SpaceX's Grasshopper: Reusable Rocket Prototype — **On Oct. 7, 2013, SpaceX's Grasshopper rocket climbed 2,441 feet (744 meters) into the air before safely landing back on its launch pad in McGregor, Texas.**
**Credit: SpaceX**

Grasshopper was a reusable vertical-takeoff-and-landing rocket prototype tested by the company Space Exploration Technologies (SpaceX) in preparation for more ambitious launches. After progressively higher hops and pinpoint landings in two years, SpaceX wrapped up the program in 2013 to move resources into the Falcon 9 rocket.

The first stage of several versions of the Falcon 9 rocket have splashed down successfully, and SpaceX is now aiming to land the rocket on an automated barge. Several barge-landing attempts have been made since 2015, but the rocket has not survived any of them yet. SpaceX, however, says that it is getting close to success and that the technology is possible to make the pinpoint landing happen.

Grasshopper was the first stage of SpaceX's Falcon 9, which the company still uses today for the Dragon cargo spacecraft flights to the station. Test flights ran between 2012 and 2013 and were successful, according to SpaceX.

First announced in September 2011, Grasshopper was one piece of SpaceX's desire to make a fully reusable system that will fly cargo and people to and from space. Traditionally, rockets have been considered "throwaway" items, with few exceptions (such as the space shuttle's external solid rocket boosters.)

SpaceX's vision then included fly-back first and second stages on the rocket as well as a spacecraft that can land on land. The Dragon spacecraft currently lands on the water, similar to how the Apollo spacecraft used to do. The human-rated version of the spacecraft will also initially land on water, but later versions are expected to reach solid ground with the stabilizing help of Dragon's SuperDraco engines.

"We will see if this works," SpaceX CEO and founder Elon Musk said when announcing Grasshopper. "And if it does work, it'll be pretty huge."

SpaceX's reusable Grasshopper rocket prototype rises skyward from its McGregor, Texas launch pad during a June 14, 2013 test flight that reached 1,066 feet (325 meters) before descending back to Earth. This still was taken from a video recorded by a small unmanned hexacopter.
**Credit: SpaceX**

The six-foot flight

The first test flight of the rocket took place Sept. 21, 2012, when Grasshopper made a quick six-foot (1.8-meter) jump up and down at SpaceX's test facility in McGregor, Texas. With each subsequent flight, the company then tried to shoot a bit higher or do something different.

The next test in November saw the rocket go about 18 feet (5.5 m) in the air, and then a big test in December saw the rocket soar more than 130 feet (39.6 m) high.

Over several test flights in 2013, Grasshopper demonstrated an ability to fight back against wind gusts, as well as to move sideways in the air to its target. It also flew several hundred feet high on a few occasions. The company filmed the rocket flights from the air using autonomous aircraft, providing high-definition views that it uploaded to the Web for sharing.

Among Grasshopper's notable flights was a jump in April 2013 that saw the 10-story vehicle fly 820 feet (250 m) high. In June 2013, Grasshopper leaped 1,066 feet (325 m) and made a near-perfect landing. A subsequent flight test in August included a 100-foot lateral or sideways maneuver before the rocket touched down safely on the ground.

The program capped off Oct. 7, 2013, when the rocket flew 2,441 feet (744 m) into the air, making a flawless takeoff and landing in a flight that lasted about 79 seconds. SpaceX then decided to retire the prototype in favor of using the personnel and money for other programs, notably the Falcon 9 rocket.

https://youtu.be/ygFN1isnz_Y

SpaceX's F9R Reusable Rocket Launches on 1st Test Flight | Video

https://youtu.be/sSF81yjVbJE

SpaceX Reusable Launch System

Falcon landing attempts

On April 18, 2014, SpaceX made a world-first controlled splashdown of the first stage of a Falcon 9, during a Dragon spacecraft resupply run to the International Space Station.

After several water landings, SpaceX tried to make a world-first attempt for a barge landing in January 2015 during a cargo flight to the International Space Station. The first landing made it on target, but the rocket landed hard enough to damage some of the support equipment on the ship, according to Musk.

Another attempt was called off in February 2015 when on landing day, the barge was facing 3-meter waves (almost 10 feet) and also had a malfunction in one of its four thrusters, making it tough to stabilize the ship. SpaceX instead elected for a water landing, which it pulled off successfully.

SpaceX also made hard landings on the ship in rocket flights in April 2015 and January 2016. The first malfunction was partly traced to a problem with the control system, while the second failed because one of the landing legs did not latch. SpaceX did, however, land the rocket's first stage safely on land (near its launch site at the Kennedy Space Center) in a December 2015 flight.

Musk's ultimate goal is to establish a colony on Mars by bringing the cost of spaceflight down as much as he can. Launch costs are considered one of the toughest things to overcome, since it takes a lot of fuel and velocity for a rocket to fight against Earth's gravity to bring items into space.

What Is a 'Morning Star,' and What Is an 'Evening Star'? — Skywatcher Shawn Malone took this photo of two "evening stars," Venus and Jupiter, in Eagle Harbor, Michigan, on March 10, 2012. Whether a planet qualifies as a "morning star" or an "evening star" can vary throughout the year.
**Credit: Shawn Malone**

I received an interesting inquiry recently from a woman who wanted to know the meaning of the terms "morning stars" and "evening stars."

"I mean, they're not stars … they're planets, right?" she asked. "So why do we call them stars? And is a morning star only visible in the morning, like at the crack of dawn, or at other times as well? Hope you can clear this up for me because I'm totally confused!"

Here is an explanation for what qualifies as a "morning star" and an "evening star." [Night Sky: Visible Planets, Moon Phases & Events, February 2016]

It began with Venus

Originally, the terms "morning star" and "evening star" applied only to the brightest planet of all, Venus. Far more dazzling than any of the actual stars in the sky, Venus does not appear to twinkle, but instead glows with a steady, silvery light. The fact that Venus was a "wandering star" soon became obvious to ancient skywatchers, who noticed its motion relative to the background stars, going from the eastern sky in the morning to the western sky in the early evening. Nicolas Camille Flammarion, a noted French astronomer in the late 19th and early 20th century, referred to Venus as "The Shepherd's Star." I myself like to refer to Venus as the "night light of the sky." So, it's easier to understand the origin of the terms "evening star" and "morning star" if we only considered Venus.

Of course, Venus is not the only wandering "star" in the sky; there are four others that are also visible to the unaided eye (five, if you include Uranus, which is barely perceptible without any optical aid on dark, clear nights). The difference is that, with the possible exception of Jupiter and, on rare occasions, Mars, none of the others stands out in the same manner as Venus. Nonetheless, somewhere in the distant past, "morning star" and "evening star" became plural in order to account for the four other planets.

When an evening star is branded as a morning star

This upcoming week, there are officially no evening stars, only morning stars.

But the distinction between these terms is not very precise. As an example, let me call attention to the fact that rising in the east this week, between 7:30 p.m. and 8 p.m., is the planet Jupiter. It will attain its highest point in the southern sky between 1:30 a.m. and 2 a.m. local time, and will still be visible, sinking in the western sky at dawn. The giant planet is thus ideally situated for observations of its changing cloud bands and four big satellites for much of the night.

The fact that Jupiter is already above the horizon during "prime-time" evening hours should qualify it for evening-star status. By the same reasoning, it is a morning star as well!

The next planet due to come into view will be Mars, which rises soon after 12:30 a.m. local time and is crossing the southern meridian by sunrise. So, the Red Planet must be a morning star.

With Mercury and Venus, there is never such ambiguity, as they are never very far from the sun in the sky. In fact, in the pre-Christian era, both of these planets had dual identities — two names — as initially, it was not realized that they alternately appeared on one side of the sun and then on the other. Mercury was called Apollo when it shone as a morning star, and was called Mercury when it appeared in the evening sky. Venus was Phosphorus in the morning and Hesperus in the evening. We can thank Pythagoras around the 5th century B.C. for pointing out that Hesperus and Phosphorus were really one in the same.

Because they orbit the sun more closely than Earth does, Mercury and Venus are called "inferior" planets. Elongation refers to the angle between the sun and a planet, as seen from Earth. In general, when Mercury or Venus has a western elongation from the sun, it is a morning star; with an eastern elongation, it is an evening star.

Different planets may appear together in the morning or evening sky, depending on their location relative to Earth and the sun. Jim Gemmel of Warrenton, Virginia, took this picture of Venus and Jupiter on March 10, 2012.
**Credit: Jim Gemmel**

Transition at opposition

This rule can be extended to the planets that orbit the sun beyond our own orbit — the so-called "superior" planets, Mars, Jupiter and Saturn. When a superior planet is in the same spot in the sky as the sun, it is at conjunction. While a superior planet is moving from conjunction with the sun to just a day prior to its opposition (when it is directly opposite the sun in the sky), it is a morning star. At opposition, it rises approximately when the sun sets and sets as the sun rises. From then on, it is branded as an evening star, rising or already in the sky as daytime ends.

So, going by this nomenclature, Jupiter will arrive at opposition and will become an evening star on March 8, Mars on May 22 and Saturn on June 3. Until then, they are all morning stars, even though, as we have already seen, Jupiter — and, eventually, Mars and Saturn — will be readily visible in the evening sky well before their opposition dates.

Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for Natural History magazine, the Farmer's Almanac and other publications, and he is also an on-camera meteorologist for News 12 Westchester, New York. Follow us @Spacedotcom, Facebook or Google+. Originally published on Space.com.