We may not be alone. There are far more planets in our solar system than previously thought and some of them might have life on them.

European astronomers have found 32 new planets outside our solar system, adding evidence to the theory that the universe has many places where life could develop. Scientists using the European Southern Observatory telescope didn’t find any planets quite the size of Earth or any that seemed habitable or even unusual. But their announcement increased the number of planets discovered outside the solar system to more than 400.

Six of the newly found planets are several times bigger than Earth, increasing the population of so-called super-Earths by more than 30 percent. Most planets discovered so far are far bigger, Jupiter-sized or even larger.

Two of the newly discovered planets were as small as five times the size of Earth and one was up to five times larger than Jupiter.

Astronomer Stephane Udry of the University of Geneva said the results support the theory that planet formation is common, especially around the most common types of stars.

“I’m pretty confident that there are Earth-like planets everywhere,” Udry said in a Web-based news briefing from a conference in Portugal. “Nature doesn’t like a vacuum. If there is space to put a planet there, there will be a planet there.”

What astronomers said is especially exciting is that about 40 percent of sun-like stars have planets that are closer to being Earth-sized than the size of Jupiter. Jupiter’s mass is more than 300 times that of Earth’s.

Depending on definitions of the size of super-Earths, the discovery suggests that planets that have a mass similar to Earth’s are “extraordinarily commonplace,” said Alan Boss, an astronomer at the Carnegie Institution of Washington. He was not part of the European team. “The universe must indeed be crowded with habitable worlds.”

Boss said finding 32 planets at once is a record “and it really shows that the Europeans have taken the lead” in finding planets outside the solar system.

The discoveries were made by the High Accuracy Radial Velocity Planet Searcher, which is an attachment to the European observatory telescope in Chile that looks for slight wobbles in a star’s movements. Those changes would be made by the tug of a planet’s gravity on the star. There are no photos of these planets.

And more news of life in space.

The basic molecules required for life as we know it have been detected in a second hot gas planet beyond our solar system.

The planet, which orbits a sun-like star about 150 light-years away in the constellation Pegasus, is not habitable but it has the same chemistry that, if found around a rocky planet in the future, could indicate a world that might support life or the presence of life.

“It’s the second planet outside our solar system in which water, methane and carbon dioxide have been found, which are potentially important for biological processes in habitable planets,” said researcher Mark Swain of NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “Detecting organic compounds in two exoplanets now raises the possibility that it will become commonplace to find planets with molecules that may be tied to life.”

The first planet in which organic molecules were detected was HD 189733b, a hot, Jupiter-sized planet. The discovery was made by Swain and his colleagues in December 2008.

Swain’s team used data from two of NASA’s orbiting Great Observatories, the Hubble Space Telescope and Spitzer Space Telescope, to study another hot planet bigger than Jupiter, HD 209458b, and characterize it as the second known exoplanet with organic signatures.

The detections were made through spectroscopy, which splits light into its components to reveal the distinctive spectral signatures of different chemicals. Data from Hubble’s near-infrared camera and multi-object spectrometer revealed the presence of the molecules, and data from Spitzer’s photometer and infrared spectrometer measured their amounts.

“This demonstrates that we can detect the molecules that matter for life processes,” Swain said.

Astronomers can now begin comparing the two planetary atmospheres for differences and similarities. For example, the relative amounts of water and carbon dioxide in the two planets is similar, but HD 209458b shows a greater abundance of methane than HD 189733b.

“The high methane abundance is telling us something,” Swain said. “It could mean there was something special about the formation of this planet.”

Other large, hot Jupiter-type planets can be characterized and compared in the same way. The techniques used are also similar for those that will be required to shortlist rocky Earth-like planets where the signatures of organic chemicals might indicate the presence of life.

Rocky worlds are expected to be found by NASA’s Kepler mission, which launched earlier this year, but astronomers believe we are a decade or so away from being able to detect any chemical signs of life on such a body.

If and when such Earth-like planets are found in the future, “the detection of organic compounds will not necessarily mean there’s life on a planet, because there are other ways to generate such molecules,” Swain said. “If we detect organic chemicals on a rocky, Earth-like planet, we will want to understand enough about the planet to rule out non-life processes that could have led to those chemicals being there.”