KAGUYA lunar explorer (aka SELENE) Options

[Rakhir]

SELENE has now a nickname : KAGUYA.
http://www.jaxa.jp/topics/2007/06_e.html

Edit :
And Emily searched for the origin of the name
http://www.planetary.org/blog/article/00000996/

[Stephen]

SELENE has now a nickname : KAGUYA.
http://www.jaxa.jp/topics/2007/06_e.html

Edit :
And Emily searched for the origin of the name
http://www.planetary.org/blog/article/00000996/

I notice that the blog writer Leonard David at livescience.com has come to a similar conclusion. He points out that the name "Kaguya" is from an ancient Japanese tale 'Taketori Monogatari' - the tale of the Bamboo-Cutter which involves Princess Kaguya, the Moon Princess."

======
Stephen

[Guest_AlexBlackwell_*]

Kaguya Approaches Launch
By Yasunori Matogawa
June 18, 2007

[Guest_Zvezdichko_*]

How are they going to insert this into polar orbit? Given the mass of the hardware and to capabilities of the rocket I don't see how they are going to achieve this.

[mchan]

The Moon's gravity can be used to effect the plane change for entering a polar orbit around the Moon.

[spdf]

Seems like the new launch date is September 13. So not a big delay for Kaguya. (But already very hostile press )

[elakdawalla]

Is there a source somewhere on the Internet for that date? (Even if it's in Japanese?)

--Emily

[spdf]

sorry I forgot:
for the September 13 date:
http://msdb.honeywell-tsi.com/launches.asp

also JAXA released a small report which says they pushed the launch to September since they need around one month of repair.: http://www.jaxa.jp/press/2007/07/20070725_sac_kaguya.pdf
So this not such a big delay.

[nop]

http://msdb.honeywell-tsi.com/missioninfo....n=SELENE/Kaguya

NET 9/13/2007, 0135:47Z

FYI, Note that it's Not Earlier Than 9/13/2007.
The new launch window for KAGUYA is 9/13/2007-9/21/2007.
(anyway, Sept. 13 is the most probable day, I think.)

[monitorlizard]

The nice thing about lunar missions is that if you miss a launch window, you only have to wait a month for the next one to come along.

[elakdawalla]

Lots of photos of Kaguya being prepped for launch:

http://jda.jaxa.jp/jda/p3_e.php?time=N&...mp;mission=4067

(Want to blog these but Cassini has to stop sending so many great photos from Iapetus first!)

--Emily

[GravityWaves]

It will be delayed by a day due to bad weather, new launch date from Tanegashima is Sep. 14 Friday

[punkboi]

A little more than 5 hours before launch... Godspeed, Kaguya!

[Guest_Zvezdichko_*]

Rock the Moon and roll to Mars

This message may be flying today

[nprev]

I don't suppose anyone knows of a live link for the launch...? Don't know if JAXA customarily does this or not.

[lyford]

http://www.jaxa.jp/countdown/f13/live/index_e.html
It's there somewheres....
Sorry

This is it:

http://www.jaxa.jp/countdown/f13/live/weblive_e.html

No word if Lipovitan will sponsor coverage.

[nprev]

...thanks, Ly, and wouldn't you know it: I just found it & was coming back to post that same link! (I gotta be less lazy...)

Coverage should start approx. 45 minutes from now (currently 2349 GMT 13 Sept).

EDIT: Kaguya coverage is live now here! Can't understand a syllable except for "hai", but GO KAGUYA!!!!!

First time I've missed the ex in awhile...she could've translated!

EDIT2: Wow...they just showed a shot of what appeared to be a crowd of people in a shopping mall or something watching the coverage on a big TV...seems as if there's a lot of domestic public interest, which is always great to see!

EDIT3: She's up!!! SWEET launch so far...most beautiful launch site ever on a wave-breaking beach, and the high temp (29 deg C) plus undoubtedly high humidity produced this amazing shockwave donut of condensation around the payload fairing that stretched & transformed into a cylinder during max Q...really remarkable, never seen the like before. That H-2 has some serious juice! External cam showed the horizon of the Earth briefly, then cut to commentators...so far, running sweet & true.

[elakdawalla]

It's up! I blogged what I could from the English translation.. Now I have to go put the baby to bed. If anybody sees anything new on the status can you please please post it here?

--Emily

[Airbag]

10:20 PM EDT: Payload separation!

Airbag

[elakdawalla]

...and that's it for the commentary. Nothing new on the launch site home page yet. Cherilynn has promised me updates and pictures from Tokyo, though, so hopefully tonight or tomorrow I'll have more...

--Emily

[Airbag]

Got to love that low-tech approach to illustrating the launch vehicle's progress on the broadcast - a hand held clipboard with stickers for each phase (e.g. 1st stage separation) that were peeled away one by one!

Airbag

[elakdawalla]

That was pretty funny. It was a bit Python-esque -- for reasons I can't quite explain, it reminded me of the French Sheep sketch.

And when they were outside, with the hardhats, it reminded me of Japanese game shows -- I kept expecting one of the men to suddenly have to go through some "challenge."

There's something about Japan that gets utterly lost upon translation to English. Beyond foreign, it's alien. I know there are some Japanese readers of this forum -- I would love to know from one of them if Americans appear inexplicable and alien to you. And -- are Europeans less so? Or more so?

--Emily

[lyford]

Anybody know what the little orange bobbing head guy on the bottom left was? Jaxa Mascot? Generic Cute Japanese Icon?

[Subaru]

[img]Anybody know what the little orange bobbing head guy on the bottom left was? Jaxa Mascot? Generic Cute Japanese Icon?

Nohohon zoku.
... Ah, my English is poor to explain it. See Wikipedia, sorry.

[Guest_Zvezdichko_*]

When are these two orbits going to be completed and when the lunar injection burn is going to occur?

[Toma B]

Is there a replay of that spectacular launch somewhere?

[Guest_Zvezdichko_*]

Yes, it's available on nasaspaceflight.com

[Pedro_Sondas]

Hi!

This is the video of the JAXA program for the Selene launch:

http://www.sondasespaciales.com/public/arc...7%20-%20Jai.asf

(311 MB - ASF)

The flag: 0h5m30sec
Launch with a looooooong countdown: 0h47m (poor quality)
Launch Replay: 1h36m (good quality)

Hai-counter now in: 3827

[SpaceListener]

Will Kaguya arrive at Moon within 3 days? Haven't found the Kaguya's mission timing.

[jabe]

from Spaceflightnow article

SELENE will fire its largest thruster to propel itself toward the moon after completing two-and-a-half circuits around Earth. The probe will slip into an initial elliptical polar orbit around the moon about 20 days after launch, according to JAXA spokesman Satoki Kurokawa.

I can't wait for the HD camera pics of earth rise
cheers
jb

[nop]

No word if Lipovitan will sponsor coverage.

In the unofficial webcast presented by CASTY, I saw Dr. Terazono (known as the Hayabusa Lipovitan-D blogger) was drinking a bottle of Lipovitan-D

Since Lipovitan-D sensation at UMSF.com in Hayabusa touchdown, this drink unofficially emblematizes Japanese space missions. Here I show a capture from the CASTY unofficial webcast in the launch of SOLAR-B/Hinode last year; you can see Dr. Terazono was drinking it
http://photo.mywiki.jp/hayabusafan/5601/20...09-4caca34e.jpg

[nop]

Will Kaguya arrive at Moon within 3 days? Haven't found the Kaguya's mission timing.

FYI, the time format is in UTC. Stay tuned

Lift-off 14 Sept 01:31:01
SSB Ignition 14 Sept 01:31:11
SSB Burnout 14 Sept 01:32:09
SSB Jettison 14 Sept 01:32:31
SRB-A Burnout 14 Sept 01:32:56
SRB-A Jettison 14 Sept 01:33:06
Fearing Jettison 14 Sept 01:35:26
MECO 14 Sept 01:37:41
1st/2nd stages seperation 14 Sept 01:37:49
SEIG 1 14 Sept 01:37:55
SECO 1 14 Sept 01:43:08
SEIG 2 14 Sept 02:11:34
SECO 2 14 Sept 02:15:03
SELENE Seperation 14 Sept 02:16:33
Sun Acquisition 14 Sept 02:21:01
Solar Array Paddle Deploy 14 Sept 03:31:01
3-Axes Control 14 Sept 03:36:01
HGA Deploy 14 Sept 07:09:01
Communication Link Establishment 14 Sept 08:26:01
Injection Error Correction Manueuver 14 Sept 20:11:01
Adjustment Maneuver of Revolution Period 19 Sept 00:46:01
LOI Conditions Adjusting Maneuver 30 Sept 18:56:01
Lunar Polar Orbit Insertion (LOI) 3 Oct 21:01:01
Relay Sat Release 9 Oct 00:46:01
VRAD Sat Release 14 Oct 05:37:01
Observation Phase 21 Oct 10:27:01

[SpaceListener]

Thanks Nop for good detail.

I see that Kaguya will travel slower to Moon than Apollo. This is for the cheapest travel to Moon without has to much acceleration and breaking. Anyway, the time will fly fast.

[lyford]

thanks nop and subaru for the inside scoop -
and godspeed, princess!

[punkboi]

Will Kaguya arrive at Moon within 3 days? Haven't found the Kaguya's mission timing.

Kaguya will take around 19 days to reach the Moon, 37 days till it settles into its final, 100 km high orbit.

[punkboi]

HIGH GAIN ANTENNA DEPLOYMENT (In-flight image taken of HGA!)

http://www.jaxa.jp/press/2007/09/20070915_kaguya_e.html

SOLAR PANEL DEPLOYMENT (In-flight image taken of "Paddle"!)

http://www.jaxa.jp/press/2007/09/20070915_kaguya-2_e.html

Attached thumbnail(s)

 

[Guest_Zvezdichko_*]

I see that Kaguya will travel slower to Moon than Apollo. This is for the cheapest travel to Moon without has to much acceleration and breaking. Anyway, the time will fly fast.

I think we are going to a wrong route if we compare Apollo and Kaguya. Yet, managers plan to take "Earthrise photos" and these pictures will be as spectacular as the "Earthrise photo" taken by Apollo 8 astronauts.

[ugordan]

I expect the images (and HDTV movies) of such scenes to be even more spectacular than what was possible in the late 1960s. Of course, this all depends on how compressed, well exposed etc. the imagery will be. I'm looking forward to that.

[Guest_Zvezdichko_*]

Any news on the first manuevre?

[nop]

Any news on the first manuevre?

According to releases (in Japanese, sorry),
http://www.jaxa.jp/countdown/f13/topics/pd..._0030_vc1_j.pdf
http://www.jaxa.jp/countdown/f13/topics/pd..._0227_va1_j.pdf
injection error correction maneuver (delta-Vc1) was successfully executed.
Apogee 232,782km
Perigee 956km
Period 4d23h37m

Next maneuver (Delta-Va1) was scheduled on 8:00am Sept 16 (JST).
We've heard no news about it yet, but no news must be a good news. I hope her success

[punkboi]

Where is Kaguya? "It is in the position of present KAGUYA."

http://www.selene.jaxa.jp/en/communication/position_e.htm

Makes you appreciate JPL's Solar System Simulator a lot more.

[volcanopele]

nop, do you know if Kaguya will acquire approach imagery as it nears the Moon? Would be interesting to see how image products will looks from this spacecraft with science target, not hardware (though those images are pretty cool, don't get me wrong).

[nop]

nop, do you know if Kaguya will acquire approach imagery as it nears the Moon? Would be interesting to see how image products will looks from this spacecraft with science target, not hardware (though those images are pretty cool, don't get me wrong).

Sorry, volcanopele, I have no information about it. But I'm sure that JAXA will release some moon images on the way, as past spacecrafts (Hiten, Nozomi and Hayabusa) have provided us a lot of images when approaching the moon, the earth and the asteroid.
Stay tuned for further updates.


FYI, the maneuver Delta-Va1 was successfully executed yesterday and now Kaguya is fine.

[Phil Stooke]

Do we have any information about end of mission scenarios? At least the main spacecraft, and eventually the subsatellites, should impact as the orbits evolve and are not maintained. The subsatellites are probably not controllable to target an impact as SMART-1 was targeted, but the main spacecraft could be controlled.

I only live for points on a map.

Phil

[ugordan]

I only live for points on a map.

That's good, you should put that in your sig.

[PhilHorzempa]

We are now about 5 days away from LOI for Kaguya. I want to note
that we are in the last few days of an historic period - a time when
there are no active man-made devices operating on, or near, the Moon.
Once Kaguya enters lunar orbit, I believe that we will be starting an era
when there will ALWAYS be a functioning representative of mankind at
the Moon, either manned or unmanned. We are about to enter a new epoch,
one in which mankind has a permanent presence at the Moon. Unless something
drastic occurs, I foresee no gaps in this lunar presence for the next several
centuries, perhaps for the next several millenia.

It all starts in a few days.

Another Phil

[nprev]

...terrific sentiment. I hope it's true.

[SpaceListener]

Would like to know about how fast will Kaguya be approaching to the Moon at the LOI point. How long will the engines be firing during the orbit injection?

[jabe]

We are about to enter a new epoch, one in which mankind has a permanent presence at the Moon.

What i find amazing is that this can be said for Mars as well, and that started quietly 10 years ago!! I never thought that Surveyor back in '96 would be the start of a continous presence at Mars. If we don't have a rover/satellite/weather station/lander/ etc on Mars running at any one time or another I'd be dissappointed. It is a remarkable time. I teach high school physics and just before the first ISS crew went up I mentioned to my classes that this could be the last time that humans are NOT up in space. I don't think they appreciated what that could mean for them..

I hope that with the Moon being a more "realistic" target, it will get the general public more intrigued and realize that times are changing..how much so we will see... As well This doesn't take into account private space tourism.. Virgin galatic, bigelow etc..

Can't wait for the HD pics to come down of earth rise
Go SELENE!!!
jb

[Phil Stooke]

http://www.jaxa.jp/countdown/f13/index_e.html

Orbit adjustment on the second orbit.

Phil

[cndwrld]

Pronouncing it

I was at the IAC conference in Hyderabad, India last week. They had good presentations on Kaguya, and I'm really looking forward to it.

I learned that I was pronouncing it wrong. We were told by a JAXA person that it is pronounced KA-gu-ya, not ka-GU-ya.

Apparently, ka-GU-ya means 'furniture store.'

There's a funny joke in there somewhere.

[SkyeLab]

Quote:
"Apparently, ka-GU-ya means 'furniture store.'

There's a funny joke in there somewhere."


Because it will be a treat for all us arm-chair space scientists?..........

or

Sofa so good for Japanese Lunar probe?

Hmmm, nope your wrong, there is not a funny joke in there somewhere

Brian

[nop]

Kaguya is carrying a high-definition TV camera as her big furniture and now she have sent a nice picture to us.

KAGUYA (SELENE) Successful Image Taking by the High Definition Television (HDTV)
http://www.jaxa.jp/topics/2007/10_e.html
http://www.jaxa.jp/press/2007/10/20071001_kaguya_j.html (in Japanese)

Delta-Vp2 was successful and now Kaguya is on the Moon transfer orbit.
The picture was taken on September 29, 110,000 km away from the Earth - the most distant HDTV image ever
You can see the South America.

The larger image is here. Enjoy!
http://www.jaxa.jp/press/2007/10/img/20071001_kaguya.jpg

[djellison]

Thanks for the heads up on that - great stuff!

Doug

[ustrax]

Wow! That looks so promising!

[ugordan]

Is that a colorized image or an actual color one? Looks like color, but South America is too invariably blue?

[dvandorn]

It's early spring in South America. There's a lot of moisture in the air over the entire continent. That, combined with the rather extreme slant angle through which we're looking at the ground in this image (putting a lot of air between the viewpoint and the ground) means that yes, it likely is a true-color view.

-the other Doug

[remcook]

I have no idea about the specs, but maybe the color filters are not ideal for "real" color pictures and are maximised to bring out color differences on the moon? Anyone know?

[punkboi]

Awesome photo, nop... Can't wait to see HDTV images and actual video footage of the Moon when Kaguya begins official science operations. Obviously.

[ugordan]

After taking a look at the channels, it is probably true this is a RGB image, but the green and especially the blue channel were overexposed, leading to the unnaturally (?) blue appearance. Here's an attempt at producing a more typical Earth appearance:

[SpaceListener]

According to JAXA report is that Kaguya is now heading toward the Moon. The LOI would be this Thursday October 4. Important day. Later, the relay satellite will be separated on Oct 9, VRAD by Oct 12 and finally Kaguya will be in Lunar Orbit by October 19.

[punkboi]

I presume they mean October 4, Japan Time (as in the LOI is still on October 3, 2:01 pm Pacific Daylight Time)?

BTW, they updated the "Position of KAGUYA" page:

http://www.selene.jaxa.jp/en/communication/position_e.htm

Nice little image there. JPL needs to have that kind of animation instead of the Solar System Simulator.

[nop]

Kaguya has a monitoring camera for cheking the solar array paddle deployment. This camera happened to capture another Earth image.
You can see the Earth through a small clearance between the body and the paddle.
http://www.selene.jaxa.jp/ja/communication...formation_j.htm (Sorry, in Japanese)
http://www.selene.jaxa.jp/image/communicat...071002_01_s.jpg

[nop]

And now the movie has been released.
http://jda.jaxa.jp/jda/v4_e.php?v_id=0496f...p;category=4064
The change of the image is extremely slight and slow. Be patient

[centsworth_II]

The change of the image is extremely slight and slow.

Movement can best be seen by watching features disappear into (I mean -- appear out of) the terminator.

This post has been edited by centsworth_II: Oct 2 2007, 04:10 PM

[ugordan]

Earth's rotation dictates features should be appearing, not disappearing at the western terminator.

The QT version doesn't work for me and it's the only one that would allow scrolling back and forth in the movie, without rebuffering. From what I can see in the WMV, most of the "moving" is KAGUYA moving farther from Earth with only a hint of rotation. The pointing is remarkably steady, though. I almost wish there was that "Apollo-like" human hand factor to show it's actual footage, not CGI renderings.

[centsworth_II]

Earth's rotation dictates features should be appearing, not disappearing at the western terminator.

OOPS!!!

On review I'm happy to point out that this is indeed the case.

[elakdawalla]

Yeah, QT doesn't work for me either. I wish they had posted these in some downloadable format that I could play with

That pic of the solar paddle that happened to catch Earth in it is pretty neat! nop, could you perhaps help out with translation of that page? Here is what the Google translator produces, which isn't bad; only the last sentence is unintelligible:

It was recognized that the earth has taken in the monitor camera for solar paddle development verification. It is the unusual picture where the earth is visible from the interval of the paddle.
Because the picture is not photographing with HDTV, is not clear, but the position of the satellite and the earth timing it could photograph it is the unusual shot well. In addition, you think that you can be understood the distance of the satellite and the earth.

The day when more and more it is thrown to the month track separated from the orbit around the earth, the truth approached the [gu] and, closely.

It would appear that Google's attempt at transliteration of "Kaguya" is "the [gu] and," which is not as cute as "It is quick the [bu]," its famous transliteration of "Hayabusa."

--Emily

[nop]

nop, could you perhaps help out with translation of that page?

Ok Emily, here is my rough translation. Sorry for my poor English. I think Google translation is not so bad, except for the last sentence.

--

We found that the earth was captured by the monitor camera for checking the solar paddle deployment.
It is a rare picture where the earth is seen between the interval of the paddle.
The image is not clear because it was not not taken by the HDTV, but a rare shot in which the configuration of the satellite and the earth was captured in good timing. Also you can realize the distance between the satellite and the earth.
Now Kaguya has left the earth orbit, and the long-waited day for injection into the lunar orbit is forthcoming.

--

This animation showing a diff during the movie was originally posted by anonymous on a Japanese BBS

[nprev]

Cool cool cool, nop!!! Been much more impressed with Kaguya so far than with many other missions...sweet bird, great outreach!

[punkboi]

Kaguya should be in lunar orbit about 13 hours after this posting...

[djellison]

Whaddayaknow... it IS round.

[elakdawalla]

Thank you very much for your posts and translations, nop! You are really a great help in spreading news from Japan!

--Emily

[punkboi]

Whaddayaknow... it IS round.

JAXA is deceiving us, djellison... They refuse to release REAL images taken by Kaguya that shows pristine waterfalls streaming off all sides of Earth's cube-shaped body...

[Norm Hartnett]

JAXA is deceiving us, djellison... They refuse to release REAL images taken by Kaguya that shows pristine waterfalls streaming off all sides of Earth's cube-shaped body...

Typical western nonsense! As can clearly be seen in these JAXA photos the Earth has a disk shaped body and the pristine waterfalls are falling away from the spacecraft and not visible since the craft is going to the moon.

[punkboi]

Typical western nonsense! As can clearly be seen in these JAXA photos the Earth has a disk shaped body and the pristine waterfalls are falling away from the spacecraft and not visible since the craft is going to the moon.

How could I have been so blind???

So we won't know how the LOI went till 9:00 AM, JST on October 5...which would be 5:00 PM, PDT tomorrow.

http://www.jaxa.jp/press/2007/10/20071004_kaguya_e.html

[Phil Stooke]

"At 5:55 a.m. on Thursday, a small engine was fired to change the probe's direction and speed and send it into an elliptical orbit around the moon's north and south poles. JAXA officials said the firing of the engine went well."

http://mdn.mainichi.jp/national/news/20071...0na036000c.html

Phil

[SpaceListener]

At the beginning, JAXA says that Kaguya is mainly as an experimental spacecraft to prove new technologies.. Thus, I presume that this is one of the low-profile public relations' reasons since this kind of mission has high risk of success. Hope, that all new technologies would run fine after many past setback lessons.

[jabe]

looks like they were successful..see spaceflightnow.com article

edit:lets hope jaxa has an official update soon!!

[Norm Hartnett]

At the beginning, JAXA says that Kaguya is mainly as an experimental spacecraft to prove new technologies.. Thus, I presume that this is one of the low-profile public relations' reasons since this kind of mission has high risk of success. Hope, that all new technologies would run fine after many past setback lessons.

I am not sure that Kaguya can be characterized as an "experimental spacecraft to prove new technologies", except as all spacecraft are experimental. At 2 tons and half a billion dollars, carrying 15 cutting edge planetary exploration instruments, this craft is the equal of any flown to any planet. JAXA has stated that it is "the most sophisticated lunar exploration mission in the post-Apollo Era." and "the largest lunar mission since the Apollo program". This mission could be the crown jewel of Japan's planetary exploration efforts for some time to come.

[SpaceListener]

I am not sure that Kaguya can be characterized as an "experimental spacecraft to prove new technologies", except as all spacecraft are experimental.

What I was saying comes from the extract: Kaguya's mission profile

The key technologies, such as the lunar orbit insertion and attitude / orbit control of the Orbiter are verified for future lunar exploration.

More details about Kaguya:
Kaguya (Selene) Home Web
Institute of Space and Astronautical Science (Kaguya)

I agree that the Kaguya is an impressive 3 ton spacecraft along with 15 scientific instruments.

[jabe]

press release is up.

[nop]

I am pleased to share the success of LOI with you all

At the beginning, JAXA says that Kaguya is mainly as an experimental spacecraft to prove new technologies..

Kaguya is a scientific mission rather than technological one, but of course it includes lots of experimental elements for new technologies.

FYI, Japan once had an experimental lunar probe, Hiten (MUSES-A), launched in 1990 to prove new technologies. The mission included LOI, successive swing-by navigation, aero-breaking by earth atmosphere, daughter satellite deployment, orbit determination using optical navigation, observation of space dusts around Lagrange points, and so on. I think Kaguya's LOI was supported by techniques acquired in Hiten mission.
http://en.wikipedia.org/wiki/Hiten
http://www.isas.ac.jp/j/isasnews/backnumbe...ISASnews154.pdf (mainly in Japanese, but including English articles and many figures)

We've had two unfortunate experiences in deploying of daughter satellites, Hagoromo from Hiten and MINERVA from Hayabusa But I hope we'll get "the third time lucky" in upcoming deployment of VRAD and relay satellites

[Norm Hartnett]

I am pleased to share the success of LOI with you all

Hoorah!

Now you're rolling!

[Guest_Zvezdichko_*]

I wonder when the first images will be published

[SpaceListener]

A new update from Kaguya. It has already performed the 3rd LOI.
The First LOI:
Injected orbit
Apogee altitude 11,741 km
Perigee altitude 101 km
Period 16 hours 42 minutes

The second LOI:
Apogee altitude 5,694 km
Perigee altitude 108 km
Period 7 hours 53 minutes

The third LOI: has already conducted. There are still three more.

More details KAGUYA (SELENE) Lunar Orbit Adjustment Maneuver (LOIx)

Just a curiosity, how does the spacecraft able to lower the Apogee?
Trying to understand it, it is done by firing the rocket when the spacecraft is reaching the apogee so that the next loop will go slower and thus reducing its next apogee altitude and continues until reaching the desired altitude?

[jabe]

Just a curiosity, how does the spacecraft able to lower the Apogee?
Trying to understand it, it is done by firing the rocket when the spacecraft is reaching the apogee so that the next loop will go slower and thus reducing its next apogee altitude and continues until reaching the desired altitude?

Simple Really,
The simplest way to raise or lower the perigee or apogee is to do a rocket firing at opposite position you want to change.
ie. to lower apogee you decrease speed at perigee. or to raise apogee you increase speed when at perigee. etc...
so the burn doesn't change the current position..it affects the opposite side of the orbit.
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 )
cheers
jb

[Phil Stooke]

The Relay satellite "Rstar" will be released tomorrow.

Phil

[nop]

Rstar was successfully separated.
http://www.jaxa.jp/press/2007/10/20071009_kaguya_e.html

I wonder when the first images will be published

I think data will be released after checkout of equipment. See translation of the press conference in LOI.
http://jspace.misshie.jp/index.php?LbyD%2F20071005

[SkyeLab]

Nice update and a couple of spacecraft moonshots:

http://www.jaxa.jp/press/2007/10/20071009_kaguya_e.html#at01

http://www.jaxa.jp/press/2007/10/img/20071009_kaguya_05l.jpg

http://www.jaxa.jp/press/2007/10/img/20071009_kaguya_07l.jpg


Enjoy........

Brian

[djellison]

All credit to JAXA - you guys know how to make this cool...

cover it in cameras

Doug

[rlorenz]

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.

[nop]

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)

[ugordan]

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

[kenny]

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.

[SpaceListener]

KAGUYA (SELENE) Lunar Orbit Adjustment Maneuver (LOI4)

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.

[Phil Stooke]

VRAD (Vstar) separation coming up...


http://www.jaxa.jp/countdown/f13/topics/pd...830_vstar_e.pdf



Phil

[kenny]

.... 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

[Phil Stooke]

Getting there...

http://www.jaxa.jp/countdown/f13/topics/pd...925_loi56_e.pdf

Now for the images...

Phil

[Phil Stooke]

Here's the latest - images from the monitoring camera in low orbit.


Phil

http://www.jaxa.jp/press/2007/10/20071021_kaguya.pdf