Saturday, 10 September 2016

             GOODBYE, HUBBLE?

Loved by most, forgotten by few,the Hubble space telescope is still going strong. But for how long?

May, 2009.Astronauts on the space shuttle Atlantis gave the Hubble space telescope one last overhaul.  Hubble, like other long-running NASA missions such as the Spitzer Space Telescope, will be reviewed every two years to ensure that the mission is continuing to provide science worth the cost of operating it. NASA declared it planned to operate it until its instruments finally give out, potentially for another six years at least. Many expected it to go down, but unsurprisingly its 26 year old legacy continues.

The Hubble space telescope (HST) launched in 1990 , was not the first space telescope , but it was the best and most versatile one ever sent. Named after the great astronomer Edwin Powell Hubble, the Hubble soon became a vital research tool and a public relations boon for astronomy, sending wonderful high-res images of the beyond. But the whole operation was not in the least flawless; Initially expected to launch in 1986 , the challenger disaster delayed the launch by a few years.The images returned during the first weeks were blurred ,and this was attributed to an aberration in its primary mirror.


Every 97 minutes, Hubble completes a spin around Earth, moving at the speed of about five miles per second. Telescopes work by collecting more light than the human eye can capture on its own. The larger a telescope's mirror, the more light it can collect, and the better its vision. Hubble's primary mirror is 94.5 inches (2.4 m) in diameter. This mirror is small compared with those of current ground-based telescopes, which can be 400 inches (1,000 cm) and up, but Hubble's location beyond the atmosphere gives it remarkable clarity. Hubble is a type of telescope known as a Cassegrain reflector. Light hits the telescope's main mirror, or primary mirror. It bounces off the primary mirror and encounters a secondary mirror. The secondary mirror focuses the light through a hole in the center of the primary mirror that leads to the telescope's science instruments.
Hubble has been a great contributor in many fields/topics of research such as dark energy, galaxy formation and evolution,
supernovas and extrasolar planets.It has also served as a public telescope and has been used by amateur observers.

 How long Hubble can run also depends on NASA's budget, which is uncertain given the economic challenges in the United States. Hubble's successor, the James Webb Space Telescope (JWST), is currently in the works. NASA hope to keep Hubble running for as long as possible, which is music to the ears of all Hubble fans. And it should, considering that the Hubble space telescope has been a revolution, a masterpiece, you could say.

THE UNIVERSE AND US

Have you ever wondered, how we and the universe around us are related?                                                            
The Big Bang Theory states that you and I are all made up ultimately of the elements of the stars or the matter left over from the huge battle between matter and anti-matter.

Although I believe this fact, I am keen to know how life started its journey 14 billion years ago to exist in present form and to thrive in the future – from these non-living elements like hydrogen, helium and lithium.
The thing that keeps eating my head is that if we are the only planet to have sustained this phenomenal change, how did it happen?

And now that it did happen, let’s thank God and science together for it, as we are the only known living things to have been created out of this wonderful fabric woven by him called space-time.

Now that we are here, it is our duty to try and not to exploit the extraordinary pleasures that are granted to us. But then this will take my topic away to ecology and environmentalism, which are my second favorite topics if given anything to talk about.

Let’s not forget that this talk is on space and not on mother-nature. 
The origins of the universe are a phenomenon that most of the top level astronomers or physicists also are struggling- like me- to give you a detailed description of what it actually is. But of course they can give you a far better explanation than me.   

Space holds many secrets. It contains places where human beings can stretch into spaghetti shapes, or vaporize, or be frozen solid. Earth seems huge to us – after all, it can take you a long time just to travel from one city to another. But fascinatingly Earth is like an atom to the Milky Way itself. Imagine how small would it seem to the entire universe?

Let’s now take the talk to the next level. That is studying each aspect of how are Universe works:

Galaxies

For those who need the simple definition of what it is, 
A galaxy is a family of stars, gas, and dust held together by gravity. 
Much of a galaxy is empty space, with massive distances between stars that are hard to imagine. 
Many galaxies are found in galaxy clusters, with thousands of members. Our galaxy belongs to a cluster of about 30 galaxies called the ‘Local group’.
Galaxies differ enormously in size, shape, and mass, but they do fall into a basic pattern, depending upon their shape (but we don’t know what gives them a peculiar shape!)


Spiral galaxies

These disc-shaped galaxies spin slowly. They look a bit like whirlpools, and often have two arms that curl out from a central bulge. Milky Way is one. 


Barred spiral galaxies

Barred spiral galaxies have arms that wind out from the ends of a central bar of stars rather than from the core.                                          

Elliptical galaxies

These are ball-or egg-shaped and largely made up of old stars. They don’t contain the gas clouds for the formation of new stars.     
                                                             

Irregular galaxies

These have no shape. They contain lots of gas and dust, and many are therefore active nurseries for the formation of new stars.
 

Our galaxy the Milky Way

The solar system is a tiny – tiny! – part of a gigantic spiral galaxy, the Milky Way. This is made up of billions of stars, which look as if they have been sprinkled thickly onto the night sky.

Why is it milky?
Before the invention of the telescopes, people could not see the stars very clearly – they were blurred together in a hazy white streak. The ancient Greeks called this streak a “river of milk” and the Indians called it (and still call it) the “Akashganga”, literary “the Ganges of the sky”. This is how our galaxy became to be known as the Milky Way.       

The Andromeda galaxy

The Andromeda galaxy, also known as Messier 31, is the largest neighboring galaxy to the Milky Way. This photo, a mosaic of ten images captured by the Galaxy Evolution Explorer spacecraft in 2003, shows blue-white regions along the galaxy's arms where new stars are forming and a central orange-white area containing older, cooler stars.
Andromeda is the nearest spiral galaxy to the Milky Way, but not the closest galaxy overall. It gets its name from the area of the sky in which it appears, the Andromeda constellation, which was named after the mythological princess Andromeda. Andromeda is the largest galaxy of the Local Group. Although the largest, Andromeda may not be the most massive, as recent findings suggest that the Milky Way contains more dark matter and may be the most massive in the grouping. The 2006 observations by the Spitzer Space Telescope revealed that M31 contains one trillion (1012) stars, more than the number of stars in our own galaxy, which is estimated to be c. 200-400 billion.


Space Exploration

When you are trying to imagine the vastness of space, consider that Voyager 1, more than just 30 years after it was launched, is just reaching the outer edges of our solar system. Space exploration is just beginning. 

Cassini–Huygens is a joint NASA/ESA/ASI spacecraft mission studying the planet Saturn and its many natural satellites since 2004. Launched in 1997 after nearly two decades of gestation, it includes a Saturn orbiter and an atmospheric probe/lander for the moon Titan, although it has also returned data on a wide variety of other things including the Heliosphere, Jupiter, and relativity tests. The Titan probe — Huygens, entered and landed on the moon in 2005. The current end of mission plan is a 2017 Saturn impact.   The complete Cassini-Huygens space probe was launched on October 15, 1997 by a Titan IVB/Centaur, and after a long interplanetary voyage it entered into orbit around Saturn on July 1, 2004. On December 25, 2004, the Huygens probe was separated from the orbiter. So it took Cassinni about 7 years to reach Saturn.    
                                                                         

Our solar system

A lot many space-probes and missions have been sent out to study the solar system.
The results after 50 years are that we have got a deep knowledge of how it functions. Almost all the planets (and also Pluto) have been examined thoroughly.

Mercury, the closest planet to the sun, and far smaller than Earth, Mercury has blistering hot days, but freezing nights. The nights get cold because Mercury has no atmosphere to trap the Sun’s heat.
It became the smallest planet in the Solar system after Pluto, which was smaller, was reclassified as a dwarf planet.

As Mercury faces the Sun, temperatures reach a sizzling 425˚C, hot enough to melt lead. Mercury is the second hottest planet, after Venus.

Mariner 10 provided close-ups of Mercury that showed a heavily scarred surface. Rather like our moon, this planet has been battered by comets and meteors. 

Many of Mercury’s craters are named after famous painters, authors, and musicians, so you’d find Mozart, Beethoven, Michelangelo, and Bach there.

By
Kunal Kulkarni
2nd Year ECE

Sunday, 28 August 2016

The moon, Venus and Sirius



'We are a way for the cosmos to know itself ' - Carl Sagan

The Moon

The night sky at NITK, Surathkal on December 19th, 2015 turned to be perfect for star gazers. With the technology that we were equipped with, below are a few breath-taking clicks taken from the main building terrace of our institute. 

Figure 1: 60% visible at 11 pm IST, December 19th, 2015, Telescope: BKP2001EQ-5 (Skywatcher), Camera: Sony HX100V, ISO 400, Aperture 200, Shutterspeed F4.0  

 

HX100V, ISO 640, Aperture 160, Shutterspeed F4.5

Venus

Brightest object in the night sky after moon. It can be seen just before sunrise or just after sunset as a bright morning or evening star. At these times, Venus is up to 15 times brighter than the brightest star, Sirius.

 

Taken on December 20th, 2015 - 4:53:14 am IST
Telescope: BKP2001EQ-5 (Skywatcher)
Camera : Lenovo B6000-HV Tablet, ISO 353, Exposure time 1/10, Aperture 2.8, Focal length 3.5 mm


Sirius


The brightest star visible from any part of Earth is Sirius in the constellation Canis Major the Greater Dog. Sirius is sometimes called the Dog Star. The heliacal rising of Sirius marked the flooding of the Nile in Ancient Egypt and the "dog days" of summer for the ancient GreeksThe name "Sirius" is derived from the Ancient Greek Σείριος (Seirios), meaning "glowing" or "scorcher". What the naked eye perceives as a single star is actually a binary star system, consisting of a white main-sequence star termed Sirius A, and a faint white dwarf companion called Sirius B.
Sirius rises late in the dark, liquid sky
On summer nights, star of stars,
Orion's Dog they call it, brightest
Of all, but an evil portent, bringing heat
And fevers to suffering humanity
- Homer (Illiad)

Taken on 19th December, 2015 - 11 PM IST
BKP2001EQ-5 (SKY WATCHER)
Camera : Sony HX100V, ISO 3200, Aperture 4, Shutterspeed F2.8

Jupiter


 Jupiter, the largest planet in the solar system, has 67 moons at least out of which the four Galilean moons are visible in the picture. In 1610, Galileo Galilei discovered the four largest moons of Jupiter (now known as the Galilean moons) using a telescope; thought to be the first telescopic observation of moons other than Earth's, the moons being Io, Europa, Ganymede and Callisto (From left to right in the images below).

With over 400 active volcanoes, Io is also the most geologically active object in the Solar System. 


Europa is a large, dense, icy moon of Jupiter and the smoothest object in our Solar System. Its surface is covered with long, crisscrossing track ways (but few craters) on water ice.

Ganymede is the largest moon of Jupiter, a large, icy, outer moon that is scarred with impact craters and many parallel faults. It is also the only satellite in the Solar System known to possess a magnetosphere. 
 Callisto is the fourth and farthest Galilean moon. It is also one of the most heavily cratered satellites in the Solar System.

  TAKEN ON DECEMBER 20th, 2015 - 4:30 AM IST
TELESCOPE : BKP2001EQ-5 (SKYWATCHER)
Camera : SM-J100H, ISO 400, Exposure time 1/8, Aperture 2.2, Focal length 3.31 mm