哈勃望远镜发现一个有卷须的星系

哈勃望远镜发现一个有卷须的星系

ByNASA中文

This image taken with the NASA/ESA Hubble Space Telescope shows JO204, a ‘jellyfish galaxy’ so named for the bright tendrils of gas that appear in this image as drifting lazily below JO204’s bright central bulk. The galaxy lies almost 600 million light-years away in the constellation Sextans. Hubble observed JO204 as part of a survey performed with the intention of better understanding star formation under extreme conditions. While the delicate ribbons of gas beneath JO204 may look like floating jellyfish tentacles, they are in fact the outcome of an intense astronomical process known as ram pressure stripping. Ram pressure is a particular type of pressure exerted on a body when it moves relative to a fluid. An intuitive example is the sensation of pressure you…

哈勃发现了一个多代星团

哈勃发现了一个多代星团

ByNASA中文

This image from the NASA/ESA Hubble Space Telescope shows the globular star cluster NGC 2419. Globular clusters are both beautiful and fascinating. They are spherical groups of stars that orbit the center of a galaxy, and in the case of NGC 2419, that galaxy is our own Milky Way. NGC 2419 is around 300,000 light-years from the solar system, in the constellation Lynx. The stars populating globular clusters are very similar because they formed at roughly the same time. Astronomers can determine a star’s relative age by its chemical makeup, a property called its metallicity. Because stars in a globular cluster all formed at around the same time, they tend to display similar properties. Astronomers believed this similarity included their stellar helium content. They thought…

NASA的詹姆斯·韦伯太空望远镜测量了一颗岩质系外行星的温度

NASA的詹姆斯·韦伯太空望远镜测量了一颗岩质系外行星的温度

ByNASA中文

一个国际研究团队使用NASA的詹姆斯·韦伯太空望远镜测量了岩质系外行星TRAPPIST-1 b的温度。测量基于该行星的热辐射：韦伯的中红外仪器（MIRI）检测到的以红外光形式释放的热能。结果表明，这颗行星的昼面温度约为500开尔文（约450华氏度），并表明它没有明显的大气层。

NASA的詹姆斯·韦伯太空望远镜在遥远的星球上发现了旋转的沙砾状云

NASA的詹姆斯·韦伯太空望远镜在遥远的星球上发现了旋转的沙砾状云

ByNASA中文

研究人员用NASA的詹姆斯·韦伯太空望远镜观测，在一颗遥远行星的大气中确定了硅酸盐云的特征。在22小时的一天中，大气不断上升、混合和移动，使较热的物质上升，使较冷的物质下降。由此产生的亮度变化如此剧烈，以至于它是迄今为止已知的变化了最大的行星质量天体。由亚利桑那大学的布列塔尼·迈尔斯领导的研究团队还利用韦伯的数据非常清楚地探测到了水、甲烷和一氧化碳，并发现了二氧化碳存在的证据。这是迄今为止在太阳系以外的行星上同时发现的分子数量最多的一次。