Indian Space Program: News & Discussion - Sept 2016

The Military Issues & History Forum is a venue to discuss issues relating to the military aspects of the Indian Armed Forces, whether the past, present or future. We request members to kindly stay within the mandate of this forum and keep their exchanges of views, on a civilised level, however vehemently any disagreement may be felt. All feedback regarding forum usage may be sent to the moderators using the Feedback Form or by clicking the Report Post Icon in any objectionable post for proper action. Please note that the views expressed by the Members and Moderators on these discussion boards are that of the individuals only and do not reflect the official policy or view of the Bharat-Rakshak.com Website. Copyright Violation is strictly prohibited and may result in revocation of your posting rights - please read the FAQ for full details. Users must also abide by the Forum Guidelines at all times.
Vips
BRFite
Posts: 1229
Joined: 14 Apr 2017 18:23

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

Postby Vips » 26 Nov 2018 18:31

Isro to launch 30 foreign sats and hi-tech imaging satellite on Nov 29.

Indian Space Research Organisation (Isro) is gearing up to launch hyperspectral imaging satellite (HySIS), an earth observation satellite, from the Sriharikota launch centre on Thursday morning. Over 30 foreign commercial satellites will be launched along with primary payload HySIS by the PSLV C43 rocket.

Talking to TOI, Isro chairman K Sivan said, "We are going to launch HySIS at 9.59 am on November 29 from Sriharikota. Over 30 foreign satellites, including nano and mini satellites, will also be launched along with the main payload. Out of the 30 commercial satellites, 23 are from the US."

The satellite, which can see in 55 spectral or colour bands from 630 km above the ground, will be used for a range of applications like agriculture, forestry and assessment of coastal zones, inland waters, soil and other geological environments. Being an earth observation satellite, HySIS will also be used by the military for surveillance purpose. The optical imaging detector array chip in the HySIS satellite has been designed by Isro's Ahmedabad-based Space Applications Centre and manufactured by its electronic arm, Semi-Conductor Laboratory, Chandigarh.

The hyspex technology is still an evolving science and has become a new global trend. Hyperspectral imaging combines the power of digital imaging and spectroscopy. It collects and processes information from across the electromagnetic spectrum. Hyspex imaging enables distinct identification of objects, material or processes on the Earth by reading the spectrum for each pixel of a scene from space.

Soon after the HySIS launch on November 29, Isro will shift its eye to the European spaceport as its heaviest commercial satellite Gsat11 weighing 5.7 tonnes will be launched from French Guiana on December 5 (December 4 evening according to Indian standard time).

The high-throughput satellite, which carries 40 transponders in the Ku-band and Ka-band frequencies, is capable of "providing high bandwidth connectivity" with up to 14 gigabit per second (GBPS) data transfer speed.

Gsat-11, which will help increase internet speed in the country, was earlier this year recalled from French Guiana in order to check for possible glitches. Isro felt the need to take the unusual step of recalling the satellite in April as a precaution especially after the failure of the Gsat-6A satellite mission around the same time.

arshyam
BRF Oldie
Posts: 2982
Joined: 11 Aug 2016 06:14

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

Postby arshyam » 26 Nov 2018 18:46

Will this be the first time they have two launches within a month?


Varoon Shekhar
BRFite
Posts: 1727
Joined: 03 Jan 2010 23:26

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

Postby Varoon Shekhar » 27 Nov 2018 19:13

arshyam wrote:Will this be the first time they have two launches within a month?


Nope, in 2017, the GSLV Mark 2 was launched on May 5th, and the Mark 3 on June 5th. Less than 3 weeks after that, the PSLV was launched on June 23.

Earlier this year, the GSLV Mark 2 ( with the ill fated GSAT 6A) went up on March 29th, and the PSLV with IRNSS-1I on April 12( 2 missions within 2 weeks). In Sept 2016, there was a GSLV and a PSLV within 18 days. These are 3 I can remember off the top of my head! :)

arshyam
BRF Oldie
Posts: 2982
Joined: 11 Aug 2016 06:14

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

Postby arshyam » 27 Nov 2018 19:49

^^ Thanks Varoon, that's good to know.

ramana
Forum Moderator
Posts: 50757
Joined: 01 Jan 1970 05:30

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

Postby ramana » 28 Nov 2018 06:01

Vips wrote:Isro to launch 30 foreign sats and hi-tech imaging satellite on Nov 29.

Indian Space Research Organisation (Isro) is gearing up to launch hyperspectral imaging satellite (HySIS), an earth observation satellite, from the Sriharikota launch centre on Thursday morning. Over 30 foreign commercial satellites will be launched along with primary payload HySIS by the PSLV C43 rocket.

Talking to TOI, Isro chairman K Sivan said, "We are going to launch HySIS at 9.59 am on November 29 from Sriharikota. Over 30 foreign satellites, including nano and mini satellites, will also be launched along with the main payload. Out of the 30 commercial satellites, 23 are from the US."

The satellite, which can see in 55 spectral or colour bands from 630 km above the ground, will be used for a range of applications like agriculture, forestry and assessment of coastal zones, inland waters, soil and other geological environments. Being an earth observation satellite, HySIS will also be used by the military for surveillance purpose. The optical imaging detector array chip in the HySIS satellite has been designed by Isro's Ahmedabad-based Space Applications Centre and manufactured by its electronic arm, Semi-Conductor Laboratory, Chandigarh.

The hyspex technology is still an evolving science and has become a new global trend. Hyperspectral imaging combines the power of digital imaging and spectroscopy. It collects and processes information from across the electromagnetic spectrum. Hyspex imaging enables distinct identification of objects, material or processes on the Earth by reading the spectrum for each pixel of a scene from space.

Soon after the HySIS launch on November 29, Isro will shift its eye to the European spaceport as its heaviest commercial satellite Gsat11 weighing 5.7 tonnes will be launched from French Guiana on December 5 (December 4 evening according to Indian standard time).

The high-throughput satellite, which carries 40 transponders in the Ku-band and Ka-band frequencies, is capable of "providing high bandwidth connectivity" with up to 14 gigabit per second (GBPS) data transfer speed.

Gsat-11, which will help increase internet speed in the country, was earlier this year recalled from French Guiana in order to check for possible glitches. Isro felt the need to take the unusual step of recalling the satellite in April as a precaution especially after the failure of the Gsat-6A satellite mission around the same time.



HySIS was a dream project for AVM Dev Ganesh (R) !!!
Hope he reads this report.

sum
BRF Oldie
Posts: 9821
Joined: 08 May 2007 17:04
Location: (IT-vity && DRDO) nagar

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

Postby sum » 28 Nov 2018 14:41

Was this posted? Seems to have tons of info and looks like a goldmine of data:
gisat pdf

Haridas
BRFite
Posts: 338
Joined: 26 Dec 2017 07:53

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

Postby Haridas » 28 Nov 2018 21:59

ramana wrote:
Vips wrote:Isro to launch 30 foreign sats and hi-tech imaging satellite on Nov 29.

Indian Space Research Organisation (Isro) is gearing up to launch hyperspectral imaging satellite (HySIS), an earth observation satellite, from the Sriharikota launch centre on Thursday morning. Over 30 foreign commercial satellites will be launched along with primary payload HySIS by the PSLV C43 rocket.

Talking to TOI, Isro chairman K Sivan said, "We are going to launch HySIS at 9.59 am on November 29 from Sriharikota. Over 30 foreign satellites, including nano and mini satellites, will also be launched along with the main payload. Out of the 30 commercial satellites, 23 are from the US."

The satellite, which can see in 55 spectral or colour bands from 630 km above the ground, will be used for a range of applications like agriculture, forestry and assessment of coastal zones, inland waters, soil and other geological environments. Being an earth observation satellite, HySIS will also be used by the military for surveillance purpose. The optical imaging detector array chip in the HySIS satellite has been designed by Isro's Ahmedabad-based Space Applications Centre and manufactured by its electronic arm, Semi-Conductor Laboratory, Chandigarh.

The hyspex technology is still an evolving science and has become a new global trend. Hyperspectral imaging combines the power of digital imaging and spectroscopy. It collects and processes information from across the electromagnetic spectrum. Hyspex imaging enables distinct identification of objects, material or processes on the Earth by reading the spectrum for each pixel of a scene from space.

Soon after the HySIS launch on November 29, Isro will shift its eye to the European spaceport as its heaviest commercial satellite Gsat11 weighing 5.7 tonnes will be launched from French Guiana on December 5 (December 4 evening according to Indian standard time).

The high-throughput satellite, which carries 40 transponders in the Ku-band and Ka-band frequencies, is capable of "providing high bandwidth connectivity" with up to 14 gigabit per second (GBPS) data transfer speed.

Gsat-11, which will help increase internet speed in the country, was earlier this year recalled from French Guiana in order to check for possible glitches. Isro felt the need to take the unusual step of recalling the satellite in April as a precaution especially after the failure of the Gsat-6A satellite mission around the same time.



HySIS was a dream project for AVM Dev Ganesh (R) !!!
Hope he reads this report.

I met AVM Dev Ganesh at his house when he was head of AFRO Air HQ. That time he was my brother's CO.

AFAIK this is the fastest method to resolve objects from hyperspectral image.

https://www.researchgate.net/publicatio ... d_Learning

http://spie.org/Publications/Proceeding ... /12.603382
Last edited by Haridas on 28 Nov 2018 22:02, edited 1 time in total.

Vips
BRFite
Posts: 1229
Joined: 14 Apr 2017 18:23

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

Postby Vips » 28 Nov 2018 22:01

India's heaviest communication satellite to orbit in space on December 5.

India's heaviest communication satellite with high throughput GSAT-11 will be put into orbit by Ariane-5 rocket of Arianespace from French Guiana on December 5, 2018, the Indian space agency said. According to Indian Space Research Organisation (ISRO), the GSAT-11 weighing 5,854 kg is the heaviest satellite built by it.

The satellite is scheduled for launch on board Ariane-5 launch vehicle from French Guiana. The satellite will be initially placed in the Geosynchronous Transfer Orbit and will subsequently be raised to geostationary orbit by firing the satellite's on-board motor.

According to ISRO, GSAT-11 is the forerunner in a series of advanced communications satellites with multi-spot beam antenna coverage over Indian mainland and islands. The satellite with a mission life of 15 years will have 32 user beams (Ku band) and eight hub beams (Ka band) and the throughput data rate of 16 Gbps.

GSAT-11 will play a vital role in providing broadband services across the country. It will also provide a platform to demonstrate new generation applications. The Indian space agency said the GSAT-11 will be used to meet the increased data demands with high data rates over regions using spot beams. The satellite will support BharathNet connecting gram panchayat for e-governance and digital platforms; VSAT terminals and for enterprise network and consumer broadband applications.

prasannasimha
Forum Moderator
Posts: 881
Joined: 15 Aug 2016 00:22

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

Postby prasannasimha » 28 Nov 2018 22:06

ISRO

Verified account

@isro
54m54 minutes ago
More
Update #5
#ISROMissions
#HysIS

Propellant filling for the second stage (PS2) of #PSLVC43 begins.

A Nandy
BR Mainsite Crew
Posts: 206
Joined: 06 Sep 2009 23:39

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

Postby A Nandy » 29 Nov 2018 02:04


Prithwiraj
BRFite
Posts: 121
Joined: 21 Dec 2016 18:48

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

Postby Prithwiraj » 29 Nov 2018 04:47

At this rate bay of bengal floor will be littered with pslv and gslv stages.. creating a nice coral colony!

A Nandy
BR Mainsite Crew
Posts: 206
Joined: 06 Sep 2009 23:39

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

Postby A Nandy » 29 Nov 2018 09:48

Up and about sleepy heads!!! :D

ISRO about to have yet another "prakshe pan"!!! :lol:

https://www.isro.gov.in/pslv-c43-hysis- ... sis-misson

http://cdn.24fd.com/e18/11/isro/29/index.html

T-16

Prasad
BRF Oldie
Posts: 6977
Joined: 16 Nov 2007 00:53
Location: Chennai

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

Postby Prasad » 29 Nov 2018 10:07

Lift-off & 1st stage naarmal. First stage separated.

Aarvee
BRFite -Trainee
Posts: 82
Joined: 14 Oct 2016 07:43

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

Postby Aarvee » 29 Nov 2018 10:09

lift off and first stage naarmal :D

I know the travel path is as expected but it felt pretty sharply banking so soon after lift off. Am I seeing things?

A Nandy
BR Mainsite Crew
Posts: 206
Joined: 06 Sep 2009 23:39

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

Postby A Nandy » 29 Nov 2018 10:09

Anyone getting the live feed?

dwaipayandhar
BRFite -Trainee
Posts: 3
Joined: 15 Aug 2016 00:07

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

Postby dwaipayandhar » 29 Nov 2018 10:11

LIve feed not working on ISRO website

Prasad
BRF Oldie
Posts: 6977
Joined: 16 Nov 2007 00:53
Location: Chennai

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

Postby Prasad » 29 Nov 2018 10:15

4th stage parfaarmans naarmal

Mort Walker
BRF Oldie
Posts: 6999
Joined: 31 May 2004 11:31
Location: The rings around Uranus.

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

Postby Mort Walker » 29 Nov 2018 10:18

A Nandy wrote:Anyone getting the live feed?


I'm following live on Spaceflight Now: https://spaceflightnow.com/2018/11/28/p ... us-center/

Mort Walker
BRF Oldie
Posts: 6999
Joined: 31 May 2004 11:31
Location: The rings around Uranus.

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

Postby Mort Walker » 29 Nov 2018 10:19

T+plus 12 minutes. The PSLV is now about 1,562 miles (2,514 kilometers) downrange from the launch pad, after initially flying to the southeast from the Sriharikota launch site, then turning to the south to ensure the rocket does not fly over Sri Lanka.

Mort Walker
BRF Oldie
Posts: 6999
Joined: 31 May 2004 11:31
Location: The rings around Uranus.

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

Postby Mort Walker » 29 Nov 2018 10:20

PS4 second restart at 11:25 IST.

Mort Walker
BRF Oldie
Posts: 6999
Joined: 31 May 2004 11:31
Location: The rings around Uranus.

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

Postby Mort Walker » 29 Nov 2018 10:22

T+plus 15 minutes. Performance of the fourth stage is reported normal. The fourth stage will continue firing until T+plus 16 minutes, 34 seconds, followed less than 50 seconds later by separation of the HysIS satellite.

JayS
Forum Moderator
Posts: 3599
Joined: 11 Aug 2016 06:14

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

Postby JayS » 29 Nov 2018 10:23

One can watch on DD Live Youtube channel as well.

Rather long mission with two restarts and almost full orbit aroubd earth once.

Mort Walker
BRF Oldie
Posts: 6999
Joined: 31 May 2004 11:31
Location: The rings around Uranus.

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

Postby Mort Walker » 29 Nov 2018 10:23

PS4 should be shutting down now. 992 seconds after start.

Prasad
BRF Oldie
Posts: 6977
Joined: 16 Nov 2007 00:53
Location: Chennai

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

Postby Prasad » 29 Nov 2018 10:23

HySIS sat separated.

Mort Walker
BRF Oldie
Posts: 6999
Joined: 31 May 2004 11:31
Location: The rings around Uranus.

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

Postby Mort Walker » 29 Nov 2018 10:25

HysIS now injected successfully in sun synchronous orbit.

Vips
BRFite
Posts: 1229
Joined: 14 Apr 2017 18:23

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

Postby Vips » 29 Nov 2018 18:47

India increasing production of solid fuel boosters for rockets.

The Indian space agency is increasing the production of its solid boosters to power more number of rockets that it is planning to send up carrying satellites, the agency said.

According to the Indian Space Research Organisation (ISRO), its Solid Propellant Space Booster Plant (SPROB) is setting up 29 additional facilities with innovative technical aspects and fail-safe process automation to increase the annual production by several times.

The space agency said SPROB is now carrying out a challenging task to deliver 12 numbers of S139 motors by 2019 end, which is double the present capacity. The S139 motors powers the first stage of Indian rocket Polar Satellite Launch Vehicle (PSLV).

The plant is located at Satish Dhawan Space Centre (SDSC) here where the Indian rocket port is also located.

On Wednesday, ISRO celebrated the completion of 1,000th sold motor casting by SPROB.

For developing the essential expertise in large Solid Rocket Motors, SPROB was established at Sriharikota and commissioned in 1977 with the realisation of a one metre diameter monolithic motor for SLV-3 (Space Launch Vehicle-3).

According to ISRO, in the 1980s, the requirement of the operational PSLV called for a major expansion of the scope and capacity of the facilities at SPROB.

This necessitated quantum shift in propellant formulation technology using the indigenously developed HTPB binder and vertical propellant mixers.

Self-reliance in solid propellant production was achieved by indigenous development and realisation of several specialised equipment. For manufacturing the massive S200 solid rocket motors of GSLV MkIII (Geosynchronous Satellite Launch Vehicle Mk III), a new plant was built at SPROB.

Successful commissioning of this vast with state of the art plant in 2008 has enabled the Indian space programme to evolve complex missions like Chandrayaan-2 and Gaganyaan.

ramana
Forum Moderator
Posts: 50757
Joined: 01 Jan 1970 05:30

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

Postby ramana » 30 Nov 2018 02:23

Prasad, Thanks for the updates.
Please do post the first HySIS image.
Need to send to AVM Ganesh!!!!

Jayram
BRFite
Posts: 277
Joined: 14 Jan 2003 12:31

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

Postby Jayram » 30 Nov 2018 03:18

From Space flight
https://spaceflightnow.com/2018/11/29/indian-rocket-launches-31-satellites/

The 837-pound (380-kilogram) HysIS satellite separated from the PSLV’s fourth stage approximately 17 minutes after liftoff as the rocket headed south over the Indian Ocean. An on-board camera showed the HysIS spacecraft flying away from the rocket in orbit.

The PSLV’s upper stage continued its flight, flying over Antarctica before reigniting two more times to lower its altitude to roughly 313 miles (504 kilometers), setting the stage for deployment of 30 more spacecraft.

The lower orbit targeted for release of the 30 secondary payloads is expected to ensure the satellites are pulled back to Earth for destructive re-entries in the coming decades, and they do not become a source of long-term space debris.


The launch marked the first from India with satellites for Australia, Colombia, Malaysia and Spain. With Thursday’s mission, the PSLV has launched 45 times — 43 of which were successful — and carried 269 spacecraft to orbit for international customers, plus 53 Indian spacecraft.


K. Sivan, ISRO’s chairman, said HysIS is a “satellite with state-of-the-art technology.”

“The heart of the system required for the Hyperspectral Imaging Satellite is basically the optical imaging detector chip,” Sivan said in remarks after the launch. “This chip was indigenously designed and devleoped by the Space Applications Center of ISRO.”

The second part of the mission was for our customers,” Sivan continued. “The way the PSLV injected all our customer satellites in their designated home, I’m sure that our customers are very happy to see their babies delivered to the their home safely and precisely.”


Very positive report .. Great going not required but anyway Congrats ISRO

Ashokk
BRFite
Posts: 330
Joined: 11 Aug 2016 06:14

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

Postby Ashokk » 30 Nov 2018 15:50

A minesweeper in the sky that assists farming too
A pack of sniffer dogs and metal detectors saved a group of CRPF jawans on a routine morning drill from a powerful landmine near a village in Odisha a few months ago. More than 3,700 people including military personnel have died stepping on landmines planted on or under soil in India in 17 years, a study shows.

Soon, India’s earth observation satellite HysIS (Hyperspectral Imaging Satellite), launched by a PSLV + on Thursday, will do the job of mine mapping minus the risk, from an altitude of more than 600km in space. Its cameras will look at earth in a whole new way that it would detect tyre tracks on a muddy road and on snow, differentiate a healthy crop from dead ones, spot various minerals at once and locate water streams underneath a thick canopy of trees.

“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.

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.

HysIS is better than the existing Indian earth observation satellites as it gives finer details of the objects. “The human eye can see only in a combination of red, green and blue. Hyperspectral imagers can see and capture an array of colours present in between any two colours in the electromagnetic spectrum,” said A S Kiran Kumar, former ISRO chairman and a satellite expert.


The imager in HysIS can see the earth in 55 spectral or colour bands. This means by looking at, say a patch of land, it can see the soil, what’s immediately beneath, and also if there is a metal or a mineral there. “It can differentiate between a dead plant and a live one. That’s being hyperspectral,” said Khankhoje. On the flip side, HysIS, unlike satellites with synthetic aperture radars, cannot see in the dark. In sunlight,

they can see objects as all as one metre. This makes it useful for agriculture, forestry and assessment of coastal zones, inland waters, soil and other geological environments, besides surveillance. A scientist with a national coastal research laboratory said the satellite may help study water quality and map mangroves along the coast.


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

jaysimha
BRFite
Posts: 681
Joined: 20 Dec 2017 14:30

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

Postby jaysimha » 30 Nov 2018 17:36

Heartening to know what all Isro is doing other than building rockets and satellites.

Workshop Cum Training Programme cum kumbh mela on
COASTAL AND OCEAN MANAGEMENT
JANUARY 28 - FEBRUARY 1, 2019

https://www.iirs.gov.in/iirs/sites/defa ... n_2019.pdf


One Day Online Workshop on
Crowd Sourcing and Participatory GIS
https://www.iirs.gov.in/iirs/sites/defa ... df/wrk.pdf

Workshop on Crowd Sourcing and Participatory GIS have been Postponed to December 21,2018

Singha
BRF Oldie
Posts: 63609
Joined: 13 Aug 2004 19:42
Location: the grasshopper lies heavy

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

Postby Singha » 30 Nov 2018 17:50

IAF will get its own comms relay sat soon incl from airborne platforms

https://en.wikipedia.org/wiki/GSAT-7A

SBajwa
BRF Oldie
Posts: 4901
Joined: 10 Jan 2006 21:35
Location: Attari

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

Postby SBajwa » 30 Nov 2018 22:23

prasannasimha wrote:Nov 16, 2018 : GSLV Mk III-D2/GSAT-29 Mission: The second orbit raising operation of GSAT-29 satellite has been successfully carried out today (November 16, 2018) by firing the Liquid Apogee Motor (LAM) engine of the satellite at 1027 Hrs IST for a duration of 4988 sec


4988 seconds seems too much it is 1 hour and 23 minutes.

Singha
BRF Oldie
Posts: 63609
Joined: 13 Aug 2004 19:42
Location: the grasshopper lies heavy

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

Postby Singha » 30 Nov 2018 22:34

use the media filter and lose the trailing 8.

Rakesh
Forum Moderator
Posts: 5973
Joined: 15 Jan 2004 12:31
Location: Planet Earth
Contact:

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

Postby Rakesh » 01 Dec 2018 04:30

https://twitter.com/IndianDefenceRA/sta ... 7224400897 ---> Very beautiful images of Hyper Spectral Imaging Satellite of ISRO.

Image

Image

Image

naruto
BRFite
Posts: 104
Joined: 23 Aug 2016 08:59

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

Postby naruto » 01 Dec 2018 10:11

SBajwa wrote:4988 seconds seems too much it is 1 hour and 23 minutes.

Singha wrote:use the media filter and lose the trailing 8.


The ISRO website also says so: https://www.isro.gov.in/update/15-nov-2018/gslv-mk-iii-d2-gsat-29-mission-first-orbit-raising-operation-of-gsat-29-satellite and https://www.isro.gov.in/update/16-nov-2018/gslv-mk-iii-d2-gsat-29-mission-second-orbit-raising-operation-of-gsat-29
I too noticed it and wondered why, both the firings cumulative is almost 2 hr 45 min. I notice the inclination being changed from 21.46 deg before first burn to 0.31 deg after second burn. Does changing inclination take more fuel or circularising the orbit? If the intended inclination is near 0 deg, why did they launch into 21.46 deg inclination. (I have very less knowledge about orbital mechanics, so asking)

prasannasimha
Forum Moderator
Posts: 881
Joined: 15 Aug 2016 00:22

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

Postby prasannasimha » 01 Dec 2018 19:02

naruto wrote:
SBajwa wrote:4988 seconds seems too much it is 1 hour and 23 minutes.

Singha wrote:use the media filter and lose the trailing 8.


The ISRO website also says so: https://www.isro.gov.in/update/15-nov-2018/gslv-mk-iii-d2-gsat-29-mission-first-orbit-raising-operation-of-gsat-29-satellite and https://www.isro.gov.in/update/16-nov-2018/gslv-mk-iii-d2-gsat-29-mission-second-orbit-raising-operation-of-gsat-29
I too noticed it and wondered why, both the firings cumulative is almost 2 hr 45 min. I notice the inclination being changed from 21.46 deg before first burn to 0.31 deg after second burn. Does changing inclination take more fuel or circularising the orbit? If the intended inclination is near 0 deg, why did they launch into 21.46 deg inclination. (I have very less knowledge about orbital mechanics, so asking)


\The firing time I posted is correct.

Change of inclination is more expensive wrt fuel and time whereas change of orbit is less costly in terms of fuel and time. In fact the two most fuel expensive portions are first lobbing the satellite and next is orbital inclination change.

We can only launch at the degree of latitude(lowest is for direct equatorial launch from Sea launch next is Kourou , after that is SHAR, next Cape Kennedy->Baikanour and finally Plestetsk . Each will lob the craft and then have to change inclination. The lowest inclination change is from the equator for a GSO orbit

Please refer

https://en.wikipedia.org/wiki/Orbital_inclination_change

Haridas
BRFite
Posts: 338
Joined: 26 Dec 2017 07:53

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

Postby Haridas » 01 Dec 2018 23:22

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.

Amber G.
BRF Oldie
Posts: 6118
Joined: 17 Dec 2002 12:31
Location: Ohio, USA

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

Postby Amber G. » 02 Dec 2018 02:14

naruto wrote:...
I too noticed it and wondered why, both the firings cumulative is almost 2 hr 45 min. I notice the inclination being changed from 21.46 deg before first burn to 0.31 deg after second burn. Does changing inclination take more fuel or circularising the orbit? If the intended inclination is near 0 deg, why did they launch into 21.46 deg inclination. (I have very less knowledge about orbital mechanics, so asking)

To add - Allow me to explain the orbital mechanics in simple terms. (For details see any good text book -- I am trying to put in simple, yet technically correct form).

Let us assume the situation after last firing of rocket is over. Let us also neglect air-resistance (it is so high up etc) and small perturbation due to non spherical shape of the earth, effects due to moon or other astronomical bodies etc..) to make things simple. (Effects due to them is very small anyway).

1 - Once firing of rockets has stopped - All orbits are elliptical with center of earth at the focus. The orbit is fixed more or less - remember we are ignoring things mentioned in the previous paragraph. Here the orbital time (total time to go around center of earth) is constant. It depends only on semi-major axis (average of perigee and apogee). Thus angular velocity may vary within one revolution but average remains constant. The distance from earth may change a little but average is again constant. The orbit may be inclined - that is it is not exactly above the equator - so the "latitude" of the satellite may vary (goes towards north and later towards south, maximum value reached is called "inclination") but at two times (and on average) it is exactly "above the equator".

2 - For a "geostationary" satellite the orbit is (a) - circular and (b) zero inclination. This means the satellite always remains above the equator. The distance from earth is also constant. Hence the angular velocity is also constant. If this angular velocity is same as spin of the earth the satellite will always remain fixed in the sky. To achieve this orbit one has to fire a rocket and change it from the previous orbit. To do this one fires a rocket and gives two kinds delta-v.

To change from elliptical to circular orbit two things must happen. The position must be such that it is exactly the same distance away as the final circular orbit will be (IOW the timing must be right). For most efficient value this position is near the perigee. The delta-V is the difference between the previous velocity (which is higher than average at perigee) and the new velocity for circular orbit. This is fairly easy to calculate. (see note 1 in the next post). If you calculate it, it is fairly modest. Of course we do it all the time. As each firing of rocket makes the orbit more circular.

To change the inclination again the timing must be right. First the current position must be at the zero latitude. The delta-V here, again easy to see, = 2* v * sin (inclination/2). Again if you see (see note 2 in the next post) for a typical case it is much more that the first case.

One thing to note here that if our launching point is on the equator we will not need to adjust the inclination. Higher North/south the the launch point on earth is we will have to use more fuel to reduce inclinition. (again with each stage, the inclination of the orbit is reduced.)

Hope this helps. I will put those two "notes" in the next post. :)

Amber G.
BRF Oldie
Posts: 6118
Joined: 17 Dec 2002 12:31
Location: Ohio, USA

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

Postby Amber G. » 02 Dec 2018 03:10

Notes (for the above post).
To practically calculate, all you need:
Units: distance in meters, time in seconds , measured from center of earth.

r = distance from center of earth to the current location of sat. - use unit meters.
v = velocity (current) of the sat - use unit meter/sec
a = "average" distance = (p+q)/2) ==> p= perigee, q= apogee)
k ≈ 4 * 10^14

First thing is if you know Time period (=T) , you know "a" (or vice-versa) by this formula T=2*pi* sqrt(a^3/k) which simplified for earth is T≈ (3.14)*10^(-7)*sqrt(a^3).


Then v^2 = k (2/r - 1/a) ≈ 4*10^14(2/r-1/a)

Now it is extremely easy to calculate delta-v.
(for circular orbit, a=r so new v needed can be calculated giving us delta-v etc. To change inclination of orbit, you need delta-v=2*V*sin(i/2)) Calculate this for typical value to see for yourself.

Hope this helps.


Return to “Military Issues & History Forum”

Who is online

Users browsing this forum: Austin, Google [Bot], rkhanna, sankum and 40 guests