Where is everybody?

Aliens, NASA, Space, Uncategorized, Vintage space

For most of us, the idea of finding an extraterrestrial life form is a grand notion, the inspirations of which are driven more often by science fiction than by science. So, rarely do we write a fascinating story about finding an alien microbe on a distant planet or of a cute alien bug paying us a visit. We want our first encounter with an otherworldly life form to be an extraordinary story, hopefully, one including a savvy spaceship and a very mysterious but friendly creature inside. We want them to have skills that we do not possess, we want them to be intelligent and above all we want them to really really like us.

When you work in a similar field this is a question you are asked very often and it almost always throws me off- mostly because my understanding of it is still based on anecdotal references and little on facts. So this article is also a way of me trying to get a sense of how to hold a realistic discussion about life outside earth. It is funny, as soon as you start to see what science has to say on this, a lot of the mystery starts wearing off as you start running into studies and theories that are contradicting each other, statistical charts that do not give you an intuitive understanding of the issue and uncertainties on the authenticity of sources.

alienbug

i didn’t mean him to look like a banana

Starting with the question of odds, Fermi paradox in simple terms describes the contradiction that seems to exist between the high probability that an intelligent life form can exist somewhere in the universe and the extreme lack of evidence of the same. There is a story of Enrico Fermi yelling out in frustration during lunch hour “Where are they?” which could be understood as a layman’s version of that paradox. So what is that high probability Fermi was talking about? Based on the Kepler space mission data there are about 11 billion Earth-like planets orbiting a sun-like star in its habitable zone in the milky way galaxy alone- the nearest of which is located about 12 light years away [source: NASA JPL]. Even simply assuming only earth like planets can hold life that is already a staggering number.

Now, how do we or what do we look for to detect life? The space missions focusing on extraterrestrial lives, look directly for biosignatures that might prove that life has existed outside of earth in some form. We currently have rovers on the surface of Mars that are capable of looking for/recording them. Another direct way of inquiring for life would be looking for the presence of life-sustaining features (as we understand it) such as the presence of water/methane/atmosphere. Jupiter’s moon Europa and Saturn’s moon Titan have been very interesting candidates in this regard for several years now owing to the strong possibility of a liquid water ocean beneath its icy surface and the presence of a significant atmosphere respectively.

Now on to the big question of why has no-one contacted us yet? To answer that I am linking an equation here which you will come to see is only intimidating in its length.

{\displaystyle N=R_{*}\cdot f_{\mathrm {p} }\cdot n_{\mathrm {e} }\cdot f_{\mathrm {l} }\cdot f_{\mathrm {i} }\cdot f_{\mathrm {c} }\cdot L}

This is the Drake equation which is more a mathematical formulation of probabilities than a definitive tool, gives the number (N) of Milky Way galaxy civilizations already capable of communicating across interplanetary space. The only thing we need to understand here is the term L which is the length of time over which such civilizations broadcast detectable signals into space. So intuitively this would mean if an alien civilization is not capable of developing a technique to reach out in a detectable way, we might never get to know them. Although the validity of this equation has been widely contested it still gives us a vague answer of why no one might not have contacted us yet.

The Voyager probe carries a Golden record on board that contains a cornucopia of information on us humans. Even there, our understanding of an intelligent species is of one similar to life on earth, ones who are capable of having technologies that could decode recorded pieces of sound.

Image result for golden record

“The chances of aliens finding the Voyagers in the vast emptiness of space are small — some say infinitesimal — but we took our jobs seriously,”

 

The Golden Records were carefully designed to reach extraterrestrials, and now they’re within reach of the public.

Arrival is one of my favorite movies on this subject. It at least began to question our cliched understandings on this subject.

This post really fails to accomplish what I set out to do but at least I hope it has given you some starting points to go out and explore discussions on alien life that are shy of UFO sightings and crop circles.

See you soon with another snippet of this fascinating universe that we live in.

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Yes, there is a lot of junk in space

NASA, Space, space debris

Space Debris is still a relatively unknown term. I realized that when a friend of mine who works at the University of Southampton tried introducing himself as a Space Janitor at a family function- let’s just say that the joke didn’t land anywhere in this galaxy. Space Debris in the context of our discussion are all man-made objects that are still in orbit around the earth which no longer serves a useful function. There are around 500000 pieces of space debris larger than the size of a marble currently orbit the earth, out of which around 20000 objects are larger than 10cms -that is about the size of a softball.

For those of us who are surprised at this staggering number, let’s get some perspective- since Sputnik-1 was launched on Oct 4, 1957, humanity has collectively placed/ launched a grand total of about 7500 satellites into earth’s orbit, out of which only 1200 are still functioning. Add to that, abandoned rocket stages, mission-related debris and other fragmented debris and there we have that seemingly large number. If the list seems a bit boring, there is also Gemini astronaut Ed White’s glove and NASA astronaut Sunita William’s camera floating around somewhere.

A lot of these particles are of a minuscule size, but they travel at a velocity of around 28000kmph and to get an idea of the sort of damage these orbiting space debris particles can cause, here is a photograph from the Cupola of the International Space Station. We can see a visible break in the glass window, it was created by a possible paint fleck/ tiny speck of metal.  The crew module of the ISS is actively protected against collisions but most of the earth returning astronauts have stories of replacing a cupola window glass to share.

 

Image result for iss space debris

Fig 1: courtsey astronaut Tim Peake

 

A large portion of  spent spacecrafts re-enter the earth’s atmosphere owing to the drag force of upper atmosphere where orbital energy is converted into heat which is sufficient to destroy smaller size objects, although approximately 20–40% of the mass of larger-size spacecrafts or rocket bodies, or parts made of particularly high-melting steel or titanium alloys may survive the re-entry. Space novelties making its way back to earth have given way to several interesting speculations, consider this story for instance, the Merkanooka ball, a small Titanium sphere spotted in Western Australia in late 1960’s which was speculated to be connected to a UFO phenomenon turned out to be a tank used by Gemini V astronauts for drinking water.

In fig 2, we can notice two clear spikes in the space debris distribution over the years. Two separate events have contributed to the overall space debris distribution. The first peak in the graph titled Iridium-Cosmos breakup happened on 10th of February 2009- Cosmos 2251, an inactive Russian satellite collided with the US-based Iridium Satellite LLC. This collision produced around 2000 pieces of debris measuring at least 10cms and many thousands more of smaller pieces.

While that collision of satellites was an accident the Fengyun- 1C breakup was an intentional destruction. In January 2007 an anti-satellite device launched by China collided with the Chinese weather satellite Fengyun- 1C that resulted in about 900 pieces of catalogued debris particles around the Earth. The satellite’s destruction is now being viewed as the most prolific and severe fragmentation during five decades of space operations.

Image result for space debris distribution over years

Fig:2 Source NASA

 

A variety of strategies have been proposed by agencies worldwide for harpooning, sweeping, lassoing and dragging debris into the atmosphere for burning or pulling it  into a so-called graveyard orbit, where they can’t collide with an operational equipment. Although very little has been done in terms of testing or verification, some of these ideas are perfect examples of the sort of magic that happen only when several seemingly different fields of study come together with a common objective.

So, what are some of the wildest ideas of Project Space clean up? Let’s look:

Laser broom

The idea here is very promising and straightforward. A high power pulsed laser system is used to make plasma jets on objects, slowing them down and causing them to re-enter and burn up in the atmosphere. The challenges with this plan are more political than technical.  The Outer Space Treaty prohibits any attempts of placing weapons of mass destruction in the orbit around the Earth. Although a laser cannon might not seem like a weapon of mass destruction, the idea of having an instrument in Space that could potentially bring down a functioning Satellite might need more than a little bit of political correction factor to come to fruition.

SpaDE

Raytheon BBN Technologies (BBN) and the University of Michigan will study the Space Debris Elimination (SpaDE) system to remove debris from orbit by firing focused pulses of atmospheric gases into the path of targeted debris. These pulses will increase drag sufficiently to cause the deorbit rate to exceed the debris generation rate. The pulses themselves will fall back into the atmosphere, leaving no residual trace in orbit to interfere with LEO satellites. In contrast to other proposed methods, SpaDE is failsafe, in that it places no solid material in orbit where a malfunction could create new debris. [NASA]

Space Net

This might be the most intuitive of all the ideas and my favorite one of all. If the idea of wielding a net into a vast expanse is conjuring up an image of a lonely fisherman and an endless ocean, you are not alone. A 106-year-old Japanese fishing net making company, Nitto Seima Co. is teaming up with JAXA, the national space agency of Japan in making metallic line nets that could tether and drag space junk into lower atmosphere where it can burn up.

Image result for space net space debris

Image courtsey- ESA

As we can see from this coles notes version of Project-Space-Clean-Up a majority of these methods are still in the very early stages of execution. The burning question at the end of this discussion is are we under immediate threat. The answer is Yes and No. Provided no unexpected big collisions happen in Space, certain estimates give us about twenty years of time, which might seem like a lot. But the usual timeline of even routine space missions can drag up to 3 to 4 years and with the potential of threat that even minuscule paint particles can cause to spacecraft, this might already be late to be proactive and join forces to keep outer space clear for further exploration.

that pale blue dot

NASA, Space, Uncategorized, Vintage space

I remember someone somewhere saying that they would prefer to live in the space between the right and left cerebral hemispheres, no, it wasn’t me. We are not in the era of renaissance men anymore, but the divide we have between science and art these days is appalling.

Image result for pale blue dot image

We have all seen his picture. We know the profound sense of insignificance of our worldly problems that come with this view. But we have this image because we had an incredible human soul, Carl Sagan. He asked to turn the Voyager around to take a one last look. Here is the deal, we did not need this picture, there are no quantitative scales that can return tangible values of what this image has done to humanity. But does that mean it is worthless?

Money spent on exploratory missions is considered a luxury, an afterthought, a thing we could do without, a thing we do not need. Yes, we have problems that are real, tangible and here. The money spent on an interplanatory mission could be redirected to feed and house those in much dire need. But, can we in all honesty say that we have poverty on this planet because we go to space? No-one has to think twice to answer with a resounding No.

When savings that we make from advancements in technology is not going back to the society we have a problem, when richest 1% of the world owns half the world’s wealth that is a problem. When it is almost impossible to go on own living a life without buying something from Jeff Besos, that right there is a problem.

We as humanity have it in us to solve more than one problem at a time.

Look again at that dot. That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every “superstar,” every “supreme leader,” every saint and sinner in the history of our species lived there–on a mote of dust suspended in a sunbeam.

The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds.

Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.

The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand.

It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we’ve ever known.

— Carl Sagan, Pale Blue Dot, 1994