It’s like something out of a Hollywood film or a science fiction novel: a dark star sneaks up on Earth from just outside the Solar System, discovered too late to do anything about it (and really, what could we do?) and plows through the cloud of comets that surrounds the Sun like a haze of icy gnats, sending them flying everywhere… including on collision courses with Earth. Mass hysteria ensues.
Except that this isn’t just a story concept – scientists think this is actually something that happened 70,000 years ago! Minus the mass hysteria, of course… our ancestors were just beginning to settle down in the fertile lands of the Middle East after wandering out of Africa and would have had no idea what was happening at the edges of the Solar System (besides maybe a bright star occasionally flaring up in the night sky.)
I just had to share this beautiful image by ESO photo ambassador Babak Tafreshi; it shows a star-filled night sky above the Chajnantor Plateau on the border of Chile and Bolivia, the site of the Atacama Large Millimeter/submillimeter Array (ALMA) observatory. The site, chosen for its remote location and incredibly clear, dry sky, is one of the best on Earth for observing the most distant objects in the Universe.
The jagged snow features in the foreground are known as penitentes, for their resemblance to the conical hats of Spanish religious group members known as the Nazarenos. They are the result of Sun and wind erosion on high-altitude snow, although the exact process isn’t entirely known.
It’s Hubble’s 25th anniversary in space this year but it seems like we’re the ones getting all the presents! Yesterday NASA released two new high-def versions of the famous “Pillars of Creation” image, and now today there’s this: Hubble’s most detailed image ever of the Andromeda Galaxy!
Containing over 100 million stars it’s not just the best view yet of Andromeda – it’s also the most expansive image ever made with Hubble. Although the galaxy is 2.5 million light-years away it extends across an area larger than the full Moon in the sky, so to create such a detailed mosaic Hubble had to obtain 7,398 images taken over 411 individual pointings! It’s 1.5 billion pixels covering an area over 40,000 light-years across.
According to NASA, it’s “like photographing a beach and resolving individual grains of sand.” Wow!
Check out the full image below:
NASA’s Hubble Space Telescope is celebrating the 25th anniversary of its launch this year and to commemorate the milestone it’s recently turned its gaze (during the course of about 15 orbits) back onto one of the most iconic targets of its career: the “Pillars of Creation,” five-light-year-high columns of cold gas in the process of being sculpted by the winds from hot young stars in the Eagle Nebula (M16), some 6,500 light-years away.
Previously imaged with Hubble in 1995, the Pillars really shine (no pun intended) in this new high-definition image acquired with the telescope’s Wide Field Camera 3, which was installed in May 2009 during STS-125, NASA’s final servicing mission for Hubble.
And in addition to visible-light* wavelengths Hubble’s WFC3 captured the Pillars in infrared as well, which pierces the dense, cold gas to reveal hidden stars inside – as well as turn the structures into eerie ghostlike shapes. Check out that version below:
Back in December of 2001, Saturn’s moon Titan passed in front of two background stars (called an “occultation”) from the point of view of the Hale Telescope at Palomar Observatory. Astronomers used the incredible resolving ability of the 5-meter telescope’s adaptive optics to watch the event, which revealed the diffraction of the stars’ light through Titan’s dense atmosphere as well as allowing them to measure the moon’s stratospheric winds. Check it out above!
Video credit: A. Bouchez, M. Brown, M. Troy et al./Caltech
These days it seems exoplanets are being discovered nearly every week, with “super-Earths”, “hot Jupiters” and “cold Neptunes” being identified (or at least announced as solid candidates) within star systems all around our neck of the galaxy. To top it all off, today the European Southern Observatory announced that an Earth-mass world has now been found orbiting Alpha Centauri B — quite literally the “star next door.”