The Week in Space and Physics: A Shortage of Rockets
On a crunch in the rocket market, the origins of life, de-orbiting the space station and a dusty exoplanet.
Barely a week seems to go by without news of another start-up trying to put their rocket in orbit. Last week it was the turn of Relativity Space, whose Terran 1 rocket soared into the sky before falling back to Earth a few minutes later. PLD Space, a Spanish company, may be next: a launch of their Miura 1 is expected in April or May. And that’s not to mention Starship, SpaceX’s mammoth new rocket, which, as always, is said to be a month away from lift-off.
So why, with all this activity, were companies last week complaining of a crunch in the launch market? Satellite builders are, apparently, struggling to find launchers willing to take their products to orbit for a reasonable price. Of particular concern, reported SpaceNews, is the period between 2024 and 2027, when demand is far outstripping capacity.
The reasons for this crunch are twofold. On the one hand, demand is soaring. SpaceX is putting up thousands of satellites, a project that consumes dozens of launches a year. Amazon has purchased over eighty launches to put up their planned Kuiper constellation. Other companies, eager for a piece of the action, are purchasing launches as fast as they can.
Supply, however, has failed to keep up. Despite an array of startups and a lot of hype, few companies have actually managed to get their rockets to orbit. SpaceX and Rocket Lab remain the biggest players, with SpaceX targeting one hundred launches this year alone. While many of the new entrants may eventually succeed, it will probably take them years to ramp up production and capabilities to launch as much as is needed.
The problem seems even worse in Europe. For years the continent had relied on Russia’s Soyuz rockets to meet a portion of its demand. The war in Ukraine has made that option politically infeasible - and as a result, several big European projects are now stuck without launchers. Arianespace, Europe’s rocket behemoth, is unable to help: the first launch of its flagship Ariane 6 rocket has been hit by delays, and its smaller Vega C rocket suffered an embarrassing launch failure earlier this year.
How long this crunch will last is unclear. High demand seems likely to last for a while - at least half a dozen satellite mega-constellations are planned. Yet the abundance of rocketry start-ups currently trying to reach orbit means more rockets will surely become available before long. Existing companies like SpaceX could also do more to meet demand - especially if Starship proves a success.
Indeed, so many rockets are currently in development that some fear overcapacity rather than undercapacity will soon be the problem. Should all these companies succeed - still an open question - then launch prices are likely to tumble.
That possibility may already be weighing on investors’ minds. Virgin Orbit, a California based company, was forced to suspend operations earlier this month after funds ran short. Rocket Factory Augsburg, a European start-up, likewise suffered the recent loss of a major backer. Getting off the ground, in years to come, may prove the easiest part of running a rocket company.
Life from the Stars?
How did life begin on Earth? Though researchers have traced back the tree of life over billions of years, the question of how life began - how chemistry became biology - has remained one of the deepest mysteries of science.
Most life is based around the chemical DNA, but scientists suspect that primitive lifeforms may have used an alternative molecule, RNA. Like DNA, RNA can store information and replicate itself. It can also help other chemical reactions take place - especially those that drive life.
Crucially, RNA is a far simpler molecule than DNA. Some evidence, indeed, hints that RNA molecules can spontaneously form if the right ingredients are present. Triggering the formation of life likely takes a few more steps, but getting that process going may be as simple as gathering the right ingredients in the right place.
In recent years, evidence has emerged that these ingredients form naturally in outer space. Studies of asteroids found in Antarctica have revealed the presence of molecules that can come together to form DNA or RNA. Others have found signatures of these molecules around young stars, on the surface of Saturn’s moon Titan, and even in the centre of the galaxy.
Yet none of these observations has provided direct proof that these molecules really exist in space. Asteroids, for example, can be contaminated after reaching Earth. Researchers could have been fooled into thinking chemicals that actually originated on Earth somehow formed in the lifeless depths of space.
Fortunately we are now beginning to recover pristine samples directly from comets and asteroids. At the end of 2019, Japan’s Hayabusa2 probe visited the asteroid Ryugu. While there it collected several rock samples from the asteroid’s surface. These were later sent back to Earth, where scientists were waiting to retrieve them. A second mission, by the American OSIRIS-REx probe, collected another sample from the asteroid Bennu. That sample should come back to Earth later this year.
Analysis of the samples from Ryugu, published in Nature last week, found traces of uracil - a key ingredient in RNA - as well as of other molecules, including Vitamin B, that play an important role in life on Earth. The findings suggest that these chemicals are widespread across the Solar System. Indeed, they were likely present billions of years ago, when the Earth and other planets came into being. Could asteroids like Ryugu have delivered the key ingredients for life to Earth?
Whatever the truth of that, the discovery does raise the likelihood that these chemicals are widespread across the cosmos. And, since life apparently got started early on our own planet, it seems likely that it must have done so elsewhere. But if life really is widespread, then where is it?
NASA Prepares for the End of the Space Station
Later this year the International Space Station will reach its twenty-fifth birthday. For twenty-two of those years it has hosted crews of astronauts, making it the longest continuously inhabited place in orbit. Yet at some point - perhaps within the next decade - the station will be shut down, its astronauts will depart and NASA will begin the careful work of deorbiting it.
That promises to be a challenging undertaking. The station is by far the largest thing ever built in orbit - it weighs over four hundred tonnes. Big chunks of it are thus likely to survive plunging through the atmosphere. NASA, therefore, proposes to direct the station towards a remote area of the Pacific Ocean, where the risk to human life is minimal.
In a sign that planning for this demise is becoming more serious, NASA recently requested the first funds towards building capabilities for a controlled re-entry. NASA’s budget request for 2024 includes $180 million for the development of a deorbit system. This is likely to take the form of a dedicated tug that will carefully bring the station down.
Details about this tug are still vague. NASA last year started talking to industrial partners about the form this spacecraft could take. Now they suggest that its overall cost could come close to one billion dollars. Not everyone, however, is happy about the idea. Some suggest that NASA should instead hand the station over to commercial partners in the 2030s, allowing them to repurpose and recycle its components.
The James Webb Spies a Dusty World
The power of the James Webb continues to amaze. Astronomers reported last week on observations of a large exoplanet sitting roughly forty light years from Earth. Within its atmosphere, they say, are swirling clouds of dust rising and falling over periods of hours.
The planet, VHS 1256b, is huge, roughly twenty times bigger than Jupiter. It is also hot, with temperatures in its upper atmosphere reaching over eight hundred degrees centigrade. That upper atmosphere seems to be turbulent, with clouds of sand and dust spotted by the James Webb. Over the course of the planet’s day, those clouds rise and fall, creating a steady variation in the planet’s brightness.
The telescope also picked out signs of water, methane and carbon monoxide moving through the atmosphere. Such traces have been found on other worlds, of course, but the observations of VHS 1256b represent some of the clearest ever taken of a world beyond our Solar System.