EOS-09

EOS-09

Names	Radar Imaging Satellite-1B
Mission type	Imaging radar
Operator	ISRO
Website	ISRO PSLV-C61 / EOS-09 Mission
Mission duration	5 years (planned) Failed to orbit
Spacecraft properties
Spacecraft	EOS-09
Manufacturer	ISRO
Start of mission
Launch date	18 May 2025, 05:59 IST
Rocket	PSLV-C61
Launch site	Satish Dhawan Space Centre, First Launch Pad (FLP)
Contractor	ISRO
Orbital parameters
Reference system	Geocentric orbit[1]
Regime	Sun-synchronous orbit
Perigee altitude	526.7 km (327.3 mi) (planned)
Apogee altitude	543.4 km (337.7 mi) (planned)
Inclination	97.6°
Period	95.2 minutes
Instruments
Synthetic Aperture Radar (C-band) (SAR-C)
Earth observation satellites series

EOS-09 or Earth Observation Satellite-09 (formerly known as RISAT-1B) was an Indian Space Research Organisation radar imaging satellite designed to provide continuous and reliable remote sensing data for operational applications across various sectors.^[2] It was intended to be a follow on to RISAT-1 satellite with similar configuration. The satellite was developed by the ISRO and was the seventh in the series of RISAT satellites.^[3][4][5]

Satellite description

Synthetic aperture radar can be used for Earth observation irrespective of the light and weather conditions of the area being imaged.^[6] It complements/supplements data from Resourcesat, Cartosat and RISAT-2B Series.^[7] The satellite carries a C-band synthetic-aperture radar (SAR) and has a liftoff mass of 1,710 kg (3,770 lb).^[1] The EOS-09 orbit is expected to be in a polar and Sun-synchronous orbit at 05:30 AM LTDN, at approximate altitude of 529 km.^[8]

Launch Failure

The PSLV-C61 mission launched EOS-9 on 18 May 2025 at 5:59 AM IST. The first and second stages performed nominally, however, the third stage experienced an anomaly which resulted in loss of mission. ISRO is investigating the failure.^[9][10]

See also

• PSLV-C61
• List of Indian satellites
• ISRO
• RISAT
• PSLV

References

1. "PSLV-C52/EOS-04 Mission". ISRO. Archived from the original on 9 February 2022. Retrieved 9 February 2022.
2. "EOS-09". ISRO. Archived from the original on 16 May 2025. Retrieved 18 May 2025.
3. Krebs, Gunter (8 October 2021). "RISAT 1, 1A, 1B (EOS 04)". Gunter's Space Page. Archived from the original on 26 December 2021. Retrieved 26 December 2021.
4. "Unstarred Question No. 4702" (PDF). Lok Sabha. National Informatics Centre. 29 March 2023. Archived from the original (PDF) on 29 March 2023. Retrieved 12 April 2023.
5. "Mission Summary - RISAT-1B". CEOS. 2021. Archived from the original on 26 December 2021. Retrieved 26 December 2021.
6. Raj, N. Gopal (25 April 2012). "RISAT-1's radar can see through clouds and work in darkness". The Hindu. Chennai, India.
7. "PSLV-C52/EOS-04 Brochure - ISRO". www.isro.gov.in. Archived from the original on 9 February 2022. Retrieved 17 February 2022.
8. Reddy, O.V. Raghav (3 February 2016). "Future Earth Observation Missions of ISRO, NRSC User Interaction Meet 2016" (PDF). Archived from the original (PDF) on 3 February 2017.
9. "EOS-09 mission unsuccessful, will begin technical analysis, says ISRO chief - The Economic Times". m.economictimes.com. Retrieved 18 May 2025.
10. ISRO Official (17 May 2025). ISRO’s 101st Launch | PSLV-C61 / EOS-09 | 18 May 2025. Retrieved 18 May 2025 – via YouTube.