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This date in science: E=mc2

Image credit: Wikimedia Commons

Albert Einstein in 1905, his “miracle year.” Image via Wikimedia Commons

September 27, 1905. On this date, while he was employed at a patent office, Albert Einstein published a paper titled “Does the Inertia of a Body Depend Upon Its Energy-Content?” It was the last of four papers he submitted that year to the journal Annalen der Physik. The first explained the photoelectric effect, the second offered experimental proof of the existence of atoms, and the third introduced the theory of special relativity. In the fourth paper, Einstein explained the relationship between energy and mass. That is, E=mc2

Moon near Saturn, and approaching Mars, on September 27

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As soon as darkness falls on September 27, look first for the waxing crescent moon. It’ll be shining close to the planet Saturn, especially as seen from the Americas and the islands of the Pacific. In Hawaii and southwestern Alaska, the moon will actually occult – cover over – Saturn at dusk or early evening on September 27.

Young moon returns to the evening sky

Young moon - a waxing crescent in the west after sunset - captured by Spencer Mann in Davis, California on September 25, 2014.

Young moon – a waxing crescent in the west after sunset – captured by Spencer Mann in Davis, California on September 25, 2014.

The moon was rising and setting with the sun in the past few days. Now it’s far enough from the sun’s glare to be visible in the evening sky, shortly after sunset.

Use Cassiopeia to find the Andromeda galaxy

Andromeda_galaxy_via_Cassiopeia

Try star-hopping to the Andromeda galaxy from the constellation Cassiopeia the Queen. In a dark sky, you might even spot this hazy patch of light with no optical aid, as the ancient stargazers did before the days of light pollution.

Moon and Mercury low in west after sunset September 25 and 26

2014-sept-25-26-mercury-spica-multiple-moon-night-sky-chart

Do you live in the Southern Hemisphere, or the northern tropical latitudes? If so, you have a golden opportunity to catch the young lunar crescent bunching up with the planet Mercury and the star Spica as night falls on September 25 and/or September 26. Look for the moon, Mercury and Spica to pop out over the sunset point on the horizon as dusk ebbs into darkness. Not in Southern Hemisphere or tropics? Try it, anyway! Binoculars will help you scan for the pair along the sunset horizon.

Star-hop from Great Square to Andromeda galaxy

The Andromeda galaxy and two satellite galaxies as seen through a powerful telescope. To the eye, the galaxy looks like a fuzzy patch. It’s an island of stars in space, much like our Milky Way. Image Credit: NOAO

Here is the Andromeda galaxy, the large spiral galaxy nearest our own Milky Way. Because the moon will be coming back to the evening sky soon – appearing only as a slim crescent at nightfall – the night sky now is mostly moon-free. That means nightfall and early evening will present a fine time for viewing this deep-sky treasure. Click inside to learn to use the Great Square of Pegasus as a great jumping off point for finding the Andromeda galaxy.

Mars MAVEN spacecraft’s first observations

MAVEN is the first spacecraft dedicated to exploring the tenuous upper atmosphere of Mars.  It entered orbit around Mars on September 22, 2014.  This composite image represents the first observations returned from the craft.  Image via NASA

This composite image represents MAVEN’s first observations of Mars’ atmosphere. Image via NASA

NASA said yesterday (September 24, 2014) that MAVEN – aka the Mars Atmosphere and Volatile Evolution spacecraft – has now obtained its first observations of the extended upper atmosphere surrounding our neighboring planet Mars.

Success! India’s Mars spacecraft enters orbit

In this illustration, India’s Mars Orbiter Mission (MOM) closes in on the Red Planet after a 10-month interplanetary journey, with its Mars Orbit Insertion engine firing. Image credit ISRO

In this illustration, India’s Mars Orbiter Mission (MOM) closes in on the Red Planet after a 10-month interplanetary journey, with its Mars Orbit Insertion engine firing. Image credit ISRO

In its first interplanetary mission, India successfully placed a satellite into orbit around Mars on Wednesday. Congratulations to India!

Water vapor in atmosphere of exoplanet four times Earth’s size

Because no clouds blocked the view, scientists were able to observe water vapor on a Neptune-sized planet for the first time. The smaller the planet, the more difficult it is to observe its atmosphere, and other small planets have been obscured by clouds. The upper atmosphere of HAT-P-11b appears nearly cloud-free, as shown in this artist's depiction.  Image via NASA/JPL/Caltech

Because no clouds blocked the view, scientists were able to observe water vapor on a Neptune-sized planet for the first time. This is an artist’s depiction of the upper atmosphere of that planet, called HAT-P-11b. Image via NASA/JPL/Caltech

Here on Earth, water = life. That’s why astronomers are very excited about a finding of water vapor in the atmosphere of a planet only about four times bigger than Earth. The planet is called HAT P-11b. It’s some 124 light-years. We now know more than 1,800 planets orbiting stars other than our sun, but astronomers say this is the smallest exoplanet in whose atmosphere they’ve been able to identify some chemical components. The journal Nature will publish their findings on September 25, 2014.

Ice crystals don’t melt inside these fish

Image credit: Paul A. Cziko via University of Oregon

Image credit: Paul A. Cziko via University of Oregon

Antifreeze proteins help fish called notothenioids survive in icy Antarctic waters. But in an evolutionary twist, this simple survival solution may be a double-edged sword: The ice crystals in their blood don’t melt as temperatures warm.