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Although it looks more like an entity seen through a microscope than a telescope, this rounded object, named NGC 2022, is certainly not algae or tiny, blobby jellyfish. Instead, it is a vast orb of gas in space, cast off by an aging star. The star is visible in the orb’s center, shining through the gases it formerly held onto for most of its stellar life. When stars like the Sun grow advanced in age, they expand and glow red. These so-called red giants then begin to lose their outer layers of material into space. More than half of such a star’s mass can be shed in this manner, forming a shell of surrounding gas. At the same time, the star’s core shrinks and grows…

Standing among dead black spruce trees in a burned area near Delta Junction, Richard Chen, a graduate student at University of Southern California, dug soil sampling pits throughout the burned area to sample for organic carbon content of the soil, measure the depth-to-permafrost, and to make electronic measurements of soil moisture for NASA’s Arctic-Boreal Vulnerability Experiment (ABoVE) campaign. Wildfires in the Arctic often burn far away from populated areas, but their impacts are felt around the globe. From field and laboratory work to airborne campaigns and satellites, NASA is studying why boreal forests and tundra fires have become more frequent and powerful and what that means for climate forecasting, ecosystems and human health. Credits: NASA/Peter Griffith 在阿拉斯加三角洲交界处附近被烧毁的地区，矗立着死去的黑色云杉。右边的是南加州大学的研究生理查德•陈（Richard Chen），他正在整个燃烧区域内挖掘土壤取样坑，以采集土壤的有机碳含量样本，测量冻土层的深度，并为NASA的 ABoVE 项目进行土壤湿度的电子测量。 北极地区的野火燃烧通常发生在远离人烟的地方，但在世界各地都能感受到其影响。通过实地调研、实验室研究以及机载项目和卫星观测，美国国家航空航天局（NASA）正在研究为什么北方森林和冻原火灾变得更加频繁和剧烈，以及这对气候预测、生态系统和人类健康而言意味着什么。 影像来源：NASA/Peter Griffith

The pair of strange, luminescent creatures at play in this image are actually galaxies — realms of millions upon millions of stars. This galactic duo is known as UGC 2369. The galaxies are interacting, meaning that their mutual gravitational attraction is pulling them closer and closer together and distorting their shapes in the process. A tenuous bridge of gas, dust and stars can be seen connecting the two galaxies, created when they pulled material out into space across the diminishing divide between them. Interaction with others is a common event in the history of most galaxies. For larger galaxies like the Milky Way, the majority of these interactions involve significantly smaller so-called dwarf galaxies. But every few billion years, a more momentous event can occur….

This new Hubble Space Telescope view of Jupiter, taken on June 27, 2019, reveals the giant planet’s trademark Great Red Spot, and a more intense color palette in the clouds swirling in Jupiter’s turbulent atmosphere than seen in previous years. The colors, and their changes, provide important clues to ongoing processes in Jupiter’s atmosphere. The bands are created by differences in the thickness and height of the ammonia ice clouds. The colorful bands, which flow in opposite directions at various latitudes, result from different atmospheric pressures. Lighter bands rise higher and have thicker clouds than the darker bands. The new image was taken in visible light as part of the Outer Planets Atmospheres Legacy program, or OPAL. The program provides yearly Hubble global views of…

NASA astronaut candidate Raja Chari climbs into a NASA T-38 aircraft, Friday, July 12, 2019, at Ellington Field in Houston, Texas. Chari was selected by NASA to join the 2017 Astronaut Candidate Class and reported for duty in August 2017. The Iowa native graduated from the U.S. Air Force Academy in 1999 with bachelor’s degrees in astronautical engineering and engineering science. He earned a master’s degree in aeronautics and astronautics from Massachusetts Institute of Technology and is also a graduate from the U.S. Naval Test Pilot School. He’s among the NASA astronauts and astronaut candidates who will explore farther into the solar system than we’ve ever gone before. Watch: We Go as the Artemis Generation. Image Credit: NASA/Bill Ingalls 2019年7月12日星期五，美国航空航天局宇航员候选人拉贾·查里登上美国航空航天局的一架T-38飞机。Chari被美国宇航局选中加入2017年宇航员候选人班，并于2017年8月报到。这位爱荷华州人1999年毕业于美国空军学院，获得航天工程和工程科学学士学位。他在麻省理工学院获得航空航天硕士学位，同时也是美国海军试飞员学校的毕业生。 他是美国国家航空航天局的宇航员和宇航员候选人之一，他们将探索太阳系比我们以往任何时候都要深入。 观看视频:我们去探索，作为第一代阿尔特弥斯。 图片来源:NASA/Bill Ingalls

This week in 1971, Apollo 15 became the first mission to use the Lunar Roving Vehicle. The LRV was a lightweight, electric vehicle designed to operate in the low-gravity vacuum of the Moon. It was capable of traversing the lunar surface, allowing Apollo astronauts to extend the range of their extravehicular activities. Here, the LRV is photographed alone against the desolate lunar background following the third Apollo 15 EVA. This July, in a series of special events, NASA is marking the 50th anniversary of the Apollo Program — the historic effort that sent the first U.S. astronauts into orbit around the Moon in 1968, and landed a dozen astronauts on the lunar surface between 1969 and 1972. For more pictures, and to connect to NASA’s…