A chemical signature in Venus' clouds might be a sign of life, the sun started a new cycle, and human-created climate change continues to make its presence known across scientific data. These are some of the top stories this week from Space.com.

The sun is now in solar cycle 25.

A split image shows the sun during a solar cycle's maximum on the left (April 2014) and during a solar cycle's minimum on the right (December 2019). (Image credit: NASA/SDO)

Scientists have confirmed that the sun has begun the next chapter in its solar weather cycle. The new 11-year cycle of activity, called solar cycle 25, will likely fall into the same pattern of behavior as solar cycle 24, which ended in December 2019. Right now the sun is at a low-point in its activity, and the star is expected to slowly rev up activity until it reaches a peak in the summer of 2025.

Full story: The sun has begun a new solar weather cycle. It should be pretty quiet, scientists say.

A potential biosignature was found in Venus' clouds.

A new image of Venus shows the view ALMA had during its observations for the new research. (Image credit: ALMA (ESO/NAOJ/NRAO), Greaves et al.)

Venus took center stage this week's news after a team of astronomers announced they had found a chemical fingerprint on the planet that may signal the presence of life. Researchers found evidence of phosphine in Venus' clouds, which float high above the planet's scorching surface. Phosphine is only known to be produced by life forms, but more research is necessary to confirm that this detection points to a biosignature and not to an explanation that isn't linked to any life form's existence.

Full story: Strange chemical in clouds of Venus defies explanation. Could it be a sign of life?

See also: Life on Venus? Breakthrough Initiatives funds study of possible biosignature detection

A sobering peak ends an extensive, new climate data graph.

A climate map showing the last 66 million years of Earth's history (Image credit: Westerhold et al., CENOGRID)

On Sept. 10, scientists published the most detailed climate record of Earth ever created. The zig-zagging chart begins with the end of the dinosaurs and contains data about the 66 million years that spanned from that point in time to the present day. The peak at the end of the graph is a frightening reminder that the current pace of human-caused global warming far exceeds the natural climatic ups and down of any other point in the last 66 million years.

Full story: Earth barreling toward 'Hothouse' state not seen in 50 million years, epic new climate record shows

Initial tests show Arecibo Observatory didn't suffer damage to electronics.

Arecibo Observatory’s main collecting dish, which is among the world’s largest single-dish radio telescopes, was badly damaged when a cable snapped on Monday, Aug. 10. (Image credit: University of Central Florida)

A recovery effort is underway at the Arecibo Observatory in Puerto Rico after the telescope suffered extensive physical damage to its massive dish in August. Fortunately, initial tests of the telescope's receivers show no signs of electrical damage. Arecibo is well-known for tracking asteroids and advancing the search for extraterrestrial intelligence.

Full story: Alien-hunting telescope suffered 'no damage to electronics' during mysterious midnight disaster

Astra fails first orbital test launch.

Astra's Rocket 3.1 rises into the sky above Alaska's Pacific Spaceport Complex during the company's first orbital launch attempt on Sept. 11, 2020. The flight ended during the first-stage engine burn. (Image credit: Astra/John Kraus)

The spaceflight startup Astra launched its first orbital test flight from the Pacific Spaceport Complex on Alaska's Kodiak Island last week (Sept. 11), but the mission failed. The flight of Rocket 3.1 ended during the first stage burn when the vehicle drifted from its planned trajectory. According to an Astra blog post, this drift led to a commanded shutdown of the engines by the flight safety system.

Full story: Astra's 1st orbital test launch fails during first-stage engine burn

See also: Astra may make 2nd orbital launch attempt this year after test flight failure

Smoke from wildfires spreads across the continent and into Europe.

NOAA/NASA's Suomi NPP satellite's OMPS (Ozone Mapping Profiler Suite) aerosols from the U.S. wildfires are detected from space. (Image credit: NOAA/NASA/Worldview)

Emerging research and satellite observations show that the carbon monoxide and smog released by the wildfires raging along the U.S. West Coast is spreading across the country, northward into Canada and into Europe. This year's fires in California and Oregon have already emitted more carbon than any other year since 2003, according to data from the European Space Agency's Copernicus Atmosphere Monitoring Service (CAMS).

Full story: Smoke from US wildfires spreads across country and into Europe

A new Starship prototype may soon begin testing.

SpaceX's SN6 Starship prototype flies on a 500-foot-high test hop on Sept. 3, 2020. (Image credit: SpaceX)

SpaceX has recently performed test hops of a Mars-bound rocket. Two full-sized Starship spacecraft prototypes, SN5 and SN6, have performed 500-foot-high (150 meters) test hops at the company's South Texas facilities. Last week (Sept. 12), SpaceX founder and CEO Elon Musk tweeted that a new Starship prototype would soon be ready to begin testing, too.

Full story: SpaceX gearing up for 12-mile-high test flight with Starship SN8 prototype

See also: SpaceX delays next Starlink satellite fleet launch due to rocket 'recovery issue'

Giant exoplanet found orbiting near a stellar corpse.

Artist's illustration of WD 1856 b, a potential Jupiter-size planet, orbiting its much smaller host star, a dim white dwarf. (Image credit: NASA’s Goddard Space Flight Center)

Astronomers detected evidence of a giant planet that may have survived the death of its parent star. The Jupiter-sized planet orbits a stellar corpse located about 80 light-years from Earth. Scientists found this exoplanet using a NASA spacecraft called the Transiting Exoplanet Survey Satellite (TESS).

Full story: Big find! Scientists spot giant alien planet orbiting close to dead star's corpse

Two asteroids flew (safely) past Earth this week.

(Image credit: NASA JPL)

Two asteroids flew past Earth several hours apart on Monday (Sept. 14). Space rocks commonly fly past our planet, and these rocks did not pose any threat to Earth. The bus-sized asteroid called 2020 RF3 made the first approach, followed by a car-sized asteroid named 2020 RD4 more than half a day later.

Full story: 2 asteroids safely buzzed close by Earth this week

China performs an ocean-based launch from its new seaport facilities.

A Chinese Long March 11 rocket carrying nine Jilin-1 Gaofen-3 Earth observation satellites launches from the country's sea-based platform De Bo 3 in the Yellow Sea on Sept. 15, 2020. (Image credit: CASC)

China launched its second ocean-based launch mission on Tuesday (Sept. 15), sending nine satellites into orbit via its Long March 11 rocket. This week's launch is the first time China used its new seaport facilities at Haiyang in eastern China.

Full story: China launches 9 satellites into space from ocean platform

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