Scientists still have a long way to go before they can say definitively what’s creating the phosphine — a possible signature of life — detected on Venus.

The big picture: Science is an iterative process, and this discovery is no exception.

The discovery of possible sign of life on Venus is buoying a push by many in the planetary science community to get NASA and other space agencies to send missions to Venus that could sniff out if there really is life there.

Why it matters: NASA hasn't sent a dedicated spacecraft to study Venus from close range in about 30 years, with much of the hunt for life in the solar system focusing instead on Mars.

Scientists think they may have found an indicator of life in Venus’ clouds — a discovery that, if confirmed, will cause them to re-examine everything they thought they knew about how life evolves.

The big picture: If life does exist within a small niche of habitability in Venus' temperate layer of clouds, it might mean that life could be even more ubiquitous in the universe than previously expected. The discovery is already fueling calls from scientists who want a mission sent to the nearby world.

Traces of a gas in Venus' clouds could indicate some form of life may exist there, according to a study published today.

Why it matters: Scientists have been musing about the possibility that life exists in Venus' temperate clouds for decades. If confirmed as a sign of life, the finding would open up a new era of science.

NASA is asking private companies to help the space agency collect dirt and rocks from the Moon, NASA administrator Jim Bridenstine announced today.

Why it matters: The solicitation is part of NASA's push to commercialize space and make the agency a buyer of services in space instead of a sole provider.

A new space policy directive issued by the Trump administration last week calls on the space industry to develop cybersecurity measures to protect essential satellites in orbit.

Why it matters: GPS, communications and other satellites are integral to U.S. national security. As other nations continue to develop their space capabilities, experts are warning that key U.S. assets in orbit could be vulnerable to attacks.

Researchers have found rust on the Moon, complicating our picture of how Earth's natural satellite has evolved over the course of billions of years.

Why it matters: Understanding the Moon and its composition is key not just for scientists working to learn more about how planetary systems form and change over time but for future explorers who hope to make use of lunar resources.

The hunt for dark matter — the mysterious substance that makes up the majority of matter in the universe but hasn't been directly observed — is turning to new places and looking for new candidates.

The big picture: Regular matter — the stuff that makes up you, me and everything we know and see out in the universe — is only 15% of the total matter in the universe.

Genetically enhanced mice retained or increased muscle mass after spending a month on the International Space Station.

Why it matters: The findings of the study, published Monday in the journal Proceedings of the National Academy of Sciences, suggest that muscle and bone loss could be mitigated for astronauts on space flights as well as for people on Earth who experience muscle degeneration.

Three stars are ripping apart a potentially planet-forming disc of gas and dust 1,300 light-years from Earth.

Why it matters: The star system could help scientists learn more about how some of the strangest systems of planets and stars form in the galaxy.