Interesting plans are afoot, to use the Moon’s surface as a mirror for observation:

This mottled landscape showing the impact crater Tycho is among the most violent-looking places on our Moon. Astronomers didn’t aim NASA’s Hubble Space Telescope to study Tycho, however. The image was taken in preparation to observe the transit of Venus across the Sun’s face on June 5-6.

Hubble cannot look at the Sun directly, so astronomers are planning to point the telescope at the Earth’s moon, using it as a mirror to capture reflected sunlight and isolate the small fraction of the light that passes through Venus’s atmosphere. Imprinted on that small amount of light are the fingerprints of the planet’s atmospheric makeup.

These observations will mimic a technique that is already being used to sample the atmospheres of giant planets outside our solar system passing in front of their stars. In the case of the Venus transit observations, astronomers already know the chemical makeup of Venus’s atmosphere, and that it does not show signs of life on the planet. But the Venus transit will be used to test whether this technique will have a chance of detecting the very faint fingerprints of an Earth-like planet, even one that might be habitable for life, outside our solar system that similarly transits its own star. Venus is an excellent proxy because it is similar in size and mass to our planet.

The astronomers will use an arsenal of Hubble instruments, the Advanced Camera for Surveys, Wide Field Camera 3, and Space Telescope Imaging Spectrograph, to view the transit in a range of wavelengths, from ultraviolet to near-infrared light. During the transit, Hubble will snap images and perform spectroscopy, dividing the sunlight into its constituent colors, which could yield information about the makeup of Venus’s atmosphere.

Pretty fascinating stuff!

Credit: Composite Image Data - Hubble Legacy Archive; Adrian Zsilavec, Michelle Qualls, Adam Block / NOAO / AURA / NSF; Processing - André van der Hoeven

It’s time for an awesome galaxy picture, and today’s APOD fits the bill — another treasure dug from the Hubble Legacy Archive! (I’ve uploaded the full version for your viewing pleasure, click the image to view. You’re welcome.)

Close to the Great Bear (Ursa Major) and surrounded by the stars of the Hunting Dogs (Canes Venatici), this celestial wonder was discovered in 1781 by the metric French astronomer Pierre Mechain. Later, it was added to the catalog of his friend and colleague Charles Messier as M106. Modern deep telescopic views reveal it to be an island universe: a spiral galaxy around 30 thousand light-years across located only about 21 million light-years beyond the stars of the Milky Way. Along with prominent dust lanes and a bright central core, this colorful composite image highlights youthful blue star clusters and reddish stellar nurseries that trace the galaxy’s spiral arms. The high resolution galaxy portrait is a mosaic of data from Hubble’s sharp ACS camera combined with groundbased color image data. M106 (aka NGC 4258) is a nearby example of the Seyfert class of active galaxies, seen across the spectrum from radio to X-rays. Energetic active galaxies are powered by matter falling into a massive central black hole.

22 years old, and Hubble still produces gorgeous glimpses into the universe. Enjoy!

Several million young stars are vying for attention in this NASA Hubble Space Telescope image of a raucous stellar breeding ground in 30 Doradus, located in the heart of the Tarantula Nebula. 30 Doradus is the brightest star-forming region visible in a neighboring galaxy and home to the most massive stars ever seen. The nebula resides 170,000 light-years away in the Large Magellanic Cloud, a small, satellite galaxy of our Milky Way. No known star-forming region that is inside our Milky Way is as large or as prolific as 30 Doradus.

The image comprises one of the largest mosaics ever assembled from Hubble photos and includes observations taken by Hubble’s Wide Field Camera 3 and Advanced Camera for Surveys. Hubble made the observations in October 2011. NASA and the Space Telescope Science Institute are releasing the image to celebrate Hubble’s 22nd anniversary.

Five galaxies are better than one! A stunning image from the Hubble Legacy Archive.

The first identified compact galaxy group, Stephan’s Quintet is featured in this eye-catching image constructed with data drawn from the extensive Hubble Legacy Archive. About 300 million light-years away, only four of these five galaxies are actually locked in a cosmic dance of repeated close encounters. The odd man out is easy to spot, though. The interacting galaxies, NGC 7319, 7318A, 7318B, and 7317 have an overall yellowish cast. They also tend to have distorted loops and tails, grown under the influence of disruptive gravitational tides. But the predominantly bluish galaxy, NGC 7320, is closer, just 40 million light-years distant, and isn’t part of the interacting group. Stephan’s Quintet lies within the boundaries of the high flying constellation Pegasus. At the estimated distance of the quartet of interacting galaxies, this field of view spans about 500,000 light-years. However, moving just beyond this field, above and to the left, astronomers can identify another galaxy, NGC 7320C, that is also 300 million light-years distant. Of course, including it would bring the interacting quartet back up to quintet status.

A bonus sparkly Monday post for your viewing pleasure, at the core of NGC 6752!

This sharp Hubble Space Telescope view looks deep into NGC 6752. Some 13,000 light-years away toward the southern constellation Pavo, the globular star cluster roams the halo of our Milky Way galaxy. Over 10 billion years old, NGC 6752 holds over 100 thousand stars in a sphere about 100 light-years in diameter, but the Hubble image frame spans the central 10 or so light-years and resolves stars near the dense cluster core. In fact the frame includes some of the cluster’s blue straggler stars, stars which appear to be too young and massive to exist in a cluster whose stars are all expected to be at least twice as old as the Sun. Explorations of the NGC 6752 have also indicated that a remarkable fraction of the stars near the cluster’s core, are multiple star systems, supporting arguments that star mergers and collisions in the dense stellar environment can create the cluster’s blue straggler stars.

This is an unusual image, a mix of visible light (red) and X-rays (green). It reminds me of a water opal:

Where’s the other star? At the center of this supernova remnant should be the companion star to the star that blew up. Identifying this star is important for understanding just how Type Ia supernova detonate, which in turn could lead to a better understanding of why the brightness of such explosions are so predictable, which in turn is key to calibrating the entire nature of our universe. The trouble is that even a careful inspection of the center of SNR 0509-67.5 has not found any star at all. This indicates that the companion is intrinsically very faint — much more faint that many types of bright giant stars that had been previous candidates. In fact, the implication is that the companion star might have to be a faint white dwarf, similar to — but less massive than — the star that detonated. SNR 0509-67.5 is shown above in both visible light, shining in red as imaged by the Hubble Space Telescope, and X-ray light, shown in false-color green as imaged by the Chandra X-ray Observatory. Putting your cursor over the picture will highlight the central required location for the missing companion star.

Image Credit: X-ray: NASA/CXC/SAO/J. Hughes et al., Optical: NASA/ESA/Hubble Heritage Team (STScI /AURA)

Image courtesy ESA/NASA

I thought I scheduled this post already — I guess I just thought about it REALLY LOUDLY. Saw this image on National Geographic, get a big version on the ESA Hubble website.

A galaxy slightly smaller than our own Milky Way is getting its arm twisted, and a cosmic bully may be to blame.

As seen in a picture released in August by scientists with the NASA/ESA Hubble Space Telescope, one of galaxy NGC 2146′s arms is bent at a 45-degree angle, such that the dense limb has looped in front of the galaxy’s core, as seen from Earth.

The most likely explanation is that the gravity of an unidentified nearby galaxy is disturbing NGC 2146′s arm, causing the galaxy to warp.

Wishing all of my readers a very merry Christmas!

The bipolar star-forming region, called Sharpless 2-106, or S106 for short, looks like a soaring, celestial snow angel. The outstretched “wings” of the nebula record the contrasting imprint of heat and motion against the backdrop of a colder medium. Twin lobes of super-hot gas, glowing blue in this image, stretch outward from the central star. This hot gas creates the “wings” of our angel. A ring of dust and gas orbiting the star acts like a belt, cinching the expanding nebula into an “hourglass” shape.

I suppose one could construe that most spiral galaxies resemble holiday wreaths, but this is a particularly sparkly, full wreath. So there. Enjoy your Wednesday — and the shortest day of the year!

Resembling festive lights on a holiday wreath, this NASA/ESA Hubble Space Telescope image of the nearby spiral galaxy M74 is an iconic reminder of the impending season. Bright knots of glowing gas light up the spiral arms, indicating a rich environment of star formation.

Messier 74, also called NGC 628, is a stunning example of a grand-design spiral galaxy that is viewed by Earth observers nearly face-on. Its perfectly symmetrical spiral arms emanate from the central nucleus and are dotted with clusters of young blue stars and glowing pink regions of ionized hydrogen (hydrogen atoms that have lost their electrons). These regions of star formation show an excess of light at ultraviolet wavelengths.

Tracing along the spiral arms are winding dust lanes that also begin very near the galaxy’s nucleus and follow along the length of the spiral arms. M74 is located roughly 32 million light-years away in the direction of the constellation Pisces, the Fish. It is the dominant member of a small group of about half a dozen galaxies, the M74 galaxy group. In its entirety, it is estimated that M74 is home to about 100 billion stars, making it slightly smaller than our Milky Way.

Image Credit: NASA, ESA, and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration

Credit: ESO/WFI (visible); MPIfR/ESO/APEX/A. Weiss et al. (microwave); NASA/CXC/CfA/R. Kraft et al. (X-ray); Inset: NASA/TANAMI/C. Müller et al. (radio)

Hubble unveiled some amazing time-lapse videos of supersonic jets released by young stars this week; above are some (scary) plasma jets shooting out of a galaxy. I don’t know what this has to do with Labor Day weekend, but here you go anyway. Enjoy.

Jets of streaming plasma expelled by the central black hole of a massive spiral galaxy light up this composite image of Centaurus A. The jets emanating from Cen A are over a million light years long. Exactly how the central black hole expels infalling matter is still unknown. After clearing the galaxy, however, the jets inflate large radio bubbles that likely glow for millions of years. If excited by a passing front, radio bubbles can even light up again after a billion years. X-ray light is depicted in the above composite image in blue, while microwave light is false-colored orange. The inset image in radio light shows newly imaged, never seen-before details of the innermost light year of the central jet.