Talk by R Navalgund

Note: I wrote this on my earlier blog hosted as I recovered the text from the WayBack Machine. This post appeared on March 01, 2011. I’m trying to collect here again all my old writings spread on various blogs.

I went to the Tata Institute of Fundamental Research (TIFR) on Monday to hear the National Science Day Public Lecture organised by TIFR and the TIFR Alumni Association. The talk was delivered by Ragunath Navalgund, Director, Space Applications Center, Indian Space Research Organisation (ISRO).

At the welcoming address, the TIFR Director gave us a brief about how the day, February 28 had come to being celebrated as National Science Day. He said it was the day that C V Raman had submitted the manuscript which talked about the Raman Effect for the first time. The discovery of the Effect gave Raman a Nobel Prize and is still one of the most renowned discovery by an Indian scientist. He said further that Raman used to give public talks on science in a manner which was understandable to the general public. This is perhaps one of the first examples of science outreach by an Indian scientist. The day was later adopted by the Government of India to be called National Science Day. At TIFR, the day was celebrated by lectures from prominent alumni members.

R Navalgund then gave the Director a copy of the lunar atlas with pictures from the Chandrayaan-I spacecraft. I was thinking of nicking it!

Navalgund began his talk titled, “Remote Sensing of the Earth and the Moon” by talking about remote sensing in general. He defined it and explained how it was different from “seeing with our eyes”. He explained the difference as being sensing in various wavelengths of the electromagnetic spectrum other than just visible light like our eyes. The results are in the form of data sets which are then converted into images. He explained that remote sensing was done from various platforms – low-Earth orbit and geo-stationary orbits depending on their applications.

He moved on to various types of sensing – active and passive and then explained the various techniques of remote sensing. He showed the push-broom type, the pixel-by-pixel type, the synthetic aperture radar and the hyperspectral imaging.

He talked about how various parts of the electromagnetic spectrum could be studied in individual bands interacted with objects on the ground and how these could help in providing useful information. As an example, he talked about studying leaves with red light and near infra red light to understand if leaves were healthy or mature. This data helped in providing the Government a plausible estimate of the healthy plants in the country well before the harvesting period. Similar studies were done in various spectrum for hydrology, cryosphere, forest cover, atmosphere and oceans to provide similar information. Information involved ground water levels, forest covers, smogs, possible fishing zones, crop health prediction and yield.

He then moved on to the remote sensing of the Moon. He showed the various types of craters and features like the central peaks of craters and impact melts. He also showed pictures from the recently discovered lava tube.

The interesting points though came out in the question and answer session. Answering questions by students from Kendriya Vidyalaya, Navalgund came out with quite a few interesting points that were unknown. Speaking on India’s participation in the International Space Station (ISS), he said that there was an informal agreement on the possibility of India conducting experiments on the ISS. He said that the discussions were currently on in this regard. The experiments, he said, would relate to the study of green house gases. He said Indian institutions would have to provide a proposal for these experiments and some would also come from within ISRO. Answering another question on the Human Spaceflight Programme, he said that all the designs, approvals and paper work was done. The Programme had got an in-principle nod from the Indian cabinet. Discussions were currently on as to how to implement the programme. The two ideas included doing the testing in a single shot or testing the elements individually as done with Space Re-entry Experiment (SRE). He said the programme was in this phase currently. Answering a question I posed, he shocked me by saying that data from the Terrain Mapping Camera (TMC) and Hyper Spectral Imager (HySI) have been made available online. Srinivas found the website for me, it is here. Navalgund explained that the images were released only after 1 year to aid the investigations done by principal investigators who were the primary users of the data. He said that NASA had separately released the data from the Moon Mineralogy Mapper (M3). On Mars, Navalgund said that the plans were currently in drawing board phase and currently, India only had capability to do a flyby or orbiter programme indigenously.

My friend, Srinivas asked the question about why India’s CHACE instrument was not given the credit for the lunar water discovery as much as M3 or even Mini-SAR. Navalgund replied that the instrument did have a short operation span and did find spectrum peaks for water, carbon dioxide and other elements. He said a lot of time was spent on calibrating the data properly. This was a long drawn process which possibly led to the CHACE losing out on the credit for the water discovery.

I also met a member of the newly joined Google Lunar X Prize team, Team Indus at the lecture.

Using Chandrayaan-I to find human habitability sites on the Moon

Note: I wrote this on my earlier blog hosted as I recovered the text from the WayBack Machine. This post appeared on February 24, 2011 as per the time stamp. I’m trying to collect here again all my old writings spread on various blogs.

The current edition of Current Science magazine has the paper by Arya et. all titled, “Detection of potential site for future human habitability on the Moon using Chandrayaan-1 data“. The result itself was reported way back in March, 2010. The paper provides more details and some interesting facets. The paper is based on work done by the Terrain Mapping Camera on board the Chandrayaan-I spacecraft.

The high spatial resolution of the Terrain Mapping Camera and the close 100 km orbit helped scientists build Digital Elevation Models (DEM) to help study the lunar terrain in great detail. This was used to study potential human habitability sites on the Moon. Based on previous studies, they concentrated their efforts on riles and lava tubes on the lunar surface. Study on the Oceanus Procellurum region on the Moon showed that lava tubes were good places for possible human habitability. They found that there was no effect of cosmic rays deeper than 6 meters, no effect of solar particles deeper than 1 meter, no radiation effects and no significant temperature difference was observed with the temperature remaining nearly constant at -20 degrees Celsius. It is also opined that the presence of partial lava tube structure reduces requirement of construction. Scientists also think that the cool temperatures here could make these a candidate for water and ice traps on the lunar surface. Lava tubes also provide a dust free environment.

Lava Tubes are interesting to study for reasons other than human habitability as well. To geologists, it provides a section of the lunar bedrock and top soil that would be difficult to access otherwise. It could also help geologists to study native lunar material which has not been affected by external factors like meteoric impacts, solar particles etc. It could also provide an understanding of the thermal profiles and volcanism on the Moon.

The paper now profiles the area of the Moon under study, Oceanus Procellurum using a picture of the Moon taken by the CARTOSAT-2A spacecraft from Earth orbit!

Using various techniques (explained in the paper) they find that the rough cylindrical tube which comprises the lava tube is 120 meters in diameter and 1.72 km in length. The thickness of the roof is 170 meters hence safe from various considerations discussed above (radiation, cosmic rays etc.). The Hyper Spectral Imager (HySI) was used to do chemical and mineralogical study. It was found that the surface was homogeneously basaltic rich in Iron and Titanium. The homogeneity of  the results was also used to predict that there was no lava flow after the lava tube was formed. To confirm the result, surface ages of the north and south section of the uncollapsed rille was done using the crater counting technique. Using this method ages of the northern section was found to be 3.47 Ga and the southern section was found to be 3.43 Ga. This more or less rules out “differential emplacements of the mare basalts”.

The authors of the paper state that using similar procedures, TMC and HySI data can be used to study different areas on the surface of the Moon.

Three Chandrayaan-I related papers out

Note: I wrote this on my earlier blog hosted as I recovered the text from the WayBack Machine. This post appeared on February 23, 2011 as per the time stamp. I’m trying to collect here again all my old writings spread on various blogs.

Three papers directly related to instruments on-board the Chandrayaan-I spacecraft are out in 2011. Here’s a brief pointer to each.

1. Goldschmidt crater and the Moon’s north polar region: Results from the Moon Mineralogy Mapper (M3); Cheek, Pieters et. all

2. Strong influence of lunar crustal fields on the solar wind flow [full paper – PDF]; Charles Lue et. all

3. Lithological mapping of central part of Mare Moscoviense using Chandrayaan-I Hyperspectral Imager (HySI) data; S Bhattacharya et. all

For the first paper, Cheek et. all, have trained their eyes on the Goldschmidt crater. The comparison of spectroscopic details from Goldschmidt to the Moon Mineralogy Mapper (M3)’s data of the Northern pole and from three different regions provide three different soil types – feldspathic soils with a low-Ca pyroxene component, feldspathic soils and basaltic soils. The content of Goldschmidt is feldspathic and was found to be locally different from the surrounding highlands. They state that the water spectrum is closely associated with the mineralogy of where the spectrum is located. Goldschmidt is said to have higher concentration of water spectrum compared to the local highlands but is similar to the feldspathic soil in the lunar far side.

The second paper by Charles Lue et all is available in full. The SARA payload on Chandrayaan-I had detected the presence of mini-magnetospheres on the surface of the Moon. The paper Lue et. all believes that these magnetospheres affect the upstream solar winds. This affect the rate of solar wind proton hitting the surface of the Moon and also perhaps space weathering in places near the magnetic anomalies. The team uses data from the Solar Wind Monitor (SWIM) on Chandrayaan-I for these studies. Concluding, they say:

Magnetized electrons are deflected by the magnetic field gradient and set up a charge separation (because  protons are non‐magnetized), resulting in an ambipolar  electric field. The related potential repels a fraction of the  protons. Therefore, the deflection can take place not only  over the strongest magnetic anomalies where the protons can  be magnetized, but (although at a lower efficiency) also at  weak, isolated anomalies of ❤ nT at 30 km altitude, with a  width of <100 km. Similar charge separation scenarios have  been discussed in early studies based on Apollo 12 surface  observations [e.g., Neugebauer et al., 1972], and in a recent  review paper by Halekas et al. [2010].

This paper too has some influence on the lunar water formation technique suggested of solar wind implanting protons which are used by the OH ions to form water:

Regardless of the deflection mechanism for protons,  the high solar wind deflection and reflection rates, as ions  and neutral atoms, imply a lower proton implantation rate in  the regolith at magnetic anomalies that may alter the space  weathering compared to the surrounding areas. Moreover, it  might affect the production of OH/H2O in the outermost  layer of the regolith via transfer of solar wind‐implanted  protons to the mineral‐bound oxygen [Pieters et al., 2009].

The paper is available here in full.

The third paper, Bhattacharya et all investigated the central region of the Mare Moscoviense region of the Moon. The paper has identified 5 geological units:

five major compositional units have been identified: highland basin soils, ancient mature mare, highland contaminated mare, buried unit with abundant low-Ca pyroxene (LCP), and youngest mare unit

The paper seems to be aimed as basis of using the Hyper Spectral Imager (HySI) data to delineate major compositional structures on the surface of the Moon and has done so successfully enabling it to be used for the rest of the data sets obtained.

Additions: Hubble Supports Water Discovery

Note: I wrote this on my earlier blog hosted as I recovered the text from the WayBack Machine. This post appeared on February 15, 2011 as per the time stamp. I’m trying to collect here again all my old writings spread on various blogs.

I wrote quite hurriedly about the Hubble Space Telescope providing support to the Chandrayaan-1 discovery of water in the lunar exosphere. I had provided the links to the story to Srinivas and he’s written about in the Times of India [Bangalore, Delhi]. I got a bit worried last night when I saw that the abstract published was presented in the poster session of the meeting of the American Astronomical Society.

With a bit of help from Syed Maqbool Ahmed, PI, CHACE (which made the discovery of water in the lunar exosphere) and Daniel Fischer, I was able to ascertain a few things and I am posting them here for the benefit of everyone concerned.

Daniel informed me that posters are considered “publications” but that a paper in a refereed journal would have greater impact and would be cited more often. It was Syed who finally explained the whole concept to me. The paper in which the result would be published as a paper is expected to happen next month. It is expected to be published in the Astrophysical Journal. One of the persons who presented the poster, Alex Storrs is a co-investigator on the Hubble Space Telescope. Syed explained to me that since they were waiting for the paper to be officially published, they presented it as a poster in the meanwhile.

Trying to find out information about the authors of this poster also took me to a 2009 story in PhysOrg, where Storrs is quoted as saying that initial results did not point any clear evidence for water in the lunar exosphere. It is very interesting that almost a little more than a year later, the same person has confirmed CHACE’s results of water in the lunar exosphere.

Hubble Space Telescope confirms water in lunar atmosphere finding

Note: I wrote this on my earlier blog hosted as I recovered the text from the WayBack Machine. This post appeared on February 13, 2011 as per the time stamp. I’m trying to collect here again all my old writings spread on various blogs.

Tirtha Pratim Das of the Space Physics Lab, VSSC wrote an article in the Voyage Magazine, a magazine written by a few people working in the ISRO labs about the Hubble Space Telescope confirming the presence of water in the lunar exosphere.

The Hubble Space Telescope was making observations of the LCROSS impact last year when it spotted a continuous signature of water vapour emanating from the lunar exosphere. Writing in the Bulletins of the American Astronomical Society, Storrs et. all write an article called “The Impact of the LCROSS Satellite with the Moon as seen by the Hubble Space Telescope“, the authors write:

Images immediately before and after the impact show an enhancement in the scattered light near 300 nm within a minute of the event. Spectra show persistent emission of the OH (1-0) band at 283 nm, which may indicate a permanent lunar exosphere of OH as reported by Sridharan et al (2010), rather than OH produced by photolysis of water liberated by the impact event.

Amidst the hullaboo over the ISRO/DEVAS deal, this is good news for ISRO. Congratulations once again for the CHACE and Chandrayaan-1 teams.

[+ Clarifications]

India goes to the Moon!

This article originally appeared on my blog I recovered the post using Wayback Machine.


Yeah! It is yesterday’s news and you might be wondering what I have been doing for so long when the greatest news in the Indian space programme was breaking. Well, I was busy being Chandrayaan1 on Twitter

This is not connected in any way to ISRO – although I do email them the questions that I get here. I haven’t told that many people what I have been doing either. I have tried my best – please do have a look and comment!

Well, to summarize all the news – India’s first space craft to the Moon has successfully reached lunar orbit and is now circling the moon in a 100 kms circular polar orbit, doing the orbit in an awesome 2 hours.  Two on board instruments – RADOM and TMC have been switched on and are working. TMC is a camera that is taking images of the moon while the RADOM is a radiation sampler.

Tonight at around 10 pm, Chandrayaan 1 will drop the MIP (Moon Impact Probe) onto the surface of the moon. It has flags painted on four sides and will be the FIRST INDIAN OBJECT ON THE MOON! This drop will show that India can drop a probe/lander/rover onto the lunar surface the next time we come to the Moon!

Chandrayaan 1 countdown begins

This article originally appeared on my blog I recovered the post using Wayback Machine.

After what is termed as a “dress rehersal” yesterday night succeededChandrayaan-1’s countdown should have started up today morning. I think what they are referring to as a dress rehersal is going through all the steps of the launch right up to the final step without actually launching the launch vehicle (just a fancy technical name for a rocket with a payload). Things have now moved into their final phase.

Space bloggers like Emily Lakdawalla is claiming the difficulty in getting images of Chandrayaan I online. It might be difficult to see a total lack of images or information after being used to bombarded with information via websites and mailing lists. ISRO doesn’t have a good website or a good mailing list. ISRO’s Chandrayaan I website may have been well designed but it hasn’t been updated for the past 17 months. 

One of the claims that this mission was supposed to do, was to encourage excitement among the younger generation for the space sciences. This was iterated several times by the Prime Minister himself. Looking at the number of people online today, I believe that ISRO should have presented their stuff online in a much more better way than has been  done. For this historic launch too, everything has been left for the media to piece and stitch together. I believe mediapersons were given a grand tour of the launch site at Sriharikota, but nothing significant has come out of it.

There are a few people working though. Times of India’s Srinivas Laxman’s coverage (see related stories for the latest) has been outstanding, though not well timed with the launch. NDTV’s Pallava Bagla, who also co-wrote a book has some excellent coverage and a good dedicated website for India’s Moon Yatra.

In the CitizenSpace efforts to popularize Chandrayaan I launch, my friend, Raghunandan (Planetary Society, India) constant pleas for material on Chandrayaan almost fell on deaf ears. The electronic data that he now has in his hands is, in his words, “quite awesome”. He is now in transit, trying to get an unofficial glimpse of the Chandrayaan I launch. He hasn’t been able to put the content online but will be happy to forward the material to you after the launch. Catch him on his email id – planetarysocietyindia (at) gmail (dot) com. 

I am also planning to carry a series of articles on how students today can benefit from Chandrayaan I’s launch on October 22 in a series of six articles on the SEDS India blog. To sign off, the media is the best place to catch the latest action in the Chandrayaan I launch arena. I’ve tried my best to try and get some of the content online and I accept, failed but I hope the lessons I have learnt enroute will help me in future launches.

People behind Chandrayaan-1

On Chandrayaan I’s coverage on NDTV there are exclusive interviews with the scientists and technicians who have made the various online instruments on board Chandrayaan I.

  1. Dr. Mylswamy Annadurai – He’s the Project Director of Chandrayaan I. There was a small note about him in the Times of India. He said designing Chandrayaan 1 was like writing lyrics for a set tune. He’s also from a district next door to my home town. He’s from near Pollachi, Coimbatore.
  2. J A Kamlakar – an expert on LASERS. His instrument on board Chandrayaan I will help measure height variation on the moon’s surface.
  3. Dr. Manuel Grande – Principal Investigator CIXS ( Chandrayaan I Xray Sepctrometer). Doug Ellison made an animation on this instrument.
  4. Dr. Urs Mall – SIR 2 (Near Infra Red Spectrometer)
  5. Dr. Stas Barabash – SARA

I’m sure that the names indicate to you the international team that has instruments on board the Chandrayaan I. It is a special feeling to have your instruments on board a space craft and to see it fly and I hope every one of you gets an opportunity to have that experience. The last rant doesn’t mean that the technology and people behind Chandrayaan 1 isn’t cool, just that it would be a lot cooler if they shared some of their thoughts with us.

The specialised NDTV page on Chandrayaan is here.

Chandrayaan Video

Note: I wrote this on my earlier blog hosted as I recovered the text from the WayBack Machine. This post appeared on November 21, 2007 as per the timestamp. I’m trying to collect here again all my old writings spread on various blogs.

If you like to know what the latest India’s moon mission is about, you might want to take a look at this video.

Sorry, but embedding the video (this video has been disabled) and a higher resolution one is available here.

Update: Found a longer and more descriptive version which can be embedded here:

A Few Links…

It’s really very funny experience if you want to blog about space. You love the subject. You can talk for hours, given the chance, but to write a good blog post will take you days and days.

Well, all said and done, I have nothing useful to add today. Here are some links –

1. India’s Chandrayaan-I project scheduled for departure on 30 March, 2008. Chandrayaan-II coming up in 2010.
2. The recent testing of SRE and the launch of 3 sats together on the PSLV-C7.
3.India’s best offering in terms of images of the Earth from  space – CARTOSAT-2.