How to Deflect an Asteroid with Today’s Technology

Artist concept of a space tug. Credit: NASA

Apollo 9 astronaut Rusty Schweickart is among an international group of people championing the need for the human race to prepare for what will certainly happen one day: an asteroid threat to Earth. In an article on Universe Today published yesterday, Schweickart said the technology is available today to send a mission to an asteroid in an attempt to move it, or change its orbit so that an asteroid that threatens to hit Earth will pass by harmlessly. What would such a mission entail?

In a phone interview, Schweickart described two types of “deflection campaigns” for a threatening asteroid: a kinetic impact would roughly “push” the asteroid into a different orbit, and a gravity tractor would “tug slowly” on the asteroid to precisely “trim” the resultant change course by using nothing more than the gravitational attraction between the two bodies. Together these two methods comprise a deflection campaign.

Artist Impression of Deep Impact - Credit: NASA

ISRO Launch Vehicles - Geosynchronous Satellite Launch Vehicle Mark III

The GSLV-III or Geosynchronous Satellite Launch Vehicle Mark III , is a launch vehicle currently under development by the Indian Space Research Organization. GSLV Mk III is conceived and designed to make ISRO fully self reliant in launching heavier communication satellites of INSAT-4 class, which weigh 4500 to 5000  kg. It would also enhance the capability of the country to be a competitive player in the multimillion dollar commercial launch market. The vehicle envisages multi-mission launch capability  for GTO, LEO, Polar and intermediate circular orbits. 

GSLV-Mk III is designed to be a three stage vehicle, with 42.4 m tall with a lift off weight of 630 tonnes. First stage comprises two identical S200 Large Solid Booster (LSB) with 200 tonne solid propellant, that are strapped on to the second stage, the L110 re-startable liquid stage. The third stage is the C25 LOX/LH2 cryo stage. The large payload fairing measures 5 m in diameter and can accommodate a payload volume of 100 cu m. The development work on Mk III is progressing as per schedule for a launch in 2012.

ISRO Launch Vehicles - Geosynchronous Satellite Launch Vehicle(GSLV) - Mark I&II

Geosynchronous Satellite Launch Vehicle(GSLV)-Mark I&II ,is capable of placing INSAT–II class of satellites (2000 – 2,500 kg) into Geosynchronous Transfer Orbit (GTO).  GSLV is a three stage vehicle GSLV is 49 m tall, with 414 t lift off weight. It has a maximum diameter of 3.4 m at the payload fairing. First stage comprises S125 solid booster with four liquid (L40) strap-ons.  Second stage (GS2) is liquid engine and the third stage (GS3) is a cryo stage.   The vehicle develops a lift off thrust  of 6573 kn.  

The first flight of GSLV took place from SHAR on April 18, 2001 by launching 1540 kg GSAT-1. It was followed by six more launches , GSLV-D2 on May 8, 2003 (GSAT-2  1825 kg), GSLV-F01 on September 20, 2004 (EDUSAT 1950 kg), GSLV-F02 on July 10, 2006, GSLV-F04 on September 2, 2007 (INSAT-4CR   2130 kg), GSLV-D3 on April 15, 2010 and GSLV-F06 on December 25, 2010.

GSLV Milestones 

GSLV-F06 launched GSAT-5P on December 25, 2010 (Unsuccessful) GSLV-D3 launched GSAT-4 on April 15, 2010 (Unsuccessful) GSLV-F04 launched INSAT-4CR on September 2, 2007 (Successful) GSLV-F02 launched INSAT-4C on July 10, 2006 (Unsuccessful) GSLV-F01 launched EDUSAT(GSAT-3) on September 20, 2004 (Successful) GSLV-D2 launched GSAT-2 on May 8, 2003 (Successful) GSLV-D1 launched GSAT-1 on April 18, 2001 (Successful)

ISRO Launch Vehicles - Polar Satellite Launch Vehicle (PSLV)

The Polar Satellite Launch Vehicle,usually known by its abbreviation PSLV is the first operational launch vehicle of ISRO. PSLV is capable of launching 1600 kg satellites in 620 km sun-synchronous polar orbit and 1050 kg satellite in geo-synchronous transfer orbit. In the standard configuration, it measures 44.4 m tall, with a lift off weight of 295 tonnes. PSLV has four stages using solid and liquid propulsion systems alternately. The first stage is one of the largest solid propellant boosters in the world and carries 139 tonnes of propellant. A cluster of six strap-ons attached to the first stage motor, four of which are ignited on the ground and two are air-lit. 

The reliability rate of PSLV has been superb. There had been 20 continuously successful flights of PSLV, till April 2012. 

With its variant configurations, PSLV has proved its multi-payload, multi-mission capability in a single launch and its geosynchronous launch capability. In the Chandrayaan-mission, another variant of PSLV with an extended version of strap-on motors, PSOM-XL, the payload haul was enhanced to 1750 kg in 620 km SSPO. PSLV has rightfully earned the status of workhorse launch vehicle of ISRO.

PSLV Milestones  

	PSLV-C19 launched RISAT-1 on April 26, 2012 (Successful)
	PSLV-C18 launched Megha-Tropiques, SRMSat, VesselSat-1 and Jugnu on October 12, 2011 (Successful)
	PSLV-C17 launched GSAT - 12 on July 15, 2011 (Successful)
	PSLV-C16 launched RESOURCESAT - 2, YOUTHSAT and X-SAT on April 20, 2011 (Successful)
	PSLV-C15 launched CARTOSAT-2B, ALSAT-2A, NLS 6.1 & 6.2 and STUDSAT on July 12, 2010 (Successful)
	PSLV-C14 launched Oceansat - 2 and Six Nanosatellites on September 23, 2009 (Successful)
	PSLV-C12 launched RISAT-2 and ANUSAT on April 20, 2009 (Successfully)
	PSLV-C11 launched CHANDRAYAAN-I, on October 22, 2008 (Successful)
	PSLV-C9 launched CARTOSAT-2A, IMS-1 and Eight nano-satellites on April 28, 2008 (Successful)
	PSLV-C10 launched TECSAR on January 23, 2008 (Successful)
	PSLV-C8 launched AGILE on April 23, 2007 (Successful)
	PSLV-C7 launched CARTOSAT-2, SRE-1, LAPAN-TUBSAT and PEHUENSAT-1 on January 10, 2007 (Successful)
	PSLV-C6 launched CARTOSAT-1 and HAMSAT on May 5, 2005 (Successful)
	PSLV-C5 launched RESOURCESAT-1(IRS-P6) on October 17, 2003 (Successful)
	PSLV-C4 launched KALPANA-1(METSAT) on September 12, 2002 (Successful)
	PSLV-C3 launched TES on October 22, 2001 (Successful)
	PSLV-C2 launched OCEANSAT(IRS-P4), KITSAT-3 and DLR-TUBSAT on May 26, 1999 (Successful)
	PSLV-C1 launched IRS-1D on September 29, 1997 (Successful)
	PSLV-D3 launched IRS-P3 on March 21, 1996 (Successful)
	PSLV-D2 launched IRS-P2 on October 15, 1994 (Successful)
	PSLV-D1 launched IRS-1E on September 20, 1993 (Unsuccessful)

ISRO Launch Vehicles

Launch Vehicles are used to transport and put satellites or spacecrafts into space. In India, the launch vehicles development programme began in the early 1970s. The first experimental Satellite Launch Vehicle (SLV-3) was developed in 1980. An Augmented version of this, ASLV, was launched successfully in 1992. India has made tremendous strides in launch vehicle technology to achieve self-reliance in satellite launch vehicle programme with the operationalisation of Polar Satellite Launch Vehicle (PSLV) and Geosynchronous Satellite Launch Vehicle (GSLV).  

ISRO - Experimental / Small Satellites

Indian Experimental / Small Satellites ISRO has launched many small satellites mainly for the experimental purposes. This experiment include Remote Sensing, Atmospheric Studies, Payload Development, Orbit Controls, recovery technology etc. Launch Date 12.10.2011  The Jugnu nanosatellite, designed by Indian Institute of Technology, Kanpur under the guidance of ISRO  More.. Launch Date 12.10.2011  The SRMSat developed by the students and faculty of SRM University attempts to address the problem of Global warming and pollution levels in the atmosphere  More..

ISRO - Earth Observation Satellites

Indian Remote Sensing (IRS) satellite system was commissioned with the launch of IRS-1A, in 1988. With eleven satellites in operation, IRS is the largest civilian remote sensing satellite constellation in the world providing imageries in a variety of spatial resolutions, spectral bands and swaths. The data is used for several applications covering agriculture, water resources, urban development, mineral prospecting, environment, forestry, drought and flood forecasting, ocean resources and disaster management.
	Launch Date	26.04.2012
Radar Imaging Satellite-1 (RISAT-1) is a state of the art Microwave Remote Sensing Satellite carrying a Synthetic Aperture Radar (SAR) payload More..
	Launch Date	12.10.2011
Megha-Tropiques, a Joint Indo-French Satellite Mission for studying the water cycle and energy exchanges in the tropics More..