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Is it possible to have three eclipses in one month?


Is it possible to have three eclipses in one month? Yes, it’s possible. You can have two solar eclipses and one lunar eclipse in one month. Or you can have two lunar eclipses and one solar eclipse in one month. However, it’s quite rare to have three eclipses in one calendar month. Follow the links inside to learn more about past and future months in which there are three eclipses.

Mars and its atmosphere, seen by MOM spacecraft

Image via Mars Orbiter Mission

Mars from 74,500 kilometers / 46,265 miles. A dust storm is visible in the northern hemisphere. The MOM mission captured this image on September 28, 2914. Image via Mars Orbiter Mission

Two early images from India’s MOM spacecraft. One shows an edge of Mars, with the planet’s tenuous atmosphere above. The other shows the whole planet. Beautiful!

Comet Siding Spring’s close encounter with Mars

One of the most anticipated astronomical events of 2014 is the close passage of Comet C/2013 A1 Siding Spring to the planet Mars on October 19, 2014. The comet’s tiny nucleus, or core, will miss Mars by about 82,000 miles (132,000 kilometers). But what a sight from Mars! The animation above shows Comet Siding Spring moving among the stars (yes, Mars sees the same patterns of stars we do from Earth). It’s the comet as seen from the location of Curiosity rover on Mars, now at the base of Mount Sharp in Mars’ Gale Crater, during Comet Siding Spring’s close flyby on October 19.

A young galaxy in the local universe?

This image from the NASA/ESA Hubble Space Telescope shows a cosmic oddity, dwarf galaxy DDO 68. This ragged collection of stars and gas clouds looks at first glance like a recently-formed galaxy in our own cosmic neighborhood. But, is it really as young as it looks?

The Hubble Space Telescope captured this image of the dwarf galaxy DDO 68. It looks like a recently-formed galaxy in our own cosmic neighborhood, but is it really as young as it looks? The image is made up of exposures in visible and infrared light taken with Hubble’s Advanced Camera for Surveys. Image via NASA/ESA

The nearby dwarf galaxy DDO 68 – only 39 million light-years away – looks to be relatively youthful based on its structure, appearance, and composition. But its nearness to us in space would suggest that it’s not as young as it looks. A cosmic puzzle, inside.

Why is Antarctic sea ice increasing as Arctic sea ice declines?

This map, based on data from the AMSR2 sensor, shows Antarctic sea ice on September 19, 2014. Image credit: NASA

This map, based on data from the AMSR2 sensor, shows Antarctic sea ice on September 19, 2014. Image via NASA

Arctic sea ice continued its long-term decline in 2014. Meanwhile, sea ice on the other side of the planet was headed in the opposite direction. Why?

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

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.

Autumn equinox, cycles of nature and Chinese philosophy


In the Chinese tradition, the autumn season is associated with the color white, the sound of weeping, the emotions of both courage and sadness, the lung organ, the metal element, and a white tiger. Autumn is also connected in Chinese thought with the direction west, considered to be the direction of dreams and visions.

To the Chinese, nature means more than just the cycling of the seasons. Nature is within us and around us, in all things. The basic cycles of nature, as understood by the ancient Chinese, are easily comprehensible by Western students of nature. They ring true. After all, Chinese civilization flourished for 15 centuries before the Roman Empire came to be. Today we know it’s part of Chinese culture to maintain and add to ancient wisdom. In contrast, we in the Western world tend to replace old ideas with new ideas. So – although our Western way of thinking encourages advances in things like technology and economics – the Chinese understanding of natural cycles remains far deeper than ours.

June through August 2014 hottest ever recorded globally

Image Credit: NOAA/NCDC

August 2014 temperature departures across the globe. It was the warmest August since record keeping began in 1880. Image via NOAA/NCDC

The results are in for NOAA, and they show that the combined average temperature for global land and ocean surfaces for August 2014 was a record high, beating out the old record set back in 1998. The June through August global land and ocean surface temperatures were 0.71°C (1.28°F) higher than the 20th century average, making it the warmest such period since record keeping began in 1880. Have you heard the argument that the past 15 years haven’t seen much warming? Those using that argument are – knowingly or unknowingly – dating it back to the extremely warm year of 1998, when an unusually strong El Niño formed. While we haven’t seen as big of a spike in heating as in 1998, the globe continues to warm and records continue to be broken.

Top 10 things you might not know about stars

The sun in extreme ultraviolet, false color green

The sun in extreme ultraviolet, false color green

Here’s a collection of 10 unexpected, intriguing facts about the stars of our universe – including our sun – that you probably didn’t know!