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For all your stargazing pleasures

What’s Up for April 2016?

Jupiter, Mars, the Lyrid meteor shower and 2016’s best views of Mercury are all visible in the sky this month.

Jupiter, where our Juno mission will begin orbiting on July 4, continues to shine almost as brightly this month as last. And eagle-eyed telescope viewers will see a transit, a shadow transit, an occultation and an eclipse of Jupiter’s moons- all in one night: April 6-7. 

Io transits first, crossing the planet beginning at 9:52 p.m. EDT. It’s shadow can be seen less than an hour later. 

Next Jupiter occults, or eclipses, Europa as Europa slips behind the giant planet at 10:48 p.m. EDT. At 3 a.m. Europa reappears from its eclipse, dramatically leaving the shadow of Jupiter. 

Ganymede transits the planet beginning at 1:01 EDT April 7.

Check out the other planets in April, too! Mercury is always a challenging object to view, but this month you can spot it after sunset about 10 degrees above the horizon. Through a telescope you can see its phase. It will appear like a tiny crescent moon, with about 1/3 of its disk illuminated.

Mars is finally visible before midnight this month. It rises in the southeast at about 10 p.m. by the end of April. The best observing of Mars will be when it is highest in the sky. This means a few hours before dawn. Its brightness and apparent size increase dramatically this month. By month’s end, Mars appears nearly twice as bright as at the beginning of the month. 

About mid-month you’ll see Mars near its rival in the sky: the similar-colored red supergiant star Antares. The name “Antares” means “equal to or rival of Mars”.

Earth moves almost twice as fast as Mars does, so it often passes Mars in their race around the sun. This causes “retrograde motion”: an illusion we see from our viewpoint on Earth. 

Retrograde motion happens as Earth catches up to Mars, causing Mars to appear slow to slow its eastward motion against the stars. After a few days, when Earth has overtaken Mars, the Red Planet seems to move westward. Eventually, Earth moves far enough around its orbit that Mars appears to be moving eastward again.

April features one meteor shower, the Lyrids. This year the Lyrids are marred by the full moon. The best time to view will be just before dawn on April 23, when the constellation Lyra is overhead and the moon will be near to setting.

With all of these great things to spot in the sky this month, be sure to get outside and look up!

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Andromeda Legend: The Chained Lady

Cassiopeia, Andromeda’s mother, boasted that she was the most beautiful woman in the world, even more beautiful than the gods. Poseidon, the brother of Zeus and the god of the seas, took great offense at this statement, for he had created the most beautiful beings ever in the form of his sea nymphs. In his anger, he created a great sea monster, Cetus (pictured as a whale) to ravage the seas and sea coast. Since Cassiopeia would not recant her claim of beauty, it was decreed that she must sacrifice her only daughter, the beautiful Andromeda, to this sea monster. So Andromeda was chained to a large rock projecting out into the sea and was left there to await the arrival of the great sea monster Cetus. As Cetus approached Andromeda, Perseus arrived (some say on the winged sandals given to him by Hermes). He had just killed the gorgon Medusa and was carrying her severed head in a special bag. When Perseus saw the beautiful maiden in distress, like a true champion he went to her aid. Facing the terrible sea monster, he drew the head of Medusa from the bag and held it so that the sea monster would see it. Immediately, the sea monster turned to stone. Perseus then freed the beautiful Andromeda and, claiming her as his bride, took her home with him as his queen to rule.

Yep, dope haha!

I need them all

These planet pillows are made to look like the planets of our solar system along with the sun and the moon. Now you can feel the cozy warm embrace of space!

More info: http://odditymall.com/planet-pillows

Celestial Wonders- Binary Stars (#1)

The twins of the stellar world are binary star systems.

A binary star is a star system consisting of two stars orbiting around their common center of mass.

When two stars appear close together in the sky as seen from the Earth when viewed through  an optical telescope, the situation is known as an “optical double”.

This means that although the stars are aligned along the same line of sight, they may be at completely different distances from us. This occurs in constellations; however, two stars in the same constellation can also be part of a binary system  

Why study Binary stars ?

Binary star systems are very important in astrophysics because calculations of their orbits allow the masses of their component stars to be directly determined, which in turn allows other stellar parameters, such as radius and density, to be indirectly estimated.

This also determines an empirical mass-luminosity relationship (MLR) from which the masses of single stars can be estimated.

Also,it is estimated that 75% of the stars in the Milky Way galaxy are not single stars, like the Sun, but multiple star systems, binaries or triplets.

The Brightest star in the sky is a binary.

This is true. Sirius (aka the Dog star)  - the brightest star in the sky is actually a binary star system.

When it was discovered in 1844 by the German astronomer Bessel, the system was classed as an astro-metric binary, because the companion star, Sirius B, was too faint to be seen.

Bessel, who was also a mathematician, determined by calculations that Sirius B existed after observing that the proper of Sirius A (the main star) followed a wavy path in the sky, rather than a uniform path.

Sirius can now be studied as a visual binary because, with improving technology and therefore improved telescopes, Sirius B was able to be seen, although not for 20 years after Bessel had correctly predicted its existence.

Black Holes in a binary system ?

Hell Yeah! The term “binary system” is not used exclusively for star systems, but also for planets, asteroids, and galaxies which rotate around a common center of gravity.

However, this is not a trick question; even in star binaries, the companion can be a black hole.

An example of this is Cygnus X-1.

A binary Black Hole system ?

Definitely! A binary black hole (BBH) is a system consisting of two black holes in close orbit around each other.

In fact the LIGO experiment which confirmed the existence of Gravitational waves was able to acquire its data when two Binary Black Holes Collided and merged into one. This phenomenon sent ripples in the fabric of space-time which we call as a Gravitational Wave.

The Universe is amazing huh?

If you found this interesting, check out:

A Denied stardom status - Jupiter

Black Holes are not so Black (Part 3) - Gravitational Waves

It's true I'm a sucker

Space Station Flyover of the Mediterranean : Expedition 46 flight engineer Tim Peake of the European Space Agency

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A Denied stardom status - Jupiter

Of all the planets in our solar system, Jupiter seems to stand out as this massive giants.

When scientists started uncovering the secrets of this mysterious planet, they discovered that Jupiter was probably a ‘star in the making’ during the early years of the solar system.

Jupiter and the sun

Jupiter has a lot in common with the sun than you think.

It is made of the same elements such as Hydrogen and Helium that are found in the sun and other stars!

But it is not massive enough and does not have have the pressure and temperature to fuse the existing Hydrogen atoms to form helium, which is the power source of stars.

How do stars form ?

Stars form directly from the collapse of dense clouds of interstellar gas and dust. Because of rotation, these clouds form flattened disks that surround the central, growing stars.

After the star has nearly reached its final mass, by accreting gas from the disk, the leftover matter in the disk is free to form planets. 

How was Jupiter formed ?

Jupiter is generally believed to have formed in a two-step process:

First, a vast swarm of ice and rock ‘planetesimals’ formed. These comet-sized bodies collided and accumulated into ever-larger planetary embryos.

Once an embryo became about as massive as ten Earths, its self-gravity became strong enough to pull in gas directly from the disk. 

During this second step, the proto-Jupiter gained most of its present mass (a total of 318 times the mass of the Earth).

But sadly soon thereafter, the disk gas was removed by the intense early solar wind (from our sun) , before Jupiter could grow to a similar size.

This destroyed all hopes that Jupiter had on becoming a star

What if it had become a star ?

If Jupiter had become a star,our solar system would have become a binary star system.

A binary star system is those systems having two stars.they both revolve around themselves in their own orbits.

It is interesting to note that most of the solar systems in the universe are binary,triple or higher multiple star systems but our sun is rather unusual.

In other star systems the mass distribution of the stars is equitable, but in ours the sun decided to not let that happen

Why? We have no clue ! Scientists are still trying to fathom these mysterious details of the birth process. But the more we know, the more we learn we don’t know :D

“Apparent magnitude of the Sun as veiwed from the various Planets.” From an 1869 edition of The Atlas of Astronomy by Alexander Keith Johnston.

(David Rumsey Map Collection)

A little upset that Jupiter is missing but still awesome

Star Wars Planets

“Don’t think of night as the absence of day; think of it as a kind of freedom. Turned away from our sun, we see the dawning of far flung galaxies. We are no longer sun blinded to the star coated universe we inhabit.

Diane Ackerman, A Natural History of the Senses (via beautyandtheuniverse)

Solar Analemma for the year 2015 shot at Sulmona, Abruzzo, Italy.

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Planet Saturn and its moons Tethys and Dione were, photographed by the Voyager 1 space probe in November of 1980.

Moon+Saturn

This is what Washington DC would look like if Earth had Saturn’s rings.

Neptune

Neptune, seen from the Keck Observatory in the infrared (wavelength 1.17-1.3 microns), 11 August 2004.  (Program ID N19N2.)

Telescope view of Jupiter and the 4 Galilean moons: Io, Europa, Ganymede, & Callisto.

This is a photo of Saturn’s moon Enceladus - a dynamic ice world.  Its surface shifts on geologic timescales, with vast ice sheets spreading and crashing like tectonic plates. Cryovolcanoes (which is a real term that I did not make up) shoot geysers of water out into space.

Recent readings taken by the Cassini spacecraft suggest that Enceladus has a rocky core and liquid oceans beneath the icy surface.

This picture was taken as Cassini was speeding away from Enceladus in 2008, after skimming just 15 miles above its surface.

Happy Saturnalia!