What's new

China Space Military:Recon, Satcom, Navi, ASAT/BMD, Orbital Vehicle, SLV, etc.

Did you study in NIT Trichy and before that took IIT coaching in Kota?

I did my btech in control engineering at NIT trichy and pursuing direct PhD at IIT madras(flight dynamics and control).
Coaching- narayana Hyderabad
 
Last edited:
China's Jilin-1 commercial satellite has a resolution of 0.72 meter

China launches first commercial-use Earth imaging satellite | GBTimes

O45eEI2.jpg
 
China launches cube satellites for civil aircraft tracking
Source:Xinhua Published: 2015-10-7 14:17:52

China has successfully launched three cube satellites (CubeSats), which are expected to help track civil aircraft and ships and avoid tragedies like missing flight MH370.

The three CubeSats in a mission coded STU-2 were launched on Sept. 25 and have entered their designed orbit, according to the mission's chief designer, Wu Shufan.

The three spacecraft are equipped with polar region observation cameras as well as automatic identification system (AIS) receivers for information from ships and automatic dependent surveillance-broadcast (ADS-B) receivers for messages sent from civil flights.

The ADS-B system was developed to be installed on civil aircraft and transmit readings of the flight's position, height, speed, direction and other information automatically every second to receivers on the ground or in the air. Currently more than 70 percent of aircraft have such systems installed.

As of the evening of Sept. 28, the STU-2 CubeSats had collected hundreds of thousands of ADS-B messages from more than 12,400 aircraft flying within receiving range.

The paths and traffic flow of civil flights within the satellites' monitoring area may be collected in real time.

"If there are enough satellites in orbit to cover a region wide enough, a specific flight could be tracked and that may help with spotting, search and rescue in cases like Malaysia Airlines flight MH370," Wu said.

CubeSats may also be used to provide information support for ship operations such as the Chinese icebreaker Xuelong (Snow Dragon) in polar regions.

Wu said the STU-2 mission, the first of its kind by China, is a step in the country's satellite network development for civil aircraft and ship monitoring.

He also called for more international cooperation to expand the network's reach.

Like a Rubik's cube, a CubeSat is a satellite composed of smaller cubic units. Depending on its different uses, a CubeSat may contain two, three or more such units.

Compared with other integral satellites, cube spacecraft are generally smaller, lighter and much more economical in development and production costs.

Wu said the three STU-2 CubeSats weigh only 6.8 kilograms in total.

****************************************************************************************

Launch of Jilin-1 commercial satellite at 7th October 2015, 12:13 Beijing Time.


1444196890947.jpg


1444196936393.jpg


1444196953129.jpg


1444196967564.jpg


1444196978944.jpg
 
China launches Jilin-1 mission via Long March 2D | NASASpaceFlight.com

China launched four satellites to provide photographs to commercial clients while helping with harvest assessment, geological disaster prevention and resource surveys. The launch of the Jilin-1 mission took place at 04:13 UTC on Wednesday, using a Long March-2D launch vehicle from the 603 Launch Pad at the Jiuquan Satellite Launch Center’s LC43.

Chinese Launch:

The Jilin-1 mission was developed on the China’s Jilin Province and is the country’s first self-developed remote sensing satellite for commercial use.

Jilin-1 consists of four satellites, one for high-definition images, one for testing new space technology and another two for video.

Data will be provided to commercial clients to help them forecast and mitigate geological disasters, as well as shorten the time scale for the exploration of natural resources.

2015-10-06-235504-350x238.jpg
The satellites were developed by the Chang Guang Satellite Technology Co., Ltd under the Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences.

Jilin, one of the country’s oldest industrial bases, is developing its satellite industry as a new economic drive. The province plans to launch 60 satellites by 2020 and 138 by 2030.

The first phase will see the launch of the first four Jilin-1 satellites. Between 2016 and 2019 there are plans to have 16 satellites in orbit, completing a remote sensing network that will cover the entire globe and will be capable of a three to four hours update in the data provided.


From 2020, the plans point to a 60 satellite orbital constellation capable of a 30 minutes update in the data provided.


From 2030 the Jilin constellation will have 138 satellites in orbit, forming a all-day, all-weather, full spectrum acquisition segment data and a capability of observing any global arbitrary point with a 10 minutes revisit capability, providing the world’s highest spatial resolution and time resolution space information products.


The four satellites are Jilin-1, Lingqiao-A, Lingqiao-B and LQSat.

Jilin 1 is a 420 kg high-definition optical satellite with a 0.72 m resolution pan-chromatic camera and 4 m resolution multi-spectral camera.

It is equipped with three deployable solar panels for power generation that will be stored in internal batteries. The satellite will operate on a 656 km sun synchronous orbit.

2015-10-07-054204-350x267.jpg
The Lingqiao-A and Lingqiao-B satellites are designed to capture videos with a 4K ultra-clear video resolution of 1.13 meters m on 4.3 x 2.4 km swaths. Weighing 95 kg each, its dimensions are 1.1 meter diameter and 1.2 length.

The satellites are equipped with body mounted solar panels. The satellites will operate on a 656 km sun synchronous orbit.

LQSat is a micro-satellite for technology demonstration designed by CIOMP. Its main payload is a camera with 2 m resolution.

LQSat is equipped with a fixed solar array for power generation. Satellite dimensions are 0.40 x 0.40 x 0.60 m and a mass of about 54 kg. The lifetime of LQSat is about 1 year. UHF downlink with 25 wpm CW and 4k8 CSP packet data using MSK at 27dBm, and also a 2.4GHz downlink at 30dBm using 1Mbps QPSK.

Launch Vehicle and Launch Site:

This launch was the 226th Chinese orbital launch and the 213th launch of the Long March launch vehicle family. It was also the 80th orbital launch from the Jiuquan Satellite launch Center, the 3rd launch from this space center in 2015 and the 10th orbital launch for China this year.

2014-11-20-11_06_16-Yaogan-Weixing-24-Long-March-2D-JSLC-November-20-2014-350x254.jpg
The Chang Zheng-2D launch vehicle is a two-stage rocket developed by the Shanghai Academy of Spaceflight Technology. With storable propellants is mainly used to launch a variety of low earth orbit satellites.

The development of CZ-2D was started in February 1990. From 2002, to meet the demand of SSO satellites, the payload fairing of 3350mm in diameter and attitude control engine for second stage have been successfully developed; and the discharge of remaining propellant and de-orbit of the second stage have been realized.

This launcher is mainly used for launching LEO and SSO satellites. It is characterized with high reliability, wide application and mature technology.

2015-10-07-030511-350x232.jpg
The CZ-2D can launch a 1,300 kg cargo in a 645 km SSO. The rocket is 41.056m long and the first, second stages and payload fairing are all 3.35m in diameter.

Its first stage is the same of the CZ-4 Chang Zheng-4. The second stage is based on CZ-4 second stage with an improved equipment bay. Lift-off mass is 232,250 kg, total length 41,056 meters, diameter 3.35 meters and fairing length 6.983 meters. At launch it develops 2961.6kN engine thrust.

The first stage has a 27.910 meter length with a 3.35 meter diameter, consuming 183,200 kg of N2O4 / UDMH (launch mass of the first stage is 192,700 kg). Equipped with a YF-21C engine capable of a ground thrust of 2,961.6 kN and a ground specific impulse of 2,550 m/s. Burn time is 170 seconds.

2015-10-07-030546-350x249.jpg
The second stage has a 10.9 meter length with a 3.35 meter diameter, launch mass of 39,550 kg and consuming 45,550 kg of N2O4 / UDMH. Equipped with a YF-24C cluster engine with a main engine vacuum thrust of 742.04 kN and a vernier engine with a vacuum thrust of 47.1 kN (specific impulses of 2,942 m/s and 2,834 m/s, respectively).

The CZ-2D can use two types of fairings depending on the cargo. Type A fairing has a 2.90 meters diameter (total launch vehicle length is 37.728 meters) and Type B fairing with a diameter of 3.35 meters – total launch vehicle length is 41.056 meters.

The first launch of the CZ-2D was on August 9th, 1992 from the Jiuquan Satellite Launch Center orbiting the Fanhui Shei Weixing FSW-2-1 (22072 1992-051A) recoverable satellite.

The Jiuquan Satellite Launch Center, in Ejin-Banner – a county in Alashan League of the Inner Mongolia Autonomous Region – was the first Chinese satellite launch center and is also known as the Shuang Cheng Tze launch center.

2014-09-28-10_08_40-Shi-Jian-11-07-CZ-2C-JSLC-05_28UTC-September-28-2014-350x239.jpg
The site includes a Technical Centre, two Launch Complexes, Mission Command and Control Centre, Launch Control Centre, propellant fuelling systems, tracking and communication systems, gas supply systems, weather forecast systems, and logistic support systems.

Jiuquan was originally used to launch scientific and recoverable satellites into medium or low earth orbits at high inclinations. It is also the place from where all the Chinese manned missions are launched.

The LC-43 launch complex, also known by South Launch Site (SLS) is equipped with two launch pads: 921 and 603. Launch pad 921 is used for the manned program for the launch of the Chang Zheng-2F launch vehicle (Shenzhou and Tiangong). The 603 launch pad is used for unmanned orbital launches by the Chang Zheng-2C, Chang Zheng-2D and Chang Zheng-4C launch vehicles.

Other launch zones at the launch site are used for launching the Kuaizhou and the CZ-11 Chang Zheng-11 solid propellant launch vehicles.

The first orbital launch took place on April 24, 1970 when the CZ-1 Chang Zheng-1 rocket launched the first Chinese satellite, the Dongfanghong-1 (04382 1970-034A).
 
Instead of arguing, can you please give me some answers here?


What is the minimum resolution required to detect a 300m long object clearly?

Can someone do a simple experiment:


Take many images of resolution ranging from 5 m all the way to 50 m and try to see what 300 m in that image looks like.
 
Guys ... why do I have that strange feeling that a few are here only to ask strange questions or answering without an argument like in most posts ... could You simply explain ?
 
Guys ... why do I have that strange feeling that a few are here only to ask strange questions or answering without an argument like in most posts ... could You simply explain ?

If you are referring to me, I have asked a very legitimate question, because GF 4 is China's first Earth Observation Satellite, that will be Geostationery.

Being Geostationery gives it around the clock coverage of a certain geographical area, here it will be China's naval littorals.

It will be game changing if the satellite can reliably detect ACs.
 
Back
Top Bottom