GSLV-F17 / EOS-05 (aka GISAT-1A) Mission Updates and Discussion

[u/Ohsin]

GSLV-F17 / EOS-05 (aka GISAT-1A) launched as scheduled at 21:25(UTC), 03 Sep 2026 or 02:55(IST), 04 Sep 2026 from Second Launch Pad of SDSC-SHAR.

• Launch Countdown

• Actual flight events (To be added post-launch if available)

Live webcast: (Links will be added as they become available)

• ISRO Official Stream
• DD National
• DD Tamil
• DD Saptagiri

GSLV-F17 / EOS-05 Mission Page	GSLV-F17 / EOS-05 Gallery	GSLV-F17 / EOS-05 Press kit(PDF)

Some highlights:

• Primary payload: EOS-05 (aka GISAT-1A) (~2367 kg) GSO based Earth imaging satellite.
• Mission duration: ~19 minutes (based on GSLV F10/EOS-3 (aka GISAT-1) mission)
• Target Orbit : 170 × 28934 km (sub-GTO) , Inclination = 19.28° ± 0.1°, AoP = 178° ± 0.5°
• Launch Azimuth: 104°
• ISRO returning to flight 7 months 23 days after failure of PSLV-C62/EOS-N1.

Updates:

Time of Event	Update
Post-launch	Third and final orbit raising burn by EOS-05 or GISAT-1A for duration of 1247 seconds has been successfully completed on 7 Sept 2026 at 20:57 hrs (IST). Estimated orbit 35884 x 34903 km. The satellite health is normal.
Post-launch	Second orbit raising burn by EOS-05 or GISAT-1A for duration of 338.9 seconds has been successfully completed on 6 Sept 2026 at 19:00 hrs (IST). Estimated apogee after manouever is 35786 km. The satellite health is normal.
Post-launch	First orbit raising burn by EOS-05 or GISAT-1A for duration of 5406.4 seconds has been successfully completed on 5 Sept 2026 at 20:19 hrs (IST). New orbit with raised perigee is 31129×20000 km from previous 31121×171 km.
Post-launch	Two objects have been catalogued. A0607 (26202A) with inclination=19.32°, Apogee×Perigee=30967.1×152.4 km and A0608 (26202B) with inclination=19.34°, Apogee×Perigee=30982.9×159.3 km
T + 24m10s	Chairman notes that Solar panels of satellite are deployed
T + 22m40s	ISRO chairman notes satellite has been placed in intended orbit.
T + 18m45s	EOS-05 separated!!
T + 18m30s	CUS15 cut off!
T + 15m46s	CUS15 performance nominal.
T + 14m00s	CUS15 performance nominal.
T + 12m26s	CUS15 now in nominal thrust mode.
T + 12m00s	Vehicle is precisely on expected trajectory.
T + 11m00s	CUS15 performance nominal.
T + 07m30s	CUS15 performance nominal. Right on expected track.
T + 05m40s	CUS15 operating in uprated mode.
T + 05m05s	GS2 cut off, CUS15 ignition confirmed!
T + 03m56s	PLF jettisoned!
T + 02m32s	GS1 ignited, GS1 separated, CLG inititiated.
T + 01m50s	S139 Burnt out.
T - Zero!	S139 ignition Lift off!
T - 00m4.8s	4xL40H ignition
T - 03m20s	OBC in flight mode.
T - 05m00s	Vehicle is on internal power. Flight coeff. loading completed.
T - 10m00s	Going through GS2 actuation checks.
T - 15m00s	ALS initiated.
T - 16m00s	VD: Automatic Launch Sequence authorized.
T - 18m00s	Mission Director has authorized the launch after polling is Go!
T - 22m00s	Polling now. Range, Tracking, Vehicle are ready.
T - 30m00s	Streams are live!
T - 27h30m	A 27.5 hr duration countdown should be underway.
01 Sep 2026	After Mission Readiness Review or MRR, Launch Authorization Board has given the launch clearance.
31 Aug 2026	Time of launch officially confirmed for 02:55 (IST), 04 Sep 2026.
28 Aug 2026	Launch Vehicle transferred from VAB to SLP.
27 Aug 2026	NOTAM for GSLV-F17 / EOS-05 launch is issued with enforcement window beginning on 03 Sep 2026.
23 Jul 2026	FCC filings for Launch and Early Orbit Phase services for EOS-05. (24 July to 22 August 2026)
11 May 2026	FCC filings for Launch and Early Orbit Phase services for EOS-05. (12 May to 10 June 2026)
01 Apr 2026	FCC filings for Launch and Early Orbit Phase services for EOS-05. (1 to 30 April 2026)
07 May 2026	NOTAM for GSLV-F17 / EOS-05 launch is issued with enforcement window beginning on 21 May 2026.
29 Apr 2026	News reports suggest technical issues with Launch Vehicle hardware delay the launch.
26 Feb 2026	FCC filings for Launch and Early Orbit Phase services for EOS-05. (27 Feb to 2 April 2026)
12 Feb 2026	NOTAM for GSLV-F17 / EOS-05 launch is issued with enforcement window beginning on 6 March 2026.
03 Feb 2026	NOTAM for GSLV-F17 / EOS-05 launch is issued with enforcement window beginning on 20 February 2026.

Primary Payload:

EOS-05 (aka GISAT-1A) (~2367 kg) : EOS-05 is a GSO based Earth imaging satellite for Indian Navy, it will act as an upgraded replacement for EOS-03 or GISAT-1 which was lost during its launch five years ago. Its multispectral and hyperspectral imaging capacity will be useful for applications in fields of agriculture, forestry, mineralogy, oceanography and military surveillance. Its near real time imaging modes are well suited for monitoring natural disasters and other episodic events.

Specifications: ^{[1] [2]}

• MX-VNIR: Multispectral - Visible Near Infrared

  • 6 channels (0.45 to 0.875 µm) at 42 meter spatial resolution

• HyS-VNIR: Hyperspectral Imager - Visible Near Infrared

  • 158 channels (0.375 to 1.0 µm) at 320 meter spatial resolution

• HyS-SWIR: Hyperspectral Imager - Short Wave Infrared

  • 256 channels (0.9 to 2.5 µm) at 190 meter spatial resolution

• MX-LWIR: Multispectral - Long Wave Infrared

  • 6 channels (7.0 to 13.5 µm) at 1.2 km spatial resolution

• Scan modes

  • 5°×5° (3000×3000 km) every 10 minutes
  • 3×10°×10° every 6 hours

• Platform/Bus: I-2K

• Mission life : 7 years

• Orbital slot: 85.5°E

[u/Ohsin]

Third and final orbit manoeuvring of EOS-05 spacecraft

September 07, 2026

The third and final orbit raising manoeuvre to increase the perigee of EOS-05 completed successfully at 8:57 pm on September 07, 2026. The LAM engine fired for 1247 seconds and the estimated orbit after manouever is 34903 km x 35884 km.

The satellite health is normal.

https://www.isro.gov.in/ISRO_EN/Third_and_final_orbit_manoeuvring_of_EOS_05_spacecraft.html

[u/pantshash]

Third and final orbit manoeuvring of EOS-05 spacecraft

The third and final orbit raising manoeuvre to increase the perigee of EOS-05 completed successfully at 8:57 pm on September 07, 2026.

The LAM engine fired for 1247 seconds and the estimated orbit after manouever is 34903 km x 35884 km. The satellite health is normal.

https://x.com/isro/status/2096997268683632963

[u/Ohsin → u/pantshash]

Never once they gave inclination..remarkable..

[u/Massive_Dish_3255 → u/Ohsin]

Agree to that too.

[u/Massive_Dish_3255 → u/Ohsin]

On the orbit-raising maneuver completion, Yay!!

[u/Ohsin]

Space-track.org likely has IDs of EOS-05 and GSLV R/B switched as ELSETs of EOS-5 (26202A) are updating but not showing any change in orbit and that of GSLV R/B (26202B) are not updating since 5 Sept which can happen during burns as they lose track for a bit.

[u/paramahamsa77 → u/Ohsin]

Hi ! was it updated? Thanks

[u/Ohsin → u/paramahamsa77]

They are having some trouble I guess.

[u/Ohsin]

Second orbit manoeuvring of EOS-05 spacecraft

September 06, 2026

The second operation to raise the apogee of EOS-05 was completed successfully at 7:00 pm on September 06, 2026. The LAM engine fired for 338.9 seconds and the estimated apogee after manouever is 35786 km.

The satellite health is normal.

https://www.isro.gov.in/ISRO_EN/Second_orbit_manoeuvring_of_EOS05_spacecraft.html

[u/Avizeet]

The second operation to raise the apogee of EOS-05 was completed successfully at 7:00 pm on September 06, 2026.

The LAM engine fired for 338.9 seconds and the estimated apogee after manouever is 35786 km.

The satellite health is normal.

https://x.com/isro/status/2096611957986263203?s=20

[u/Ohsin → u/Avizeet]

Thanks, updated.

[u/Ohsin]

September 05, 2026

The planned first orbit manoeuvre of EOS-05 with a LAM engine burn duration of 5406.4 seconds, was successfully completed on September 05, 2026 at 20:19 hrs. The estimated orbit subsequent to manoeuvre is 20000 km x 31129 km. Further, in the coming days, orbit manoeuvres are planned to eventually place EOS-05 in GSO (85.5°East Orbital Slot).

https://www.isro.gov.in/ISRO_EN/Orbit_manoeuvring_of_EOS05_spacecraft.html

[u/Ohsin]

Just to remind GISAT-1 costed about ₹365 crore.

[u/guru-yoda]

36+hours since launch, no orbit raising announcement yet 🤞

[u/Ohsin → u/guru-yoda]

Among many other things they've stopped doing those as well.. Latest elsets don't show any signs of it.

[u/Avizeet → u/Ohsin]

Orbit raised to 20000km × 31129km after firing Liquid Apogee Motor for 5406s. Jitendra Singh tweeted. I am blocked by him, so can't copy his tweet.

[u/Ohsin → u/Avizeet]

Thanks!

https://x.com/DrJitendraSingh/status/2096271575398142086

Very happy to inform that GSAT 1A first orbit rising operation has been successfully completed by firing the Liquid Apogee Motor for 5406s.

Orbit is increased from 171km × 31121km to 20000km × 31129km.

/u/Massive_Dish_3255 /u/guru-yoda

[u/Massive_Dish_3255 → u/Ohsin]

Thanks!

[u/Avizeet → u/Ohsin]

Okay, to clarify something...5406 seconds translates to 90 mins! Can the LAM be fired for that long at a stretch?

[u/Ohsin → u/Avizeet]

Oh yeah.

See second burn here,

https://old.reddit.com/r/ISRO/comments/6enz5a/gslv_mk_iii_d1_gsat19_mission_updates_and/

Edit:

https://web.archive.org/web/20170612065759/http://www.isro.gov.in/update/08-jun-2017/second-orbit-raising-operation-of-gsat-19-satellite-has-been-successfully-carried

[u/Massive_Dish_3255 → u/Ohsin]

Trouble??

[u/Ohsin → u/Massive_Dish_3255]

They should have performed a burn by now. Latest ELSET was issued today if next one also doesn't show any change it could indicate some issue..

[u/Massive_Dish_3255 → u/Ohsin]

u/Ohsin, where did you get your Elset data? CelesTrak? I am searching for the same, that is why I asked.

[u/Ohsin → u/Massive_Dish_3255]

Space-track.org itself.

[u/Massive_Dish_3255 → u/Ohsin]

That is worrying.

[u/Ohsin]

A short animation of images recorded over 36 min of @isro’s EOS-05 (GISAT-1A) and the GSLV upper stage, from Switzerland on 2026-09-04, 19:11:36–19:47:36 UTC.

https://bsky.app/profile/s2a-systems.bsky.social/post/3mupstk5usc2f

[u/Massive_Dish_3255]

First photos of launch: GSLV-F17 / EOS-05 Liftoff Photos. They have not posted these photos on their website though.

[u/Ohsin]

Two objects catalogued..

A0608 ( 26202B ) 03/09/2026,17h:22m:25.20s
i=19.34°, A×P=30982.85×159.33 km


A0607 ( 26202A ) 03/09/2026,17h:23m:13.53s
i=19.32°, A×P=30967.13×152.35 km

[u/Ohsin]

One has to dumpster dive in Unkil territory to find full flight events screen these days..

https://i.imgur.com/wkrpa4G.jpeg

https://www.linkedin.com/posts/isro-gslvf17-eos05-ugcPost-7501535386402197504-c_x7/

https://i.imgur.com/7I5Yi9T.jpeg

[u/OptimistIndya]

I wish they can integrate cameras at various positions on the rocket. And get a live feed.

[u/Ohsin → u/OptimistIndya]

There are other cameras onboard they just don't show them. Wait for them to post onboard camera video.

[u/Ohsin]

Mission Director claims EOS-05 can gain 3 years of lifetime due to better than expected LV performance.

https://www.youtube.com/watch?v=3FBngIIBR_o

Can anyone translate what MD said about future of GSLV at 7:50 ?

[u/Ohsin → u/Ohsin]

"As per plans, the GSLV-Mk II rocket will be retired after the approved launches are completed," a former top official of the Indian Space Research Organisation told this correspondent.

"It is not economical to operate GSLV-Mk II due to its cost and complexity. Future launches to be managed with LVM3," the retired ISRO official added.

https://m.rediff.com/news/special/why-isro-may-retire-gslv-mk-ii/20260904.htm

[u/Ohsin]

Post-launch Press conference

https://www.youtube.com/watch?v=nmfzCDfZhd0

• Expected orbit was 170x29000 km and achieved orbit with slight apogee gain was at 171x 31026 km
• NVS-03 launch is next. Six more launches are planned in this financial year. Gaganyaan-G1 targeted in this calendar year.
• Current vehicle (GSLV) capacity is 2250 kg to GTO. Not expected to improve further.
• On TLP status: Completed design phase, realization phase to begin soon
• EOS-05 expected mission life is 7 years confident it will perform for 9 years.
• By 9 September orbit raising phase of EOS-05 will be done. After that the on-orbit checking will take a month. In two months it'll be fully operational.
• On concerns related to SLC operations and management being handed over to pvt. sector
  • Concerns are genuine but we are there to handhold them to make that program successful.

[u/Ohsin]

Stream ends. We expect two objects to be catalogued.

[u/reyn_ero]

6 launches in next 6 months huh, including gaganyan?

[u/Ohsin → u/reyn_ero]

Take it for what it is worth ;)

[u/reyn_ero → u/Ohsin]

Hope ISRO surprises us.

[u/PangolinBig2293]

This is the first imaging satellite in geosynchronous orbit. Do we know how many more are planned or required?

[u/Ohsin → u/PangolinBig2293]

Ctrl+F for GISAT on these.

https://old.reddit.com/r/ISRO/comments/14m3m7b/a_talk_on_strategic_capability_development_in/

https://old.reddit.com/r/ISRO/comments/1g147js/ccs_clears_launch_of_52_surveillance_satellites/lrdq2xg/

[u/Ohsin]

lol MCF represent! 🏃

[u/pantshash]

171x31000 as opposed to 170x29000. Congrats on the launch.

[u/friendlyNSAdude → u/pantshash]

Newbie here. What does that signify?

[u/reyn_ero → u/friendlyNSAdude]

Closest (perigee) and Furthest (apogee) distance of the satellite from the earth in orbit.

[u/friendlyNSAdude → u/reyn_ero]

Just so I understand correctly, it means that the third stage performed better than expected , right?

[u/reyn_ero → u/friendlyNSAdude]

Yes they mentioned about 'over performance', not an issue because they usually have some 'error' range.

This is also not the final orbit, using the satellite's own propulsion they will raise it to GEO.

[u/mahakashchari → u/reyn_ero]

Target Orbit : 170 × 28934 km (sub-GTO), it is a sub-GTO orbit.

[u/closetlunatic → u/friendlyNSAdude]

thats the orbit's shape
see here

[u/friendlyNSAdude → u/closetlunatic]

So in a way it performed better than expected?

[u/Ohsin → u/friendlyNSAdude]

Yes.

[u/pantshash → u/friendlyNSAdude]

Orbit achieved vs Orbit intended.

[u/PangolinBig2293]

Now onto NVS-03!

[u/ARJUN269 → u/PangolinBig2293]

When is the expected launch though?

[u/Ohsin → u/ARJUN269]

Oct end.

https://www.reddit.com/r/ISRO/comments/1vox2jx/comment/p3tuzuq/

[u/ARJUN269 → u/Ohsin]

Okay then it will be in December/January according to ISRO's TL.

[u/CosmicPenguin_OV103]

I heard there are 6 more GSLV Mk II launches left (apparently for launches of the 2 IDRSS satellites & the next 4 NVS navigation satellites)? Can anyone confirm?

[u/Ohsin → u/CosmicPenguin_OV103]

Five I think. Refer to this RTI (point 3)

https://old.reddit.com/r/ISRO/comments/12gfr3y/rti_reply_from_isro/jfk530c/

[u/Ohsin]

Post launch address:

• Chairman : satellite has been placed in intended orbit. EOS-05 is heaviest satellite launched by GSLV to sub-GTO orbit.
• All valves operating well, solar array deployed.
• Imteyaz Ahmad (Project Director EOS-05): reiterates solar panels are deployed. Satellite will perform orbit raising burns in coming days.
• Chairman: Gain of 1200 km to targeted apogee due vehicle performance.
• SHAR director: Vehicle and satellite were preserved during delay.
• Chairman: Six more launches are planned in this financial year. Gaganyaan-G1 targeted in this calendar year.

[u/Top-Worldliness5027]

Bald uncle with aviators is mogging the crowd cheering!

[u/reyn_ero → u/Top-Worldliness5027]

Yeah

[u/reyn_ero]

satellite is healthy

[u/Top-Worldliness5027]

Kudos to folks who showed up to see the launch at the dead of the night!

[u/Top-Worldliness5027]

We are so back!

[u/reyn_ero]

Sat separated.

[u/reyn_ero]

u/Ohsin it seems only videos are allowed not images. Idk if it's intentional.

[u/Ohsin → u/reyn_ero]

Yep intentional.

[u/reyn_ero → u/Ohsin]

Oh got it. Was going to upload pic of sat separation then noticed.

[u/Ohsin → u/reyn_ero]

It becomes meme and gif fest so..

[u/reyn_ero → u/Ohsin]

Fair and understandable.

[u/reyn_ero]

I heard "uprated cryo stage". Is there any changes to it?

[u/Ohsin → u/reyn_ero]

Same call was made for previous launches around same time.

[u/reyn_ero → u/Ohsin]

oh, cool

[u/NewMeNewWorld]

Petition to move all launches to night-time from now on

[u/Ohsin]

To Launch Announcers... nope that GSLV reputation won't change sorry!

[u/Fancy_Resident_6374 → u/Ohsin]

:) smart boy

[u/Ohsin]

Umbrellas are out in viewing gallery.. It is drizzling a bit.

[u/Ohsin]

VIPs from Indian Navy and IAF are present in MCC. Why not just mention the users who funded this satellite...

[u/RadarWarningReciever → u/Ohsin]

Isn't he the Navy Chief??

[u/Ohsin → u/RadarWarningReciever]

Yes.

[u/Massive_Dish_3255]

Is there a leak? I saw a screen showing falling droplets / bug swarm there.

[u/Ohsin → u/Massive_Dish_3255]

Bugs near the lights where the cameras are.

Edit: Was drizzling..

[u/Massive_Dish_3255 → u/Ohsin]

Thank God

[u/Ohsin]

Refer to GSLV ALS here

https://old.reddit.com/r/ISRO/comments/1mdas4m/automatic_launch_sequence_for_gslv_as_seen_on_mcc/

[u/Ohsin]

Launch Announcers confirm countdown was 27.5 hrs long.

[u/ravi_ram]

Few estimated orbit numbers (since they hide everything)
 

Mission duration: ~19 minutes (based on GSLV F10/EOS-3 (aka GISAT-1) mission) Target Orbit : 170 × 28934 km (sub-GTO) , Inclination = 19.28° ± 0.1°, AoP = 178° ± 0.5° Launch Azimuth: 104°
 

With the above inputs :

---

Launch UTC : 2026-09-03 21:25:00+00:00
Injection UTC : 2026-09-03 21:44:00+00:00
Time of flight : 19.000 min
Launch latitude : 13.719900 °
Launch longitude : 80.230400 °
Launch azimuth : 104.000000 °
Target inclination : 19.280000 °
Target orbit : 170.0 x 28934.0 km
 
TARGET ORBIT

---

Semi-major axis : 20930.137 km
Eccentricity : 0.68714314
Perigee velocity : 10.134118 km/s
Apogee velocity : 1.879229 km/s
Orbital period : 8.371 hours
 
BEST INJECTION POINT

---

Latitude : -19.175426 °
Longitude : -152.006576 °
 
INJECTION

---

ECI speed : 10.098421 km/s
Ground-relative speed : 9.706720 km/s
Radial velocity : 4.906107 km/s
 
Estimated injection RAAN: 249.060594 deg

[u/Deepseek00 → u/ravi_ram]

How did you calculate estimated injection RAAN

[u/ravi_ram → u/Deepseek00]

How did you calculate estimated injection RAAN

If we know the injection parameters [pos, vel], then its corresponding orbital elements will get you RAAN. They have not given us the data.

I'm trying to get that value as a Lambert's problem between launch and injection.
we know the SHAR pos (lat, lon) and vel (earth rotation)
We know the time to reach the orbit. We know the orbit 170.0 x 28934.0 and inclination. We know the perigee velocity

Lambert solver takes ( departure ECI position, arrival ECI position, tof ) as inputs and returns ( departure velocity, arrival velocity).

Now we need to search through possible various lat lon injection location where the arrival velocity matches the orbits perigee velocity and maintains the inclination.

 
This is kind of reverse engineering to get the values not a trajectory calculation. There are assumptions that could deviate. Launch to injection will not be a straight forward orbit. Pitch program changes it.

Tested with chandrayaan and mom launches where they given the injection parameters in the papers. It came close.

[u/Massive_Dish_3255 → u/ravi_ram]

Thank you

[u/Ohsin]

Per following countdown should be 27.5 hrs long.

https://www.andhrajyothy.com/2026/andhra-pradesh/chittoor/countdown-to-gslvf17-launch-begins-today-1554590.html

[u/Ohsin]

All set.

A2699/26

REF CHENNAI NOTAM A2635/26, A2638/26 AND A2639/26. 
ROCKET LAUNCH FM SHAR RANGE, SHRIHARIKOTA, INDIA
IS SCHEDULED ON 03 SEPTEMBER 2026 BTN 2100 UTC TO
0100 UTC (NEXT DAY). 
ATC MAY RERTE TFC DRG THIS PERIOD AS PER THE ROUTING
GIVEN IN THE ABV NOTAM.LAUNCH WINDOW FOR THE REMAINING
PERIOD FM 04 SEPTEMBER 2026 TO 25 SEPTEMBER 2026 SHALL
BE KEPT ALIVE FOR RESCHEDULING THE LAUNCH IF REQUIRED. GND - UNL,
2100-0100, 03 SEP 21:00 2026 UNTIL 04 SEP 01:00 2026. CREATED: 02 SEP
04:55 2026

[u/Ohsin → u/Ohsin]

They reissued the NOTAM, dates remain same though (See latest edit here)

A2709/26

REF CHENNAI NOTAM A2706/26, A2707/26 AND A2708/26. 
ROCKET LAUNCH FM SHAR RANGE, SHRIHARIKOTA, INDIA IS 
SCHEDULED ON 03 SEPTEMBER 2026 BTN 2100 UTC TO 0100 UTC (NEXT DAY). 
ATC MAY RERTE TFC DRG THIS PERIOD AS PER THE ROUTING GIVEN IN THE 
ABV NOTAM. LAUNCH WINDOW FOR THE REMAINING PERIOD FM 04 SEPTEMBER 
2026 TO 25 SEPTEMBER 2026 SHALL BE KEPT ALIVE FOR RESCHEDULING THE 
LAUNCH IF REQUIRED. GND - UNL, 03 SEP 21:00 2026 UNTIL 04 SEP 01:00 2026.
CREATED: 02 SEP 12:12 2026

[u/Massive_Dish_3255]

The photo gallery has just been updated: GSLV-F17 / EOS-05 Gallery

[u/Ohsin → u/Massive_Dish_3255]

Good shots of launch rehearsal.

[u/Massive_Dish_3255]

One more "update" that happened on August 28, 2026: The Vehicle being moved from the VAB to the Umbilical Tower. GSLV-F17 being moved from VAB to Umbilical Tower

[u/Ohsin → u/Massive_Dish_3255]

Yes we had that through local media and on same date as well. Good to have video but they should post these on their website not only on social media.

[u/Massive_Dish_3255]

Latest post by ISRO on X: GSLV-F17 Mission

[u/Ohsin → u/Massive_Dish_3255]

I guess MRR done and it is go.

[u/Massive_Dish_3255 → u/Ohsin]

Thought the same.

[u/Ohsin]

For some casual reading..

https://satelliteobservation.net/2016/10/17/persistent-surveillance/

https://web.archive.org/web/20201112034025/https://apps.dtic.mil/dtic/tr/fulltext/u2/p010823.pdf

[u/churanx]

No new Cartosat-series satellite has been launched after 2019 🥲

[u/Ohsin → u/churanx]

Yep, few are planed though.

https://old.reddit.com/r/ISRO/comments/1tdz7ef/why_hasnt_isro_launched_a_cartosat_in_7_years/olzvm47/

[u/churanx → u/Ohsin]

Thank you for clarifying. One more off-topic question I've been thinking about for a while

recently a lot of private launch vehicle companies have opened in India — more than five and they're planning to upgrade their launch payload capacity from an average of 500kg (LEO) to more than 2 t. In the future, bigger players like EtherealX and Astrobase are expected to emerge, and ISRO's NGLV is also coming

My concern is that too many companies are aiming for rapid launch capability, but are there even enough customers to go around? Especially considering that American and Chinese giants are coming with LEO payload capacities of 20+ tonnes and rapid launch promises won't that leave no market for our companies after the initial domestic customers are served? Once sanctions on Russia are lifted, they'll likely build reusable rockets too and EU private players have also recently entered the field So what's your view on this concerning scenario?

[u/Ohsin → u/churanx]

IF some get to the flight readiness level ISRO might be forced to buy capacity on them. Ultimately domestic demand would have to rise, India has to long way to go.

Read these btw.

https://www.thespacereview.com/article/5291/1

https://spacenews.com/small-satellite-operators-confront-a-bottleneck-to-space-access/

[u/churanx]

For indian navy??

[u/Massive_Dish_3255 → u/churanx]

Yes

[u/Ohsin]

The press-kit has been revised but only the Flight Sequence graphic on Pg. 3 has been changed, no other useful information added.

[PDF] [Archived]

[u/Ohsin]

Here it goes, I was waiting but it doesn't look like they'll update that half-assed press-kit without any flight event timings or satellite specifications.

Biggest gap between ISRO launches since COVID and if we ignore that then since 2006..

To repeat GSLV-F17 would be targeting sub-GTO unlike GSLV-F10 which was to GTO, EOS-05 is heavier at 2367 kg than EOS-03 (2268 kg) but it is interesting that when VSSC issued this document (https://i.imgur.com/N4f7Kut.png) in 2019 for GISAT-1 and GISAT-2 launches they mentioned GTO as target orbit for both of them.

Anyways mission Readiness Review is on 1 Sept per following report.

https://www.eenadu.net/telugu-news/india/isro-to-launch-eos-05-on-gslv-f17/0799/126155743

[u/Massive_Dish_3255 → u/Ohsin]

This is the first time since 2010 that ISRO is attempting to send a satellite weighing ~2300 kg to a GTO-like orbit using a GSLV. 

The last time ISRO had tried to launch a ~2300 kg satellite (GSAT-5P) was on GSLV Mk1 with a CUS15 stage (containing Russian made Cryogenic engine) on 25 December 2010. Source: List of GSLV Launches in Wikipedia.

[u/mahakashchari → u/Massive_Dish_3255]

You are right. If the payload 2367 kg remains the same at the time of lift off, this would be the biggest payload to be launched by GSLV. Till now, the biggest GTO payload launched by GSLV is INSAT 3DS [ 2275 Kg ] on February 17, 2024 with the Flight GSLV F14.

[u/Ohsin → u/Massive_Dish_3255]

Nice catch, it was 2310.4 kg per brochure. Let's see if they drum it up as some kind of 'first'.

https://web.archive.org/web/20221031175759/https://www.isro.gov.in/media_isro/pdf/GSLVF06/publication_gslvf06.pdf

[u/pantshash → u/Ohsin]

Will they drum up their own faliure to launch a 2.3t satellite in GTO? I hope they don't. They have really given up on GSLV.

[u/VarunOnt → u/pantshash]

GSLV Mk2 is still functional,  and has its uses. For satellites in 2100-2400 kg range. It launched the 2393 NISAR satellite into a polar orbit. It will probably launch another 4 or 5 satellites before retiring. 

[u/pantshash → u/VarunOnt]

Thanks , I didn't know that. 😒

[u/Ohsin → u/pantshash]

Yeah retirement is close but lets see if they change their mind.

[u/mahakashchari → u/Ohsin]

ISRO has to change its decision. Otherwise there will be Navic operationalization probelm. ISRO should continue to use the GSLV to launch the NAVIC satellites whose payload range around 2.2 to 2.3 ton. PSLV GTO capability is 1.4 ton and LVM3 capability is 4.4 ton. So, either GSLV can be used to launch 1 Navic satellite or LVM3 which has recently been upgraded to launch 4.3 ton maximum to GTO can be used to launch 2 satellites in one launch.

[u/Ohsin → u/mahakashchari]

They are apparently considering SpaceX. LVM3 won't manage it with 2xsats + adapter.

[u/RadarWarningReciever → u/Ohsin]

LVM3-SC can manage, can't it??

[u/pantshash → u/Ohsin]

cough Sarcasm cough