From Space X to Starshot, Plus Some Sobering Earth Day News

There have been two exciting bits of news in the field of space exploration in the last few weeks, though one of them is considerably more immediate than the other. The first is that after several attempts that narrowly failed, Space X finally managed to land one of its rockets on a floating barge at sea. This is only the second time a rocket used to launch objects into orbit has landed again successfully and the first time anyone has landed a rocket at sea. A few months ago, Space X landed a rocket on land, and its rival Blue Origins has landed and reused a rocket, though theirs was a suborbital one. While landing a suborbital rocket is a significant achievement, it is still easier than landing one that has been used to boost an object into orbit, as the latter return to Earth at a much higher speed. And naturally landing a rocket on land is easier than landing one on a moving platform at sea. But as Space X founder Elon Musk and others have explained, if these rockets are to be fully reusable, it will often be necessary to land at sea, as returning to the original launch site to land requires more fuel than may be left in the rocket, depending on the circumstances of the launch.

So why is this a big deal? A rocket costs tens of millions of US dollars or more, and yet up till now, every rocket that has been launched has been a one-shot deal. If Space X is able to regularly reuse rockets, that will reduce the costs of launching objects into space dramatically. This will lead to space becoming more widely accessible, and will open up all sorts of possibilities. Of course, one success doesn’t mean that Space X will manage to land and reuse all of their rockets in the future, but even if they do so with a significant percentage, that will make a big difference. Maybe within as little as a decade, advances by companies like Space X will lead to a huge increased human presence in space. Besides that, watching a rocket land on a barge is cool, all the more so when the barge is named for one of the humorously and idiosyncratically named intelligent spaceships from Iain M. Banks’s Culture novels, in this case “Just Read the Instructions” (Space X’s other barge is named “Of Course I Still Love You”).

The other exciting piece of space news is admittedly much less likely to lead to any actual results in the near future, but if it does come to fruition, it could potentially be as exciting as a human mission to Mars. This is a project announced by Nobel laureate Steven Hawking and Russian billionaire space enthusiast and physicist Yuri Milner called Breakthrough Starshot. They propose to develop and launch a fleet of miniature spacecraft equipped with light sails, and to use a giant laser array to accelerate them to a significant fraction of the speed of light (as much as 0.2c, or 20% of light speed) in the direction of Alpha Centauri, the star system nearest to the Sun. The spacecraft will be tiny – a mere centimeter or so in size – which is what will make it possible to accelerate them to such a high speed. The basic technology for the project already exists, but it will still need considerable refinement and improvement, and there are numerous engineering obstacles to overcome, from construction of the laser array to avoiding overheating the spacecraft to aiming the spacecraft. It will probably take several decades before anything is actually launched, even assuming the difficulties can be overcome.

If Hawking, Milner and their cohorts succeed, however, it could be a transformative moment for humanity. As I have discussed before, even Alpha Centauri is incredibly far away. A spacecraft like New Horizons, which recently flew by Pluto after a nine year journey from Earth, would take many tens of thousands of years to reach Alpha Centauri. The Starshot miniature spacecraft would get there a thousand times faster, perhaps arriving as soon as half a century from now. While such tiny ships would be limited in what they could do, they should at least be able to take a few pictures and gather basic data. If there are planets orbiting either of the main components of the Alpha Centauri system, that would be incredibly exciting. Even if the only planets present are uninhabitable ones, it would be extremely dramatic to get our first relatively close up pictures of an alien world outside our solar system. But if there is an Earth-like planet in the habitable zone of either star, pictures of it would almost certainly inspire an all-out effort towards further interstellar exploration, perhaps even eventually by humans – though without some unforeseeable breakthrough, that will take centuries, even with the knowledge of a potentially habitable (or even inhabited!) planet a few light years away to motivate us.

But we will certainly not be able to launch any large scale interstellar missions in the coming centuries or even take advantage of cheaper space travel to colonize the Moon or Mars in the coming decades if our civilization can’t survive climate change. As it’s Earth Day, I’ll close with a much more sobering piece of news. Not only was this past March the warmest March on record, making it 11 months in a row that a new monthly record has been set, it surpassed the average by more than any month ever. While even past record setting months have seen a few parts of the globe where temperatures were noticeably cooler than average, it was warmer than average nearly everywhere last month, and in many places regional temperatures also set an all-time record for the month. While part of this is because of El Nino, this past year has been far warmer than 1998, the last year with a strong El Nino, and the first three months of 2016 have been easily the warmest three month period ever. If this keeps up, 2016 could beat 2015 as the hottest year ever, just as 2015 beat out 2014. Even with the end of El Nino, global temperatures are unlikely to drop back to the levels of even the 1990s any time soon. Since even if humans do manage to colonize space in the near future the Earth will remain the home of the vast majority of humanity, we really have to get cracking if we want to keep it livable in future centuries.