This week in science

Artemis target launch dates and more: Understand the world through 8 images

NASA

EVA MARIE UZCATEGUI/AFP/Getty Images

Here are the biggest science stories of the week, told in 8 striking images

Andre Rerekura, Australian Institute of Marine Science

8. Land is overrated

Tom Stewart

July 20

Scientists found a relative of the Tiktaalik (one of the earliest animals to move onto dry land) may have returned to the sea after its ancestors left. Analysis of its fins show it was more suited to swimming than walking, complicating the picture of tetrapod evolution.

Alex Boersma

7. Warming up

Luiza Soares

July 20

Scientists discovered mammal ancestors developed warm blood quicker and more recently than thought. Studying fossils from around the skull’s ear canals (which are smaller in warm-blooded animals), they determined warm blood evolved at roughly the same time as whiskers and fur, 233 million years ago.

Luzia Soares

6. A look back in time

NASA/ JPL-Caltech

July 21

Astronomers developed a process to observe early stars through the thick hydrogen clouds surrounding them. The machine learning approach could filter out signal sources that interfere with observations, letting them see some of the first stars formed after the Big Bang.

NASA/ JPL-Caltech

5. Ready for launch?

Northrop Grumman

July 22

NASA set new target dates for its Artemis I launch: August 29, September 2, and September 5. The announcement came after NASA completed a full-state booster test and addressed a fuel leak that occurred during the last SLS wet dress rehearsal.

Northrop Grumman

4. Eye in the sky

NASA/Landsat 9 OLI-2

July 23

This week marked the 50th anniversary of Landsat, NASA’s longest-running satellite observation of Earth. Among other uses, Landsat images have contributed to tracking and managing wildfire, like the Oak fire currently burning in California.

NASA/Landsat 9 OLI-2

3. Ultimate omnivore

Andre Rerekura, Australian Institute of Marine Science

July 24

Researchers determined whale sharks use a type of seaweed as a major food source. That would make the more than 30-foot-long sharks the world’s largest omnivore.

Andre Rerekura, Australian Institute of Marine Science

2. Hotter and hotter

SCSIO

July 25

Scientists determined extreme heatwaves will increase by 30 percentage points in the near future, two-thirds of which is due to human activity. Greenhouse gases can disrupt atmospheric circulation, leading to increased heatwaves.

SCSIO

1. Where there’s smoke...

Jim Caldwell, Bureau of Land Management.

July 27

Researchers found smoke plumes from wildfires are getting taller, increasing by 750 feet per year in some places, due to the same climate change conditions that drive fires themselves. Taller plumes could disperse more aerosols, degrading air quality more and over a larger area.

Jim Caldwell, Bureau of Land Management