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What if the Moon was colonized?

Vintage Space Album.

Happy leap day!!!

Leap Day…Why Does It Exist?

Once every four years, an extra calendar day is added: a leap day. But why?

The reason for adding leap days to the calendar is to align the calendar year with the actual year – which is defined by the time it takes Earth to circle the sun. It is equal to 365 days, 5 hours, 48 minutes and 46 seconds, or 365.24219 days.

If all calendar years contained exactly 365 days, they would drift from the actual year by about 1 day every 4 years. Eventually, July would occur during the northern hemisphere winter! Wouldn’t that be weird?

To correct (approximately), we add 1 day every 4 years…resulting in a leap year.

By making most years 365 days but every fourth year 366 days, the calendar year and the actual year remain more nearly in step.

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Life on an Icy Moon

Jupiter’s moon Europa is the size of the Earth’s moon, and yet it holds more than twice as much water as all of Earth’s oceans combined. Europa’s salty ocean covers the entire surface, and the crust is completely frozen over because the moon is 780,000,000 km from the sun and has an average temperature of -160 degrees Celsius. The icy moon’s orbit is eccentric, orbiting in an oval instead of a circle, and so Jupiter’s enormous gravitational pull constantly squeezes and stretches the moon, creating constant motion and likely the surface cracks too. This tidal heating generates warmth, which creates a significant chance that this distant ocean is harboring life. Radiation from Jupiter’s magnetosphere could destroy life at shallow depths, but new research suggests that there’s oxygen available in the subsurface ocean that could support oxygen-based metabolic processes. Scientists must now determine how deep such organisms must hide in order to avoid radiation, and therefore how deep we need to go to find them. The icy crust might be hundreds of metres or even kilometres thick, and so sending a probe through the surface would be difficult, but we have to try, because Europa is one of the best potential sources for extraterrestrial life in the solar system.

Read more—could the oceans be too acidic for life?

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

All my high school classmates are getting married and/or having kids.....then here I am with my sugar gliders.

Solar System: Things to Know This Week

1. See Shadows on Jupiter

Jupiter dominates the evening sky this month, rising at sunset and setting at dawn. On the nights of March 14 and 15, Jovian moons Io and Europa will cross the planet’s disk. When the planet is at opposition and the sun shines on Jupiter’s moons, we can see the moons’ shadows crossing the planet. There are actually 11 of these double shadow transits in March.

2. One Year of Dawn at Ceres

NASA’s Dawn spacecraft gently slid into orbit around Ceres just over one year ago, becoming the first spacecraft to reach a dwarf planet. Since then, the spacecraft has delivered a wealth of images and other data that open an exciting new window to this previously unexplored body in the asteroid belt.

3. The Latest from Saturn

Days ago, on Mar. 11, 2016, Cassini’s Ultraviolet Imaging Spectrograph (UVIS) watched as the plume of gas and icy particles from the moon Enceladus passed in front of the central star in Orion’s Belt. Such observations, known as stellar occultations, provide information about the density and composition of the plume.

4. The Equinox is Upon Us

March 20 is the vernal equinox–the start of spring in the northern hemisphere, and the start of fall in the southern hemisphere. During the two equinoxes each year, the line between day and night is vertical, so all over the planet, the length of the day and night are nearly equal. For the rest of the year, the Earth’s tilt angles the line between day and night, culminating with the solstices, in which the poles receive weeks of unending sunshine or darkness depending on the time of year.

5. Up Close with a Comet

Before Rosetta crash lands into comet Comet 67P/Churyumov-Gerasimenko in September, 2016, it will continue taking pictures and detailed measurements of this mysterious comet to study the origin of comets and how they relate to the origin of the solar system.

Want to learn more? Read our full list of the 10 things to know this week about the solar system HERE.

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