The Falcon 9 SpaceX rocket lifts off from Space Launch Complex 40 at the Cape Canaveral Air Force Station in Cape Canaveral, Fla., Saturday, Jan. 10, 2015. SpaceX is on a resupply mission to the International Space Station. (AP Photo/John Raoux)
John Raoux/AP
The Falcon 9 SpaceX rocket lifts off from Space Launch Complex 40 at the Cape Canaveral Air Force Station in Cape Canaveral, Fla., Saturday, Jan. 10, 2015. SpaceX is on a resupply mission to the International Space Station. (AP Photo/John Raoux)
Now playing
01:38
Liftoff: SpaceX's Dragon 9 heads for the ISS
NASA releases first ever ISS video shot at 8K
NASA
NASA releases first ever ISS video shot at 8K
Now playing
01:16
NASA shoots first 8K video of Earth
NASA
Now playing
00:59
Why did NASA launch 450,000 gallons of water?
In this photo released by NASA, the Northrop Grumman Antares rocket, with Cygnus resupply spacecraft onboard, launches from Pad-0A, Saturday, Nov. 17, 2018 at NASA's Wallops Flight Facility in Va. (Joel Kowsky/NASA via AP)
Joel Kowsky/NASA/AP
In this photo released by NASA, the Northrop Grumman Antares rocket, with Cygnus resupply spacecraft onboard, launches from Pad-0A, Saturday, Nov. 17, 2018 at NASA's Wallops Flight Facility in Va. (Joel Kowsky/NASA via AP)
Now playing
00:34
Watch NASA launch cargo ship into space
SANTA BARBARA, CA - OCTOBER 07: The SpaceX Falcon 9 rocket (R) separates from the space craft (L) behind the rocket trail after launching from Vandenberg Air Force Base carrying the SAOCOM 1A and ITASAT 1 satellites, as seen on October 7, 2018 near Santa Barbara, California. After launching the satellites, the Falcon 9 rocket successfully returned to land on solid ground near the launch site rather than at sea. The satellites will become part of a six-satellite constellation that will work in tandem with an Italian constellation known as COSMO-SkyMed.    (Photo by David McNew/Getty Images)
David McNew/Getty Images
SANTA BARBARA, CA - OCTOBER 07: The SpaceX Falcon 9 rocket (R) separates from the space craft (L) behind the rocket trail after launching from Vandenberg Air Force Base carrying the SAOCOM 1A and ITASAT 1 satellites, as seen on October 7, 2018 near Santa Barbara, California. After launching the satellites, the Falcon 9 rocket successfully returned to land on solid ground near the launch site rather than at sea. The satellites will become part of a six-satellite constellation that will work in tandem with an Italian constellation known as COSMO-SkyMed. (Photo by David McNew/Getty Images)
Now playing
01:09
SpaceX rocket launch lights up evening sky
JAXA astroid ryugu images
Twitter / @haya2e_jaxa
JAXA astroid ryugu images
Now playing
00:33
Robot sends new images from asteroid's surface
Massive structure on Saturn
NASA
Massive structure on Saturn
Now playing
01:05
New vortex discovered above Saturn
The SpaceX launch of a Falcon 9 rocket marks another milestone for Kennedy Space Center's Launch Complex 39-A.
NASA
The SpaceX launch of a Falcon 9 rocket marks another milestone for Kennedy Space Center's Launch Complex 39-A.
Now playing
02:00
60 years of NASA's history in 120 seconds
NASA TV
Now playing
01:39
Watch NASA launch probe that will explore sun
nasa lagoon nebula new images lon orig_00000000.jpg
NASA
nasa lagoon nebula new images lon orig_00000000.jpg
Now playing
01:19
Stunning virtual tour of the Lagoon Nebula
Artist's concept of the Solar Probe Plus spacecraft approaching the sun. In order to unlock the mysteries of the corona, but also to protect a society that is increasingly dependent on technology from the threats of space weather, we will send Solar Probe Plus to touch the sun.
Johns Hopkins University Applied Physics Laboratory/NASA
Artist's concept of the Solar Probe Plus spacecraft approaching the sun. In order to unlock the mysteries of the corona, but also to protect a society that is increasingly dependent on technology from the threats of space weather, we will send Solar Probe Plus to touch the sun.
Now playing
00:59
Listen: The sun is not silent
NASA's Goddard Space Flight Center/David Ladd
Now playing
01:26
Breathtaking virtual tour of the Moon in 4K
This composite image, derived from data collected by the Jovian Infrared Auroral Mapper (JIRAM) instrument aboard NASA's Juno mission to Jupiter, shows the central cyclone at the planet's north pole and the eight cyclones that encircle it.
NASA/JPL-Caltech/SwRI/ASI/INAF/JIRAM
This composite image, derived from data collected by the Jovian Infrared Auroral Mapper (JIRAM) instrument aboard NASA's Juno mission to Jupiter, shows the central cyclone at the planet's north pole and the eight cyclones that encircle it.
Now playing
01:02
NASA mission discovers Jupiter's inner secrets
N.R.Fuller, National Science Foundation
Now playing
00:46
'Fingerprint' of earliest light in universe detected
Now playing
00:46
'Super blue blood moon' lights up the skies
what is a black moon orig jpm_00000000.jpg
NASA
what is a black moon orig jpm_00000000.jpg
Now playing
01:04
What's in a moon's name?

Story highlights

NEW: Soft landing of booster fails, but launch and rest of flight successful

The "Dragon" capsule is heading with supplies to the International Space Station

CNN —  

In spite of a successful rocket launch on Saturday, things didn’t quite work out as SpaceX had hoped, when it tried to make history with an experiment.

The Falcon 9 rocket lifted off as scheduled at 4:47 a.m. ET from Cape Canaveral, Florida, on a routine mission to resupply the International Space Station.

What went up is doing fine. What came down didn’t quite, but the the rocket scientists were almost counting on that, and they’re not too disappointed.

The company tried to land the first section of the rocket, which is 14 stories tall, back down gingerly and on its feet on Earth, while the rest of the rocket continued on.

A floating landing pad was waiting out in the Atlantic ocean for the booster. It made it there, but came down a little too hard, SpaceX founder Elon Musk said in a tweet.

“Rocket made it to drone spaceport ship, but landed hard. Close, but no cigar this time.”

Don’t lose it; reuse it

Normally, once it has vaulted the rest of the rocket to space, the huge booster falls back into the ocean as, basically, garbage. That has been compared to throwing away a Boeing 747 passenger jet after it makes one transatlantic flight.

But SpaceX has been determined to change the practice to save millions in costs. Instead of losing the biggest part of the rocket, the company aims to reuse it.

The Falcon 9 is made up of two sections, called stages, that contain engines. On top of the rocket is the capsule, which carries its payload. It could also carry astronauts some day.

After the launch – then the separation from the second stage of the rocket – the Falcon 9 rocket’s booster turned around to head back down to the floating platform.

The company logo’s signature “X” marked the spot in the middle of a bull’s eye on the black tarmac of the “spaceport drone ship” that plowed through the water autonomously – with no need of human drivers, who could get hurt in a bang-up.

Some stuff on the ship did get dinged when the rocket plunked down on it, Musk said in a tweet.

Second try

The originally planned launch on Tuesday was scrubbed due to technical issues that turned up in the rocket’s second stage.

Scratching a launch time is routine for the space industry – sometimes due to weather, sometimes for technical reasons.

As Musk said when a different model rocket self-detonated as a safety measure during a soft-landing test in August: “Rockets are tricky.”

The official mission

Though the landing was a test, the launch was not. The “Dragon” capsule is carrying a payload of up to about 5,000 pounds to the ISS.

With five previous trips, the resupply missions have become somewhat routine. And this one appeared to be going as planned on Saturday.

The Dragon will land back on Earth the usual way in four and a half weeks, plopping into ocean water, after blazing back through the atmosphere with red-hot heat shields glowing at up to 3,000 degrees Fahrenheit.

The historic part

SpaceX has tried the landing experiment before, with the exception of the last step. If the Falcon 9’s booster had pulled off the landing on the platform, that would have been historic.

In previous experiments, engineers brought it down softly into the water.

Falcon 9 landing site.
SpaceX
Falcon 9 landing site.

Here’s how the booster was designed to get back down to Earth.

First, fall at a speed of about a mile a minute. Then fire boosters three times in sequence, which Space X describes in colorful terms.

The first boost, called the “boostback burn” turns the bottom of the first stage downward, then the “supersonic retro propulsion burn” cuts the fall speed to about 800 feet per second. Then comes the “landing burn,” when the landing gear legs also push out for the set-down.

By then the booster descends at a speed of about seven feet per second.

Falcon 9 boosters have gone through these phases successfully in two prior tests, SpaceX said. At the end, the rockets tipped sideways and crashed into the ocean, causing damage that made them unusable.

But that was according to plan, SpaceX said.

Setting down with its landing legs onto the platform would have preserved the booster for its possible reuse.

Though it didn’t work out, SpaceX didn’t necessarily expect it to. It had puts the odds of success of this first try at 50% – at best.

For more space and science news, see CNN’s new dedicated page.