |
Thanks for the links to those pics nop.
Is anyone else sitting there grinning, thinking "Those are just cool!!" ? -------------------- |
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Oct 21 2007, 07:47 AM
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#104
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Member Group: Members Posts: 599 Joined: 26-August 05 Member No.: 476 |
They are indeed cool.
In http://www.jaxa.jp/press/2007/10/img/20071021_kaguya_02.jpg, that would not be Earth in the background instead of part of the spacecraft, would it? |
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Oct 21 2007, 08:09 AM
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#105
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The Poet Dude Group: Moderator Posts: 5551 Joined: 15-March 04 From: Kendal, Cumbria, UK Member No.: 60 |
I spotted that too... very nice...!
Only problem with these images is that Moon-watchers like me are going to spend hours trying to identify craters on them... !!! I'm looking out for the crater "Eddington" so I can plug both the probe's mission and my astro society in the local press! Very useful for publicity and recruitment! -------------------- |
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