The Indian Space Research Organization reports that their Chandrayaan-1 Moon probe has entered what’s called a Lunar Transfer Orbit (or LTO), a path that will take it to the Moon.
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It has been orbiting the Earth since its launch on October 22. Technically, it still is orbiting the Earth, but this new LTO is a highly elliptical path that takes the probe very close to the Moon. On November 8, Chardrayaan-1 will fire its thrusters again, and that will slow it enough to achieve lunar orbit. From there, it will settle down into a much lower, more circular orbit, and then the fun begins as it maps our nearest neighbor in space. I’m really looking forward to the images and science it will return!
November 5th, 2008 at 9:58 am
I saw the picture first and immediately thought, “Yay! Slingshot!”
November 5th, 2008 at 10:01 am
Am I a horrible human being for wondering who the Indian Space Research Organization calls for tech support? Did they outsource to China perhaps? (Check out Outsourced the movie: http://www.outsourcedthemovie.com/ It’s actually a very touching and charming little film.)
Actually, in all seriousness, WELL DONE! The more people get serious about scientific research, the more excited I am about the prospects for humanity. You all are inspirational.
November 5th, 2008 at 10:07 am
This may sound like a stupid question, but is that the type of path the Apollo astronauts took to the moon? I guess it never occurred to me that is wasn’t a direct route.
November 5th, 2008 at 10:13 am
I second Gnat’s question – I was wondering about that too.
Another question I have: will the probe’s orbit take it over the Apollo missions moon landing sites by any chance?
November 5th, 2008 at 10:19 am
The Apollo flights made the LTO in one long burn from parking orbit, instead of the incremental steps you see here.
November 5th, 2008 at 10:19 am
Gnat,
Apollo used a bit more fuel and did a direct lunar orbit insertion as I recall. Perhaps someone with better Google skills can find a better source than Wikipedia…
November 5th, 2008 at 10:38 am
I couldn’t get a clear reasoning on the ISRO site, but I’m wondering if they are taking this slow transfer orbit approach just as a savings on consumables. As we’ve seen before, it can be a really quick trip to the moon, if you want to put the pedal down.
November 5th, 2008 at 10:41 am
I often wonder about those S-IVB’s used for trans-lunar injection. Where are they?
Here’s a decent wikipedia entry on how to get to the Moon.
http://en.wikipedia.org/wiki/Trans_Lunar_Injection
November 5th, 2008 at 10:42 am
I was wondering… How much information about the mission will be public and how much will be private?
I haven’t followed many non-NASA missions so I’m not sure. Will all the data that Chandrayaan discovers be shared openly with the world with no filtering whatsoever or will we only hear what India decides to release to the public?
November 5th, 2008 at 11:00 am
Go, Chandrayaan-1! I’ve been salivating for nearly 37 years, waiting to start heading back to the moon for real. You can have your nasty ol’ red planet…I want the moon!
November 5th, 2008 at 11:15 am
I’m guessing the looping orbits don’t have anything to do with being more efficient, rather the onboard thruster is low enough on thrust that it couldn’t perform the entire TLI burn at perigee. They had to thus slice up the TLI delta-V into several segments, each centered around perigee which gives you maximum bang-per-err… rupee.
November 5th, 2008 at 1:16 pm
Wow! Do you know how refreshing it is to see a mission launched to the Moon again? Our neighbor is fascinating and we have virtually ignored it because some deam it “boring”. No way! Not only is it not boring, but it’s CLOSE! Arriving at your destination only 17 days after launch??? What a treat in this day and age when the average wait time from launch to data return is measured in YEARS. Go India go!
November 5th, 2008 at 1:43 pm
Remember that LRO is going up early next year (April)!
November 5th, 2008 at 3:10 pm
@ Larian LaQuella
I found an interactive web-site that gives a graphic sequence of major events during the flight of Apollo 11 to the Moon and back to the Earth:
Apollo to the Moon — Steps on the Flightpath
I would have found this sooner, but even geeks have to eat!
November 5th, 2008 at 6:14 pm
Don’cha wish you were riding along? Cool.
November 5th, 2008 at 6:39 pm
Clayton Says: “I often wonder about those S-IVB’s used for trans-lunar injection. Where are they?”
Excellent question. The first few (Apollo 8, 10 and 11) were put on a trajectory to miss the moon and went into a solar orbit more or less the same as the Earth’s. After Apollo 11 left the first seismograph on the surface, the other S-IV B’s were targeted to hit the moon in different areas. Since they were of a known mass traveling at a known speed hitting in a known location, it gave geologists (well, selenologists) a precise “event.” By watching the way the waves propagated, it told them a tremendous amount about the moon’s internal structure.
BTW, the S-IV B’s that are still in solar orbit don’t always stay there. One of them (don’t recall which at the moment) was perturbed back into a very high Earth orbit a couple of years ago where it hung around a while before leaving again.
- Jack
November 5th, 2008 at 6:39 pm
I wonder the same thing. I’ve seen very few (one?) pictures from Chang’e 1, the recent Chinese mission to the moon. I’m curious if India will release more.
November 6th, 2008 at 12:34 am
Hi!
I wonder why they do not send more power to the mission. They would save very much time.
With kind regards!
Okuro Oikawa
November 6th, 2008 at 1:40 am
Jack: The S-IVB that returned to Earth vicinity briefly is from Apollo 12. Wikipedia excerpt:
“The S-IVB was originally intended to be put into a solar orbit by venting the remaining propellant. However, an extra long burn of the ullage motors meant that venting the remaining propellant in the tank of the S-IVB did not give the rocket stage enough energy to escape the Earth-Moon system and instead the stage ended up in a semi-stable orbit around the Earth after passing by the Moon in November 18, 1969. It finally entered into solar orbit 1971, but returned to Earth orbit (briefly) 31 years later. It was discovered by amateur astronomer Bill Yeung and he gave it the temporary designation J002E3 before it was determined to be an artificial object.”
It’s kind of neat they were able to spectroscopically detect titanium-oxide which made up the paint used on the Saturn V and conclude it’s not an asteroid.
November 6th, 2008 at 2:05 am
So, the ISRO was initially going to do this in one shot, but decided to change to five orbital burns in order to make sure they successfully got it into lunar orbit. This method is a lot less risky and since this was their first mission of this type, they decided to play it safe.
The information from this mission will be more public. NASA has two instruments on board, several others are from foreign countries, and NASA is also providing communications assistance. In exchange for this, the information will be shared. India, as well as Britain, Canada, France, Germany, Italy, Japan and South Korea, have signed a lunar science agreement with the US, all part of its plan to go back to the Moon. This is a lot more international than the days of Apollo.
November 6th, 2008 at 3:37 am
Larian LeQuella,
You are indeed being a nasty human being. Good scientific research has no barriers. It just requires a dream, hard work and intelligence. I’m sure my country has enough, if not more of those. It’s a pity that good science requires large amounts of money in today’s world, and we have to direct lots of our money to social causes. I’m sure you would have heard that the entire mission costed about as much as a Large Jet Liner. Let’s all celebrate the achievement both for the county and for science!
November 6th, 2008 at 5:12 am
American Voyager said:
The Apollo missions did this in 3 days, but they first had to heft a helluva lot more propellant into orbit. Hence, in part, the requisite size of the Saturn V. (The rest of the need for such a powerful rocket was the sheer size of the LEM and the CSM – IIRC, a fully-loaded LEM was about 9 tons for Apollos 11, 12, 13 and 14, and about 12 tons for Apollos 15, 16 and 17).
November 6th, 2008 at 10:57 am
I think that the Indians did not attempt a direct moon shot but rather this loopy route because the PSLV booster could not lift more than about 1500 or so kilograms. With this weight limitation, there is only so much fuel you can have on board the satellite. Keep in mind that the PSLV booster was initially meant to put satellites into sun synchronous or low earth orbits.
Now India could have gotten there a lot quicker with the GSLV booster, which is capable of lifting around 2000 kilograms, but the vehicle is not yet as reliable as the PSLV. For one thing it depends on a Russian engine for one stage. For another, at least two of the four launches have had problems with underperformance (the first and the fourth). Additionally the third launch was a total failure, but that could have been due to a manufacturing and not a design defect.
The noteworthy aspect of this mission (assuming it is successful) is not that India orbited a satellite around the moon, but it is that they did it on a very small budget, by repurposing existing and proven rocket components. In a sense, the Indian Space Research Organization is to rocketry as Tata Motors is to inexpensive cars. If they manage to get the larger GSLV booster working reliably and at low cost, they will be in a position to supply both satellites and launch services as some sort of a package deal to interested parties.
November 6th, 2008 at 11:37 am
AJ:
Yeah, like over US$1,500,000,000 on the recent US President Election 2008 campaign!
November 6th, 2008 at 2:01 pm
One little thing to add to Jack’s post above. It is my understanding that Apollo 12′s S-IVb returned to Earth orbit via the Earth-Moon L2 point and left the same way. They also expect it to come back in the next few decades again. Apparently those points, especially L1 & L2, are not only stable, but act as portals.