The Young Astronomers
From the monthly archives: July 2011
As one of the most recognised galaxy groups in the sky the Leo Triplet (a trio of interacting galaxies) has been the subject of many beautiful images over the years, though few compare to this stunning new image from the ESO.
The Leo Triplet Credit: ESO/INAF-VST/OmegaCAM. Acknowledgement: OmegaCen/Astro-WISE/Kapteyn Institute
At around 35 million light years from Earth, in the direction of, you guessed it, Leo – The Lion. Such a distance my seem large though it is a stone’s throw on terms of the universe.
All three members of the Triplet are in fact spiral galaxies not dissimilar to our own Milky Way. They each appear so different as they are visible to us from different angles. NGC 3628 is seen edge on at the left of the image whereas M 65 (in the top right hand corner) and M66 (in the bottom right) are closer to being face on and so allow us to peer at their spiral structures unhindered.
The image also contains many other galaxies that lie much further away from us. Along with many stars that lie within our own Milky Way as well as a few asteroid streaks produced by small objects in our Solar System.
The image was captured using the ESO’s VLT Survey Telescope (sometimes shortened to VST), it large field of view (twice the area of the full moon) allows it so see large tracts of the sky at once making it a valuable tool for astronomers. One of its objectives is to search for faint objects such as Brown Dwarfs and Black Holes within the Milky Way’s halo, objects normally to small and dim to be picked out but can be identified through gravitational microlensing. It will also peer deep into the universe to help expand our knowledge of the illusive dark matter.
You can read more here
This is a post by the Young Astronomers author Joseph Dudley.
On Saturday the space shuttle Atlantis touched-down for the last time at the Kennedy Space Centre in Florida, marking an end not only to its operational life, but to the entire shuttle program. In its 19-year history, the shuttle fleet has flown 355 astronauts into space, and in total there have been 135 missions, of which Atlantis has flown 33. NASA says the cost of each shuttle launch is around $450 million, and the cost of the entire program has been estimated in the range of $170 billion.
Atlantis Touches Down for the Last Time Credit: NASA/Bill Ingalls
Atlantis Fact File:
First flight: STS-51-J, 3 October 1985
Number of missions: 33
Time spent in space: 306 days
Distance travelled: 125 million miles
Satellites deployed: 14
ISS dockings: 12
Weight: 80 tons
Length: 37.2 meters
Height: 17.2 meters
Wingspan: 23.7 meters
Atlantis is the fourth of the operational orbiters, and was delivered to the Kennedy Space Centre in April 1985, for its maiden voyage on October 3rd that year. In 1989, Atlantis carried and deployed the interplanetary probes, Magellan and Galileo for their missions to Venus and Jupiter respectively, and in 1991 it carried the Gamma Ray Observatory, at the time the heaviest ever payload. Just a few days ago, Atlantis undocked from the International Space Station (ISS) for the last time, but this was not the first space-station it had docked with. In 1995, Atlantis conducted the 100th manned US space flight and made the first ever shuttle docking at the Russian space-station Mir. After Mir was abandoned and de-orbited in 2001, Atlantis delivered both the Destiny Module, an orbital research station, and the Quest Joint Airlock to the ISS. In May 2009, it was Atlantis that flew the vital servicing mission to fix the Hubble Space Telescope, installing new cameras, batteries and a gyroscope during five 7 hour space walks.
Though the shuttle program is at an end, NASA is already looking to the future. However, NASA is facing a lot of pressure to keep operating costs low; President Obama recently proposed that NASA‘s budget be frozen until 2016, whilst others in the US government are suggesting that it be cut. Despite the threats of lower funding, NASA Administrator Charlie Bolden says that “The future of human spaceflight is bright,” and that he believes that more efficient and affordable transport to and from the International Space Station can be achieved by the private sector, allowing NASA to focus on longer term plans to visit the Moon, an asteroid or even Mars. In the meantime, it appears America will have to rely upon Russian rockets to launch its astronauts for the foreseeable future.
If you missed the launch or the landing, you can catch them on YouTube here (launch) and here (landing)
The Hubble Space Telescope has been producing stunning images since its launch in 1990.
Hubble has been taking stunning images of the sky for all those years and showing us a great deal about the Universe we live in. The image below is a map of Hubble’s observations across the heavens, and it is a very impressive feat for one telescope.
A Map of Hubble's Observations Credit: NASA, ESA, HST
Hubble made its one millionth scientific observation on the fourth of July 2011. This observation was not one of the fantastic images we are all so used to Hubble producing, instead it was one of the equally, if not more important spectroscopic observations. It is this type of observation that allows astronomers to discover the composition of stars, nebulae and galaxies. They are also vital for distance calculations for objects far out into the universe.
In this case Hubble was peering into the atmosphere of the Extrasolar planet Kepler 2b (also known as HAT-P-7b). It is located nearly 1044 light years away from Earth in the direction of the constellation Cygnus.
An artist's impression of Kepler 2b Credit: NASA, ESA, and G. Bacon (STScI)
Kepler 2b is a world about one and a half the size of Jupiter with a mass of around 1.8 Jupiters. Observations suggest it orbits its star in a retrograde manner (opposite the direction of the star’s rotation) which may be explained by its orbit being disrupted early in its formation by another body.
Hubble was peering into the atmosphere of this world seeking out the spectral signature of water. It is the only telescope we currently have in operation that can produce such detailed examinations.
Hubble will continue conducting observations for several more years at least, here’s to the next million!
You can read more here.
Neptune is the eighth planet out from the sun orbiting at an average distance of 30.1 AU (slightly less than 2.8 billion miles). It is the furthest planet from the sun (since Pluto’s demotion to Dwarf Planet status) and has thirteen detected moons.
The largest of which Triton, is the seventh largest moon in the Solar System and is the only large moon to orbit its planet in a retrograde manner (a fancy way of saying it goes round Neptune the opposite way to the planet’s rotation). Triton is believed to have been captured by Neptune’s gravity and pulled into orbit around the planet. Trition’s orbit is in the process of decay, meaning that one day, several billions of years into the future, Triton will be pulled close enough to Neptune to be either torn apart by gravitational forces into a ring system, or crash into the plane’t atmosphere. Triton is currently close enough to Neptune to experience significant tidal heating and so is cryovolcanically active.
As well as being the furthest planet from the sun, Neptune was also the last to be discovered finally detected by Johann Galle on the 23rd of September 1846 using predictions based on the distortion of the orbit of Uranus made by Urbain Le Verrier. As Neptune is so far from the sun it takes a bit under 165 Earth years to complete a single orbit.
This means that Neptune has just completed its first full orbit since its discovery all those years ago.
To mark this the Hubble Space Telescope turned its gaze on Neptune and captured these magnificent images of the planet on the 25th and 26th of June.
Neptune as seen by Hubble Credit: NASA, ESA, HST
Neptune’s azure hue is due to trace volumes of methane gas in its atmosphere. The clouds seen are composed of ice crystals floating across the tips of the clouds where the temperature is a chilly -218 degrees Celsius (just 55 Kelvin). Neptune has a similar axial tilt to the Earth and so experiences seasons much like Earth does. Compared to previous observations the bulk of the cloud activity has moved from the Southern Hemisphere to the Northern Hemisphere. A major difference would be on Neptune seasons last about 40 years rather than 4 months.
Neptune is not visible to the naked eye, but can be picked out by large binoculars or an amateur telescope. Neptune is currently located in the constellation Aquarius near edge nest to the adjacent Capricorn.
You can read more here
Resuming the regular Young Astronomers Image of the Week we have this spectacular view.
LHA 120-N 44 and NGC 1929 Credit:ESO/Manu Mejias (I really recommend clicking on this one, this reduced version really doesn't do it justice)
The image comes from an area of space very close to home (in astronomical terms), the Large Magellanic Cloud (LMC), the Milky Way’s largest satellite galaxy which is just 157 thousand light years from the Earth. The image shows both the star cluster NGC 1929 and the nebula LHA 120-N 44 (often shortened to just N44) surrounding it.
NGC 1929 is a rich large star cluster that lies (like the rest of the LMC) in the direction of the southern constellation Dorado, and contains many bright, hot new stars. N44 surrounds and penetrates the cluster and is without doubt the original source of the material that formed NGC 1929′s stars. Like all star forming regions it is a diverse are that is constantly changing and evolving as a complex set of conditions interact.
The harsh ultraviolet light, and abrasive stellar winds from the new stars formed within the cluster have caused a large part of the nebula to be blown outwards, clearing the area around the stars of gas and dust. This is complimented by the blast waves produced when the high mass stars within the cluster go supernova (as some already have), this forced the material further out while heating and compressing it into the bubble wall we see today.
Despite the nebula essentially being destroyed by the very objects it created, this is not a bleak picture. As the hot and compressed bubble of material expands it ploughs into surround material compressing it as well and trigging new star formation at the edges of the region.
The image was created by Manu Mejias using data from the ESO’s VLT as part of the 2010 Hidden Treasures competition.
You can read more here.
As a small note this marks the sixth post produced for the Young Astronomers released today, setting a new record for new content 
AAPOD
Portal to the Universe
