From Sky to Space
Hate your job? Canadian astronauts wanted!
Actually, it’s kind of hard to hate your job if you work in a science field. But anyway, I think you’ll like that astronaut thing as well.
If you have a science degree with at least three years of relevant professional experience (a master’s degree is equivalent to one year of professional experience, a PhD to three years) this is your chance: the Canadian Space Agency (CSA) announced on June 17 its intention to recruit two new astronauts! If you are Canadian and in excellent medical shape, please fill this online form (https://emploisfp-psjobs.cfp-psc.gc.ca/psrs-srfp/applicant/page1800?poster=908307&toggleLanguage=en) and who knows, you’ll perhaps be the next Chris Hadfield. But don’t miss out: you have until August 15!
After this the CSA will invite those who meet the basic requirements to do the online public service entrance exam (from August 23 to September 6). Those who will “pass” the exam will then be invited to be interviewed and to pass medical examinations. The CSA will then gradually restrain the number of candidates based on the interviews and medical tests results. Finally, in the summer of 2017, after one year of tests, interviews, exams and intensive physical challenges, the two new Canadian astronauts will be announced. These two lucky Canadians will be relocated to Houston, Texas, in August 2017, to begin NASA’s basic astronaut training.
Do you have chances? Let’s look at the statistics. Canada has had three astronaut recruitment campaigns. On the first one in 1983, six astronauts, including Marc Garneau, current federal Minister, were selected from more than 4,000 applicants. On the second campaign in 1992, four new Canadians were selected to be part of the astronaut corps, including Chris Hadfield and Julie Payette. That year, more than 5,000 candidates applied for the job. On the third recruitment campaign, this time in 2009, only two candidates on more than 5,000 survived the tests and finally became astronauts; they are Jeremy Hansen and David St-Jacques.
The chances are thin, indeed. They are even thinner if you consider that this time the number of applicants might be well over 5,000 because of the constantly growing communication network (notably social media). For instance, NASA’s latest astronaut recruitment campaign in December 2015 (http://espritdecorps.ca/from-sky-to-space/2016/1/13/qkditqbsl5b0wi2u15ri3xhmkib7zv) received 18,300 applications, far surpassing the previous 1978 record of 8,000!
But don’t worry. If you have the right stuff you’ll get selected, if not you won’t. But that’s OK. It will still be an incredible experience. After all, I don’t know of any other jobs with all-expenses paid voyages to space.
Gravitational waves discovered again
Remember that thing physicist discovered in September 2015, which revolutionized the whole astronomy field and solidified Einstein’s General Relativity theory? (http://espritdecorps.ca/from-sky-to-space/2016/3/23/from-sky-to-space)
Yup. Gravitational waves. Well, they’ve been discovered again!
On December 26, 2015, the Laser Interferometer Gravitational-Wave Observatory (LIGO) facility detected for a second time the sounds of space. A paper in Physical Review Letters, published on June 15, officialize the discovery (http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.116.241103).
How were these gravitational waves formed? First, you need to understand what are gravitational waves.
In a way, it’s not true that two objects attract each other; the objects bend the space around them, causing a change in their paths. What you need to understand is that empty space is something, like a fabric. Envision it like a bowling ball on a mattress, the bowling ball being a massive celestial object like the Sun or a black hole, and the mattress being the fabric of space (and time). Of course the bowling ball bends the mattress, causing any object, for instance a golf ball, to curve when it passes near the bowling ball.
Is there a special and mysterious force of attraction between the golf ball and the bowling ball? No!
The same happens when the moon orbits the Earth, or the Earth goes around the Sun, or the International Space Station revolves around us. They are like the golf ball going around the bowling ball: they follow their natural motion, or what is called in science their ‘geodesic’, because of the curved space-time.
So, empty space shares qualities with a fabric; it is able to bend, compress and dilate, giving birth to all kinds of physical events, such as gravitational waves.
So, empty space being a fabric and flexible enough to bend, it ought to be flexible enough to undulate and to vibrate, predicted Albert Einstein in 1915.
Well he was right (surprise!). When, for instance, two black holes collide, it is such a massive event that some of the energy from the collapse transforms into ripples of empty space, which we call gravitational waves.
As David St-Jacques puts it, it’s similar to people in North America asking: “Hm. Could we sense it if a cliff were to collapse on a European coast? Would the waves reach us?”
Waves obtained due to the energy liberated from the cliff collapse move through both water and air (the sound that is generated in the air by this energy occurs in the form of sound waves).
The same goes for when two black holes collide; the energy liberated from this event transforms into waves, which interact with the fabric of space, spreading beyond the point of the collision.
It’s just like the waves of a cliff collapse, but in the emptiness of space.
This time, the two black holes that merged were 1.4 billion light-years away, and each had a mass of about 14.2 and 7.5 solar masses (mass of the Sun). The final black hole (the one formed of the two that merged) had a mass of about 20.8 solar masses. As you can see, the masses don’t add up right. The missing 0.9 solar masses were converted into energy, into the form of gravitational waves! But how can one possibly measure such tiny amounts of energy spread on such huge distances? Just ask LIGO!
The LIGO facilities were arranged in such a way that two long cylinders, each measuring precisely the same length (4 km), are perpendicular to each other.
In those long tubes, two lasers are shining, being reflected at both ends and those being of the same length; it makes the lasers “come back” at exactly the same time, cancelling each other out.
The only way for the lasers to not come back at the same time is if the tubes change in length. But how can you do that? Just ask… gravitational waves!
If a gravitational wave passes through Earth, and subsequently through a LIGO facility, the tubes will change in length by a fraction of an atom(!), one being longer and the other being shorter. This way, the lasers won’t come back at the same time, and won’t cancel each other out!
It’s incredible what the human mind can accomplish, from the engineer that designed LIGO to the physicist that predicted gravitational waves.
It will open up a whole new field of astronomy!
Rocket landing gone wrong for SpaceX
On June 15, the ambitious company SpaceX, owned by Tesla Motors and PayPal CEO Elon Musk, launched its Falcon 9 rocket to deploy two communication satellites from Cape Canaveral.
As usual, after succeeding its primary mission (deploying both Eutelsat 117 West B and ABS 2A communications satellites), it tried to land the first stage of its rocket… on a ship navigating in the ocean. Up till now, nothing abnormal.
However, as the first stage of the Falcon 9 rocket came down to find its landing-target (the drone-like barge-ship), it mysteriously failed and therefore didn’t succeed in landing safely on the ship. Unfortunately, this ended a recent streak of flawless rocket landings.
https://www.youtube.com/watch?v=5H1FcVeV_II this video shows the June 15 failed rocket landing attempt as well as the three previous successful ones
So what went wrong? According to SpaceX’s CEO Elon Musk, it “looks like early liquid oxygen depletion caused engine shutdown just above the deck”. What a sad way to end a three successful landing-streak. But that’s not how Musk sees it. “As mentioned at the beginning of the year, I'm expecting ~70% success rate on landings for the year. 2016 is the year of experimentation,” he tweeted.
We still don’t have a lot of details of what went wrong that day, but we can be sure SpaceX is working on it. After all, 2016 is the year of experimentation. 4th test rocket launch and landing for Blue Origin
Surprisingly, SpaceX isn’t the only private aerospace company to perform vertical rocket landings. Blue Origin, society owned by Jeff Bezos, Amazon’s founder, also attempts the feat. In fact, it was the first company to do so! However, we need to understand the difference.
SpaceX sends its rocket into orbit, which means you need a lot of thrust and power to get there. After the first stage of the rocket sends the payload into orbit, it starts to fall, with a very high velocity, to land on a barge or on the ground. But Blue Origin’s payload/rocket doesn’t go into orbit. It sends its New Shepherd rocket out to an altitude of about 100 km (the frontier of space) and then makes it land on the ground. This is what we call a suborbital flight. Blue Origin’s version of a rocket landing is simpler than SpaceX’s, because the rocket comes down from a lower altitude, without a high lateral velocity, etc.
But it’s still a vertical rocket landing!
On June 19, New Shepherd flew again. It was the fourth flight with the booster, and the sixth flight with the capsule (designed to carry astronauts). This time, the mission was to send the capsule to about 100 km, and then land it with one of the three parachutes intentionally failing, all this while successfully landing the booster. And it worked! The capsule landed safely with only two functioning parachutes, while the booster landed vertically on the ground back in Texas, where it was launched.
Launch 0:12 rocket landing 1:50 capsule landing with one failed parachute 2:45. This is a huge step towards commercializing space, as Blue Origins intends to send tourists in space on suborbital flights and to land them and their booster on the ground safely. However, space tickets might be a little more expensive than an intrastate flight.