Elon Musk is well-known for his ability to create a media sensation. Scarcely a week goes by that the founder of SpaceX and Tesla doesn’t have an announcement or update to make – often via his social media outlet of choice, twitter. And as a major figure in the NewSpace industry, anything he says is guaranteed to elicit reactions (both critical and hopeful) from the space community and general public.
Just last week (on Monday, Sept. 17th), he revealed new information about the Big Falcon Rocket (BFR) and who its first passenger would be when it conducts its first lunar mission (which is planned for 2023). And on Friday (Sept. 21st), Musk shared some updated plans on when a SpaceX Martian colony could be established. According to the tweet he posted, his company could build a base on Mars (Mars Base Alpha) as early as 2028.
Ever since Elon Musk announced the latest addition to the SpaceX rocket family back in September of 2016, the general public and space community has been eagerly awaiting updates on its progress. Known as the Big Falcon Rocket (BFR), this massive launch vehicle is central to Musk’s plan of conducting space tourism with flights into orbit and to the Moon. It is also intrinsic to his vision of sending astronauts and colonists to Mars.
Already this year, Musk announced that the BFR could be ready to make orbital launches by 2020 and showed the Main Body Tool that would build the BFR. And on Monday, September 17th – during a press conference at SpaceX headquarters in California – Musk announced who the first passenger aboard the BFR will be as it conducts its first lunar mission – the Japanese fashion innovator and globally recognized art curator, Yusaku Maezawa.
When Elon Musk of SpaceX tweets something interesting, it generates a wave of excitement. So when he tweeted recently that SpaceX might be working on a way to retrieve upper stages of their rockets, it set off a chain of intrigued responses.
SpaceX will try to bring rocket upper stage back from orbital velocity using a giant party balloon
SpaceX has been retrieving and reusing their lower stages for some time now, and it’s lowered the cost of launching payloads into space. But this is the first hint that they may try to do the same with upper stages.
Twitter responders wanted to know exactly what SpaceX has in mind, and what a “giant party balloon” might be. Musk hasn’t elaborated yet, but one of his Twitter followers had something interesting to add.
If you're proposing what I think you are, an ultra low ballistic entry coefficient decelerator, then you and @SpaceX should come see what we have at the @UofMaryland . We've been working on this for awhile and just finished some testing pic.twitter.com/nJBvyUnzaK
Universe Today contacted Mr. Kupec to see if he could help us understand what Musk may have been getting at. But first, a little background.
An “ultra low ballistic entry coefficient decelerator” is a bit of a mouthful. The ballistic coefficient measures how well a vehicle can overcome air resistance in flight. A high ballistic coefficient means a re-entry vehicle would not lose velocity quickly, and would reach Earth at high speeds. An ultra low ballistic entry coefficient decelerator would lose speed quickly, meaning that a vehicle would be travelling at low, subsonic speeds before reaching the ground.
To recover an upper stage booster, low speeds are desirable, since they generate less heat. But according to Kupec, there’s another problem that must be overcome.
“What happens when these things slow down to landing velocities? If your center of gravity is offset significantly behind your center of drag, as would be the case with a returning upper stage, it can get unstable. If the center of gravity of the re-entry vehicle is too high, it can become inverted, which is obviously not desirable.”
So the trick is to lower the speed of the re-entry vehicle to the point where the heat generated by reentry isn’t damaging the booster, and to do it without causing the vehicle to invert or otherwise become unstable. This isn’t a problem for the main stage boosters that SpaceX now routinely recovers; they have their own retro-rockets to guide their descent and landing. But for the upper stage boosters, which reach orbital velocities, it’s an obstacle that has to be overcome.
“My research is specifically focused on how high you can push the center of gravity and still maintain the proper flight configuration,” said Kupec.
But what about the “giant party balloon” that Musk tweeted about?
Musk could be referring, in colorful terms, to what’s called a ballute. The word is a combination of the words balloon and parachute. They were invented in the 1950’s by Goodyear Aerospace. They can arrest the descent of entry vehicles and provide stability during the descent.
“…the balloon would have to be 120 ft. in diameter, and made of a high-temperature fabric…” – Professor Dave Akin, University of Maryland
Universe Today contacted Professor Dave Akin of the University of Maryland for some insight into Musk’s tweet. Professor Akin has been working on reentry systems for over 2 decades.
In an e-mail exchange, Professor Akin told us, “There have been concepts proposed for deploying a large balloon on a cable that is towed behind you on entry. The balloon lowers your ballistic coefficient, which means you decelerate higher in the atmosphere and the heat load is less.” So the key is to scrub your speed before you get closer to Earth, where the atmosphere is thicker and generates more heat.
But according to Professor Akin, this won’t necessarily be easy to do. “To get the two orders of magnitude reduction in ballistic coefficient that Elon has been talking about the balloon would have to be 120 ft. in diameter, and made of a high-temperature fabric, so it’s not going to be all that easy.”
But Musk’s track record shows he doesn’t shy away from things that aren’t easy.
Retrieving upper rocket stages isn’t all about lowering launch costs, it’s also about space junk. The European Space Agency estimates that there are over 29,000 pieces of space junk orbiting Earth, and some of that junk is spent upper stage boosters. There have been some collisions and accidents already, with some satellites being pushed into different orbits. In 2009, the Iridium 33 communications satellite and the defunct Russian Cosmos 2251 communications satellite collided with each other, destroying both. If SpaceX can develop a way to retrieve its upper stage boosters, that means less space junk, and fewer potential collisions.
There’s a clear precedent for using balloons to manage reentry. With people like Professor Akin and Quinn Kupec working on it, SpaceX won’t have to reinvent the wheel. But they’ll still have a lot of work to do.
Musk tweeted one other thing shortly after his “giant party balloon” tweet:
In September of 2016, Elon Musk announced the latest addition to the SpaceX rocket family. Known then as the Interplanetary Transport System (ITS) – now know as the Big Falcon Rocket (BFR) – this massive launch vehicle is central to Musk’s vision of sending astronauts and colonists to Mars someday. Since that time, the space community has eagerly waited for any news on how the preparations for this rocket are going.
Musk further inflamed people’s anticipation by recently announcing that the BFR would be ready to conduct orbital flights by as early as 2020. While admittedly an optimistic deadline, Musk indicated that his company was building the presently building the ship. And according to a recent post on Musk’s Instagram account, a key component (the main body tool) for making the BFR interplanetary spaceship has just been completed.
It is important to note, however, that what is being shown here is not actually a part of the rocket. As Ryan Whitwam of Extreme Tech noted, what we are seeing in the post is a tool “that SpaceX will use to fabricate the rocket from carbon fiber composite materials that are lighter than traditional materials. Flexible resin sheets of carbon fiber will be layered on the tool and then heated to cure them. After heating, you’re left with a solid section of rocket fuselage. It’s essentially a carbon fiber jig.”
Nevertheless, from the size of the tool itself, one gets a pretty clear idea of how large the final rocket will be. SpaceX chose to illustrate the scale of the tool by placing a Tesla next to it for scale. For some additional perspective, consider the cherry Tesla Roadster (driven by Starman) SpaceX launched with the Falcon Heavy‘s maiden flight.
Whereas the payload capsule was barely large enough to house it, this car looks like it could fit inside any rocket turned out by this tool easily, and with plenty of room to spare. And while cars are not exactly the BFR’s intended payload, it is good to know that it will be no slouch in that department!
When completed, the BFR will be the largest and most powerful rocket in the SpaceX rocket family. According to the company’s own specifications, it will measure 106 meters (348 ft) in height and 9 meters (30 ft) in diameter and will be able to deliver a payload of 150,000 kg (330,000 lb) to Low-Earth Orbit (LEO) – almost two and a half times the payload of the Falcon Heavy (63,800 kg; 140,660 lb).
And as Musk indicated during an interview with Jonathon Nolan at the 2018 South by Southwest Conference (SXSW) in Austin, Texas, it will even outpace the rockets that won the Space Race for the US:
“This a very big booster and ship. The liftoff thrust of this would be about twice that of a Saturn V (the rockets that sent the Apollo astronauts to the Moon). So it’s capable of doing 150 metric tons to orbit and be fully reusable. So the expendable payload is about double that number.”
Once completed, Musk hopes to see the BFR performing service missions to Low-Earth Orbit (LEO), the International Space Station, to the Moon, and – of course – to Mars. In addition to sending colonists there as early as the next decade, Musk has also expressed interest in using the BFR to conduct space tourism – flying passengers in luxury accommodations to the Red Planet and back.
In the end, it is clear that Musk and the company he founded for the purpose of reigniting space exploration are determined to make all of this happen. In the coming years, it will be interesting to see how far and how fast they progress.
About a week ago, it was revealed that the roughly 50 million Facebook profiles were harvested by Cambridge Analytica. This private data firm, which worked with Donald Trump’s election team and the Brexit campaign, reportedly used this data build a software program that could predict and influence voter choices. Since that time, Facebook stock has taken a serious hit, investigations have been mounted, and CEO Mark Zuckerberg himself has come under fire.
In addition, this revelation has led many Facebook users to reconsider their privacy settings or cancel their accounts. One such person is Elon Musk. In a move that could prove rather harmful for the social media giant, Musk recently responded to the news by deleting the official Facebook pages for Tesla and SpaceX. And in a rather ironic twist, the announcement came via another social media giant – Elon Musk’s twitter account.
It all began after Musk responded to a tweet posted by Brian Acton, the famed programmer and entrepreneur who co-founded WhatsApp and is the founder of Signal (an encrypted communications app). In what was clearly an act of jest, he responded to Acton’s statement (“It is time”) and use of the trending hashtag (#deletefacebook), by inquiring “What’s Facebook?”
Naturally, no one was buying it, given that SpaceX and Facebook – and their respective CEOs) – have a rather colorful history of business relations. These include the failed launch that took place in September of 2016, where a Falcon 9 carrying a Israeli telecommunications satellite (which would have also been used by Facebook) exploded on the launch pad.
In response to the news, Zuckerberg posted a statement on Facebook that placed the blame for the failed launch squarely on Musk’s company:
“As I’m here in Africa, I’m deeply disappointed to hear that SpaceX’s launch failure destroyed our satellite that would have provided connectivity to so many entrepreneurs and everyone else across the continent.”
This old grudge was also raised on Twitter amidst the discussion about Facebook’s data breach, with a user reminding everyone about the incident. Musk brushed this aside, tweeting, “Yeah, my fault for being an idiot. We did give them a free launch to make up for it and I think they had some insurance.”
This led to a challenge being issued to Musk, where users wrote him and urged him to delete his company’s accounts. In what was arguably an attempt to keep the joke going, Musk responded by indicating that he didn’t know these accounts existed. He did, however, also promise to remove the accounts forthwith.
And it appears that Musk was true to his word. While SpaceX and Tesla still have Facebook pages and show up in searches, the official accounts appear to be gone. Musk chose to maintain the company’s official Instagram account though, and used the opportunity to once again stress that he had little use for Facebook:
“Instagram’s probably ok imo, so long as it stays fairly independent. I don’t use FB & never have, so don’t think I’m some kind of martyr or my companies are taking a huge blow. Also, we don’t advertise or pay for endorsements, so … don’t care.”
Well, martyr or not, Musk appears to have put his money where his mouth is. And of course, his twitter feed is still going strong and there is no indication he plans on turning that off anytime soon! And whether this was intended as as slight to Zuckerberg or a sincere expression of indifference, it is likely that Musk’s move could prompt more users to delete their accounts.
But of course, the social media giant will survive. And given Zuckerberg‘s and Musk‘s competing visions to provide global broadband internet access using satellites, its a certainty that the two entrepreneurs are not done with each other!
Elon Musk has a reputation for pushing the envelop and making bold declarations. In 2002, he founded SpaceX with the intention of making spaceflight affordable through entirely reusable rockets. In April of 2014, his company achieved success with the first successful recovery of a Falcon 9 first stage. And in February of this year, his company successfully launched its Falcon Heavy and managed to recover two of the three boosters.
But above and beyond Musk’s commitment to reusability, there is also his longer-term plans to use his proposed Big Falcon Rocket (BFR) to explore and colonize Mars. The topic of when this rocket will be ready to conduct launches was the subject of a recent interview between Musk and famed director Jonathon Nolan, which took place at the 2018 South by Southwest Conference (SXSW) in Austin, Texas.
During the interview, Musk reiterated his earlier statements that test flights would begin in 2019 and an orbital launch of the full BFR and Big Falcon Spaceship (BFS) would take place by 2020. And while this might seem like a very optimistic prediction (something Musk is famous for), this timeline does not seem entirely implausible given his company’s work on the necessary components and their success with reusability.
As Musk emphasized during the course of the interview:
“People have told me that my timelines have historically been optimistic. So I am trying to re-calibrate to some degree here. But I can tell what I know currently is the case is that we are building the first ship, the first Mars or interplanetary ship, right now, and I think we’ll probably be able to do short flights, short sort of up-and-down flights probably in the first half of next year.”
To break it down, the BFR – formerly known as the Interplanetary Transport System – consists of a massive first stage booster and an equally massive second stage/spaceship (the BFS). Once the spacecraft is launched, the second stage would detach and use its thrusters to assume a parking orbit around Earth. The first stage would then guide itself back to its launchpad, take on a propellant tanker, and return to orbit.
The propellant tanker would then attach to the BFS and refuel it and return to Earth with the first stage. The BFS would then fire its thrusters again and make the journey to Mars with its payload and crew. While much of the technology and concepts have been tested and developed through the Falcon 9 and Falcon Heavy, the BFR is distinct from anything else SpaceX has built in a number of ways.
For one, it will be much larger (hence the nickname, Big F—— Rocket), have significantly more thrust, and be able carry a much larger payload. The BFR’s specifications were the subject of a presentation Musk made at the 68th International Astronautical Congress on September 28th, 2017, in Adelaide, Australia. Titled “Making Life Interplanetary“, his presentation outlined his vision for colonizing Mars and presented an overview of the ship that would make it happen.
According to Musk, the BFR will measure 106 meters (348 ft) in height and 9 meters (30 ft) in diameter. It will carry 110 tons (~99,700 kg) of propellant and will have an ascent mass of 150 tons (~136,000 kg) and a return mass of 50 tons (~45,300 kg). All told, it will be able to deliver a payload of 150,000 kg (330,000 lb) to Low-Earth Orbit (LEO) – almost two and a half times the payload of the Falcon Heavy (63,800 kg; 140,660 lb)
“This a very big booster and ship,” said Musk. “The liftoff thrust of this would be about twice that of a Saturn V (the rockets that sent the Apollo astronauts to the Moon). So it’s capable of doing 150 metric tons to orbit and be fully reusable. So the expendable payload is about double that number.”
In addition, the BFR uses a new type of propellant and tanker system in order to refuel the spacecraft once its in orbit. This goes beyond what SpaceX is used to, but the company’s history of retrieving rockets and reusing them means the technical challenges this poses are not entirely new. By far, the greatest challenges will be those of cost and safety, since this will be only the third reusable second stage spacecraft in history.
The other two consist of the NASA Space Shuttles, which were officially retired in 2011, and the Soviet/Russian version of the Space Shuttle known as the Buran spacecraft. While the Buran only flew once (an uncrewed flight that took place in 1988), it remains the only Russian reusable spacecraft to have even been built or flown.
Where costs are concerned, the Space Shuttle Program provides a pretty good glimpse into what Musk and his company will be facing in the years ahead. According to estimates compiled in 2010 (shortly before the Space Shuttle was retired), the program cost a total of about $ 210 billion USD. Much of these costs were due to maintenance between launches and the costs of propellant, which will need to be kept low for the BFR to be economically viable.
Addressing the question of costs, Musk once again stressed how reusability will be key:
“What’s amazing about this ship, assuming we can make full and rapid reusability work, is that we can reduce the marginal cost per flight dramatically, by orders of magnitude compared to where it is today. This question of reusability is so fundamental to rocketry, it is the fundamental breakthrough that’s needed.”
As an example, Musk compared the cost of renting a 747 with full cargo (about $500,000) and flying from California to Australia to buying a single engine turboprop plane, – which would run about $1.5 million and cannot even reach Australia. In short, the BFR relies on the principle that it costs less for an entirely reusable large spaceship to make a long trip that it does to launch a single rocket on a short trip that would never return.
“A BFR flight will actually cost less than our Falcon 1 flight did,” he said. “That was about a 5 or 6 million dollar marginal cost per flight. We’re confident the BFR will be less than that. That’s profound, and that is what will enable the integration of a permanent base on the Moon and a city on Mars. And that’s the equivalent of like the Union Pacific Railroad, or having ships that can quickly cross the oceans.”
Beyond manufacturing and refurbishing costs, the BFR will also need to have an impeccable safety record if SpaceX is to have a hope of making money from it. In this respect, SpaceX hopes to follow a development process similar to what they did with the Falcon 9. Before conducting full launch tests to see if the first stage of the rocket could safely make it to orbit and then be retrieved, the company conducted short hop tests using their “Grasshopper” rocket.
According to the timeline Musk offered at the 2018 SXSW, the company will be using the spaceship that is currently being built to conduct suborbital tests as soon as 2019. Orbital launches, which may include both the booster and the spaceship, are expected to occur by 2020. At present, Musk’s earlier statements that the first flight of the BFR would take place by 2022 and the first crewed flight by 2024 still appear to be on.
For comparison, the Space Launch System (SLS) – which is NASA’s proposed means of getting to Mars – is scheduled to conduct its first launch in 2019 as well. Known as Exploration Mission 1 (EM-1), this launch will involve sending an uncrewed Orion capsule on a trip around the Moon. EM-2, in which a crewed Orion capsule will delver the first module of the Lunar Orbital Platform-Gateway (LOP-G, formerly the Deep Space Gateway) to lunar orbit, will take place in 2022.
The ensuing missions will consist of more modules being delivered to lunar orbit to complete construction of the LOP-G, as well as the Deep Space Transport (DST). The first interplanetary trip to Mars, Exploration Mission 11 (EM-11), won’t to take place until 2033. So if Musk’s timelines are to be believed, SpaceX will be beating NASA to Mars, both in terms of uncrewed and crewed missions.
As for who will be enabling a permanent stay on both the Moon and Mars, that remains to be seen. And as Musk emphasized, he hopes that by showing that creating an interplanetary spaceship is possible, agencies and organizations all over the planet will mobilize to do the same. For all we know, the creation of the BFR could enable the creation of an entire fleet of Interplanetary Transport Systems.
The South by Southwest Conference began on Friday, March 9th and will continue until Sunday, March 18th. And be sure to check out the video of the interview below:
The launch of the Falcon Heavy , which took place on Feb. 6th, 2018, was an historic event. After years of preparation, SpaceX successfully launched the heaviest vehicle in its arsenal, which has a lift capacity that is over twice as much as the next heaviest rocket (the United Launch Alliance’s Delta IV Heavy). The launch also demonstrated SpaceX’s commitment to reusability, where two of the three cores were recovered afterwards.
In addition, the launch was a media frenzy as the heavy rocket deployed some very unusual cargo – a Tesla Roadster with Starman (an empty spacesuit) in the driver’s seat. In honor of this event, the company has released a video that showcases the highlights of the launch. Consistent with the theme of the launch, the video was set to David Bowie’s 1971 hit “Life on Mars”, and is quite emotional to watch!
The video begins by showing the crowds assembled outside of SpaceX’s launch site at Space Complex 39A at Cape Canaveral, Florida. We then see Elon Musk’s Tesla Roadster and Starman being loaded aboard the Falcon Heavy payload capsule. What follows is the rollout of the Falcon Heavy at Cape Canaveral, its deployment on the launch pad, and the rocket blasting off.
This is where things get emotional as Bowie’s song hits a crescendo and people on the ground and in the launch complex celebrate the successful launch. We are also treated to some footage of Starman and the Roadster being deployed once they reach orbit. As Starman floats in full view of Earth, we also see the successful recovery of two of the Falcon 9 cores, and the crashing at sea of the third.
While the video manages to cover all the major aspects of the launch, the real focus is definitely on the people who witnessed the event. As the video plays, you can see the anticipation and hope as the rocket is preparing for launch and the sense of elation that came from its success. This is in keeping with Elon Musk’s vision for SpaceX, which he founded in 2002 to inspire public interest in renewed space exploration.
Why Falcon Heavy & Starman?
Life cannot just be about solving one sad problem after another. There need to be things that inspire you, that make you glad to wake up in the morning and be part of humanity. That is why we did it. We did for you. https://t.co/5STO7q4wro
“Life cannot just be about solving one sad problem after another. There need to be things that inspire you, that make you glad to wake up in the morning and be part of humanity. That is why we did it. We did for you.”
Of course, one can’t forget how the launch also signaled that SpaceX is one step closer to achieving Musk’s other dream – which is to reduce the cost associated with space launches by making rockets fully reusable and restoring domestic launch capability to the United States. Now that SpaceX is capable of lifting 64 metric tons (141,000 lbs), NASA won’t have to depend on Roscosmos to send crews and heavy payloads into orbit much longer.
When visionary entrepreneur Elon Musk founded SpaceX in 2002, he did so with the intention of rekindling human space exploration and sending humans to Mars. Intrinsic to this vision was the reduction of costs associated with individual launches, which has so far been focused on the development of reusable first-stage rockets. However, the company recently announced that they are looking to make their rocket’s payload fairings reusable as well.
The payload fairing is basically the disposable shell at the top of the rocket that protects the cargo during launch. Once the rocket reaches orbit, the fairings falls away to release the payload to space and are lost. But if they could be retrieved, it would reduce launch cost by additional millions. Known as “Mr. Steven”, this new retrieval system consists of a platform ship, extended arms, and a net strung between them.
Mr. Steven is not unlike SpaceX’s Autonomous Spaceport Drone Ships (ASDS), which are used to retrieve first stage rocket boosters at sea. SpaceX has two operational drone ships, including Just Read the Instructions – which is stationed in the Pacific to retrieve launches from Vandenberg – and Of Course I Still Love You, which isstationed in the Atlantic to retrieve launches from Canaveral.
Recently, Teslarati’s Pauline Acalin captured some photographs of Mr. Steven while it was docked on the California coast near Vandenberg Air Force Base, where it preparing to head out to sea in support of the latest Falcon 9 launch. Known as the PAZ Mission, this launch will place a series of Spanish imaging satellites in orbit, as well as test satellites that will be part of SpaceX’s plan to provide broadband internet service.
Originally scheduled for Wednesday, February 21st, the launch was scrubbed due to strong upper level winds. It is currently scheduled to take place at 6:17 a.m. PST (14:17 UTC) on Thursday, February 22nd, from Space Launch Complex 4 East (SLC-4E) at the Vandenburg Air Force Base. After the cargo is deployed to orbit, the fairings will fall back slowly to Earth thanks to a set of geotagged parachutes.
These chutes will guide the fairings down to the Pacific Ocean, where Mr. Steven will sail to meet them. The fairings, if all goes as planned, will touch down gently into the net and be recovered for later use. In March of 2017, SpaceX successfully recovered a fairing for the first time, which allowed them to recoup an estimated $6 million dollars from that launch.
At present, SpaceX indicates that the cost of an individual Falcon 9 launch is an estimated $62 million. If the payload fairings can be recovered regularly, that means that the company stands to recoup an additional 10% of every individual Falcon 9 launch.
This news comes on the heels of SpaceX having successfully launched their Falcon Heavy rocket, which carried a Tesla Roadster with “Spaceman” into orbit. The launch was made all the more impressive due to the fact that two of the three rocket boosters used were successfully recovered. The core booster unfortunately crashed while attempted to land on one of the ASDS at sea.
At this rate, SpaceX may even start trying to recover their rocket’s second stages in the not-too-distant future. If indeed all components of a rocket are reusable, the only costs associated with individual launches will be the one-time manufacturing cost of the rocket, the cost of fuel, plus any additional maintenance post-launch.
For fans of space exploration and commercial aerospace, this is certainly exciting news! With every cost-cutting measure, the possibilities for scientific research and crewed missions increase exponentially. Imagine a future where it costs roughly the same to deploy space habitats to orbit as it does to deploy commercial satellites, and sending space-based solar arrays to orbit (and maybe even building a space elevator) is financially feasible!
It might sound a bit fantastic, but when the costs are no longer prohibitive, a lot of things become possible.
On February 6th, 2018, SpaceX successfully launched its Falcon Heavy rocket into orbit. This was a momentous occasion for the private aerospace company and represented a major breakthrough for spaceflight. Not only is the Falcon Heavy the most powerful rocket currently in service, it is also the first heavy launch vehicle that relies on reusable boosters (two of which were successfully retrieved after the launch).
Equally interesting was the rocket’s cargo, which consisted of Musk’s cherry-red Tesla Roadster with a spacesuit in the driver’s seat. According to Musk, this vehicle and its “pilot” (Starman), will eventually achieve a Hohmann Transfer Orbit with Mars and remain there for up to a billion years. However, according to a new study, there’s a small chance that the Roadster will collide with Venus or Earth instead in a few eons.
As we indicated in a previous post, Musk’s original flight plan has the potential to place the Roadster into a stable orbit around Mars… after a fashion. According to Max Fagin, an aerospace engineer from Colorado and a space camp alumni, the Roadster will get close enough to Mars to establish an orbit by October of 2018. However, this orbit would not rule out close encounters with Earth over the course of the next few million years.
For the sake of their study, Rein and his colleagues considered how such close encounters might alter the Roadster’s orbit in that time. Using data from NASA’s HORIZONS interface to determine the initial positions of all Solar planets and the Roadster, the team calculated the likelihood of future close encounters between the vehicle and the terrestrial planets, and how likely a resulting collision would be.
As they indicated, the Roadster bears some similarities to Near-Earth Asteroids (NEAs) and ejecta from the Earth-Moon system. In short, NEAs permeate the inner Solar System, regularly crossing the orbits of terrestrial planets and experiencing close encounters with them (resulting in the occasional collision). In addition, ejecta from the Earth and Moon also experience close encounters with the terrestrial planets and collide with them.
However, the Tesla Roadster is unique in two key respects: For one, it originated from Earth rather than being pulled from the Asteroid Belt into the inner Solar System by strong resonances. Second, it had a higher ejection velocity when it left Earth, which tends to result in fewer impacts. “Given the peculiar initial conditions and even stranger object, it therefore remains an interesting question to probe its dynamics and eventual fate,” they claim.
Another challenge was how the probability of an impact will change drastically over time. While the chance of a collision can be ruled out in the short run (i.e. the next few years), the Roadster’s chaotic orbit is difficult to predict over the course of subsequent close encounters. As such, the team performed a statistical calculation to see how the orbit and velocity of the Roadster would change over time. As they state in their study:
“Given that the Tesla was launched from Earth, the two objects have intersecting orbits and repeatedly undergo close encounters. The bodies reach the same orbital longitude on their synodic timescale of ~2.8 yrs.”
They began by considering how the Roadster’s orbit would evolve over the course of its next 48 orbits, which would encompass the next 1000 years. They then expanded the analysis to consider long-term evolution, which encompassed 240 orbits over the course of the next 3.5 million years. What they found was that on a million-year timescale, the orbit of the Roadster remains in a region dominated by close encounters with Earth.
However, over time, their simulations show that the Roadster will experience changes in eccentricity due to resonant and secular effects. This will result in interactions more frequent interactions between the Roadster and Venus over time, and close encounters with Mars becoming possible. Over long enough timescales, the team even anticipates that interactions with Mercury’s orbit will be possible (though unlikely).
In the end, their simulations revealed that over the course of a million years and beyond, the probability of a collision with a terrestrial planet is unlikely, but not impossible. And while the odds are slim, they favor an eventual collision with Earth. Or as they put it:
“Although there were several close encounters with Mars in our simulations, none of them resulted in a physical collision. We find that there is a ~6% chance that the Tesla will collide with Earth and a ~2.5% chance that it will collide with Venus within the next 1 Myr. The collision rate goes down slightly with time. After 3 Myr the probability of a collision with Earth is ~11%. We observed only one collision with the Sun within 3 Myr.”
Given the Musk hoped that his Roadster would remain in orbit of Mars for one billion years, and that aliens might eventually find it, the prospect of it colliding with Earth or Venus is a bit of a letdown. Why bother sending such a unique payload into space if it’s just going to come back? Still, the odds that it will be drifting through space for millions of years remains a distinct possibility.
And if there are any worries that the Roadster will pose a threat to future missions or Earth itself, consider the message Starman was looking at during his ascent into space – Don’t Panic! Assuming humanity is even alive eons from now, the far greater danger will be that such an antique will burn up in our atmosphere. After millions of years, Starman is sure to be a big celebrity!
Joe Pappalardo is the author of the new popular science and technology book, Spaceport Earth: The Reinvention of Spaceflight (The Overlook Press; Available Now). In it, Pappalardo “tackles the ever-changing, 21st-century space industry and what privately funded projects like Elon Musk’s SpaceX mean for the future of space travel.” (Foreign Policy)
Spaceport Earth takes readers on a tour of these high-stakes sites as Pappalardo examines how private companies are reshaping the way we use, intend to use, and view space travel, not solely for scientific exploration but for increasingly more general travel. Visiting every working spaceport in the United States and rocket launches around the world, Pappalardo presents a travelogue and modern history of spaceflight — where the industry is now and what’s on the horizon for explorers and consumers alike—in Spaceport Earth.