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Well, the WISE infrared all-sky satellite may be delayed until Monday, but the new infrared southern sky survey telescope VISTA (Visible and Infrared Survey Telescope for Astronomy) right here on Earth has gone online and released its first few gorgeous pictures.

This first one is of the Flame Nebula (NGC 2024), a star-forming region in the constellation Orion. The bright star in the image is the blue supergiant Alnitak, which is the easternmost star in Orion’s belt. Also shown is the reflected glow of NGC 2023 just below center, and the outline of the Horsehead Nebula in the far lower right (it looks a little different than you might normally see it because VISTA is operating in the visible and near-infrared). This image is about half the area of the full VISTA field of view, and is measures about 40 x 50 arcminutes – that’s about half a square degree on the sky , or twice the area of the full Moon.

The VISTA telescope is operated by the European Southern Observatory, and is part of their Paranal Observatory in the Atacama Desert of Northern Chile. It’s sitting just one peak over from the Very Large Telescope, also operated by the ESO. The main mirror on VISTA is a whopping 4.1 meters across (13.5 feet), and has 16 different detectors and a 3-ton camera for a total output of 67 million pixels. This allows for some very detailed images.

Since it’s a near-infrared telescope, it detects heat, and would detect its own heat signature, so the camera is housed in a cooler that keeps it at a chilly -200 degrees Celsius (-328 degrees Fahrenheit), and it’s sealed with the largest infrared-transparent window ever made. VISTA is charged with surveying the southern sky in the visible and near-infrared, and it will do so at a sensitivity that is forty times that of other infrared sky surveys, such as the Two Micron All-Sky Survey. It will be taking in enormous amounts of data to be processed: 300 gigabytes each night, or more than 100 terabytes per year.

Here’s a few more links to the first images released from the observatory to whet your appetite. Click on the links for a zoomable, hi-resolution image. You can be sure to see more like these in the future!

The Fornax Galaxy Cluster, including the barred-spiral galaxy NGC 1365 in the lower right, and the elliptical galaxy NGC 1399 to the left of it.

This image shows a dusty region with over one million stars near the heart of the Milky Way. The dust normally obscures the stars in visible light, but these stars are visible with the infrared eyes of VISTA.

Source: ESO

There once was a galaxy known as ESO 593-IG 008. It was thought to be a relatively mild-mannered galaxy, even though scientists believed it was a collision of two different galaxies; one a barred spiral and the other an irregular galaxy. But now, an international team of astronomers has discovered that it actually is a stunning rare case of three interacting galaxies, with the third galaxy forming stars at a frantic rate.

Using adaptive optics on the European Southern Observatory’s (ESO) Very Large Telescope (VLT), astronomers were able to see through the all-pervasive dust clouds of the object that has been dubbed as “The Bird” because of its resemblance to a winged creature. With the adaptive optics of what’s called the NACO instrument, very fine details were able to be resolved.

“Examples of mergers of three galaxies of roughly similar sizes are rare,” says Petri Vaisanen, lead author of the paper which will appear in the journal of the Royal Astronomical Society. “Only the near-infrared VLT observations made it possible to identify the triple merger nature of the system in this case.”

NACO is the combination of NAOS – Nasmyth Adaptive Optics System that is equipped with both visible and infrared sensors, and CONICA, a Near-Infrared Imager and Spectrograph.

Looking like a bird or a cosmic Tinker Bell, the NACO images show two unmistakable galaxies that form the body and wings of “The Bird.” Astronomers were surprised with the new images that identify a third, clearly separate component that forms the head. This irregular, yet fairly massive galaxy is forming stars violently, at a rate of nearly 200 solar masses per year. It appears to be the major source of infrared luminosity in the system, even though it is the smallest of the three galaxies. The other two galaxies appear to be at a quieter stage of their interaction-induced star formation history. The object is 650 million light years distant but it is quite large with the “wings” alone extending more than 100,000 light-years, or the size of our own Milky Way.

Subsequent optical spectroscopy with the new Southern African Large Telescope, and archive mid-infrared data from the NASA Spitzer space observatory, confirmed the separate nature of the ‘head’, but also added further surprises. The ‘head’ and major parts of the ‘Bird’ are moving apart at more than 400 km/s (1.4 million km/h). Observing such high velocities is very rare in merging galaxies.

“The Bird” belongs to the prestigious family of luminous infrared galaxies, with an infrared luminosity nearly one thousand billion times that of the Sun. This family of galaxies has long been thought to signpost important events in galaxy evolution, such as mergers of galaxies, which in turn trigger bursts of star formation, and may eventually lead to the formation of a single elliptical galaxy.

The galaxy is also designated as IRAS 19115-2124. The ESO is more formally known as the European Organization for Astronomical Research in the Southern Hemisphere.

Original News Source: ESO Press Release:

Tag: ESO

First (of many) Gorgeous Pictures from the New VISTA

It’s a Bird! It’s Tinker Bell! It’sThree Galaxies!