SMART-1 is approaching its operational orbit. ESA has released some images of the Moon on this page:

http://sci.esa.int/science-e/www/object/in...fobjectid=36358

More images:

http://www.esa.int/export/SPECIALS/SMART-1...JHDO3E4E_1.html

The CCD size seems Clementine-ish. But with less compression and more time to study the moon, the coverage may well be much better.

Is it me or does our Moon seem somewhat boring compared to Jupiter and Saturn's oddballs?

Eric P / MizarKey

I am not sure. Some aspects of it seem really interesting...the volcanic domes for instance. I think a lot of it is the old saying "familiarity breeds contempt." The moon is the world we are most used to (other than the Earth). We have had higher resolution images of half of its surface for decades (and if you could seeing as much detail visually for over two centuries) than we have of most of the surfaces of most outer planet satellites. And of course we didn't have "from space" view of earth until half way through this century. So the moon, viewed from above, is the most familar thing to us. I think as a result of this, we think of it as defining normal or ordinary. Really, I can't think of another world like it.

What kind of resolution can we expect?


Ranger landers?!

"The camera itself has a medium field of view of 5.3 degrees by 5.3 degrees and provides a high-resolution image at 27 metres per pixel from an altitude of 300 kilometres. The image measures 1024 x 1024 pixels. "

Overall I have been unimpressed with the resolution of the SMART-1 images. I know an amateur astronomer who is literally taking higher-resolution images from his backyard with a C8.

No one can take 27m/pixel images from their backyard - not even the Keck facility

Doug

Oops, you're right. What I meant to say was not so much that the actual resolution was higher but just that they look much sharper. This guy processes the heck out of his images and gets resolutions fairly to close to his theoretical maximum. The SMART-1 images just look a bit fuzzy to me.

It may be the use of compression. It has 1024x1024 CCDs, and I have yet to see an image released at that resolution. So it is also possible the releases are degraded, or that these are pre-mapping images that have been binned. Whatever the case, at 27 m/pixel, there should eventually be some spectacular mosaics.

http://sci.esa.int/science-e/www/object/in...fobjectid=36801

"Unfortunately, on starting the calibration program, an anomaly occurred on board. On the night of 28 February the EP engine unexpectedly fired for about 11 hours. The cause was later traced to a recent change in the software and was subsequently corrected.

The consequence of this error is a delay in the completion of the instrument lunar commissioning of a couple of weeks. On 12 March, the ESOC Flight dynamics team commanded the spacecraft to perform an equivalent burn to compensate the unintentional one. By the start of April all the instruments should be tested and calibrated and ready to start collecting valuable science data.
"

Ouch, hopefully this will not shorten the extended mission.

Anyone know where are promised HR images of LEM sites? SMART should have taken them many weeks ago...

They're not going to occur till it's in it's lowest possible orbit - some months away yet

Doug

How can a LEM be seen on an image with resolution of 27 m / pixel ? It's not 27 meters across is it ?

There's something on the ESA website about planned imaging of the sites later, at v.low altitude I believe

I thought the same thing as you at first.

Doug

Yes, I'm referring to a press release which mentioned planned pictures of the "landing" sites (I exagerated sayng "LEM" pictures...), some weeks ago.
I cannot find the article, but if I recall correctly, images should be already on the ground and should be very interesting... why they publish so few informations???

It was a space.com article:

http://www.space.com/missionlaunches/050304_moon_snoop.html

Ah, now i remember. I reread it and the idea is to spot rocket plume disturbance by the lunar module and do it in the same manner as they can do now with MGS (cPROTO: rolling the craft during overpass while keeping the imager on the same target can tripple the resolution in the direction of orbit). I did not know SMART-1 has this (fast and accurate) positioning capabilities though.....

A little side step: What would this cPROTO technique mean for MRO-images by the way ? I read that HiRISE has a resolution of about 50 cm/pixel. Would this mean that rolling procedures (enhancing line sampling time) could make images of 15 cm/pixel ?

Hey, 15cm resolution means to have a military spy-satellite around Mars!
Anyway, Marcel, I think that is not necessary to "fast and accurate positioning capabilities" in order to realize this:
if you use a CCD detector, it should be sufficient to set correct "timing" for row scanning and this would eliminate effect
of spacecraft motion (similar tecnique is used in some automated astronomical telescopes like "spaceguard survey" ones).
Anyway, if they really want to portrait LEM vehicles they should fly SMART very low (I calculated a mere 10Km height in order to
have 1m resolution!).
This is due to relatively wide angle used in the AMIE camera aboard this spacecraft...

IIRC - the Smart1 Camera is a discreet 1024 x 1024 pixels, so you couldnt do the cproto type imaging which can only be done with a push-broom single line type of camera.

Doug

10 km ? Could this be done ? There's no drag, so one could say yes.

Found out myself it can be done: apollo 10 came within 9 km's. I'd say do it !

IIRC, some of the mountains on the moon are 5-6km high, so you have to dodge if you want to go any lower. Otherwise its no problem at all.

Just checked the specs for Amie - and yes - it is a 1024 x 1024 CCD, so the concept of Cproto would not work - the only way to get higher resolution would be to get lower.

MRO could, technically, be commanded to do a motion-compensation technique to get higher than 30cm downrange resolution. How succesfull it would be, I dont know. Frankly - the data output from HiRISE is so enormous - I'm not sure if the supporting electronics would be able to cope, but I'm sure the same was said of MOC before they tried.

Doug

Another problem is that given that MRO won't be circling Mars any slower than MGS, to do CPROTO would result in incredibly short integration times, which might lead to images that are badly underexposed. And I don't know if MRO is stable enough to support such resolution.

Ah haa...

http://www.msss.com/mer_mission/finding_mer/index.html#PROTO

HiRISE will already do it internally



Doug

The other problem with really low lunar orbit might be the MASCONs - the mass concentrations which had unpredictable effects on orbits of the Lunar Orbiters and Apollo. Were those eventually mapped out well enough that we could ensure that an object in very low lunar orbit would be able to maintain a stable orbit?

I don't know how well the MASCONs are mapped, but I don't think that really matters as they essentially make any lunar orbit unstable to some degree. I think if they were to ever lower SMART-1 to this kind of altitude it would be end of mission fairly quickly.

J.

Low lunar orbits can be *very* unstable -- like on the matter of days to weeks. Apollo 15 was inserted into its descent orbit (60 x 9 nmi.) on the second rev after LOI, and roughly 18 hours later the perilune had descended from 50,000 feet to 37,000 feet... and dropping. The 15 crew had to perform a bail-out burn very early on PDI day to increase the perilune before the landing could proceed.

Even the "mid-height" lunar orbits that the Apollo CSMs flew weren't all that stable. The Apollo 16 subsatellite was released from the standard CSM orbit (they canceled a shaping burn designed to put the subsatellite into a more stable, somewhat higher orbit), and it fell ou of orbit after only six weeks.

The only lunar orbits that are stable over a long period of time are those that are propulsively maintained... *smile*...

-the other Doug

New status update for SMART-1:

http://sci.esa.int/science-e/www/object/in...fobjectid=37703

It will exhaust all its xenon next month! So, no more ion-drive...
Also, two new pictures:

Glushko crater:
http://sci.esa.int/science-e/www/object/in...fobjectid=37704

And Hadley rille:
http://sci.esa.int/science-e/www/object/in...fobjectid=37705

Do anyone knows final orbital elements?

Answering by myself.. ..some informations here:
http://sci.esa.int/science-e/www/object/in...fobjectid=36683
It seems that Smart will make an equator/North emisphere high-res coverage...
You will find also many other informations, moon eclipse images and a familiar stuff on page 27 of second pdf document ( !)...

Are there Smart-1 moon images elsewhere besides SMART-1 official images? I count only 7 images of the moon. What's up with that?

Eric P / MizarKey

SMART-1 uses new imaging technique in lunar orbit

http://www.esa.int/SPECIALS/SMART-1/SEMPID8A9HE_0.html

Well...it's a bit of a stretch to call pushbroom imaging a "new" imaging technique. It's a pretty old technique, even in space -- Mars Global Surveyor has been doing it for many years, and more recently so has Odyssey, and even another ESA spacecraft, Mars Express, right?

--Emily

Technically, what they are using is what we call "pushframe" imaging -- they have an area sensor with regions of different colors, and they take an image roughly every band height's advance over the surface. Pushbroom imaging uses a single line array; this is what is used by MOC and MEx.

I won't claim to have been the first person to have ever thought of this, but I independently developed it for an unselected Discovery proposal in 1994, and we first used it in a flight instrument for the MARCI on MCO. THEMIS is the first time it was used in Mars orbit, and the MRO MARCI also uses it, as will the Wide Angle Camera on LRO.

Typical ESA press release.

Emily said (quite correctly):

"Well...it's a bit of a stretch to call pushbroom imaging a "new" imaging technique. "

True - but they did add "never used before in lunar orbit" or words to that effect. Which I presume is true.

Phil

latest update...
update
not sure when pictures get up though

Preliminary impact data including a site - on the far side, but they say it might be changed so they can monitor it.

Phil

Perilune of 0 km

* Date = 2006/08/17 ~11:00 (uncertainty ~ 1 day)
* Radius of perilune = 1738 km
* Radius of apolune = 5096 km
* Inclination = 91.4°
* Right ascension of ascending node = 239.7°
* Argument of perilune = 217.5°
* Sun-moon-perilune angle = 87.0°
* Earth-moon-perilune angle = 134.4°
* Longitude of perilune = 174.4°
* Latitude of perilune = -37.5°
* +X to Earth angle when +Z to velocity at perilune = 105.0°
* Velocity at perilune = 2.051 km/s
* Perilune radius change per orbit -1.888 km/rev

It should be noted that the impact date of 17 August 2006 assumes no further changes are made to the spacecraft orbit. It is possible that this date will change to accomodate specific requests to enable monitoring of the impact from Earth.

I, too, thought that the ESA Press Release was a classic bit of ESA-Speak, but as Phil points out it was - strictly - true. Well, apart from the 'push-frame' vs 'push-broom' question, anyway! I wonder when, if SMART-1 reaches a perilune of 0km in mid 2006, ESA will actually announce EOM? 2007? Perhaps they'll claim a new record for *surface* push-broom operations... ...it's said to be quite dusty down there!

On a less silly note, I'm intrigued by the commencement of this new imaging mode at what is by any standards a late stage of the mission. Reading the ESA PR, it looks to me like push-broom/frame is actually quite hard on the imaging system - am I right in this?

Bob Shaw

Update to the SMART-1 end of mision post: the longitude is ambiguous, but I checked with the phase angle data and it must be 174.4 degrees east, not west.

Phil

SMART-1 approach to lunar polar orbit, November 2004

http://www.svengrahn.pp.se/histind/smart/smartatmoon.html

a new image:

http://sci.esa.int/science-e/www/object/in...fobjectid=38821

Phil

Another new image...

http://www.esa.int/SPECIALS/SMART-1/index.html

They are being released at a breathtaking pace these days - assuming you breathe cautiously. I actually emailed Josset at Space-X to point out that people thought SMART-1 was doing nothing because there were no releases. No reply. But we are getting pictures more frequently.

Phil

Phil:

Breathing cautiously? Breathing bi-monthly, maybe... ...it all leads my cynical little mind to wonder if it's because the rest of the images are simply too poor quality-wise for ESA to admit to!

Bob Shaw

I kind of doubt that. The thing to keep in mind about SMART-1 is that it's really quite a high-altitude lunar orbiter, and its camera's lens is quite small. All its photos were bound to be wide-angle, low-resolution shots that really didn't show us anything we haven't seen before. (It is, after all, an engineering test mission; its science output is optional.) I've always thought that the really interesting data from it will all come from its near-IR and X-ray spectrometers -- the former has never been done from lunar orbit at all, and the latter has never been done from a polar orbit.

When push comes to shove, when the ESA launches something, it usually works.

http://space.com/missionlaunches/060307_smart1_moon.html

Engineers and scientists are now targeting SMART-1 for possible impact on the Moon around September 1-2. The current uncertainty range for the exact time of impact is 15 hours.
At the end of June, SMART-1 is slated to carry out two maneuvers. These will fine-tune the exact time of impact. Those slight thrust firings will lead to the spacecraft flying over the Moon at its lowest point at below186 miles (300 kilometers) in altitude.

In early August, SMART-1 will make an overflight of its eventual impact site, racing over that area at just 75 miles (120 kilometers) height in what’s termed as “rehearsal” mode for the early September run-in with the Moon.
A current orbit simulation of the SMART-1 impact for September 2 is at lunar longitude 44.54 degrees West and 36.22 South in Lacus Excellentiae, 10 degrees south of Mare Humorum. A far more refined target point will come as the event draws closer.

Impact observations would include: Infrared imaging of thermal flash; visible/infrared imaging of ejected clouds; hydrazine flame detection; post-characterization of ejecta; as well as exospheric effects if lunar material is blasted high off the Moon’s surface.
In addition there is also intent to conduct follow up searches for the crater produced by SMART-1’s crash into the Moon via the sensor eyes of future, follow-on lunar orbiters.

I wonder if will give us a Ranger-like sequence...I don't know anything about Smart-1's transmission capabilities, so I don't know if this is even possible. But I sure hope it is!

Oh yes, it will transmit one picture every 2.5 seconds as it descends, for nearly 12 minutes. Trouble is, ESA will then release them at the rate of one picture a month, over a period of about 15 years.

Cheers, ESA!

Bob Shaw

That's a relief! I found Ranger 9 way too traumatic.

Phil