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SpaceX CEO Elon Musk explains how Starships will return from orbit

SpaceX's Starship spacecraft will eventually have to survive orbital-velocity reentries, a spectacularly difficult feat for large spacecraft. (NASASpaceflight - bocachicagal)

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In the near future, SpaceX wants to begin putting its first two full-scale Starship prototypes through a series of increasingly challenging test flights, eventually culminating in their first Super Heavy-supported orbital launch attempts.

SpaceX CEO Elon Musk took to Twitter over the last 48 or so hours to answer a number of questions about how exactly Starship is meant to make it through orbital reentries – by far the most strenuous period for the ship and without a doubt the single most challenging engineering problem SpaceX must tackle.

Starship glows from heating as it reenters Earth’s atmosphere in this official render. (SpaceX)

Discussed yesterday on Teslarati, SpaceX technicians began the process of attaching numerous Tesla Model S/X battery packs to a subcomponent that will eventually be installed inside Starship Mk1’s nose, offering a storage capacity of up to 400 kWh. The need for all that power (Crew Dragon relies on a few-kWh battery) is directly related to Starship Mk1’s methods of reentry and recovery, recently described in detail by Elon Musk.

As noted above, ~400 kWh of batteries are needed to power the electric motors that will actuate Starship’s massive control surfaces – two large aft wings and two forward canards/fins. According to Musk, Starship’s “stability is controlled by (very) rapid movement of rear & fwd fins during entry & landing”, meaning that the spacecraft will need to constantly tweak its control surfaces to remain in stable flight.

This official graphic covers Starship’s exotic method of flight and landing. (SpaceX)

By far the biggest challenge SpaceX faces is ensuring that Starship can survive numerous orbital-velocity reentries with little to no wear and tear, a necessity for Starship to be cost-effective. In Low Earth Orbit (LEO), Starship will be traveling no less than 7.8 km/s (Mach 23, 17,500 mph) at the start of atmospheric reentry. In simple terms, the process of slowing from orbital velocity to landing on Earth involves turning the vast majority of that kinetic energy into heat. As Musk noted yesterday, this reality is just shy of unavoidable but there is some flexibility in terms of how quickly one wants to convert that energy into heat.

The fastest route to Earth would involve diving straight into the atmosphere, dramatically increasing peak heating on a spacecraft’s surface to the point that extremely exotic heat shields and thermal protections systems become an absolute necessity. SpaceX wants to find a middle ground with Starship in which the spacecraft uses its aerodynamic control surfaces and body to generate lift, slowly and carefully lowering itself into Earth’s atmosphere over a period of 15+ minutes. Musk notes that this dramatically lessens peak heating at the cost of increasing the overall amount of energy Starship has to dissipate, a bit like cooking something in the oven at 300 degrees for 30 minutes instead of 600 degrees for 10 minutes.

To an extent, Starship’s reentry profile is actually quite similar to NASA’s now-retired Space Shuttle, which took approximately 30 minutes to go from its reentry burn to touchdown. Per the above infographic, it looks like Starship will take approximately 20 minutes from orbit to touchdown, owing to a dramatically different approach once it reaches slower speeds. Originally described by Musk in September 2018 and again in recent weeks, Starship will essentially stall itself until its forward velocity is nearly zero, after which the giant spacecraft will fall belly-down towards the Earth, using its wings and fins to maneuver like a skydiver. The Space Shuttle landed on a runway like a (cement-encased) glider.

This unusual approach allows SpaceX to sidestep the need for huge wings, preventing Starship from wasting far more mass on aerodynamic surfaces it will rarely need. The Space Shuttle is famous for its massive, tile-covered delta wing and the leading-edge shielding that partially contributed to the Columbia disaster. However, it’s a little-known fact that the wing’s size and shape were almost entirely attributable to US Air Force demands for cross-range performance, meaning that the military wanted Shuttles to be able to travel 1000+ miles during reentry and flight. This dramatically constrained the Shuttle’s design and was never once used for its intended purpose.

Space Shuttle Endeavor shows off its main heat shield during an on-orbit inspection in August 2007. (NASA)

SpaceX thankfully doesn’t have its own “US Air Force” stand-in making highly consequential demands (aside from Elon Musk ?). Instead, Starship will continue the SpaceX tradition of vertical landing, falling straight down – a bit like a skydiver (or a brick) – on its belly and flipping itself over with fins and thrusters for a propulsive vertical landing. In this way, Starship doesn’t have to be a brick forced to fly, like the Shuttle was – it just needs to be able to stably fall and quickly flip itself from a horizontal to vertical orientation.

Additionally, Starship is built almost entirely out of steel, whereas the Shuttle relied on an aluminum alloy and needed thermal protection over every square inch of its hull. Steel melts at nearly twice the temperature of the Shuttle’s alloy, meaning that Starship will (hopefully) be able to get away with nothing more than ceramic tiles on its windward half, saving mass, money, and time. Once Starship completes its first 20 km (12.5 mi) flight test(s), currently scheduled no earlier than mid-October, SpaceX will likely turn its focus on verifying Starship’s performance at hypersonic speeds, ultimately culminating in its first orbital-velocity reentries.

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Eric Ralph is Teslarati's senior spaceflight reporter and has been covering the industry in some capacity for almost half a decade, largely spurred in 2016 by a trip to Mexico to watch Elon Musk reveal SpaceX's plans for Mars in person. Aside from spreading interest and excitement about spaceflight far and wide, his primary goal is to cover humanity's ongoing efforts to expand beyond Earth to the Moon, Mars, and elsewhere.

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Elon Musk

Elon Musk sheds two new bits of detail on Starship after 13th test launch

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Credit: SpaceX

Elon Musk shed two new bits of detail on Starship following its 13th test launch, which was an overwhelming success.

SpaceX launched Starship for the 13th time last Friday after two delays: one on Monday when several Raptor engines did not ignite, and another on Thursday due to unfavorable weather conditions in Starbase, Texas.

The launch was overwhelmingly successful. SpaceX was able to complete a necessary test of the heat shield tiles by increasing the acceleration of Starship from launch throughout the flight; 20 Starlink v3 satellites were released with no issue; the Super Heavy Booster landed safely in the Gulf of America, Ship successfully reignited engines while in space; and it also splashed down without incident in the Indian Ocean.

SpaceX Starship just nailed something it’s never done before

Nevertheless, more details are coming out about Starship, and Musk is doing the talking.

Starship Will Be Retrieved in the Ocean

Musk revealed on Tuesday night that Starship would be recovered by a ship in the Indian Ocean. SpaceX routinely tries to recover Starship after splashdown in an effort to find out more about the flight by examining the spacecraft afterward.

This helps engineers find out more about why things might have happened, allows them to examine any potential damage or anomalies that might have occurred, and increases the chances of an even more successful flight next time thanks to the additional information recovered.

Ship Could Have Been Caught by Tower Arms, Musk claims

Musk has already indicated that SpaceX will plan to attempt a catch of Starship with the 14th test flight. While this would be a major accomplishment, it would be an expected next step, considering the fact that the Super Heavy Booster has already been caught by the chopsticks on numerous occasions.

A ship catch would be a great indication of where SpaceX stands in terms of reusability and launch cadence. A successful catch with relatively no incidents would be a good sign that SpaceX is nearing a more frequent launch of Starship, but also that the reusability of the massive rocket would be something many would expect in the near future.

It is a necessity to make life multiplanetary.

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Elon Musk

Elon Musk updates the SpaceX timeline for Mars

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Rendering of a colonized Mars by way of SpaceX
Rendering of a colonized Mars by way of SpaceX

Elon Musk has updated his timeline for when humans will walk on Mars and for when ships will simply get there.

The objective of getting to Mars has been one of Musk’s biggest goals since becoming a serial entrepreneur and realizing that time on Earth is limited. Musk has said several times he hopes to die on Mars, and not by impact.

Musk now believes that people will be on Mars in “roughly 5 to 7 years.” He said that a Mars lander will get there “a few years sooner.”

The response from Musk comes after NASA Administrator Jared Isaacman said that SpaceX’s biggest priority is the Moon and not Mars. Because of this, Isaacman conceded that he believes nuclear power and propulsion investments will provide “potentially the pathway with the fewest miracles required to put four people on Mars in the next 10 to 15 years.”

Of course, this is what NASA can do through taxpayer funding and nuclear investments, he added.

Musk’s grand ambitions are much more optimistic than most, and it is certainly a double-edged sword. This is not the first time timelines for Mars have been somewhat lofty, especially to those normal thinkers like you and me, not super geniuses like Musk.

SpaceX Board has set a Mars bonus for Elon Musk

In fact, the SpaceX and Tesla frontman has said on at least a dozen occasions that we could be on Mars in the coming years. Musk said 2020 would be the big year as early as 2009. In 2020, he was “highly confident” of a landing in 2026, and had even said 2024 in a best-case scenario.

The point is, the range has varied, and it’s anyone’s guess when we’ll get there. This latest adjustment to the timeline is typical of Musk, and while the Moon has seemingly taken priority over Mars, it is still worth mentioning that the ultimate goal is to make life multiplanetary, and it starts potentially with the Red Planet.

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Investor's Corner

SpaceX gets an absolutely crazy price target after rough IPO

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Credit: SpaceX

SpaceX (NASDAQ: SPCX) got an absolutely crazy price target rating from Raymond James after the company experienced a tough first few weeks following its Initial Public Offering (IPO).

Despite the tumultuous start, SpaceX has plenty of believers, and the company’s massively successful Starship launch last Friday, its 13th test flight of the massive rocket, went so smoothly that Raymond James analysts pushed its price target on the company to roughly 7 times its current trading level.

SpaceX Starship just nailed something it’s never done before

The firm officially put a “Strong Buy” rating and an $800 price target on the stock. It currently trades at around $113. Its all-time high is $225.64, reaching this trading level shortly after shares first went public.

Raymond James’ price target is tied to the firm’s confidence after Starship’s 13th test flight. Analysts at the firm said it was an incremental step that reduces engineering risks, citing the widely successful heat shield test that CEO Elon Musk recently detailed, the smooth deployment of Starlink V3 satellites, and a successful in-space engine relight.

SpaceX also managed to see Starship splash down safely in the Indian Ocean, while the Super Heavy Booster fell down to the Gulf of America with no incidents.

It is interesting to see these launches have such a tremendous impact on the stock and what investors think of it. After SpaceX initially delayed the Starship launch last week, shares fell tremendously. Most probably did not realize that the stand-down is a standard practice, especially if everything is not perfect.

The mission was initially aborted due to an issue with Raptor engines. This was resolved, and Starship launched last Friday after another delay on Thursday, which was caused by weather.

Now that analysts have seen what SpaceX launches are capable of and how impressive the feat is, firms are adjusting their price targets accordingly, making it known that they have high expectations for the space exploration company.

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