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Waning gibbous moon
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图注： This image, taken from the Southern Hemisphere (New Zealand), shows the waning gibbous Moon. During this lunar phase, we see most of the Moon's illuminated half with the unilluminated half only appearing as a dark crescent on the left. This phase comes after full moon and before last quarter moon (sometimes called half moon) .
来源： Dave Young / dcysurfer
来源链接
词汇表:
月相 , 亏凸月 , 凸月
分类：
太阳系
授权许可： 知识共享许可协议 Attribution 2.0 Generic 知识共享许可协议 Attribution 2.0 Generic 图标
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OAE Node France & OAE Center India Staff
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图注： Emmanuel Rollinde from the OAE Node France at CY Cergy Paris Univerity is welcomed by the OAE Center India staff.
来源： OAENF-CY and OAE Center India
The Speed of Spacecraft
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图注： This infographic is part of the "Simplifying Astronomy for Arabic Speakers" project, aiming to present scientific concepts in a simple and accessible way. The design focuses on the speed of spacecraft during the various stages of their launch, illustrating how velocity changes as the spacecraft progresses to reach the desired orbit.
Details of the Stages:
Stage One (Launch):
The spacecraft begins its journey by launching from the launch pad with an increasing speed. The velocity in this stage is influenced by Earth's gravity and atmospheric resistance.
After One Minute:
The spacecraft reaches a speed of approximately 1,600 kilometers per hour (km/h), reflecting a rapid acceleration powered by its engines.
After Two and a Half Minutes:
The rocket boosters are jettisoned, allowing the spacecraft to reach a speed of about 4,800 km/h. At this point, the spacecraft becomes lighter, enabling it to accelerate more efficiently.
Final Stage:
By the end of the ascent phase, the spacecraft achieves its final speed of approximately 28,000 km/h, allowing it to enter the desired orbit around Earth.
Through educational designs like this, the project provides enthusiasts with an opportunity to understand the intricate details of space missions in an engaging and simplified manner.
来源： Ali Al-Edhari ; Background image credit - NASA
词汇表:
火箭
语言： Arabic
文字系统： Arabic
授权许可： 知识共享许可协议 署名 4.0 国际 (CC BY 4.0) 知识共享许可协议 署名 4.0 国际 (CC BY 4.0) 图标
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Moon and Earth's thin atmosphere
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图注： Taken from the International Space Station (ISS), approximately 400 kilometers above the ground, the picture shows the Moon far in the background and Earth's thin atmosphere. It appears blue as light in this wavelength is scattered more than in others by the gases in the upper layers. The photo was taken in March 2015 by a crew member. Clearly visible is the vanishingly small layer of gases compared to Earth's dimensions. There is no clear border between the atmosphere and space; it is a smooth transition with no sharp edges. The thickness to the upper limit of the stratosphere, roughly 50 kilometers, does not even amount to one percent of Earth's radius. Above 600 kilometers, particles reaching the critical escape velocity can leave into space. The total mass of the atmosphere is around 300 times less than that of all oceans combined or one million times less than Earth's total mass.
来源： Earth Science and Remote Sensing Unit, NASA Johnson Space Center
来源链接
词汇表:
大气层
分类：
地球
授权许可： 公共领域 公共领域 图标
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3.99 MB)
Close-up view of a sunspot
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图注： This image of a sunspot was taken by the Daniel K Inouye Solar Telescope (DKIST), operated by the U.S. National Science Foundation. It was taken only in light with a wavelength of 530 nanometers, within the greenish-yellow part of the visible spectrum.
The picture reveals the detail of the spot's structure and the Sun’s photosphere. The dark central region, known as the umbra, is surrounded by a lighter area called the penumbra with radially elongated features stretching towards the umbra. Note that the umbra and penumbra here are not the same as the umbra and penumbra that occur during an eclipse.
The sunspot measures approximately 5000 kilometres in diameter, roughly equivalent to the east-west span of China. While the umbra appears black, it is actually hot and bright. It only appears dark because it is a few thousand kelvin cooler than the surrounding solar photosphere. Surrounding the sunspot, granulation patterns of plasma are visible on the photospheric surface of the Sun.
来源： NSO/NSF/AURA
来源链接
词汇表:
光球 , 太阳 , 太阳黑子 , 米粒组织
授权许可： 知识共享许可协议 署名 4.0 国际 (CC BY 4.0) 知识共享许可协议 署名 4.0 国际 (CC BY 4.0) 图标
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5.23 MB)
