Indian Space Program: News & Discussion - Sept 2016

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Amber G.
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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Amber G. » 02 Dec 2018 03:43

Ashokk wrote:A minesweeper in the sky that assists farming too
“Hyperspectral cameras with near infrared and shortwave infrared capability can penetrate through soil for up to 5cm, depending on the soil type[/color]. It is, however, not as good as a radar that can penetrate deeper by sending wave energy,” said Prof Uday K Khankhoje, department of electrical engineering, IIT Madras.

Absolutely untrue, Prof peddling La-houri jinn science !
.

Sorry but it is absolutely silly to suggest that those claim are some how " untrue" or "jinn science".

Far from being jinn science these are routine, and real... even as far back as a decade or so I know people who worked in those fields. Infrared technology (with assisted MWIR (Mid-wave Infrared), Laser-illuminated-near Infrared Images, Hyperspectral Anomaly Detection etc) is used for soil typing and yes mine detection.

It is not really a secret that Mine detection, an research area for many of Indian scientist too. Just to name a few methods - advances in Metal detectors electromagnetic induction (EMI), ground penetrating radar (GPR), thermal neutron activation (TNA), quadrapole resonance (QR) and acoustic sensors are just a few other methods along with the techniques quoted by Prof Khankhoje. As one can see Hyperspectral anomaly detection could be used from a airplane or a satellite.

I can put some references here but simple google scholar search for this topic, or query to any reputable scientist in the field can provide material for those who are interested.

It so happens that I got a very exciting news from one of colleague in related field, I have posted that here

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby prasannasimha » 02 Dec 2018 12:23

Haridas wrote:
Ashokk wrote:A minesweeper in the sky that assists farming too
“Hyperspectral cameras with near infrared and shortwave infrared capability can penetrate through soil for up to 5cm, depending on the soil type[/color]. It is, however, not as good as a radar that can penetrate deeper by sending wave energy,” said Prof Uday K Khankhoje, department of electrical engineering, IIT Madras.

Absolutely untrue, Prof peddling La-houri jinn science !
The HysIS camera will work on a visible and near infrared band with a wavelength between 400 and 1400 nanometres (nm) and shortwave-infrared falling roughly between 1,400 and 3,000 nm.

Isro officials said the imager was first tried on board the IMS-1 experimental satellite in 2008. Another hyperspectral camera was sent on Chandrayaan-1 to map lunar mineral resources.

At the heart of the satellite is the detector array chip designed by Space Applications Centre, Ahmedabad and made by Semi-Conductor Laboratory,

Chandigarh. The chip can read 1,000 x 66 pixels. Only a few countries including the US and China have incorporated this technology into their satellites


Many decades ago I was involved selling eqpt to SSPL Delhi (solid state physics lab) to make the optical sensor array for EOS, hyperspectral was an interesting idea being discussed.

Sorry Haridas. Its true. Hyperspectral imagimg has been uses for this previoysly and for mine detection and soil data

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Singha » 02 Dec 2018 12:35

During zero dark thirty there were claims of a drone up there relaying video back to potus situation room ( famous pic )

And a ghawk or rivet joint also up there with a hypspectral imager able to look inside buildings !! Dont know if true or payops

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Indranil » 02 Dec 2018 20:40


disha
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Re: Indian Space Program: News & Discussion - Sept 2016

Postby disha » 03 Dec 2018 08:49

^must watch video

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby naruto » 03 Dec 2018 14:08

Thanks Amber G and prasannasimha ji, your explanation helps.

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby jaysimha » 03 Dec 2018 17:47

Kudos to Solid Propellent Space Booster Plant, Satish Dhawan Space center SHAR, ISRO which is primarily responsible for the production of Solid Motors. They are in the process of 1000th casting.

http://www.shar.gov.in/sdscshar/index.jsp

http://www.shar.gov.in/sdscshar/downloads/SPROB0001.pdf

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby jaysimha » 03 Dec 2018 18:22

Image
Dec 02, 2018
HYsIS First day Image
The 1st Day image from the Hyperspectral Imaging Satellite HYSIS, was acquired at NRSC Hyderabad on 02 December 2018, covering parts of Lakhpat in Gujarat. The sample color composite image represents VNIR spectral bands.

https://www.isro.gov.in/update/02-dec-2 ... -day-image

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Haridas » 03 Dec 2018 22:10

prasannasimha wrote:Sorry Haridas. Its true. Hyperspectral imagimg has been uses for this previoysly and for mine detection and soil data

Kindly tell me which EM wave freq band ( wavelenghth in said hypetspectral camera) can seep through 1 mm of overlaying solid? None ! So where will the camera get its photon ?

Mine detection is based on detecting gradient composition disturbence contrasted against neighbouring pixle. Not because it can see below the suface solid matter.

Only active Radar principle, allows sensing below top solid surface; not possible with passive sensors.

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Amber G. » 03 Dec 2018 23:21

prasannasimha wrote:Sorry Haridas. Its true. Hyperspectral imagimg has been uses for this previoysly and for mine detection and soil data

Kindly tell me which EM wave freq band ( wavelenghth in said hypetspectral camera) can seep through 1 mm of overlaying solid? None ! So where will the camera get its photon ?

Mine detection is based on detecting gradient composition disturbence contrasted against neighbouring pixle. Not because it can see below the suface solid matter.

Only active Radar principle, allows sensing below top solid surface; not possible with passive sensors.

/sigh/
If there is a genuine interest, and one wants to find details (including "frequency band of said photon") one can query Prof Khankhoje, or ask ANY expert (who may be willing) in the field -- or just do a Google knowledge search. All kind of technical details will be there. (Hint: One could also google some of the key words like "Hyperspectral Anomaly Detection" or "MWIR" or "Infrared" and "soil" and "mine detection" as I used in the previous post and that will also help to find articles.)
I just tried that and found scores of articles spanning decades like the following:
Airborne Detection of Land Mines Using Mid-wave Infrared (MWIR) ....
...Hyperspectral Anomaly Detection Method
by a few scientist from US Army's REDCOM - Night=vision and electronics sensor directorate)

/sigh/

This might not be enough to answers all the question but there are many such articles ..Hope this helps.

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Neela » 04 Dec 2018 03:41

The imaging chip is such a critical IP .
And SAC has developed this in-house.

Indian industry should be lining up for this chip.




Image

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Neela » 04 Dec 2018 03:44

Image

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Haridas » 04 Dec 2018 13:43

Ashokk wrote:A minesweeper in the sky that assists farming too
“Hyperspectral cameras with near infrared and shortwave infrared capability can penetrate through soil for up to 5cm, depending on the soil type. It is, however, not as good as a radar that can penetrate deeper by sending wave energy,” said Prof Uday K Khankhoje, department of electrical engineering, IIT Madras.

Please show me one article where the highlighted quoted statement of honerable Prof is corraborated ! Prof is saying Hyperspectral camera can penetrate thought soil upto 5 cm. That is baloney !

Otoh hyperspectral anomaly could be caused by someone digging 1 foot for mine or digging 6 ft from grave or 10m for water well. Doesn't mean hyperspectral camera can see that deep. Only that material pulled out from that deep in earth has material composition that emit a different spectral signature compared to adjescent area. V v different from peeping under surface with superman X ray vision. Lol.

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Vips » 05 Dec 2018 02:55

GSAT-11 launched successfully by Arianspace.

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Amber G. » 05 Dec 2018 05:08

^^^ Thanks for posting. Congrats.

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Vamsi31 » 05 Dec 2018 06:19

Noob question: By when will ISRO be able to launch satellites that are as heavy as GSAT -11?

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Singha » 05 Dec 2018 07:13

That will need the future ULV or major changes in gslv

The gslv mk3 matches the ariane4 which is to say 1 level below the superheavy rockets out there

The weight and height and dia may not change much

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby SaiK » 05 Dec 2018 09:10

https://youtu.be/

Go all the way forward

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Vamsi31 » 05 Dec 2018 10:38

Thanks for the answer. Yes, I think the semi cryo stage will help too. Hopefully, the day India is completely self reliant in launching any type of satellite is not far away.

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Vips » 05 Dec 2018 17:59

Vamsi31 wrote:Noob question: By when will ISRO be able to launch satellites that are as heavy as GSAT -11?


The Semi Cryo engine will increase ISRO capacity to launch satellites in the 6 ton class. Hopefully in the next 3 years.The first semi cryo engine is supposed to be out in 2020.

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Indranil » 05 Dec 2018 21:54

At current rate, I would be happy to see Gslv Mk3 with SCE200 by 2023.

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby prasannasimha » 05 Dec 2018 23:35

^ The test stand is nearly completed so we should not despair. One thing is HSP is a different program. In ISRO many teams are independent and concurrent. Also HSP has a totalky different budget so will not eat into existing projects
If anything it will accelerate needed technology for uprating GSLVMk3

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Haridas » 06 Dec 2018 12:54

Vips wrote:
Vamsi31 wrote:Noob question: By when will ISRO be able to launch satellites that are as heavy as GSAT -11?


The Semi Cryo engine will increase ISRO capacity to launch satellites in the 6 ton class. Hopefully in the next 3 years.The first semi cryo engine is supposed to be out in 2020.

Global market for Heavy satellites launch is saturated. So market opportunities must match
Investment options.

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Singha » 06 Dec 2018 13:42

mostly the very large telecom satellites and strategic payloads like space telescopes used for IMINT need the weight and form factor provided by the falcon9H and ariane5. rest of it like military comsats, gagan, IRS-mki will be smaller and mix of PSLV and mk3 can easily handle. actually if you provide a large payload fairing to accomodate a 15t bulk sat, we can cover the IMINT because the orbit needed is only around 250km for such sats. its the heavy telecom sat to GSO where further mk3++ is needed.

not many know the hubble space telescope in its original incarnation is inside the KH11-12 spy sats - but looking down on earth
they have just started a new series now to replace the 11-mki. they take video and transmit from around 250km orbit , people can watch such video or get photos printed from it. a constellation is kept to avoid having to change orbits and burn fuel too much. they use polar orbits and elliptical shape to spend more time over countries of interest.

the other use case is manned space capsules into LEO and ISS type space station modules again into LEO. even without semi cryo the current mk3 can do this.

so the glass is 95% full or 5% empty

a PSLV replacement , more efficient, cheaper and 2 stage to orbit could be worked on? and on Mil side a Shourya and PAD ASAT combo?

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby mody » 06 Dec 2018 14:49

The SC-160 or SC-200 first stage, with the SCE-200 engine, will replace the L110 stage of the MK3. This will increase the capacity to 5.5 or max 6 tons. Hopefully this will be ready by 2022-23. Then India will be fully self reliant for all satellite launches.

The ULV when it comes will be able to take the max launch weight close to 10 tons. The plan calls for a different solid boosters for different weight requirements. Maybe a S250 booster will also get developed.

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Mollick.R » 06 Dec 2018 18:32

India’s first private satellite launched
More such initiatives are required and it will definitely lead to more participation by private industry, academia...............


NEW DELHI: At the stroke of midnight on Monday, Elon Musk-led US space agency Space X launched India’s first privately built satellite ExseedSAT 1 along with 63 other satellites from 17 countries. After being repeatedly postponed for 10 days due to technical and weather reasons, Space X’s Falcon 9 rocket took off at 12.10 am on Tuesday from the Vandenberg air force base in California. Over 43 minutes after the launch, Falcon 9 placed ExceedSat-1 into the polar orbit.

The mini communication satellite weighing just a kg with double the size of a Rubik’s cube (10 cm x 10 cm x 10 cm) is made up of aluminium alloy. The satellite, which is the brainchild of a Mumbai-based startup Exseed Space, looks to serve the amateur radio community. ExseedSAT 1 was built at a cost of Rs 2 crore. The satellite with a lifespan of five years will allow people to receive signals on 145.9 Mhz frequency with the help of a TV tuner. Built in just 18 months, ExseedSAT 1 has paved the way for private-funded space missions.


https://timesofindia.indiatimes.com/india/space-x-launches-indias-first-privately-built-satellite-exceedsat-1/articleshowprint/66937238.cms

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Mollick.R » 06 Dec 2018 18:36

Another few links with some more interesting details

The ExseedSat-1, built with the contributions of several ham operators and with the help of small Indian firms, is expected to play a major role during natural disasters as it facilitates effective two-way communication through a simple hand-held walkie-talkie with a beam antenna.


The startup was founded by Ashhar Farhan and Kris Nair. The startup claims that it is also part of the private consortium who won the historic AIT bid last year to build large satellites for the Indian government.


"ExseedSat-1 carried an amateur radio payload. Licensed radio amateurs around the world will be able to access, receive and talk through it using a simple hand-held walkie-talkie with beam antenna", Kris Nair, one of the founders said.
Exseed Space is working towards setting up India's first contract satellite manufacturing facility. Once operational, the facility will cater to the growing global demands of manufacturing CubeSats, NanoSats, and MicroSats (1U/2U/3U/6U). Platforms the start-up builds are based on units of 10cm by 10cm by 10cm CubeSats. The power output is selectable between 1 watt and 0.5 watts. The purpose of the mission is to interest student outreach. Depending on the life of the battery, the satellite may provide service for two years and then the satellite would de-orbit naturally.


Sputnik News Link

https://sputniknews.com/asia/201812041070378524-india-first-private-satellite-launched/

CNBC TV18 Link

https://www.cnbctv18.com/economy/exseedsat-1-becomes-indias-first-private-satellite-in-space-1600041.htm

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Haridas » 06 Dec 2018 21:24

Singha wrote:mostly the very large telecom satellites and strategic payloads like space telescopes used for IMINT need the weight and form factor provided by the falcon9H and ariane5. rest of it like military comsats, gagan, IRS-mki will be smaller and mix of PSLV and mk3 can easily handle. actually if you provide a large payload fairing to accomodate a 15t bulk sat, we can cover the IMINT because the orbit needed is only around 250km for such sats. its the heavy telecom sat to GSO where further mk3++ is needed.

:idea: :twisted:

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Haridas » 06 Dec 2018 21:35

mody wrote:The SC-160 or SC-200 first stage, with the SCE-200 engine, will replace the L110 stage of the MK3. This will increase the capacity to 5.5 or max 6 tons. Hopefully this will be ready by 2022-23. Then India will be fully self reliant for all satellite launches.

The ULV when it comes will be able to take the max launch weight close to 10 tons. The plan calls for a different solid boosters for different weight requirements. Maybe a S250 booster will also get developed.

Could you please take a shot at Indian satellite/transponder mkt demand for next 10 years? To see what can't be serviced by isro & need be sent abroad for launch?

S200 would be great, to push to a maxxed up MK3.
The r&d now should move focus to drastically lower Rupees/kg to SSO / GTO.

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Varoon Shekhar » 06 Dec 2018 23:41

Any update on the GSAT-11? Wouldn't there have been at least one orbit manoeuvre performed from the ground stations in India, by now? Or not necessarily? It has been over 24 hours. Hope everything with the satellite is fine.

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Amber G. » 07 Dec 2018 05:38

^^^From what I saw from the press briefing that the Geosynchronous Transfer Orbit((elliptical ) was as close to perfect as they hoped. Rest of the orbit maneuver(s) takes place in next couple of days which is not really a critical part The satellite will remain in that way for years so no need to hurry. Timing has to right (the time period is about 24 hours so one one misses the opportunity one has to wait 24 hours.. no big deal. Normally for any GSO one does that in a couple of days along with other routine tasks like opening up solar panels, testing etc.


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Re: Indian Space Program: News & Discussion - Sept 2016

Postby prasannasimha » 07 Dec 2018 22:41

wrt imaging and soil penetration please refer
Environmental Soil-Landscape Modeling: Geographic Information Technologies ...
edited by Sabine Grunwald pp 141
where it is described that the penetration is limited to the top centimeters of the soil.

In cardiac surgery we use NIRS (near infra spectroscopy) precisely for the ability for near infrared spectrum to penetrate fro a few cms through intact skull to get sample data from underlying brain tissue so hyperspectral imaging in NIRS spectrum does have limited ability to interrogate substances . Differential heating of soil can also be used for analysis using NIRS. Penetration studies like in milk powder etc and soil have also been done and surface clay analysis etc have been done and all of these are shown to penetrate for a few cms. Here absorption reflectance and scatter variation are also used.
In fact in the brain we use NIRS spectroscopy to get the brain tissue oxygen saturation. Similarly we can use it over the liver kidney muscle and various other tissues (jus tto put it in perspective.
Also see this article
http://www.isprs.org/proceedings/XXXVII ... I-2/01.pdf

where soil moisture etc at varying depths and the reflectance has been correlated .

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby lakshmanM » 07 Dec 2018 23:05

^I Worked on NIR based non-invasive glucose concentration measurement device. Work hit the wall when it turned out that source had to be very bright and the receiver sensitive enough to do anything meaningful. RF-based device was promising but our project guide asked us to switch to biomed-image enhancement.


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Re: Indian Space Program: News & Discussion - Sept 2016

Postby prasannasimha » 07 Dec 2018 23:19

lakshmanM wrote:^I Worked on NIR based non-invasive glucose concentration measurement device. Work hit the wall when it turned out that source had to be very bright and the receiver sensitive enough to do anything meaningful. RF-based device was promising but our project guide asked us to switch to biomed-image enhancement.


Yes it can vary dependant on the reflectance characteristic of the particular material you are studying. Fe and Hemoglobin have higher reflectance. The typical depth of pentration through intact skull for NIRS s[pectroscopy is around 5cms and we use a NIRS sources LED.
In fact glucose has poor reflectance which is why surface sensors for glucose measurement have failed miserably.Glucose sensor watches etc were tried but had too pure accuracy but then we are digressing from the topic.

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Singha » 07 Dec 2018 23:37

the PSLV is like the soyuz/proton - reliable but dated.

we need a new cleansheet PSLV on the lines of Angara, light and small as possible to save on cost. and once Mk3 GSLV stabilizes it will be time to take a leap and got for a new design heavy better than Ariane5 in $/kg

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Amber G. » 08 Dec 2018 01:22

prasannasimha wrote:
lakshmanM wrote:^I Worked on NIR based non-invasive glucose concentration measurement device. Work hit the wall when it turned out that source had to be very bright and the receiver sensitive enough to do anything meaningful. RF-based device was promising but our project guide asked us to switch to biomed-image enhancement.


Yes it can vary dependant on the reflectance characteristic of the particular material you are studying. Fe and Hemoglobin have higher reflectance. The typical depth of pentration through intact skull for NIRS s[pectroscopy is around 5cms and we use a NIRS sources LED.
In fact glucose has poor reflectance which is why surface sensors for glucose measurement have failed miserably.Glucose sensor watches etc were tried but had too pure accuracy but then we are digressing from the topic.


Thanks for these messages. I know a few people in MIT who have worked and are working on this and such other applications. For less difficult (or technically challenging) in medical diagnostics one routinely also uses, say gamma-rays spectrum (Gallium-scan etc).. yes routine but in a sense same principle.

Of course, as said before it is absolutely silly to declare that penetration depth has to be zero for "soil". As I suggested, if one is really interested in answers, one could have queried people like Prof Khankhoje -- or ANY physics literate person who is familiar with electromagnetic wave (or photons) transmission through media. One can also look up any good physics source on the subject. It is really not that complicated, the type of problem one may get in a GRE type exam if you want to do graduate work in physics.

Anyway if you are interested how much "penetration" of EM you have for a particular wave-length (= particular energy of a photon) you can do this -

Find the following values for "soil" from any standard handbook of Physics and Chemistry (or measure it yourself) (Of course you can use 'skin' or other material :))

let ϵ ,μ be the electric and magnetic permeability of "soil" ( look up the value for type of soil you have)
ω = 2pi*(frequency of the photon) = 2*pi* c/(wave -length) of spectrum you are interested in.
σ = Electric conductivity of the "soil")

Then penetration depth k = k(ω)=ω *sqrt(ϵμ/2)*sqrt(√(1+(σϵ/ω))+1) (simple formula - plug in the values)

Now how far into the soil depends on the value of "k" and how good is the your detection system. because for every depth of "k" the intensity of the EM radiation (or number of photons of that particular energy) reduces to about 1/e^2 (= 16%) of the value.
(In other words, you can "see" more (or less) than "k" inside the soil depending on how few (or more) photons you need to detect)

Hope this is helpful in estimating what kind of wavelength you can select for maximum depth..

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Re: Indian Space Program: News & Discussion - Sept 2016

Postby Indranil » 08 Dec 2018 02:09

Singha wrote:the PSLV is like the soyuz/proton - reliable but dated.

we need a new cleansheet PSLV on the lines of Angara, light and small as possible to save on cost. and once Mk3 GSLV stabilizes it will be time to take a leap and got for a new design heavy better than Ariane5 in $/kg

Their focus is not on new launchers. They are busy is building up capability to 24 launches per year using existing launchers.

But once GSLV Mk3 stabilizes, it is easy to retain its core and use different boosters for its first stage, to achieve launchers of various capability.

My dream is to see a 150 ton recoverable TSTO powered by SCE200 and CE20.



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