A Tribute To Dharam Dev Anand

Image of Dev Anand

Entitled Bollywood’s Peter Pan, Dev Anand was the quintessential yet the most inimitable actors of the Indian film industry. Revered and fondly known as Dev Sahab the nation over, the endearing actor passed away at the age of 88 on 3rd December, 2011 at the Washington Mayfair Hotel in London following a cardiac arrest. Born on 26th September, 1923 in the Gurdaspur district of pre-partition Punjab, he was the third of four brothers and had a younger sister. He began his illustrious acting career, spanning almost 6 decades, in 1946 with Prabhat Films’ Hum Ek Hain. It’s on the sets of this film, that he began his life long friendship with Guru Dutt. In 1949 he opened his own production company, Navketan Films, which would go on to produce and contribute many gems to the Indian film industry, such as Baazi, which was its inaugural film, to ground-breaking films such as Kaala Paani (1958), Hum Dono (1960), Tere Ghar Ke Samne (1963) and Guide (1964). His films were regularly nominated for Filmfare Awards and he himself won the Best Actor award twice for Kaala Paani and Guide. In addition he was also honoured with the Dadasaheb Phalke award, which is India’s highest award for cinematic excellence in 2002 and had been awarded the Padma Bhushan in 2001.

Frequently compared to Gregory Peck, Dev Anand held his own in an era of constant competition from the likes of the immensely talented Raj Kapoor and Dilip Kumar. Infact he developed an exclusive niche for himself, and there was no one in Bollywood who could quite emulate his unique mannerisms or the depth of his acting. Women adored and loved him for his grandiosity, while men wanted to be like him. To quote Shekhar Gupta, the editor of Indian Express, “We all also know that he romanced three generations of Indian women. My mother loved him, and my daughter adored him. And women of my generation, well!”

His most famous liaison was with singer-actress Suraiya who he met in 1948 when he was paired opposite her in the film Vidya. However, they were unable to consummate their relationship due to religious differences and Suraiya’s family being orthodox and conservative. He eventually married Kalpana Kartik (aka Mona Singh) who made her debut in Navketan’s first venture Baazi. However, it was during the shooting of Taxi Driver in 1954, that the couple fell in love and then subsequently married in a quiet ceremony. They bore a son, Suneil Anand in 1956 and then a daughter, Devina.

Image of Dev Anand with Madhubala

He is perhaps the sole actor credited with launching and establishing the careers of most of his leading ladies from Kalpana Kartik to Zeenat Aman. In addition, actresses like Waheeda Rehman and Hema Malini owe it to him for pushing their careers to the stratospheric levels that they eventually achieved. In the 1970s his directorial ambitions took flight even though his first directorial venture Prem Pujari was a flop. However, Hare Rama Hare Krishna in 1971 turned out to be one of the biggest hits of the Indian film industry and made an overnight sensation out of Zeenat Aman. He later also launched Tina Munim’s career in the 1978 film Des Pardes. He directed a total of 19 films with his last film Chargesheet having been released as recently as September of this year, out of which 7 were commercially successful. Despite being credited with launching the careers of many a star, Dev Anand and his work has been widely lauded by critics with most of them describing his directorial ventures as well ahead of their time. His movies were also revered for their melodious, titillating music. In September, 2007 he also released his autobiography “Romancing with Life”.

Having been variously termed as evergreen, flamboyant, debonair, energetic and romantic, Dev Anand’s demise has left a gaping hole in the Indian film industry and in the hearts of millions of his followers. He was one of the first actors of Bollywood to embody a sex appeal and mystique that made him the heartthrob of women of all generations, a rare feat in that time and age. As he himself told Shekhar Gupta, “A star is always a star, Shekhar, and a star has to be always predictable. You are too simple to understand this. Once you become a star, you have to lead a star’s life forever. Stardom is like your skin. You either lose it, or die in it.”

Dev Sahab did it like no one else. His swagger, mannerisms, awkward dance moves, hairstyle, had the whole nation enthralled. From the innocent, charismatic architect in Tere Ghar Ke Samne to the tortured Raju in Guide, he had us all experience the spectrum of emotions he went through. There has never been another one like him and never will be. He is an irreplaceable legend, someone to look upto with utter and absolute reverence. The world will miss Dev Sahab and will always love him!

Deflecting an asteroid impact – The Technical Feasibility

Asteroid Deflection Strategy

Asteroid deflection strategies have been a topic of interest for those enamoured with space studies for ages galore. From NASA scientists to ordinary people they’ve garnered everyone’s attention. Simply defined, asteroid deflection strategies are the “planetary defense” methods[ref]http://en.wikipedia.org/wiki/Asteroid-impact_avoidance[/ref] using which these near-earth objects (NEOs) are diverted thereby preventing catastrophic occurrences on earth, ranging from tsunamis to impact winters (by placing large quantities of dust into the stratosphere, blocking sunlight)[ref]http://en.wikipedia.org/wiki/Asteroid-impact_avoidance[/ref]. While the probability of such an event occurring any time soon is deemed scant, certain recent events such as Shoemaker-Levy 9 have created enough headlines to get people wondering.

Spotting an incoming asteroid

About 90% of NEOs greater than 1 kilometer in diameter have been surveyed by NASA. On a scale of 1 to 10, a 1 kilometer diameter asteroid is deemed to be the least destructive while a 10 kilometer diameter asteroid is considered catastrophic enough to extinguish all life on earth. These survey programs funded by the NASA have been christened “Spaceguard”. Their aim is to attempt to detect and document all asteroids including and exceeding 140 meters in diameter by 2028.

Deflection strategies

Nuclear attack

Asteroid Nuclear Deflection

This is often considered the easiest and quickest method. This can be done in one of two ways. A nuclear explosion can be instituted around, on or beneath the surface of an asteroid with the resulting blast evaporating part of the object and throwing it off course. This is a form of nuclear pulse propulsion[ref]http://en.wikipedia.org/wiki/Asteroid-impact_avoidance[/ref]. However, one can never be certain whether the NEO has been broken into small enough pieces to completely avoid harm. Fracturing a 10 kilometer asteroid into a six kilometer and four kilometer asteroid is great, but they might still be on target for our lovely little planet and carry worldwide devastation in tow[ref]http://io9.com/5861790/how-to-deflect-an-asteroid-attack[/ref]. An alternative method is to have a series of small bombs explode alongside the asteroid but at a distance enough to not fracture the object. The relatively small forces from any number of nuclear blasts could be enough to alter the object’s trajectory enough to avoid an impact[ref]http://en.wikipedia.org/wiki/Asteroid-impact_avoidance[/ref]. A key factor however is to do so well in advance so as to have the maximum impact.

Kinetic energy effect

Asteroid Deflection Kinetic Energy

This works through the impact of a gigantic, non-explosive object, such as a spacecraft or another NEO, a collision with which to alter the course of the asteroid. This strategy is being pioneered by the European Space Agency using a carrier craft and an impactor that can be released on command.

Using a gravitational tractor

Asteroid Deflection Gravitational Tractor

Proposed by Edward T. Lu and Stanely G. Love, this method involves altering the natural course of an asteroid slowly over a period of time sometimes spanning years. The idea is to have a gigantic heavy unmanned spacecraft hover over an asteroid and divert it from its orbit through the simple mechanics of gravitational attraction. The spacecraft would attract the asteroid towards itself and thus deflect it from its original path. While slow, this method has the advantage of working irrespective of the asteroid composition or spin rate – rubble pile asteroids would be difficult or impossible to deflect by means of nuclear detonations while a pushing device would be hard or inefficient to mount on a fast rotating asteroid[ref]http://en.wikipedia.org/wiki/Asteroid-impact_avoidance[/ref].

Attach a rocket

Based upon a proposal of theoreticians at Johns Hopkins University, attaching a rocket to an asteroid would propel it off of its path enough to avoid an impact with earth. Another method is termed the Madmen approach, in which a series of disassembles are docked on to the asteroid which then use the asteroid to create small pebbles which are ejected away from the asteroid. The presumed advantage is that it would take only weeks or months to reduce asteroid mass and velocity using this method and it would act as a safe alternative to chemical and nuclear explosives.

Conclusion

It would be safe to say that it would be in humanity’s interest for several countries to have contingency plans and alternative methods ready in the unlikely event of an asteroid attack occurring anytime soon. Russia has some nascent plans in store while the European Space Agency plans to test its kinetic energy method on a non-threatening asteroid in 2015. In addition, NASA’s constant documenting of NEOs along with the search for effective deflection strategies should let us sleep easy at night.

An Independent look on Mullaperiyar

The Mullaperiyar Dam

The issue of Mullaperiyar Dam has been alive now for quite some time. The historical background and the intension of the formulators are clear to the people at large. Though it involves versatile technicalities, what I have gathered is that a viable solution can be had to the problem. We should not forget that the dam was built by the British before independence. The agreement between the two states, strengthening its relationship with each other, much water has flown under the dam. When the dam was built, the upper limit of water level was fixed at 120 ft. Then spillways were built for controlling the rise of water level adjacent to the dam. These spillways help the flow of water into the state of Kerala when the water level tends to rise above 120 ft.

Unfortunately, there has been a gradual manipulation done by the neighboring state, wherein they had a tactical approach. The spillways were filled with sand and upon which mortar was used to make it concrete. Thus, the purpose of spillways was defeated and they virtually became defunct. Moreover, on one side of the dam unauthorized wells were constructed through which huge pipes were drawn to elicit water from the dam. The immediate solution to check the rise of water in the dam is to perfect the spillways and make it functional.

This will be possible if efforts are made by both state governments without compromising their bilateral relationships. For this purpose, the central government has to perhaps intervene. I do not ignore the fact that the subject matter is subjudice and the Hon’ble Supreme Court is in seizin of the matter. Immediate steps are necessary to apprise the central government of the factual position so that an international catastrophe can be avoided.

The experts or the committee of experts must be able to tell us a viable solution to overcome the present crisis rather than confusing the people at large. One cannot even imagine the depth of fear and agony the nearby inhabitants are undergoing. Those who are cozy comfortable and residing out of the danger zone may not be equated with those who are likely to be affected by the imminent danger.

Is it not true that our neighboring state has had much more advantages after the dam was built year ago? There is a corollary to the issue i.e. a state, which is really benefitted, must look into the physical safety of the dam and security of the people who are otherwise affected in the event of a calamity. Instead, what we see here is an unscientific approach and an adamant attitude which would wither away all possible avenues to sort out the issue.

Fatal Cracks on the Dam

This can be checked bi-focally. First, is that the central government may lay its hands on a war footing and resolve the issue without compromising the relationship of both the states and at the same time permitting the states to exercise their powers guaranteed by the constitution. Secondly, the Hon’ble Supreme Court may pass stringent orders emphasizing the approach that may be taken by the central government vis-à-vis the approach to be taken by the state governments.

In both these cases, the prime factor is time. If delay occurs in arriving at a viable solution, it may result in a very unpleasant situation or a situation beyond our comprehension. Let us hope for the best!

Elenin and Levy – More Warnings from Nature?

Recent activities in the sky have sparked interests in the NEA Research world as news on three potentially hazardous objects viz asteroid 2005 YU55 and the comets ElEnin and Levy hit the headlines in the past few months. Discoveries like these usually cause panic and often incredible and funny speculations and assumptions. Many are already raising questions as to whether we should be concerned or not. The following video shows some of the potentially hazardous asteroids on close encounter with Earth.

As mentioned in my previous article, 2005 YU55 will pass as close as 0.85 lunar distances or roughly 200,000 miles from earth between November 3 and 13 this year. The closest approach will be on November 8 at 07:13 UT. Though close, there is nothing to be concerned as per the latest reports.

Image of Elenin as seen by STEREO Spacecraft on August
Elenin as seen by STEREO Spacecraft on August – Courtesy NASA

Named after its discoverer, as is tradition, comet Elenin also known as C/2010 X1 to the International Astronomical Union was discovered by Russian astronomer Leonid Elenin on December 10, 2010 using the International Scientific Optical Network’s robotic observatory near Mayhill, New Mexico. It is as a small, icy Solar System body. It should not confused with rogue planets or brown dwarfs or the alleged Tyche or Nibiru. During the time of its discovery, it was roughly 647 million km from the Sun between Jupiter and Saturn’s orbits. Classed as a long period comet, it takes more than 11,600 years to make a single orbit of the Sun and was discovered during one of its rare solar visits.

In its closest approach to the Sun, Elenin will pass at 0.48 AU on September 10 2011. The chances of collision with the Sun is just speculation as is the passage between Earth and Moon. On October 16 2011, it will pass closest to Earth at 34.9 million km or 0.233 AU from us which is approximately 90 times further than one lunar distance. Except for experiencing some possible tail debris on November 1 as Earth enters the tail of ElEnin, there won’t be any major effects on Earth unlike false claims like earthquakes caused by its gravitational effect since the mass of its nucleus which is about 20 billion tonnes is too small to cause major changes on the Earth or the Moon. Thus, there is not much to be expected of Elenin though some astronomers are concerned since it is speeding up as it closes in on the Sun.

Comet Levy P/2006 T1 was discovered by David Levy visually using a 0.41-m reflecting telescope, as it passed about 40′ to the north of Saturn just before dawn at around 12h UT on Oct 2, 2006 from his Jarnac Observatory near Tucson, AZ. It was added to the NEO Confirmation page, roughly 8 hours later marking David’s 22nd discovery. His last discovery was the comet Takamizawa-Levy, 12 years ago in April 1994. Its astrometry revealed that it is a short period comet approaching the Sun a little over once every 5 years (5.24 years) with perihelion distance placing it close to the position the Earth occupies in late December. On 2006 Oct 27 at about 03:30 UT, Levy only about 1′ north of the nucleus of the bright galaxy NGC 3521 in Leo.

Image of Comet Levy P2006T1 and NGC 3521 - Coutesy NASA
Comet Levy P2006T1 and NGC 3521 – Coutesy NASA

During its 2006 passage, it achieved an apparent magnitude of ~9.5. Though believed to have been recovered on 03 June 2011 at magnitude 19.8, the recovery was never confirmed by other observatories and the comet was never observed since 01 December 2006 since it only has a confirmed observation arc of 60 days. The next perihelion is calculated to be on 11 January 2012 at 1.007 AU from the Sun. The predicted perigee on 2012-Jan-20 is between 0.15 to 0.20 AU with nominal at 0.18 AU. The predicted apparent magnitude in 2012 might be 7 with elongation of 90°. It is said that Levy will go past above us at a rate faster than our own planet’s orbital velocity on January 29.

Recently a warning was issued by former NASA consultant and US space expert Richard C. Hoagland that Elenin, is under “intelligent control” and heralds a warning to all humanity of a greater global catastrophe. NASA space scientist David Morrison has reported pretty much the same though he has added that these asteroids and comets will pass at safe distances from Earth. Interestingly, some scientists had previously speculated that the two distinct rows of 8 small circular objects trailing Elenin were UFO’s belonging to an as yet unidentified “extraterrestrial civilization.” Though supported by Hoagland, this claim seems to be just fanciful (or wishful) thinking. In any case, these three objects are not going to hit us or cause any significant global catastrophe as feared by many.

I wanted to include more spectacular pictures, but strangely WordPress is not agreeing with me today. I will try to add them at a later time.

Sources:
http://en.wikipedia.org/wiki/P/2006_T1_(Levy)
http://www.armaghplanet.com/blog/10-facts-you-need-to-know-about-comet-elenin.html
https://theboldcorsicanflame.wordpress.com/2011/07/page/8/
http://innidra.wordpress.com/2011/08/27/asteroids-comets-earth%E2%80%99s-close-encounters/
http://www.birtwhistle.org/GalleryC2006T1.htm

Apophis! – Earth’s death knell?

Image of Apophis
Image of Apophis as a snake in Egyptian Mythology

Egyptian mythology has a character called Apophis which was an ancient spirit of evil and destruction, a demon determined to plunge our world into eternal darkness. Astronomers reason that the name befits a menace that is currently hurling towards Earth from outer space.

Scientists for the past few years have been monitoring a 390 metre wide asteroid which is currently classified under the “Potentially Hazardous Objects” category because of its calculated collision course with the planet. Governments have already been alerted to take necessary actions to avoid any catastrophe that might arise if this rock collides with our planet.

According to an estimate by NASA, an impact from Apophis, which is scheduled to take place on April 13 2036, would generate over 100,000 times the energy released in the nuclear blast over Hiroshima. Thousands of square kilometres from the impact site would receive the direct effect of the impact and the rest of the earth will see the effects of huge amounts of dust released into the atmosphere.

Image of 99942 Apophis
99942 Apophis – Courtesy Wikipedia

Scientists insist on every Near Earth Objects meetings that there is very little time left to decide and act since the technology required to thwart an asteroid would take decades to design, test and build.  Meteorite experts say that it is a question of when and not if such an object will collide with Earth. A meteorite of the size of 1 km and above will cause mass extinction to species inhabiting our planet including us. The possibility of such collisions is in every hundred million years and it seems we are already overdue for a big collision.

Apophis has been a concern since December 2004 after astronomers projected the orbit of the asteroid into the future and found that the odds of it hitting the Earth is alarming. It was predicted that if it missed Earth in its first approach to Earth in 2029, then the next approach in 2036 might most certainly end in a collision. The object currently has an Aphelion of 1.0987 AU, Perihelion of 0.74604 AU, Semi-major axis of 0.92241 AU, Eccentricity of 0.19121 and Orbital period of 323.58 d or 0.89 a. It has an Average orbital speed of    30.728 km/s, Mean anomaly of 339.94°, Inclination of 3.3315°, Longitude of ascending node of 204.43° and Argument of perihelion of 126.42°.

Image of Radar Image of Apophis
2005 Arecibo Radar Image of Apophis – Courtesy NASA

Currently Apophis is placed at 4 out of 10 in the Torino Scale which measures the threat posed by an NEO where 10 is a certain collision that causes global catastrophe marking it the highest for any asteroid in recorded history. However, the collision in 2029 was eventually ruled out as more data poured in.

Astronomer Alan Fitzsimmons of Queen’s University, Belfast said that Earth’s gravity will deflect the asteroid on 2029 and that there is a small possibility of the asteroid moving through a region in space called the keyhole. If that happens, the chances of a collision during its next pass in 2036 will be even higher.

There is no shortage of ideas as to how to deflect asteroids like these. Even dangerous technologies like nuclear powered spacecraft is under consideration. The Advanced Concepts Team at the European Space Agency is leading the effort in designing a range of satellites and rockets to nudge these potentially hazardous objects. According to Prof Fitzsimmons, the advantage of nuclear propulsion is the amount of power it generates though it has not been tested so far. Solar electric propulsion, another promising idea is already being used by several spacecrafts giving us hope that projects like these would work.

Another interesting method favoured by ESA is the proposed Don Quijote mission which intends to send two spacecrafts at the asteroid. One of them called Hidalgo is supposed to collide with the asteroid and the other called Sancho is supposed to measure the deflection caused by the collision. The test launch is supposed to take place in 2013. Another idea is to use explosives on the asteroid but no astronomer has so far supported the idea since if the explosion takes place close to impact, we might have several fragments hitting us than one thereby increasing the area of damage.

Image of Apophis Path of Risk
The path of risk where Apophis may impact in 2036 – Courtesy Wikipedia

Currently we cannot rule out the possibility of the 2036 impact. However, we need to get our next chance in making an observation of this object which unfortunately will not come until 2013 when we can use radar observations and work out possible future orbits of this asteroid more accurately. NASA argues that the final decision of what needs to be done has to be made at that stage.

Astronomers like Fitzsimmons and Yates say that the preparation should start before 2013 itself. In 2029, we will know for sure whether the object will hit us or not. However, if the worst case scenario turns out to be true and if Earth is not prepared, then it will be too late. Hence we cannot wait until 2029 and start preparing now itself.

New planet discovered in trinary system – Another milestone in exoplanet research!

Image of Hot Jupiter
Most exoplanets are Hot Jupiters

Though the number of extrasolar planets continued to grow over the years, exoplanet researchers were sceptical about existence of planets around multiple star systems since it was suspected that if the stars are not sufficiently farther apart, the constantly varying gravitational force would eventually tug the planet out of orbit. However, recent discoveries of planets in such star systems have proven this hypothesis otherwise.

Planetary scientists last week announced the discovery of a new planet in the HD 132563 trinary star system in the constellation Auriga after a 10-year long study of the system which also made several other discoveries. The system consists of two stars with masses equivalent to the mass of our sun orbiting around each other at 400 AU. The main star of the system called HD 132563A is itself a binary star making it a trinary star system. According to the team led by Silvano Desidera of the Astronomical Observatory in Padova, Italy, this fact was not previously known about the system which was initially considered to be a binary.

Image of HD188753 Orbit
Orbit of HD188753 – Courtesy NASA

This new planet orbits the secondary star in the system called HD 132563B and was discovered spectroscopically using the SARG (Spettrografo Alta Risoluzione Galileo) at Italian Telescopio Nazionale Galileo or TNG. It is estimated that the planet is at least 1.3 times the mass of Jupiter and orbits around its parent star at a mean distance of 2.6 AU with a moderately high eccentricity of 0.22. The team has tried to image the planet directly using adaptive optics  since they could not initially rule out the detection as an instrument effect in the star’s glare.

This discovery brings the total number of planets discovered in multiple star systems to eight. Though the number is small, it seems planets can be commonly found orbiting around more remote members of trinary star systems for good periods of time. The age of the H132563 system is estimated to be between 1-3 billion years in the shorter end and up to 5 billion years. The two estimates have been drawn by measuring the amount of stellar activity and lithium (which decreases with time) and fitting the mass and luminosity onto isochrones respectively. Either way, the planetary system is dynamically stable.

Image of Gliese 667 C
The “Super-Earth” Gliese 667 C – Artist’s Impression

The team has suggested that based on these eight discoveries, it is possible that the occurrence of planets on remote members of multiple star systems may be just as common as planets around wide binaries or even single stars. The Extrasolar Planets Encyclopaedia thus received its 565th member. The HARPS (High Accuracy Radial Velocity Planet Searcher), the spectrographic component of the European Southern Observatory’s 3.6 meter telescope in 2009 discovered a “Super-Earth” in orbit around Gliese 667C, the third star in multiple system located in the constellation Scorpius. This earthlike planet is 5.7 times the mass of Earth and revolves around its parent star, a red dwarf, every seven days.

Astronomers celebrate Neptune’s Birthday!

Image of Neptune Planet NASA
Image of Neptune showing the Great Dark Spot – Courtesy NASA

Neptune turned “one year” old yesterday when it completed its first revolution around the sun since its discovery 165 years ago. Astronomy world celebrated this event as Neptune completed its one year which is 164.79 earth years yesterday. Named after the Roman Sea God, the 8th and last planet of our Solar System, Neptune’s location was mathematically predicted and discovered by Urbain Le Verrier, John Couch Adams and Johann Gottfried Galle putting an end to decades old question “Who was tugging on Uranus?”

Galileo observed Neptune on December 28, 1612 and again on January 27, 1613 and recorded the findings in his drawings. However, he is not credited with the discovery of the planet since he mistook Neptune as a distant star that appeared in conjunction with Jupiter. Neptune had turned retrograde on the day when Galileo discovered it, however, according to physicist David Jamieson, Galileo was at least aware that the “star” he discovered moved relative to the fixed starts.

Substantial deviations from astronomical tables of Uranus’s orbit published in 1821 by French astronomer Alexis Bouvard was subsequently observed leading him to hypothesise that an unknown body was perturbing the orbit of Uranus through gravitational interaction.  British astronomer John Couch Adams in 1843, began work on Uranus’s orbit using the data sent to him by the then Astronomer Royal Sir George Airy through James Challis, the then Cambridge Observatory director. His mathematical work through 1845-46 produced several estimates of the existence a new planet.

Image of Neptune's Orbit
Neptune’s Orbit compared to other planet – Courtesy Wikipedia

During the same period, French astronomer Urbain Le Verrier independently developed his own calculations about the new planet but did not stimulate enthusiasm in his fellow astronomers. In June 1846, Sir George Airy, upon seeing the similarity of Le Verrier’s first published estimate of the planet’s longitude to that of Adams’s estimate, Airy persuaded James Challis to search for the planet though the search that lasted throughout August and September of that year did not produce any results.

Meanwhile, a letter was sent to the German astronomer Johann Gottfried Galle of Berlin Observatory by Le Verrier requesting him to search for the new planet using the observatory’s refractor. A student at the observatory, Heinrich d’Arrest suggested to Galle that they might be able to make the discovery if they compared the chart drawn about the region predicted by Le Verrier and with the current sky to seek the displacement characteristic of the planet as opposed to a fixed star.  It worked and that very evening on September 23, 1846, Neptune was discovered within 1° of where Le Verrier had predicted and about 12° from Adams’ prediction. James Challis later realised that he did observe the planet twice in August but failed to identify it due to his casual approach to the work.

There have been much debate between France and Great Britain as to who should get the credit of the discovery of the planet. However, it was decided through international consensus that both Adams and Le Verrier should be credited equally even though to this day there are people who do not credit Adams with the discovery.

Image of Neptune by Hubble
Neptune shot by Hubble at four time intervals – Courtesy NASA

Neptune is 2.8 billion miles from the Sun which is about 30 times farther than Earth making it slow and freezing cold.  The image shows the planet in four hour intervals within Neptune’s 16-hour day. The white fluffy streaks are clouds, but not of the Earth variety. Due to the low ambient temperature of the planet, they are high-altitude swaths of frozen methane. Neptune has a 29-degree tilt, which, like Earth’s tilt of 23-degrees, causes the planet to experience seasons. Currently Neptune is experiencing summer in the southern hemisphere and winter in the north. While a season lasts only a few months on Earth, it lasts up to 40 years on Neptune.

Planetary scientist Dr. Craig O’Neil of Macquarie University says that we still haven’t learned much about Neptune since its discovery.  “It’s location at the edge of the solar system makes it a bit of a black hole from a knowledge point of view,” he says. According to him, the huge distance from the sun makes sun look like a point of light in Neptune no brighter than Venus does from Earth. Most of what we know about Neptune today comes from Voyager 2’s fly-by of the planet in 1989 and the Hubble Space Telescope.

Image of Neptune Rings
Neptune’s Rings shot by Voyager 2 in 1989 – Courtesy Wikipedia

Neptune does have a planetary ring system, though it is less substantial than that of Saturn. The rings may consist of ice particles coated with silicates or carbon-based material giving them a reddish hue. The three main rings are the narrow Adams Ring, 63000 km from the centre of Neptune, the Le Verrier Ring, at 53000 km, and the broader, fainter Galle Ring, at 42000 km. A faint outward extension to the Le Verrier Ring has been named Lassell; it is bounded at its outer edge by the Arago Ring at 57000 km. Observations show that the rings are more unstable than previously thought. Images taken from the W. M. Keck Observatory in 2002 and 2003 show considerable decay in the rings compared to images by Voyager 2.

Most of the atmosphere of Neptune is made of hydrogen, helium and methane. The blue colour supposedly comes from methane absorbing red light. However, Uranus, that has a similar atmosphere is cyan in colour. Scientists are still speculating about the supersonic winds of Neptune which are the fastest in the Solar System since their speed of 2,000 kilometres per hour do not conform to the large distance from the sun.

The Sun can’t be powering what’s happening there. Given Uranus has fairly mild winds, Neptune’s dynamics are a mystery. One idea is that if you put methane under enough pressure deep in Neptune’s atmosphere, it could convert to diamond which would fall as rain. This conversion process releases heat which could power the winds. That’s a little more speculative, but speculation is all we’ve got, ” says Dr. O’Neil.

Image of Neptune's Moons by Hubble
Neptune’s Moons by Hubble – Courtesy NASA

Shown above is a composite image of Hubble shots stitched together by NASA. You can see multiple moons within the same orbit due to the time lapse between shots. In order to get the true hue of Neptune’s atmosphere, NASA took numerous photos with three different colour filters. Over 30 moons have been discovered orbiting Neptune but the majority orbit farther away to fit into this shot.

Spacecraft captures sungrazing comet’s demise – A historical event!

 

Image of Sungrazing Comet's Demise
Sungrazing Comet’s Demise Captured by SDO and SOHO – Courtesy NASA

Scientists witnessed an extraordinary event for the first time in history when NASA’s Solar Dynamics Observatory stationed in outer space captured a “sun-grazing comet” descending into its demise by melting under the solar heat while grazing the star, reported MSNBC. The high definition imagers of the spacecraft spotted the disintegration that spanned a 15 minute period on 6th July, 2011 which according to SDO officials, has never been observed before.

This marked the first time a comet has been observed in real time as it disappeared though comets have been spotted near the sun before. “Given the intense heat and radiation, the comet simply evaporated away completely,” said the SDO official. In addition to SDO, another NASA-ESA spacecraft called the Solar and Heliospheric Observatory too captured the comet’s demise and recorded the video of the event. SOHO Scientist Bernhard Fleck said, “This is one of the brightest sun-grazers SOHO has recorded, similar to the Christmas comet of 1996.”

Due to the angle of the comet’s orbit, it passed across the first half of the sun and appeared to brighten as it was struck by sun’s hotter particles. Astronomers call these type of comets as sun grazers since their path is extremely close to the sun. They are relatively common and are also known as Kreutz comets, after the 19th century astronomer Heinrich Kreutz who first discovered them. Astronomers believe that these comets initially began as a single, giant comet and then broke apart centuries ago.

2005 YU55 to arrive on November 8, 2011

Discovered by Robert McMillan of the Spacewatch Program near Tucson, Arizona on December 28, 2005, the third near-earth asteroid of 2011, named 2005 YU55 will pass between the Moon and the Earth on November 8. The dark, near spherical rock of 400 meters diameter will move as close as 0.85 lunar distances from earth, confirmed NASA marking it the closest approach to date by an object this large that we know about in advance.

Image of 2005 YU55 Approach
2005 YU55 Approach (Click image to see animation)

Though classified as a potentially hazardous object, 2005 YU55 poses no threat to Earth for at least the next 100 years, reported NASA’s Neart Earth Object Program.

The approach of 2011 MD had created a news earlier this week, when it passed roughly 7,500 miles close to Earth. Earth’s gravity sharply altered its trajectory, preventing it from hitting the planet. However, the International Astronomical Union’s Minor Planet Center in Massachusetts, USA did put out an alert.

According to space scientist Clark Chapman of the Southwest Research Institute in Boulder, Colorado, USA, there is a roughly 50 percent chance of a 30-meter-plus asteroid striking Earth each century. We can expect the next event of this type in 2028 when asteroid (153814) 2001 WN5 will pass within 0.6 lunar distances to earth.

2011 MD leaves warning to Earthlings

Image of 2011 MD Path
2011 MD Trajectory

The Asteroid 2011 MD, discovered on 22nd at the LINEAR near-Earth object survey in Socorro, New Mexico by the amateur Australian Astronomer, Peter Lake flew by the Earth on 27th at a close proximity of 7600 miles which is closer than most satellites. The approach did startle scientists but the prospect of the asteroid burning up in the atmosphere on entry was a relief.

The asteroid flew over the southern Atlantic Ocean, off the coast of Antarctica, during its closest approach. Though a relief now, such rocks are expected to brush Earth every once in six years. As part of the program to identify potentially hazardous objects, scientists are tracking threats like these regularly.

In February, 2011 CQ1, detected just 14 hours before approach passed even closer with a proximity of 3,400 miles making it the closest known flyby asteroid till date. You can view the images of 2011 MD captured by astronomer Tom Glinos and Wireless Beehive website here and here.

2011 MD belongs to a class of asteroids known as Apollo Asteroids that are known to be “Earth Crossers“.  Their orbital semi-major axes are greater than that of the Earth (> 1 AU) and the perihelion distance (q) is less than 1.017 AU. Initially thought of as a space junk, the asteroid gave only a brief period of observability since it appeared close to the Sun during its nearest approach.

The bigger news is that a larger 400m asteroid named 2005 YU55, will make a close return on November 8. However, it is already being tracked by JPL’s NEO scientists in addition to over 75 rocks on the watch list that might make close approach to earth between now and mid-October. Asteroids like these remind us about our vulnerability to an impact and to prepare the technology to thwart such an incident if it happens.