Venus, often called Earth's "evil twin" planet, formed closer to the sun and has since evolved quite differently from our own planet. It has a "runaway" greenhouse effect (meaning heat is completely trapped), a thick carbon-dioxide-rich atmosphere, no magnetic field and a surface hot enough to melt lead.

Several uncrewed scientific missions will study how and why that happened in the next decade. But now some scientists want to send a crewed mission there as well for a flyby. Is that a good idea?

With a slightly smaller diameter than Earth, Venus orbits closer to the sun. This means that any water on the surface would have evaporated shortly after its formation, starting its greenhouse effect. Early and sustained volcanic eruptions created lava plains and increased the carbon dioxide in the atmosphere—starting the runaway greenhouse effect, which increased the temperature from just a little higher than Earth's to its current high value of 475°C.

While the Venus year is shorter than ours (225 days), its rotation is very slow (243 days) and "retrograde"—the other way round to Earth. The slow rotation is related to a lack of magnetic field, resulting in a continuing loss of atmosphere.

A year after its first rocket launch failed, a new aerospace company was unsuccessful early Friday in its second attempt to place multiple satellites into orbit.

Firefly Aerospace's Alpha rocket was unable to lift off from Vandenberg Space Force Base, California, and follow a planned arc over the Pacific Ocean toward space.

A live video feed showed the launch countdown go to zero and then abort at 12:52 a.m. Friday.

"The vehicle went into auto abort after ignition. This is designed into the system to ensure safety," the company said in a Twitter post. "The team scrubbed tonight's launch attempt and is reviewing data to determine our next launch window."

The rocket's payload included multiple small satellites designed for a variety of technology experiments and demonstrations as well as educational purposes.

The mission, dubbed "To The Black," was the company's second demonstration flight of its entry into the market for small satellite launchers.

The first Alpha was launched from Vandenberg on Sept. 2, 2021, but did not reach orbit.

One of the four first-stage engines shut down prematurely but the rocket continued upward on three engines into the supersonic realm where it tumbled out of control.

The rocket was then intentionally destroyed by an explosive flight termination system.