Question: When did the largest economy in Africa launch its fourth satellite?

full_context: Document 1: Nigeria: Nigeria is often referred to as the ``Giant of Africa '', owing to its large population and economy. With 186 million inhabitants, Nigeria is the most populous country in Africa and the seventh most populous country in the world. Nigeria has the third - largest youth population in the world, after India and China, with more than 90 million of its population under age 18. The country is viewed as a multinational state as it is inhabited by over 500 ethnic groups, of which the three largest are the Hausa, Igbo and Yoruba; these ethnic groups speak over 500 different languages and are identified with a wide variety of cultures. The official language is English. Nigeria is divided roughly in half between Christians, who live mostly in the southern part of the country, and Muslims, who live mostly in the north. A minority of the population practise religions indigenous to Nigeria, such as those native to the Igbo and Yoruba ethnicities.
Document 2: Nigeria: As of 2015[update], Nigeria is the world's 20th largest economy, worth more than $500 billion and $1 trillion in terms of nominal GDP and purchasing power parity respectively. It overtook South Africa to become Africa's largest economy in 2014. Also, the debt-to-GDP ratio is only 11 percent, which is 8 percent below the 2012 ratio. Nigeria is considered to be an emerging market by the World Bank; It has been identified as a regional power on the African continent, a middle power in international affairs, and has also been identified as an emerging global power. Nigeria is a member of the MINT group of countries, which are widely seen as the globe's next "BRIC-like" economies. It is also listed among the "Next Eleven" economies set to become among the biggest in the world. Nigeria is a founding member of the Commonwealth of Nations, the African Union, OPEC, and the United Nations amongst other international organisations.
Document 3: BeiDou: The first satellite, BeiDou-1A, was launched on 30 October 2000, followed by BeiDou-1B on 20 December 2000. The third satellite, BeiDou-1C (a backup satellite), was put into orbit on 25 May 2003. The successful launch of BeiDou-1C also meant the establishment of the BeiDou-1 navigation system.
Document 4: Communications in Somalia: In November 2013, Somalia received its first fiber optic connection. The country previously had to rely on expensive satellite links due to the civil conflict, which limited internet usage. However, residents now have access to broadband internet cable for the first time after an agreement reached between Hormuud Telecom and Liquid Telecom. The deal will see Liquid Telecom link Hormuud to its 17,000 km (10,500 mile) network of terrestrial cables, which will deliver faster internet capacity. The fiber optic connection will also make online access more affordable to the average user. This in turn is expected to further increase the number of internet users. Dalkom Somalia reached a similar agreement with the West Indian Ocean Cable Company (WIOCC) Ltd, which it holds shares in. Effective the first quarter of 2014, the deal will establish fiber optic connectivity to and from Somalia via the EASSy cable. The new services are expected to reduce the cost of international bandwidth and to better optimize performance, thereby further broadening internet access. Dalkom Somalia is concurrently constructing a 1,000 square mile state-of-the-art data center in Mogadishu. The site will facilitate direct connection into the international fiber optic network by hosting equipment for all of the capital's ISPs and telecommunication companies.
Document 5: Nigeria: According to the International Organization for Migration, Nigeria witnessed a dramatic increase in remittances sent home from overseas Nigerians, going from USD 2.3 billion in 2004 to 17.9 billion in 2007. The United States accounts for the largest portion of official remittances, followed by the United Kingdom, Italy, Canada, Spain and France. On the African continent, Egypt, Equatorial Guinea, Chad, Libya and South Africa are important source countries of remittance flows to Nigeria, while China is the biggest remittance-sending country in Asia.
Document 6: Nigeria: Goodluck Jonathan served as Nigeria's president till 16 April 2011, when a new presidential election in Nigeria was conducted. Jonathan of the PDP was declared the winner on 19 April 2011, having won the election with a total of 22,495,187 of the 39,469,484 votes cast, to stand ahead of Muhammadu Buhari from the main opposition party, the Congress for Progressive Change (CPC), which won 12,214,853 of the total votes cast. The international media reported the elections as having run smoothly with relatively little violence or voter fraud, in contrast to previous elections.
Document 7: List of African countries by GDP (nominal): 2017 Rank Country Nominal GDP ($billions) Nominal GDP per capita (US $) Notes Nigeria 376.284 1,994.235 South Africa 349.299 6,179.870 Egypt 237.037 2,500.772 Algeria 178.287 4,292.272 Angola 124.209 4,407.657 6 Sudan 119.00 1,428.000 7 Morocco 109.824 3,151.145 8 Ethiopia 80.874 872.840 9 Kenya 79.511 1,701.550 10 Tanzania 51.725 1,033.567 11 Ghana 47.032 1,663.190 12 Democratic Republic of the Congo 41.441 478.237 13 Ivory Coast 40.360 1,616.981 14 Tunisia 40.275 3,496.286 15 Cameroon 34.006 1,400.743 16 Libya 31.331 4,858.672 17 Uganda 26.349 699.410 18 Zambia 25.504 1,479.542 19 Zimbabwe 17.491 1,175.723 20 Botswana 17.168 7,876.997 21 Senegal 16.463 1,038.094 22 Mali 15.318 810.771 23 Gabon 15.206 7,971.589 24 Namibia 12.687 5,413.508 25 Mozambique 12.681 429.296 26 Burkina Faso 12.569 663.806 27 Mauritius 12.428 9,794.102 28 Madagascar 11.463 447.558 29 Equatorial Guinea 10.725 12,726.956 30 Chad 9.872 810.163 31 Guinea 9.721 749.463 32 Benin 9.238 830.404 33 Rwanda 9.137 771.702 34 Congo 8.513 1,958.174 35 Niger 8.253 439.997 36 Somalia 7.382 547.32 37 Malawi 6.206 323.740 38 Eritrea 5.813 979.692 39 Mauritania 5.116 1,317.938 40 Togo 4.767 611.133 41 Swaziland 4.491 3,914.821 42 Sierra Leone 3.641 491.448 43 Burundi 3.396 312.463 44 Liberia 3.285 729.292 45 South Sudan 2.870 228.034 46 Lesotho 2.768 1,425.310 47 Djibouti 2.029 1,988.765 48 Central African Republic 1.928 386.806 49 Cape Verde 1.741 3,237.597 50 Seychelles 1.482 15,685.955 51 Guinea - Bissau 1.350 794.107 52 The Gambia 1.009 480.040 53 Comoros 0.652 787.831 54 São Tomé and Príncipe 0.379 1,785.280 -- Total 2,191.104
Document 8: BeiDou: In February 2007, the fourth and last satellite of the BeiDou-1 system, BeiDou-1D (sometimes called BeiDou-2A, serving as a backup satellite), was sent up into space. It was reported that the satellite had suffered from a control system malfunction but was then fully restored.
Document 9: Nigeria: Nigeria is often referred to as the "Giant of Africa", owing to its large population and economy. With approximately 182 million inhabitants, Nigeria is the most populous country in Africa and the seventh most populous country in the world. Nigeria has one of the largest populations of youth in the world. The country is viewed as a multinational state, as it is inhabited by over 500 ethnic groups, of which the three largest are the Hausa, Igbo and Yoruba; these ethnic groups speak over 500 different languages, and are identified with wide variety of cultures. The official language is English. Nigeria is divided roughly in half between Christians, who live mostly in the southern part of the country, and Muslims in the northern part. A minority of the population practise religions indigenous to Nigeria, such as those native to Igbo and Yoruba peoples.
Document 10: List of African countries by GDP (PPP): Region Rank Country 2015 GDP (PPP) millions of International dollars -- Africa 5,736,700 Nigeria 1,192.00 Egypt 995.97 South Africa 724.01 Algeria 570.64 Morocco 274.53 6 Angola 185.25 7 Sudan 167.42 8 Ethiopia 159.22 9 Tanzania 150.4 10 Kenya 143.05 11 Tunisia 127.21 12 Ghana 113.35 13 Libya 92.88 14 Uganda 79.75 15 Ivory Coast 78.34 16 Cameroon 72.11 17 Zambia 64.65 18 Democratic Republic of the Congo 63.27 19 Botswana 37.16 20 Senegal 36.30 21 Madagascar 35.56 22 Gabon 34.41 23 Chad 33.73 24 Mozambique 32.00 25 Burkina Faso 31.18 26 Mali 29.15 27 Zimbabwe 28.90 28 Republic of the Congo 27.92 29 Equatorial Guinea 25.94 30 Mauritius 24.84 31 Namibia 24.51 32 Benin 21.16 33 Malawi 20.56 34 Rwanda 20.32 35 Niger 18.96 36 Mauritania 16.43 37 Guinea 15.28 38 Swaziland 10.87 39 Togo 10.82 40 Eritrea 7.94 41 Burundi 7.88 42 Somalia 5.90 43 Lesotho 5.78 44 Gambia 3.27 45 Liberia 3.78 46 Cape Verde 3.48 47 Djibouti 3.09 48 Seychelles 2.53 49 Guinea - Bissau 1.94 50 Central African Republic 1.62 51 Comoros 1.21 52 São Tomé and Príncipe 0.66
Document 11: Nigeria: NigeriaSat-2, Nigeria's second satellite, was built as a high-resolution earth satellite by Surrey Space Technology Limited, a United Kingdom-based satellite technology company. It has 2.5-metre resolution panchromatic (very high resolution), 5-metre multispectral (high resolution, NIR red, green and red bands), and 32-metre multispectral (medium resolution, NIR red, green and red bands) antennas, with a ground receiving station in Abuja. The NigeriaSat-2 spacecraft alone was built at a cost of over £35 million. This satellite was launched into orbit from a military base in China.
Document 12: Nigeria: The Nigerian government has commissioned the overseas production and launch of four satellites. The Nigeriasat-1 was the first satellite to be built under the Nigerian government sponsorship. The satellite was launched from Russia on 27 September 2003. Nigeriasat-1 was part of the world-wide Disaster Monitoring Constellation System. The primary objectives of the Nigeriasat-1 were: to give early warning signals of environmental disaster; to help detect and control desertification in the northern part of Nigeria; to assist in demographic planning; to establish the relationship between malaria vectors and the environment that breeds malaria and to give early warning signals on future outbreaks of meningitis using remote sensing technology; to provide the technology needed to bring education to all parts of the country through distant learning; and to aid in conflict resolution and border disputes by mapping out state and International borders.
Document 13: Nigeria: Nigeria in recent years has been embracing industrialisation. It currently has an indigenous vehicle manufacturing company, Innoson Motors, which manufactures Rapid Transit Buses, Trucks and SUVs with an upcoming introduction of Cars. Nigeria also has few Electronic manufacturers like Zinox, the first Branded Nigerian Computer and Electronic gadgets (like tablet PCs) manufacturers. In 2013, Nigeria introduced a policy regarding import duty on vehicles to encourage local manufacturing companies in the country. In this regard, some foreign vehicle manufacturing companies like Nissan have made known their plans to have manufacturing plants in Nigeria. Ogun is considered to be the current Nigeria's industrial hub, as most factories are located in Ogun and more companies are moving there, followed by Lagos.
Document 14: Nigeria: Nigeria was ranked 30th in the world in terms of GDP (PPP) in 2012. Nigeria is the United States' largest trading partner in sub-Saharan Africa and supplies a fifth of its oil (11% of oil imports). It has the seventh-largest trade surplus with the US of any country worldwide. Nigeria is the 50th-largest export market for US goods and the 14th-largest exporter of goods to the US. The United States is the country's largest foreign investor. The International Monetary Fund (IMF) projected economic growth of 9% in 2008 and 8.3% in 2009. The IMF further projects an 8% growth in the Nigerian economy in 2011.
Document 15: Nigeria: On 24 March 2009, the Nigerian Federal Ministry of Science and Technology, NigComSat Ltd. and CGWIC signed another contract for the in-orbit delivery of the NigComSat-1R satellite. NigComSat-1R was also a DFH-4 satellite, and the replacement for the failed NigComSat-1 was successfully launched into orbit by China in Xichang on December 19, 2011. The satellite according to then-Nigerian President Goodluck Jonathan which was paid for by the insurance policy on NigComSat-1 which de-orbited in 2009, would have a positive impact on national development in various sectors such as communications, internet services, health, agriculture, environmental protection and national security.
ground_truth: December 19, 2011
sub_queries: What is the largest economy in Africa? Answer: Nigeria
When was Nigeria 's fourth satellite launched? Answer: December 19, 2011