ISRO General News and Updates

[Swesh]

Will the PSLV XPoSAT mission carry any secondary payloads/ satellites. 455 kg ( weight of Xposat ) seems rather small for the PSLV

That means many experimental payload

 

[Varoon2]

More info, brochure for PSLV XPoSAT mission

XPoSat

 

[TopWatcher]

That means many experimental payload

 

[FalconSlayers]

From: @Karthi

 

[TopWatcher]

View attachment 234155
From: @Karthi

Hw nuclear will generate propulsion??

 

[Abhijat]

Isro to launch 50 satellites in 5 years to boost India's intelligence-gathering capabilities; Aditya-L1 set to reach Lagrange Point on January 6: Isro chief S Somnath - Times of India

Indian Space Research Organisation (Isro) plans to launch 50 satellites in the next five years for geo-intelligence gathering. These satellites will be deployed in various orbits to monitor troop movements and capture images of extensive areas. The goal is to enhance India's geo-intelligence...

m.timesofindia.com

Isro To Launch 50 Satellites In 5 Years To Boost India's Intelligence-Gathering Capabilities

The goal is to mitigate threats to the country by deploying a diverse array of satellites, spanning from geostationary equatorial orbit (GEO) to lower earth orbit (LEO) and very low earth orbit. This multi-orbit approach allows for critical assessment of different situations, incorporating optical, synthetic aperture radar (SAR), thermal, and other technologies.

 

[Swesh]

1.it seems we will have RISAT-3 series of satellites, I am guessing its resolution might be 10cm
2. GISAT-4 satellite, with 5m resolution

 

[Swesh]

RISAT-3S has Unfurlable antenna like Anvesha & NISAR

 

[Varoon2]

Both Economic Times and Wikipedia suggest that Shukrayaan may be launched this coming year. ET is more directly asserting that it will be 2024, whereas Wiki mentions that there are 2 launch windows, one in 2024, the next in 2031.

 

[Swesh]

Launch of PSLV-C58/XPoSat Mission from Satish Dhawan Space Centre (SDSC) SHAR, Sriharikota

XPoSat (X-ray Polarimeter Satellite) is India’s first dedicated polarimetry mission to study various dynamics of bright astronomical X-ray sources in extreme...

www.youtube.com

Live stream for PSLV c58
xposat, POEM 3

 

[raju1982]

View attachment 234329
1.it seems we will have RISAT-3 series of satellites, I am guessing its resolution might be 10cm
2. GISAT-4 satellite, with 5m resolution

Extremely important. Too many astro science missions these days. Good to hear about milsats.

 

[Swesh]

Extremely important. Too many astro science missions these days. Good to hear about milsats.

That's how I think

 

[Varoon2]

Nice trailer video for XPoSat mission

PSLV-C58 / XPoSat Mission - Teaser Video

 

[Swesh]

ISRO, BARC join hands to develop nuclear engines for rockets

ISRO and BARC are developing nuclear-powered engine, RTGs, to power satellites on deep space missions. RTGs use radioactive materials to generate heat, which is then converted to electricity to charge batteries and provide motive force. 5W RTG is the target. US spacecrafts have used RTGs in the...

www.thehindubusinessline.com

Article is wrong RTG are not capable to propell rocket into space it can only enhance life of spacecraft. I resist quoting news article long ago it makes people look like fool just like newswalas. RTG is never used in engine its used in satellite to generate renewable energy which enhances sats lifetime we tested RTG on propulsion module to keep it last long than other modules

 

[Swesh]

?

http://large.stanford.edu/courses/2017/ph241/villalpando1/http://large.stanford.edu/courses/2017/ph241/villalpando1/

Mission design study of an RTG powered, ion engine equipped interstellar spacecraft

This research explores a variety of mission and system architectures for an unmanned Interstellar Precursor Mission (IPM) spacecraft with a Radioisotope Thermoelectric Generator (RTG) powered Ion Engine using Xenon propellant, traveling on a (direct) ballistic escape trajectory to the...

ui.adsabs.harvard.edu

And spacecraft here means astronomical satellite not rockets propeller it can't generate required thrust

 

[Swesh]

Kindly read up more...

View attachment 234525

To Deep Space and Beyond: Nuclear Electric Rockets

Bhai I read whole article none of it mentioned nuclear rocket can be used to escape earth atmosphere it's still an idea no TD happened so far even by NASA

 

[Swesh]

Kindly read up more...

View attachment 234525

To Deep Space and Beyond: Nuclear Electric Rockets

Search this on Google
can nuclear rocket be used to escape earth atmosphere

 

[Swesh]

Kindly read up more...

View attachment 234525

To Deep Space and Beyond: Nuclear Electric Rockets

To Deep Space and Beyond: Nuclear Electric Rockets
Travis Lanham
February 14, 2017
Submitted as coursework for PH241, Stanford University, Winter 2017
Introduction

Fig. 1: Nuclear Thermal Rocket engine. (Source: Wikimedia Commons)
The cosmos has long captured human imagination as a last, incomprehensibly vast, frontier for exploration. Since the first V2 rockets of WWII, to the surprise launch of Sputnik that kicked off the space race, mankind and it's machines continue to push further into space, relying on nuclear energy to power them for decades after they have left the surface of the Earth.

Developments in nuclear power enabled the space age and are vital to future missions that look to travel far beyond the solar energy of the Sun. Two nuclear technologies in particular, radioisotope thermoelectric generators and fission reactors, have played important roles in space exploration thus far and are instrumental to interstellar aspirations.

History
Nuclear energy has played an essential role in space development and exploration since the first nuclear powered spacecraft, the navigational satellite Transit 4A, was launched in 1961. It used a radioisotope thermoelectric generator (RTG) to convert heat from the decay of Pu-238 to heat energy using the Seebeck effect. [1] Essentially the RTGs work by converting the natural decay of radioactive elements to electricity. Since the launch of Transit 4A, RTGs have powered numerous satellites as well the Spirit and Opportunity Mars rovers. In 2012, the probe Voyager 1 became the first human-made artifact to leave the solar system, powered by a set of radioisotope thermoelectric generators to provide electricity to accelerate hydrazine for propulsion. [2] With no moving parts, RTGs require no maintenance and only minimal shielding, making them ubiquitous in satellites, rovers, and probes, as well as human missions including the Apollo lunar landing program.

Fission in Space
In addition to RTGs, fission reactors have been studied and developed for applications that require more power than is feasible from RTGs. Development of fission reactors for space started with a simplified fission reactor that would be used to provide electrical power for satellites; in 1965, the United States launched the first space reactor, called SNAP-10A, which functioned for 43 days before a voltage regulator (not part of the reactor) failed. Though the United States abandoned the concept after SNAP-10A, the Soviet Union launched over 30 reactors to power surveillance satellites. [1]

Nuclear Thermal Rocket
In addition to providing electricity for electronic satellite systems, space fission reactors have also been developed to provide energy to replace chemical combustion propulsion systems. In the nuclear systems, the fission reaction heats a liquid hydrogen propellent to a gaseous state which is then ejected through a cone to give thrust, as seen in Fig. 1. The reactors can also be configured to as a dual mode system to heat propellent as well as generate electricity that can be used to power spacecraft electrical systems for crew habitation. [3]

The United States built and tested 23 nuclear thermal fission systems for testing as part of the NERVA program in the 1960s. [4] Interest in the technology has renewed as it is seen as the best way to power a human mission to mars. NASA uses a nuclear thermal rocket in its mars reference mission to heat liquid hydrogen for propulsion, yielding a thrust capability that is twice that of conventional liquid oxygen chemical rockets. [5]

Conclusions
Nuclear energy has been instrumental to humankind's space exploration since its beginning and will play an even larger role in future missions that look to venture beyond our solar system to new stars and worlds. RTGs will continue to be important components for low power needs that need long-lasting, durable stores of energy. Nuclear Thermal Rockets are the best available engine systems for interplanetary travel at higher speeds.

Investment in nuclear technology development is essential to the next generation of spacecraft and the key to unlocking the potential for interstellar travel. For the foreseeable future, missions will limited by the amount of propellent they can carry, but investments in nuclear could lead to new discoveries that enable more ambitious spacecraft that have been proposed to explore deep space and beyond.

© Travis Lanham. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.

References
[1] S. Aftergood et al., "Nuclear Power in Space," Sci. Am. 264, No. 6, 42 (June 1991).

[2] D. Gurnett et al., "In Situ Observations of Interstellar Plasma with Voyager 1," Science 341, 1489 (2013).

[3] S.K. Borowki et al., "Nuclear Thermal Rocket/Vehicle Design Options for Future NASA Missions to the Moon and Mars," U.S. National Aeronautics and Space Administration, NASA TM-107017, September 1993.

[4] A. Wendorff, "Potential Testing and Space Applications of Nuclear Thermal Rockets," Physics 241, Stanford University, Winter 2014.

[5] B. Drake, "Human Exploration of Mars Design Reference Architecture 5.0," U.S. National Aeronautics and Space Administration, NASA-SP-2009-566, July 2009.

 

[Swesh]

Spacecraft/Satellite thrusters, proplusion systems and retro thrusters etc.

Timeline of LPSC

defenceforumindia.com

 

[Swesh]

I guess we both are having a comprehension problem here