All posts by Debjyoti Bardhan

Is a science geek, currently pursuing some sort of a degree (called a PhD) in Physics at TIFR, Mumbai. An enthusiastic but useless amateur photographer, his most favourite activity is simply lazing around. He is interested in all things interesting and scientific.

Now, Chinese Scientists Want To Capture An Asteroid Into An Orbit Around Earth

The world is truly not enough anymore. Chinese astronomers want to capture a near earth object (NEO) and force it to orbit Earth. What about the risks, you ask? What about the rewards, comes the answer!

The Asteroid intended for capture. From the arXiv paper of the Chinese astronomer team.

Petting an Asteroid

Researchers from Tsinghua University in Beijing want to emulate artificially what Jupiter does on a regular basis capture asteroids. Here’s the trick: Planets will pull smaller objects into an orbit around themselves if the object passes close to them. Now, if the planet is large enough, the orbit will be closed around the planet. Otherwise, the body can just complete a turnaround and fly off into space again. Most of the time this is what happens for Earth. There are many asteroids which get deflected from their paths due to the Earth’s gravity. The Chinese astronomers argue that if we can nudge it just a bit and in the right direction, we can bring it into orbit around the Earth.

The trick Jupiter does to often!

So, what of the obvious dangers? What protection do we have if we make a mistake and find an asteroid hurtling into the sea? Simple the atmosphere. The NEO that the scientists want to study is called 2008EA9, which is a mere 10 meters across and is due to pass Earth in 2049. The group even has a paper published in one of the Chinese Astrophysical Journals.

Why an asteroid? We can look at the asteroid for a few years continuously. We can mine for minerals on the asteroid. We can impinge them and get to know how the Solar System came to be. And then, we can send them on their way out into oblivion once again.

So wait for a few years you might be able to keep an asteroid.

Discovered: Two Nearby Supermassive Black Holes Gobbling Up Each Other

This is cannibalism on the cosmic scale. Two black holes have been found by the Chandra X-Ray Telescope gobbling matter from one another. The black holes are in the process of merging with one another. The real excitement is that this is close to home on the scale of the cosmos about 160 million light years away.

The Giants!

The galaxy in the limelight is NGC3393. The two black holes are separated by only 490 light years. One of them has a mass of 30 million suns and other is much smaller at one million solar mass. The bigger one is gobbling up matter surrounding the smaller one.

Chandra's Picture of the twin black holes. (Photo Courtesy: NASA/CXC/SAO/G.Fabbiano et al; Optical: NASA/STScI)

The close proximity of the black holes has also got scientists excited. It is because these supermassive black holes are so close that Chandra could resolve them into two distinct objects. When a black hole accretes matter, i.e. just gathers by sucking the matter around it, the matter gets hot enough to radiate profusely in the X-Ray region. These radiations occur close to the event horizon and this is where Chandra X-Ray Telescope can work its magic. But even Chandra couldn’t have spotted such a double black hole system if it were farther away.

Many that got away?

What we are seeing is really a merger. Black holes merge to become even bigger black holes. It is surprising that NGC3393 still retains the elliptic shape that it originally had. The perturbations occur near the central part and do not propagate throughout the galaxy. NASA scientists think that this is one reason why black hole mergers or double black hole systems have rarely been observed till date. The expected tell-tale signs like galactic perturbations are not really there. Astronomers now want to train Chandra’s eagle-eye on more boring candidates.

The findings were published yesterday in the science journal Nature.

The Universe is not only queerer than we imagine. It is, by all means, queerer than we can possibly imagine!

Hurricane Irene Blows In Baby Boom On The East Coast

It was a strange coincidence and a happy one for many! While Hurricane Irene brought in a frantic scurry for many and really bad news for a few people, it also supposedly brought smiles to a number of mothers, who just delivered their bundle of joy. There was a baby boom in some hospitals on the East coast during the torrid weekend reconfirming people’s belief that a drop in the atmospheric pressure helps bring in labour quicker in pregnant women.

Joy Unbounded!

We would hurry to say that this belief is unfounded and is not scientific. There have been studies aimed at linking early labour with drop in the barometric pressure, but all have been inconclusive. There is just not enough correlation to prove the hypothesis. The rumour still persists.

The Boom

At the Sentara Obici hospital in Suffolk, Virginia, there were a record 15 childbirths that took place between Friday night and Sunday morning in the space of 30 hours or so. This is way greater than the usual rate of three or four a day. Further, New Hanover Regional Medical Center in North Carolina reported a staggering 17 babies during 18 hours from Friday night onto Saturday evening. This hospital sees about 11 to 12 babies a day.

When it came to names, however, Irene didn’t seem to find too much of popularity amongst the parents. Only two girls born at Pitt County Memorial Hospital in Greenville, North Carolina were named Irene’. But this was the wrong place to go, if you wanted to see a baby boom. Pitt County reported a lesser than average number of babied being born.

Here’s wishing all the new mothers and their bundles of joy the very best.

Cause Of Black Death Established from Genome Sequencing: It Was The Bubonic Plague

The Black Death bacteria may be gone forever! Scientists have identified the cause of the infamous Black Death bacteria with almost 100% confidence. While it was widely believed that the Black Death was caused by the plague bacteria both inside and outside the medical community, it wasn’t an established fact. Now it is, thanks to modern genetics!

Black Death

The Black Death wiped out an estimated one-third of Europe during the 14th century. Fields turned into mass graves and it was suggested that not one household was spared some effect of the Black Death or the other.

The Dreaded Bacterium

The Black Death was caused by the bacterium Yersinia pestis, one which is responsible for current plague outbreaks, said Hendrik Poinar, an anthropologist at McMaster University in Ontario. No one can doubt now that bubonic plague was the cause of the horrible epidemic.

The Y.Pestis bacterium

It was Hendrik Poinar who did pioneering work in developing a technique for extracting the DNA from the bones of the Black Death victims and then analysing the genome structure. He got definitive signatures of the Y.pestis bacteria. Samples from death bodies before the Black Death did not contain any strain of Y.pestis, while those of the victims did. This deadly Y.pestis strain, however, no longer exists and Y.pestis has mutated into a less harmful form. It still causes bubonic plague outbreaks, but these are nowhere as deadly as the medieval European version. In other words, Black Death bacterium is extinct.

Some scientists had suggested a strain of the Ebola virus, but this settles the issue. Ebola DNA was not found in the bones.

This is a fascinating story of modern genetics reconstructing history and also giving valuable lessons on disease control in the future.

Juno, the Jupiter Satellite, Looks Back And Snaps A Photo Of The Earth-Moon System

It is the Pale Blue Dot redux. Juno, the Jupiter satellite, looked back at the Earth Moon system and snapped a photo! Here it is!

The photo Juno snapped of the Earth-Moon system. The larger dot is the Earth. (Courtesy: NASA/JPL-Caltech)

Juno was sent to Jupiter to probe the composition of Jupiter’s atmosphere, which is still a big mystery. It’s been a month into its journey, which is supposed to last for five long years.

NASA has pinned a lot of hopes on this satellite probe. Jupiter is still largely unknown. We covered the Juno story here.

The Pale Blue Dot

The lyrical prose by the late Carl Sagan rushes back to haunt us! In 1991, at Sagan’s request, Voyager turned its camera back to photograph the inner planets. It was beyond Neptune’s orbit and was about to leave the Solar System. It captured one blue pixel, which was the earth. The picture was immortalised as the Pale Blue Dot’. The following paragraph by Carl Sagan is as close prose can come to poetry.

From this distant vantage point, the Earth might not seem of any particular interest. But for us, it’s different. 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.

Sagan taught us how to look at these photos. It’s an exercise in humility!

Image Credit: NASA/JPL-Caltech

Milky Way Galaxy Simulated For The First Time After Nine Months on Supercomputers

It took nine months to reproduce our galaxy, but it was well worth the effort! Researchers at the University of California, Santa Cruz and the Institute for Theoretical Physics in Zurich created this stunning reconstruction of the Milky Way galaxy by running a simulation on a supercomputer for nine long months. The result is not only beautiful, but also significant in scientific terms. And just for the records, this is the first time such a simulation has been achieved!

The Eris Simulation (Courtesy: UC Santa Barbara)

 

There have been many previous attempts. Every one of them resulted in failure, usually ending up with a huge central bulge. Javiera Guedes, the first author of the paper on the simulation, says it better:

Previous efforts to form a massive disk galaxy like the Milky Way had failed, because the simulated galaxies ended up with huge central bulges compared to the size of the disk

The paper has ben submitted to the Astrophysical Journal and has been accepted for publication. The simulation is remarkably close to the Milky Way. The authors call their simulation Eris’. Take a look as to how close it is to the actual thing in the picture below:

Comparison between the Eris simulation and the Milky Way Galaxy

Cold Dark Matter

The model simulation is important for the support it lends to the ‘cold dark mattertheory of cosmology. Dark matter is a hypothesis used to explain the rotation of galaxies amongst many other things like Cosmic Microwave Background Radiation. The amount of matter we see in the galaxy cannot provide enough gravitation to hold the spinning galaxy together, so scientists postulated the presence of another type of matter one which does not interact with other matter at all, but provides the necessary gravitational pull. Since, it doesn’t interact and cannot be seen’, it is called Dark Matter. There are many models for Dark Matter too. One of them involves particles moving at low speeds, or are cold’.

The key to the success of this team, where many previous attempts have failed, has been the correct simulation of the star formation process in real galaxies. Star formation happens in gas clouds in clumps in the galactic region. These pockets are supported by Dark Matter. Dark Matter halos create gravitational wells, or regions where the gravitational potential is low. These are the regions that matter can reside in and are the hotbeds of gas clouds.

What took nine months?

The remarkable success of the team was the amazing resolution they could achieve. Resolution means tracking several stars and simulating their interactions with each other, both extremely tough jobs. NASA’s Pleiades supercomputer and other supercomputers at UC Santa Barbara and the Swiss National Supercomputing Centre came to the rescue, but together they took nine months to process the data.

Simulations are always satisfying since they assure us that what we know is not wrong. This one is a strong case in point.

International Space Station May Need To Go Unmanned For First Time In A Decade

The International Space Station (ISS) may go unmanned in the coming months for the first time in a decade. This is because of the crash of the Russian space vehicle last week. The vehicle was supposed to carry essential supplies to the International Space Station and the astronauts on it.

While there is no dearth of supplies presently, the Russian space agency, Roskosmos, has decided to delay the launch of the next rocket to the ISS. This does put a constraint on the supplies and the astronauts may be asked to descend to earth in November, deserting the ISS. The ISS will then be controlled from the ground via remote control.

Anybody Home? (The ISS)

Of Delays and Remote Controls

Though this is not new, it is a drastic measure. The last time the ISS was unmanned was in 2001. The procedure is present in NASA’s books, but it is a difficult procedure nonetheless. The ISS can be far effectively monitored on-board than from the ground.

Roskosmos gave a sound reason for their decision to delay this present launch, however. They want to check everything thoroughly, so as to prevent a rerun of last week’s embarrassing disaster. Many have started saying that, if the Space Shuttle were in operation, this kind of crisis would never have arisen. Right now, Russian rockets are the only way to get in or out of the Space Station and they are showing glitches. The Soyuz is, however, on standby at the ISS should an emergency arise.

The present crew of three astronauts was supposed to head back to earth on the 8th of September, but even that has been pushed back to 16th. A fresh batch was set to replace them on the 22nd of September, but this launch has been pushed back to early October. Roskosmos and NASA are now thinking whether this launch will be scheduled at all or not.

Meanwhile, the $100 billion floating behemoth silently endures.

Why Hurricane Irene Fizzled Out After Initial Scare

When they got it wrong, they got it spectacularly wrong! Meteorologists have become the newest subject of many jokes in recent days, as they got the storm prediction of Irene embarrassingly wrong. Hurricane Irene was nowhere near as big as it was made out to be! What was supposed to be a major storm and cause widespread mayhem, fizzled out to become a bit more than a strong breeze. Yes, it did rain and yes, trees were uprooted in many places, but the weather guys had warned us about far worse things. We would like to stand behind the weather forecasters and explain why the predictions were so far off-the-mark.

Flooding in New York City

Irene’s Energy Sink

The greatest sink of Irene’s energy was the cold water it was moving into. As storms move northwards, the ocean temperature drops and the energy reduces. This effect is marked if there are no other sources of energy like warm water currents. The cold waters east of Delaware and Maryland did the trick. Further, any storm weakens as it encounters terrain, as it cannot pick up energy as it could from over the water surface. What was really surprising in Irene’s case was the rapidity with which the storm downgraded itself from a fearsome Category 3 storm with wind speed of 115 mph to a Tropical Storm barely registering 60 mph.

The Collapse that saved many others

The US Meteorological Department provides the answer. There was a wall of moisture laden clouds spinning at over 100 mph near the eye of the Hurricane. This inner eyewall’ was supposed to collapse and be replaced by an outer eyewall’, which would then shrink and replace the inner eyewall. While the collapse of the inner eyewall would represent a decrease in storm intensity, the replacement procedure has been associated with the strengthening of the storm. In case of Irene, the outer eyewall never materialized and when the inner eyewall fell, the storm weakened rapidly. The energy, which was supposed to be concentrated over a small area, spread out. The rain bands disassembled themselves and the result was a Tropical Storm.

Another factor was the wind system over the Great Lake region, which spread eastwards and sapped away energy from the Hurricane, through a process called wind-shear’.

Be Fair!

To be fair to meteorologists, this kind of process involves so many parameters that it is impossible to be spot-on every time. Being on high alert and then relaxing is better than being caught off-guard.

An uprooted tree in New York City: Not Enough Huh?

Irene was not completely harmless. It did kill 16 people, uprooted several trees and flooded Lower Manhattan and New York. It is indeed fortunate that nothing worse happened.

Futuristic Look for Nuclear Power Plants Set to Power Colonies on Moon and Mars

Nuclear energy is the answer to the energy question of deep space travel. It is also the answer to setting up large working domes on Mars and Moon, similar to what sci-fi writers have led us to believe throughout the years. Unfortunately for them, they got the design of the nuclear power plants wrong. The new power plants are expected to be extremely futuristic, not in the least bit like what we see on Earth.

 
This is what nuclear power plant cores might look like in future, as we set foot on Moon and Mars. (Courtesy: Galaxy Wire)

The Design

A team is working on this design and a leader of the project, Dr. James E. Werner, laid down the plans at the 242nd National Meeting and Exposition of the American Chemical Society (ACS). In his own words:

The reactor itself may be about 1 1/2 feet wide by 2 1/2 feet high, about the size of a carry-on suitcase. There are no cooling towers. A fission power system is a compact, reliable, safe system that may be critical to the establishment of outposts or habitats on other  planets.

Nuclear power has a lot of advantages over the conventionally used sources of power like Solar cells and fuel cells. The main advantage is that nuclear power can be produced and used anywhere. The generation of nuclear power doesn’t require special conditions, unlike solar power. The source of power is the Uranium nucleus, which splits into lighter nuclei releasing energy in the process.

A Demo

The demonstration of this innovative technology is expected as soon as early 2012. The project is a collaborative effort between NASA and the US Department of Energy (DOE). The benefit to both organisations is easy to guess. Dr. Werner is associated with the Idaho National Laboratory, under the DOE.

This may indeed power the future, which will definitely see humans colonising either the Moon or Mars.

Discovered: A Huge River That Flows Underneath The Amazon!

This has got to be amongst the weirdest things you’ve heard! Get this: there is actually a river flowing beneath the mighty Amazon!

Scientists have discovered evidence of an underground river, complete with a river basin and features like valleys, flowing 13,000 ft underneath the Amazon. The Brazilian National Observatory, credited with this discovery, has named the river Hamza, after the scientist Valiya Hamza, who has been studying the Amazon for 40 years.

The mouth of the Amazon

A new river – a new type of river!

The Hamza is pretty impressive on its own right, even though it is dwarfed by the Amazon. It is 3,700 miles long, with the Amazon being 4,200 miles long. The Hamza flows along the same slope as the Amazon i.e. from west to east, but at a much slower speed than the Amazon owing to much smoother height gradient underneath the surface.

The river has almost been confirmed, but Hamza is willing to wait till 2014 to get the absolute final confirmation before saying hurrah. The data is primarily obtained from 240 wells drilled into the Amazon region in the 1970’s and 80’s. The wells go down to depths of upto 4,000 meters.

The features of the underground river may be pretty impressive. Scans show that there are vertical drops at 2000 feet depth, but it the river becomes sluggish soon after at greater depths, owing to flat topographical features.

Here’s a video explaining the river in brief.

The effects of this river might have already been apparent for a long time. The salinity levels at the mouth of the Amazon are unexpectedly low and the Brazilian National Observatory claims that the water from the Hamza might be responsible for the unexplained dilution.