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by prasannasimha
27 Aug 2019 00:29
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

Not everything in military and space engineering is the latest or most efficient but often most reliable or time tested.For eg the processors for both space missions and military are slower than the fastest chips available(in fact many times slower) but things like radiation hardening etc etc are mo...
by prasannasimha
25 Aug 2019 19:57
Forum: Military Issues & History Forum
Topic: Indian Space Program: News & Discussion - Sept 2016
Replies: 4397
Views: 1072397

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

It was this - Cheaper and lighter: 'Made in Gujarat' spacesuits to be used in Gaganyaan. The countdown to India’s ambitious manned spaceflight mission Gaganyaan has begun and Isro scientists are at breakneck speeds to achieve the mission’s December 2021 deadline. India’s indigenously developed astr...
by prasannasimha
24 Aug 2019 17:14
Forum: Trash Can Archive
Topic: India Border Watch: Security and Operations
Replies: 4479
Views: 848432

Re: India Border Watch: Security and Operations

Nag has been used before as per baba
by prasannasimha
24 Aug 2019 17:10
Forum: Military Issues & History Forum
Topic: Indian Space Program: News & Discussion - Sept 2016
Replies: 4397
Views: 1072397

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

Varoon Shekhar wrote:I remember reading that a spacesuit was already made several years ago. Maybe they want more, or to try a different kind?

Technically it is a flight suit and not a space suit for EVCA.
More than that Russian collaboration is required for various training procedures etc.
by prasannasimha
24 Aug 2019 17:09
Forum: Military Issues & History Forum
Topic: Indian Space Program: News & Discussion - Sept 2016
Replies: 4397
Views: 1072397

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

Tenders for SC120 (from IPRC) continue to flow. This jingo is very happy! If you see the budgetary allocation of semicryo engine there are two budgetary allocations of interest = one is the semicryo itself and the other is for clustering of semicryo engine. Other interesting allocations are for spa...
by prasannasimha
23 Aug 2019 23:25
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

There are Doppler Inertial navigation systems and star sensors that are used for navigation
by prasannasimha
23 Aug 2019 23:20
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

From the calculations that I made (and I may be wrong about it) the Orbiter high resolution camera is 11,25,00,000‬ pixels from my calculation = 21.45 Megapixel camera and resolution of 0,32 meters Terrain mapping camera From ISRO website TMC 2 is a miniature version of the Terrain Mapping Camera us...
by prasannasimha
23 Aug 2019 07:55
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

Orbital inclination changes are typically done at the ascending or descending nodes or at intersection of current and desired orbit
by prasannasimha
23 Aug 2019 07:53
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

Varoon Shekhar wrote:Is that correct, about the recent pictures coming from the Vikram lander? The lander is not described as having an optical camera. It has 3 other type paylods. Do they mean the Orbiter?

The images are from the orbiter
by prasannasimha
23 Aug 2019 07:47
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

Varoon Shekhar wrote:Is that correct, about the recent pictures coming from the Vikram lander? The lander is not described as having an optical camera. It has 3 other type paylods. Do they mean the Orbiter?

No it is from the orbiter
by prasannasimha
22 Aug 2019 23:56
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

To get to the Lunar Transfer Trajectory, Chandrayaan-2 gradually increased the apogee using Oberth Effect via LAM firing at the perigee. I understand that. Now, couple of questions: But once around the orbit of the moon, to decrease the apogee and get to a more circular orbit, does the LAM fire at ...
by prasannasimha
20 Aug 2019 21:49
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

Talked to an actual space engineer and the three body problem and involvement of Lagrangian points are not used except for actual missions to Lagrangian points. The ellipse assumption is enough for modeling for lunar missions
by prasannasimha
20 Aug 2019 21:47
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

Mort Walker wrote:
juvva wrote:114 km x 18072 km -achieved
vs
118 km x 18078 km -planned

WOW !!!!!


Most excellent!!!!

That's a sigma of 4.505 for apogee
by prasannasimha
18 Aug 2019 19:39
Forum: Military Issues & History Forum
Topic: Indian Space Program: News & Discussion - Sept 2016
Replies: 4397
Views: 1072397

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

sivab wrote:SCE-200 is a staged combustion engine.

Yes indeed I was referring to a full(LOX LH2 staged combustion engine that requires full engine firing. . In a semicryo you can hot test certain portions for eg till preburner.
by prasannasimha
17 Aug 2019 15:44
Forum: Military Issues & History Forum
Topic: Indian Space Program: News & Discussion - Sept 2016
Replies: 4397
Views: 1072397

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

One advantage of nonstaged combustion is portions of engine can be separately tested before full firing
by prasannasimha
17 Aug 2019 15:41
Forum: Military Issues & History Forum
Topic: Indian Space Program: News & Discussion - Sept 2016
Replies: 4397
Views: 1072397

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

SC 200 partial engine hot test will be done sometime shortly till test stand is fully constructed. The engine perse would have been designed but full testing cannot be done till the test stand is completed
by prasannasimha
17 Aug 2019 01:01
Forum: Military Issues & History Forum
Topic: Indian Space Program: News & Discussion - Sept 2016
Replies: 4397
Views: 1072397

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

NORAD ID: 44441
Int'l Code: 2019-042A
Perigee: -1,193.5 km
Apogee: 404,883.5 km
Inclination: 21.8 °
Period: 15,759.1 minutes
Semi major axis: 208215 km
RCS: Unknown
Launch date: July 22, 2019
Source: India (IND)
Launch site: SRIHARIKOTA (SRI)
by prasannasimha
17 Aug 2019 00:26
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

NORAD ID: 44441
Int'l Code: 2019-042A
Perigee: -1,193.5 km
Apogee: 404,883.5 km
Inclination: 21.8 °
Period: 15,759.1 minutes
Semi major axis: 208215 km
RCS: Unknown
Launch date: July 22, 2019
Source: India (IND)
Launch site: SRIHARIKOTA (SRI)
by prasannasimha
14 Aug 2019 00:25
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

https://www.n2yo.com/?s=44441 shows the previous ground track so they did do an inclination change with the last earthbound maneuver

Image
by prasannasimha
14 Aug 2019 00:19
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

Is the point on the Pacific where the descending node point is ?
by prasannasimha
14 Aug 2019 00:15
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

Thanks. I was a bit confused seeing it heading to the middle of the pacific whereas the 3D animation on Satflare showed the perigee it over Peru like you said. Moons orbit is around 5.1 Deg to ecliptic so they will need an inclination change too ? https://upload.wikimedia.org/wikipedia/commons/thumb...
by prasannasimha
13 Aug 2019 23:16
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

Got to recheck where the groundtrace of perigee point is. Is it over middle of Paciific ocean or over South America ? Seeing the ground trace it looks like over middle of the Pacific Ocean.
by prasannasimha
13 Aug 2019 23:01
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

TLI at 3-4 AM IST
Image

Image
by prasannasimha
12 Aug 2019 22:05
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

https://pbs.twimg.com/media/EByDtBNUYAA_DXm.jpg Chandrayaan has crossed its apogee and now swinging back for the TLI burn on August 14th at 3 -4 AM TIME Mon, 12/08/2019 21:50:22 Latitude [deg] 2.08 Altitude [km] 143451.5 DEC J2000 [d:m:s] 1:26:05 Sun El.[deg] -42.8 (Deep Night)(UTC) Mon, 12/08/2019...
by prasannasimha
12 Aug 2019 13:54
Forum: Strategic Issues & International Relations Forum
Topic: J&K Union Territory-2019
Replies: 3745
Views: 706570

Re: J&K Union Territory-2019

^^ Policy formulator is Modi Doval/Shah are the executors of the policy on the ground Think Tank Vivekanand Foundation under Doval, Maj. General Bakshi , Col. RSN Singh and Pushpendra kulshrestha formulated policy. Last year 21 October Red Fort Flag ceremony was triggered by these 4 meeting Modi an...
by prasannasimha
12 Aug 2019 13:52
Forum: Strategic Issues & International Relations Forum
Topic: J&K Union Territory-2019
Replies: 3745
Views: 706570

Re: J&K Union Territory-2019

"Ek desh mein do Vidhan, do Pradhan aur Do Nishan nahi chalenge" (A single country can't have two constitutions, two prime ministers, and two national emblems)

This was said by Shyam Prasad Mukherjee in 1952
by prasannasimha
11 Aug 2019 22:22
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

That was control room and burn placement
by prasannasimha
06 Aug 2019 19:19
Forum: Strategic Issues & International Relations Forum
Topic: Articles 370 and 35A Repealed, J&K and Ladakh to be Separate Union Territories
Replies: 632
Views: 83301

Re: Articles 370 and 35A Repealed, J&K and Ladakh to be Separate Union Territories

351 Ayes 72 Noes and 1 abstains
J and K reorganization bill passed with 2/3rd (83%) majority in both LS and RS !
by prasannasimha
06 Aug 2019 18:54
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

Image
by prasannasimha
06 Aug 2019 17:49
Forum: Strategic Issues & International Relations Forum
Topic: Articles 370 and 35A Repealed, J&K and Ladakh to be Separate Union Territories
Replies: 632
Views: 83301

Re: Articles 370 and 35A Repealed, J&K and Ladakh to be Separate Union Territories

^^^^ Actually not quite true. 370 is more nuanced and very complicated. I dont claim to be an expert on it. … … All in all a kichdi manoeuver. Let's see if it stands the test of the courts. Courts can't do much. The AP reorganization bill is still in Supreme Court. Harish Salve on NDTV explained it...
by prasannasimha
05 Aug 2019 22:47
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

As far as EP propulsion goes let it be clear - you cannot beat physics and momentum = mass X velocity and current "regular" fuels have an ISP of max approx 450. However they have one great advantage they provide enough thrust in short period of time to allow us to escape earth. No ion engi...
by prasannasimha
05 Aug 2019 14:08
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

sanjaykumar wrote:Why not use a modular approach and boost assets separately into orbit? Assemble by docking finally orbiting astronauts in a module that can orbit the moon and also return to earth.

That is Indias plan 2 rockets with earth rendezvous for docking TLI and lunar orviting and descent
by prasannasimha
04 Aug 2019 23:26
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

No electric propulsion currently available will allow rapid transfer that allows man to get to the moon. EP will not allow a launch from earth - it can be used only for transfer after initial orbital injection and India will be doing one such GTO to GSO transfer in one of the coming flights.
by prasannasimha
04 Aug 2019 18:44
Forum: Strategic Issues & International Relations Forum
Topic: J&K News and Discussion - 2016
Replies: 3305
Views: 670292

Re: J&K News and Discussion - 2016

If one wanted to rename name it as Sharadapura
by prasannasimha
03 Aug 2019 00:30
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

Thry gave one additional set adter the launch. The caveat also mentioned below it is that these are provisional subject to the orbit achieved in every burn. They changed the prohisional time table as the orbit of first burn was so cl9se to the actual injection so first burn time was considerably red...
by prasannasimha
02 Aug 2019 20:05
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

Vivek K wrote:Question for the gurus - Are the changes in actual achieved orbits caused by the additional fuel load in the satellite?

Each orbit change is calculated based on the mass of fuel and craft before the burn.
by prasannasimha
02 Aug 2019 17:46
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

Chandrayaan2 update: Fourth earth bound maneuver Looks like a shortfall (0.84%) in the apogee : 277 x 89472 ( actual) vs 248 x 90229 ( planned ) - https://www.isro.gov.in/update/24-jul-2019/chandrayaan-%E2%80%93-2-update-optimised-mission-plan-of-chandrayaan-%E2%80%93-2-spacecraft. Anyway 2 more ea...
by prasannasimha
02 Aug 2019 16:52
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

Only one more earth bound manoeuvres. The one after that is TLI

Image
by prasannasimha
30 Jul 2019 10:07
Forum: Military Issues & History Forum
Topic: Chandrayan-2 Mission
Replies: 2274
Views: 342997

Re: Chandrayan-2 Mission

The moons gravity is fairly distorted due to its internal mass distribution ( due to the mechanism of its birth being gouged out die to Earth's collision with a Mars sized object , asteroid impacts and Lava flows. Please look up about "Mascons" and "Frozen orbits" The lower you g...

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