CAPE CANAVERAL, Fla. — SpaceX was hoping to launch two rockets Sunday, but only the Falcon 9 rocket carrying a SAOCOM1B weather satellite went up on schedule.

What You Need To Know

The rocket took off at 7:18 p.m. ET without delay, despite rainy weather along Florida's Space Coast much of the day.

Sunday's first scheduled launch of the day, SpaceX's latest Starlink mission, was scheduled for 10:12 a.m. ET But the commercial space company stood down from the Starlink mission just before 8 a.m., during pre-flight operations, because of poor weather conditions.

Minutes after Sunday night's launch, the first stage booster landed back at Landing Zone 1, setting off a sonic boom.

A few minutes later, deployment of the SAOCOM1B satellite was confirmed.

Sunday's launch marked the first polar flight from Florida in more than 50 years. The rocket flew south off the Florida coast in order to position its payload to an orbit over Earth's poles.

Over the decades, the vast majority of polar launches took place from Vandenberg Air Force Base in California. The last polar launch at Cape Canaveral was a weather satellite in 1969.

On board the Falcon 9 Sunday was the SAOCOM 1-B, a weather satellite from Argentina's space agency. It's equipped with advanced radar imaging that can observe weather through cloud cover any time of day or night.

The Starlink satellite mission was rescheduled for 9:29 a.m. ET Tuesday.

If the double launch would have happened, it would have marked the shortest back-to-back launches from the Cape since 1966. 

Saturday's launch aborted at last second

Early Saturday morning, United Launch Alliance's launch of a Delta IV rocket was aborted.

Three seconds before liftoff, crews aborted the firing of its engines. The launch team only attributed the abort to an "unexpected condition."

It means a delay in sending up a classified spy satellite for the National Reconnaissance Office.​