NASA's Hubble Space Telescope captures photos of dark red storms raging in Jupiter's Northern hemisphere

• NASA's Hubble Space Telescope snapped new photos of Jupiter's turbulent surface.
• The photos depict dark red cyclones in the gas giant's Northern hemisphere.

The latest photos of Jupiter, taken by NASA's Hubble Space Telescope and released Thursday show new storms in the planet's northern hemisphere — but the gas giant still holds secrets, experts say.

Each year, Hubble dedicates a few days of its precious run time to snap pictures of our solar system's outer planets.

"Jupiter's colorful appearance is due to different chemicals in the planet's atmosphere reflecting sunlight," Affelia Wibisono, a researcher at the Mullard Space Science Laboratory at University College London, told Insider.

Powerful storms can pull phosphorus, sulfur, and hydrocarbons from deep in Jupiter's atmosphere up to its cloud tops, which appear as white and brown spots, Wibisono said, adding, "This new Hubble image of Jupiter has allowed scientists to keep track of Jupiter's storms and to understand the planet's weather patterns by monitoring the color changes in its atmosphere."

Check out the highlights from Jupiter's 2021 portrait session, below:

New, dark red storms appeared in Jupiter's Northern hemisphere

This year, several new storms, or "barges," appeared north of the planet's equator, according to NASA.

"Barges are cloudless regions in Jupiter's atmosphere," Wibisono said. They can be difficult to see since they're usually similar in color to their surroundings, but against Jupiter's lighter North Equatorial Belt, they stand out.

Scientists thought Jupiter's equatorial zone would change colors. It didn't.

Jupiter's equatorial band has stayed stubbornly orange, even though scientists expected this year's portrait to show it fading to its typical beige hue.

That band has turned orange-red in the past. In those instances, the color change came with bright infrared light as deep clouds cleared away. This time, that didn't happen, because new red layer was much shallower.

Mike Wong, a planetary scientist at University of California, Berkeley, thought the red layer would be weak and fading by now. "It now seems like a shallower event does not necessarily mean a shorter-duration event," he told Insider.

Despite its name, Jupiter's 'Red Spot Jr.' is still beige

Jupiter's Great Red Spot gained a companion in 2000, a gigantic storm called Red Spot Jr., when three smaller storms merged together. It's about as big as Earth and travels eastward, in the opposite direction that the Great Red Spot moves.

"Solar ultraviolet light can cause a chemical change to some of this material that causes red spots, such as the Great Red Spot and the Red Spot Jr," Wibisono said.

When it first formed, Red Spot Jr. was called Oval BA — that is, until it turned red in 2006, prompting scientists to liken it to the Great Red Spot. Since then, however, Red Spot Jr. has reverted to a shade closer to white.

A slight darkening of the Red Spot Jr., seen in 2020, prompted scientists to suggest it was turning red again, but Thursday's photos suggest that's not the case. Instead, Red Spot Jr. remains light in color.

Decades-old Hubble is struggling. A replacement telescope is set to launch next month.

It's been a tough year for Hubble, which launched in 1990.

Twice this year, the world's most powerful space telescope glitched, first in June and again in November, forcing its science instruments into hibernation.

Beleaguered Hubble also has competition. The James Webb Space Telescope features a 21.3-foot-wide, gold-plated mirror and a substantially larger field of view than its predecessor, which will allow it to peer farther into the universe. Webb is due to launch late next month.