Milky Way Galaxy Doomed: Collision with Andromeda Pending
Illustration Credit: NASA, ESA, Z. Levay and R. van der Marel (STScI), and A. Mellinger
Explanation: Will our Milky Way Galaxy collide one day with its larger neighbor, the Andromeda Galaxy? Most likely, yes. Careful plotting of slight displacements of M31’s stars relative to background galaxies on recent Hubble Space Telescope images indicate that the center of M31 could be on a direct collision course with the center of our home galaxy. Still, the errors in sideways velocity appear sufficiently large to admit a good chance that the central parts of the two galaxies will miss, slightly, but will become close enough for their outer halos to become gravitationally entangled. Once that happens, the two galaxies will become bound, dance around, and eventually merge to become one large elliptical galaxy — over the next few billion years. Pictured above is an artist’s illustration of the sky of a world in the distant future when the central parts of each galaxy begin to destroy each other. The exact future of our Milky Way and the entire surrounding Local Group of Galaxies is likely to remain an active topic of research for years to come.
NASA APOD 4 June 2012
SpaceX Dragon Approaches the International Space Station (NASA, 05/25/12) by NASA’s Marshall Space Flight Center on Flickr.
Via Flickr:
The SpaceX Dragon commercial cargo craft approaches the International Space Station on May 25, 2012 for grapple and berthing. Expedition 31 Flight Engineers Don Pettit and Andre Kuipers grappled Dragon at 9:56 a.m. (EDT) with the Canadarm2 robotic arm and used the robotic arm to berth Dragon to the Earth-facing side of the station’s Harmony node at 12:02 p.m. May 25, 2012. Dragon became the first commercially developed space vehicle to be launched to the station to join Russian, European and Japanese resupply craft that service the complex while restoring a U.S. capability to deliver cargo to the orbital laboratory. Dragon is scheduled to spend about a week docked with the station before returning to Earth on May 31 for retrieval.
Image credit: NASA/JSC
A Sagittarius Triplet
Image Credit & Copyright: Martin Pugh
Explanation: These three bright nebulae are often featured in telescopic tours of the constellation Sagittarius and the crowded starfields of the central Milky Way. In fact, 18th century cosmic tourist Charles Messier cataloged two of them; M8, the large nebula left of center, and colorful M20 on the right. The third, NGC 6559, is above M8, separated from the larger nebula by a dark dust lane. All three are stellar nurseries about five thousand light-years or so distant. The expansive M8, over a hundred light-years across, is also known as the Lagoon Nebula. M20’s popular moniker is the Trifid. Glowing hydrogen gas creates the dominant red color of the emission nebulae, with contrasting blue hues, most striking in the Trifid, due to dust reflected starlight. This broad skyscape also includes one of Messier’s open star clusters, M21, just above and right of the Trifid.
NASA APOD 1 June 2012
Venus Viewed by Hubble by NASA Goddard Photo and Video on Flickr.
Via Flickr:
This is a NASA Hubble Space Telescope ultraviolet-light image of the planet Venus, taken on January 24 1995, when Venus was at a distance of 70.6 million miles (113.6 million kilometers) from Earth. Venus is covered with clouds made of sulfuric acid, rather than the water-vapor clouds found on Earth. These clouds permanently shroud Venus’ volcanic surface, which has been radar mapped by spacecraft and from Earth-based telescope. At ultraviolet wavelengths cloud patterns become distinctive. In particular, a horizontal “Y”-shaped cloud feature is visible near the equator. Similar features were seen from Mariner 10, Pioneer Venus, and Galileo spacecrafts. This global feature might indicate atmospheric waves, analogous to high and low pressure cells on Earth. Bright clouds toward Venus’ poles appear to follow latitude lines. The polar regions are bright, possibly showing a haze of small particles overlying the main clouds. The dark regions show the location of enhanced sulfur dioxide near the cloud tops. From previous missions, astronomers know that such features travel east to west along with the Venus’ prevailing winds, to make a complete circuit around the planet in four days. Because Venus is closer to the Sun than Earth, the planet appears to go through phases, like the Moon. When Venus swings close to Earth the planet’s disk appears to grow in size, but changes from a full disk to a crescent. The image was taken with the Wide Field Planetary Camera-2, in PC mode. False color has been used enhance cloud features.
Image Credit: NASA/JPL
NASA’s Hubble Shows Milky Way is Destined for Head-On Collision by NASA Goddard Photo and Video on Flickr.
Via Flickr:
NASA image release Thursday, May 31, 2012
Caption: This illustration shows a stage in the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy, as it will unfold over the next several billion years. In this image, representing Earth’s night sky in 3.75 billion years, Andromeda (left) fills the field of view and begins to distort the Milky Way with tidal pull.
Credit: NASA; ESA; Z. Levay and R. van der Marel, STScI; T. Hallas; and A. Mellinger
SpaceX Dragon Berths at the International Space Station (NASA, 05/25/12) by NASA’s Marshall Space Flight Center on Flickr.
Via Flickr:
With darkness, Earth’s horizon and thin line of atmosphere forming a backdrop, the SpaceX Dragon commercial cargo craft is grappled by the Canadarm2 robotic arm at the International Space Station. Expedition 31 Flight Engineers Don Pettit and Andre Kuipers grappled Dragon at 9:56 a.m. (EDT) and used the robotic arm to berth Dragon to the Earth-facing side of the station’s Harmony node at 12:02 p.m. May 25, 2012. Dragon became the first commercially developed space vehicle to be launched to the station to join Russian, European and Japanese resupply craft that service the complex while restoring a U.S. capability to deliver cargo to the orbital laboratory. Dragon is scheduled to spend about a week docked with the station before returning to Earth on May 31 for retrieval.
Image credit: NASA/JSC
