2019-07-19

封面上展示的是尼爾·阿姆斯特朗的影子投射在月球表面的情景。這張照片是1969年7月21日由阿姆斯特朗親自拍攝的，作為阿波羅11號(hào)著陸點(diǎn)全景圖的一部分，而當(dāng)時(shí)巴茲·奧爾德林正在部署科學(xué)儀器。太陽(yáng)就在阿姆斯特朗的正后方，在他的頭盔周?chē)纬闪艘粋€(gè)明亮的光環(huán)。從封面圖上可以看到，為了校正畸變，相機(jī)光學(xué)引入了黑十字。

Neil Armstrong's shadow cast on the surface of the Moon. This image was taken by Armstrong on 21 July 1969， as part of a panorama of the Apollo 11 landing site， while Buzz Aldrin deployed scientific instruments. The Sun was directly behind Armstrong， producing the appearance of a bright halo around his helmet. Black crosses were introduced by the camera optics for distortion calibration.

2019-07-26

海底冰川前緣融化的速度比預(yù)期的要快。封面圖上展示的是從阿拉斯加?xùn)|南部的勒孔特冰川崩解下來(lái)的冰山的一部分，它就是這一進(jìn)程引發(fā)的諸多后果之一，這個(gè)過(guò)程會(huì)造成質(zhì)量的損失，破壞冰蓋的穩(wěn)定，并導(dǎo)致海平面上升速度加快。

Submarine melting of ice at the leading edge of glaciers that discharge into the ocean is happening faster than expected. This section of an iceberg calved from LeConte Glacier in southeast Alaska illustrates one of the consequences of this process， which helps drive mass loss， destabilizes ice sheets， and leads to faster rates of sea level rise.

2019-08-02

封面圖展示的是在北京的一個(gè)實(shí)驗(yàn)室里，用基因編輯器CRISPR設(shè)計(jì)的抵抗一種細(xì)菌性疾病的番茄幼苗發(fā)芽了。中國(guó)在利用CRISPR改善農(nóng)作物方面走在了世界前列，并且中國(guó)的科學(xué)家也在制作幾種物種的疾病模型，以及用于人體移植的豬器官。但與此同時(shí)，對(duì)基因編輯器的另一種用途，也就是編輯人類(lèi)胚胎，卻引發(fā)了一場(chǎng)國(guó)際丑聞。

A tomato seedling engineered with the genome editor CRISPR to resist a bacterial disease sprouts in a Beijing laboratory. China is at the forefront of applying CRISPR to improve crops， and its scientists also are creating disease models in several species， as well as pig organs for transplantation into people. Another use， editing human embryos， triggered an international scandal.

2019-08-9

封面圖展示的是位于澳大利亞西部的射電望遠(yuǎn)鏡——澳大利亞平方千米陣列探路器（ASKAP）上方的銀河。ASKAP的36個(gè)碟形天線（封面圖上可以看到5個(gè)）共同運(yùn)作就像一個(gè)干涉儀一樣，可以精確定位射電源。天文學(xué)家利用ASKAP已經(jīng)確認(rèn)了一個(gè)快速射電暴的宿主星系，這種快速射電暴是一種持續(xù)僅1毫秒的閃光射電輻射。

The Milky Way seen above the Australian Square Kilometre Array Pathfinder （ASKAP）， a radio telescope located in Western Australia. ASKAP's 36 dishes （five visible here） work together as an interferometer to precisely locate radio sources. Astronomers using ASKAP have identified the host galaxy of a fast radio burst， a flash of radio emission lasting only a millisecond.

（陶陶 編譯）