
Home > Terms > Serbo Croatian (SH) > Prenektarski period
Prenektarski period
The geologic history of Earth's Moon has been divided into five broad time periods, or systems. From oldest to youngest, these are pre-Nectarian, Nectarian, Imbrian, Eratosthenian, and Copernican. These systems are defined by the number of impact craters on the ground surface (more craters = older surface) correlated to the absolute ages determined for the lunar rock samples returned to Earth by the U. S. Apollo missions and unpiloted Soviet Luna missions. The pre-Nectarian system extends from 4. 5 billion to 3. 9 billion years ago.
0
0
Cải thiện
- Loại từ: noun
- Từ đồng nghĩa:
- Blossary:
- Ngành nghề/Lĩnh vực: Astronomy
- Category: Planetary science
- Company: PSRD
- Sản phẩm:
- Viết tắt-Từ viết tắt:
Ngôn ngữ khác:
Bạn muốn nói gì?
Terms in the News
Featured Terms
Ngành nghề/Lĩnh vực: Arts & crafts Category: Oil painting
Mona Liza
The Mona Lisa is widely recognized as one of the most famous paintings in the history of art. It is a half-length portrait of a seated woman painted ...
Người đóng góp
Featured blossaries
dnatalia
0
Terms
60
Bảng chú giải
2
Followers
Twilight Saga Characters
Chuyên mục: Literature 1
11 Terms


Browers Terms By Category
- Software engineering(1411)
- Productivity software(925)
- Unicode standard(481)
- Workstations(445)
- Computer hardware(191)
- Desktop PC(183)
Computer(4168) Terms
- Skin care(179)
- Cosmetic surgery(114)
- Hair style(61)
- Breast implant(58)
- Cosmetic products(5)
Beauty(417) Terms
- Inorganic pigments(45)
- Inorganic salts(2)
- Phosphates(1)
- Oxides(1)
- Inorganic acids(1)
Inorganic chemicals(50) Terms
- Fuel cell(402)
- Capacitors(290)
- Motors(278)
- Generators(192)
- Circuit breakers(147)
- Power supplies(77)
Electrical equipment(1403) Terms
- Physical geography(2496)
- Geography(671)
- Cities & towns(554)
- Countries & Territories(515)
- Capitals(283)
- Human geography(103)