Sputnik

**Sputnik** refers to the world's first artificial satellite, **Sputnik 1**, launched by the Soviet Union on **October 4, 1957**. Here's a detailed overview:

### Key Facts:

- **Name Meaning**: "Sputnik" translates to "satellite" or "fellow traveler" in Russian.  

- **Design**: A polished metal sphere (58 cm/23 inches in diameter) with four external antennas, weighing **83.6 kg**.  

- **Launch Vehicle**: Carried into orbit by an **R-7 Semyorka** rocket from Kazakhstan.  

### Mission Details:

- **Orbit**: Circled Earth every **98 minutes** at an altitude of about 250 km (155 miles).  

- **Signals**: Transmitted radio pulses at **20.005 and 40.002 MHz**, detectable globally for **21 days** until its batteries died.  

- **Duration**: Remained in orbit for **3 months** before burning up on re-entry.  

### Historical Context:

- **Cold War**: Marked the start of the **Space Race** between the USSR and the US, intensifying Cold War rivalry.  

- **International Geophysical Year**: Part of a global scientific initiative to study Earth and space phenomena.  

### Impact:

- **Sputnik Crisis**: Prompted the US to establish **NASA** (1958) and boost investments in STEM education and technology.  

- **Military Implications**: Demonstrated Soviet rocket capability, raising concerns about intercontinental ballistic missiles (ICBMs).  

- **Legacy**: Catalyzed advancements in space exploration, leading to milestones like the **Apollo Moon landings**.  

### Follow-Up Missions:

- **Sputnik 2** (November 3, 1957): Carried **Laika**, the first living creature (a dog) in orbit.  

### Cultural Significance:

- Symbolized technological prowess and shifted global perceptions of scientific leadership.  

- Visible from Earth, its "beep" became an iconic sound of the Space Age.  

Sputnik 1 remains a landmark achievement, reshaping geopolitics, science, and humanity's journey into space.