Mariner 4 and Mars


Ma4-mosaic_1-2aOn 15 July, 1965, Mariner 4 flew by Mars and sent back the first 22 pictures of a planet other than Earth taken from a spacecraft. This mosaic was assembled from the first two images. 49 years later, we have high resolution images of the surface of Mars from multiple orbiters and robots roaming the surface.

Image Credit: NASA

The Tadpole


The_TadpoleWhen I was a kid, one of the pleasures of spring was going to the creek and catching tadpoles. This bright blue tadpole seems to swim through the inky blackness of space. Catalogued as IRAS 20324+4057, “The Tadpole” is a clump of gas and dust giving birth to a bright protostar, one of the earliest steps in building a star.

There are multiple protostars in the tadpole’s head; the glowing yellow one in this image is the most luminous and massive. When this protostar has gathered together enough mass from its surroundings, it will become a fully-fledged young star.

The intense blue glow is caused by intense ultraviolet radiation from nearby stars. Pressure from that UV sculpts the tail into a long, wiggly shape. The Tadpole spans roughly a light-year from head to tail-tip, and contains gas with about four times the mass of the Sun.

Image Credit: NASA / ESA

Surveyor 3 and Apollo 12


Surveyor3_Apollo12On 17 April, 1967, NASA launched the Surveyor 3 spacecraft on a mission to the lunar surface. 2-1/2 years later, it was visited by Apollo 12 Commander Charles Conrad Jr. and astronaut Alan L. Bean, who took this picture. The Apollo 12 Lunar Module is visible in the background at right. It landed about 600 feet from Surveyor 3 in the Ocean of Storms. Using a surface sampler to study the lunar soil, Surveyor 3 conducted experiments to see how the lunar surface would support the weight of an Apollo lunar module. This moon lander, which was the second of the Surveyor series to make a soft landing on the moon, also gathered information on the lunar soil’s radar reflectivity and thermal properties. It transmitted more than 6,000 photographs of its surroundings back to Earth. The camera and several other pieces of equipment were removed from Surveyor 3 and brought back to Earth for examination.

Image Credit: NASA

New Moon?


new_moonThe Cassini spacecraft has documented the formation of a small icy object within the rings of Saturn that might be a new moon. It may also provide clues about the formation of some of the planet’s known moons.

Images taken with Cassini‘s narrow angle camera show disturbances at the very edge of Saturn’s A ring, the outermost of the planet’s large, bright rings. One of the disturbances is an arc about 1,200 km long and 10 km wide that is roughly 20 percent brighter than the surrounding ring.

The object is not expected to grow any larger, and may even be falling apart, but the process of its formation and outward movement in the ring aids in our understanding of how Saturn’s icy moons, including the cloud-wrapped Titan and ocean-holding Enceladus, may have formed in more massive rings long ago. It also provides insight into how Earth and other planets in our solar system may have formed and migrated away from the Sun.

Image Credit: NASA

A Horsehead of a Different Color


This video presents a visualization of the Horsehead Nebula as seen in infrared light. The central Hubble image has been augmented by ground-based observations from the European Southern Observatory’s Visible and Infrared Survey Telescope for Astronomy (VISTA). The stars distributed in the three-dimensional environment in an approximate and statistical manner. While it’s no 100%-accurate, the computer graphics are intended to be scientifically reasonable.

The Horsehead Nebula is a dark cloud of dense gas and dust located just below Orion’s belt. Visible light shows a strong silhouette resembling a horse’s head as used for a knight in chess. As seen at left with infrared light we can see more deeply into the clouds, revealing a more complex scene. The warm parts of the clouds glow in infrared light, and a dark and relatively featureless scene is revealed as a glowing gaseous landscape.

Video Credit: NASA

El Gordo


This video shows a close-up of the galaxy cluster ACT-CL J0102−4915 nicknamed El Gordo—the “big” or “fat one” in Spanish. It consists of two separate galaxy sub clusters about 7 billion light-years from Earth that are colliding at several million kilometres per hour. The animation was put together using images taken by ESO’s Very Large Telescope and from the SOAR Telescope along with X-ray observations from NASA’s Chandra X-ray Observatory. The X-ray image shows the hot gas in the cluster and is shown in blue. 

Video Credit: ESO / SOAR / NASA

A Solar Flare


The Sun threw off a mid-strenght M6.5 flare on 2 April. It peaked just after 14:00 UTC. This video from the Solar Dynamics Observatory shows the flare in two wavelengths of extreme ultraviolet light: 30.4 nm and 17.1 nm, color coded yellow and red, respectively.

Video Credit: NASA

In Re THEMIS


THEMIS (Time History of Events and Macroscale Interactions during Substorms)  is a mission to investigate what causes auroras in the Earth’s atmosphere. The program is run by NASA/Goddard Space Flight Center and not by the agency just up the road that forgot to buy both vowels.

I have never had any connection to the program.

UPDATE—I found this attempted comment while taking my morning coffee break.TK201404041329ZOf course, the IP address doesn’t belong to Amazon.IPlookup20140404Not only that, it’s not actively assigned.NoMatch

Hi, Neal!

UPDATE—Ooooo! Struck a nerve, have we? This comment just came in attributed to my late mother.TK2014041542ZCan you say “desperation”?

Encountering Hyperion


This movie is a record of the Cassini spacecraft’s first close brush with Hyperion, a chaotically tumbling moon of Saturn. The jagged outlines are indicators of large impacts chipping away at Hyperion’s shape as a sculptor does to marble. The moon is too small to have pulled itself round by its own gravity. Its unusual dimensions are 328 by 260 by 214 km.

Video Credit: NASA

Io’s True Colors


io_truecolorJupiter’s moon Io is one of the weirdest in the Solar System. It’s bright yellow, and this picture is an attempt to show how Io would appear to the average human eye. Io’s colors derive from sulfur and molten silicate rock. The moon’s is constantly being refreshed by a system of active volcanoes. Tides caused by Jupiter’s gravity stretch Io, and the resulting friction greatly heats Io’s interior, causing molten rock to explode through the surface. Io’s volcanoes are so active that they are effectively turning the whole moon inside out. Some of Io’s volcanic lava is so hot it glows in the dark.

Image Credit: NASA

You Can’t See It From Here


Crescent SaturnThis is a view of Saturn partially lit in crescent phase, a view that can only be seen when the object is between the observer and the Sun. From the Earth, we can only see Mercury and Venus in varying crescent phases and Mars and the other outer planets fully lit. Because the Moon can be either between the Earth and the Sun or farther away, we see it go through all the phases from New to Full to New again.

This picture of Saturn was made by the Cassini spacecraft.

Image Credit: NASA

Breaking Up is Hard to Do


asteroid-disintegrationThis series of Hubble Space Telescope images shows the breakup of an asteroid over a period of several months beginning in late 2013. The largest fragments are up to 180 m in radius. The crumbling asteroid, designated P/2013 R3, was first noticed as an unusual, fuzzy-looking object by the Catalina and Pan STARRS sky surveys last September.

Image Credit: NASA

A Seyfert Galaxy


NGC 5793Carl Seyfert was an interesting fellow. Back in the ’50s when I was a kid growing up in Nashville, he was Director of the Dyer Observatory at Vanderbilt University. I met him through the local astronomy club associated with the Nashville Children’s Museum. He was well known around town because he moonlighted as the weatherman for WSM-TV. He was known in astronomical circles for his research on a class of galaxies.

Those galaxies have incredibly luminous centers that we believe are caused by supermassive black holes—black holes that can be billions of times the size of the sun—pulling in and swallowing gas and dust from their surroundings. NGC 5793 is a Seyfert galaxy over 150 million light-years away in the constellation of Libra.

This Hubble image is centered on NGC 5793. This galaxy is of great interest to astronomers for many reasons. For one, it appears to house objects known as masers. Whereas lasers emit visible light, masers emit microwave radiation. The term “maser” is an acronym of Microwave Amplification by Stimulated Emission of Radiation. Lasers emit visible light; masers emit microwave radiation. Maser emission occurs when particles absorb energy from their surroundings re-emit the energy in the microwave part of the spectrum. Naturally occurring masers such as are found in NGC 5793 can tell us a lot about their environment; we see some types of masers in areas where stars are forming. In NGC 5793 there are also intense mega-masers, thousands of times more luminous than the sun.

Image Credit: NASA

The Moon’s North Pole


gigapan_small_str01NASA has created the largest high resolution mosaic of the Moon’s north polar region using images taken by the Lunar Reconnaissance Orbit. The 2-meter-per-pixel images cover an area equal to more than one-quarter of the United States.

A large version of the map has been posted at http://lroc.sese.asu.edu/gigapan. At that site you can zoom in and out, and pan around an area. The map mosaic was constructed from 10,581 pictures and provides enough detail to see textures and subtle shading of the lunar terrain. Consistent lighting throughout the images makes it easy to compare different regions.

Image Credit: NASA/GSFC/Arizona State University

The Monkey Head Nebula


Monkey HeadThe Hubble Space Telescope captured a series of infrared-light images of a churning region of star birth 6,400 light-years away some of which have been stitched together in this mosaic of a small portion of the Monkey Head Nebula The cloud is sculpted by ultraviolet light eating into the cool hydrogen gas.

BTW, Hubble was launched 24 years ago.

Image Credit: NASA

Hubble Nets a Butterfly


Roberts22This cosmic butterfly is the nebula known as AFGL 4104 or Roberts 22. When a star that is nearing the end of its life throws off its outer layers, a nebula emerges as a cosmic chrysalis. Studies of the lobes of Roberts 22 show an amazingly complex structure with numerous intersecting loops and filaments.

A butterfly’s life span here on Earth is a few weeks. Roberts 22 is also transient but on a much longer time scale. It is currently a pre-planetary nebula, a brief phase that begins once a dying star has shed much of the material in its outer layers into space. That phase will end once this stellar remnant becomes hot enough to ionize the surrounding gas clouds causing them glow. About 400 years ago, the star at the center of Roberts 22 threw off its outer shells, forming this butterfly. Soon, on a cosmic scale, the central star will soon be hot enough to ionize the surrounding gas, and Roberts 22 will evolve into a fully-fledged planetary nebula.

Image Credit: NASA

Missed It By That Much


The Sun cut loose with a M-9.3 flare on 12 March from an active region near the Sun’s edge as seen from the Solar Dynamics Observatory. It just missed being an X class flare, the strongest category. The bright flash is the tell tale sign of a flare. The flare was so bright that it caused very bright saturation and blooming above and below the flare region on the satellite’s CCD detector and caused extended diffraction patterns to spread out across the SDO imager. This 15-hour time lapse video shows that a smaller flare preceded this one as well.

Video Credit: NASA

The Sun in January


The Sun rotates and changes as it does. Those changes can range from subtle to dramatic. This time-lapse video assembled from Solar Dynamics Observatory data shows the Sun during the entire month of January. The large image shows the solar chromosphere viewed in ultraviolet light. The smaller images show simultaneous views. The one in the upper right shows the more familiar solar photosphere in visible light. The rest of the inset images highlight x-ray emissions by relatively rare iron atoms located at different heights of the corona.

The Sun takes just under a month to rotate completely, rotating most rapidly at the equator. A large and active sunspot region rotates into view just after the video starts. As the video ends, the same large and active sunspot region comes back into view.

Video Credit: NASA