The Young Astronomers
Currently viewing the tag: "Curiosity"
In around eight hours at 06:31 am, (I’m not counting, honest) the Mars Curiosity Rover will begin her descent into the Martian atmosphere and, if all of the many stages of descent and landing go perfectly, begin her mission.
The mission itself is to find out if the past – or present – environment on mars was suitable for microbial life to inhabit the soil. The mission will last as long as Curiosity does, her plutonium power source will give her enough power to be our interplanetary geologist for at least 687 days; a Martian year.
As of an hour ago Curiosity was just 142,783 km away from Mars, less than a third of the distance Earth is from the Moon. If you’d like to know plenty more snippets like this I suggest following @MSL_101 on twitter or the official NASA account, @MarsCuriosity.
I also had to share this brilliant NASA Jet Propulsion Lab video describing the challenges faced during descent. Unsurprisingly it’s described as ‘the seven minutes of terror’:
You can find a good summary of the mission here!
NASA’s Mars Science Laboratory, Curiosity has successfully completed the largest course correction planed for its journey to the Red Planet.
Curiosity en route and operational on Mars Credit: NASA/JPL-Caltech
Over the course of three hours yesterday, the spacecraft’s thrusters were used to slightly alter the course of the probe ensuring it reaches Mars at the correct time for successful landing at the Gale Crater. Thanks to this course alteration, the craft is on target to reach Mars on the sixth of August this year.
The manoeuvre also corrects the inbuilt inaccuracy in the launch trajectory that ensures the upper stage of the launch vehicle does not impact Mars.
This is necessary as the upper stage was not subjected to the rigorous cleaning regime the probe itself was subjected to, and as such it may be carrying microorganisms from Earth that could contaminate Mars’ environment.
You can read more here.
Its that time of year again when we have a look back at all the wondrous astronomical images that have been released over the past twelve months and pick our favourites.
Obviously there are going to be some differences in opinions with some of our readers feeling like their favourite image of the year has been robbed of the top spot. Whilst we would love to feature every image, clearly that is neither practical and somewhat defeats the purpose of having a competition to pick the best. Though if you have a differing opinion we would love to hear about it, either in the comments section of the post, on our Facebook page or via our forum, but without further ado lets begin!
Best Image From Within the Solar System
This year’s winner is: - Ulyxis Rupes as observed by the ESA’s Mars Express
Springtime at Ulyxis Rupes Credits: ESA/DLR/FU Berlin (G. Neukum)
Ulyxis Rupes is a region near the Martian south pole (though the south pole itself is a little over 1000km further south). The poles of Mars are dynamic areas of the Red Planet constantly changing along with the Martian seasons. The image shows an ice field along with delicate sand dunes and numerous other interesting features.
This image was taken during the Southern Hemisphere’s Spring with the region slowly warming and the ice thinning. This warming, along with its distance from the south pole itself means the ice is rather thin, at just 500m deep compared to some other polar regions where it can reach 3.5km.
The image was taken by the ESA Mars Express’ High Resolution Stereo Camera. The Mars Express has been in orbit of Mars for 8 and a half years and continues its work of studying the Planet and mapping it in extraordinary detail.
You can read more about this image here
Best Image From Within Our Galaxy – Runner Up
Our runner up in this category is IC 2944 – The Running Chicken Nebula
IC 2944 Credit: ESO
IC 2944 is an emission nebula glowing from the harsh bombardment of the ultraviolet light produced by the hot young stars that have been birthed by the nebula’s dusty clouds.
It is located around 6500 light years from Earth in the direction of the constellation Centaurus - The Centaur.
The red glow indicates the familiar presence of excited hydrogen, a feature common in and around such star forming emission nebulae. Star formation is evidenced further by the presence of Bok Globules – the dark black objects in the image particularly concentrated in the top right corner around the cluster of bright blue stars. These are small dense regions of gas and dust that are collapsing to form the next generation of stars.
Unfortunately, such beautiful emission nebulae are short lived in astronomical terms, lasting just a few million years before their gas has either been used to forge stars or blown out from the area by fierce stellar winds. The most massive of stars will burn out in flashes as they rapidly chew through their supply of hydrogen briefly lighting up the area again as a supernova and glowing remnant.
The image was produced using data from the Wide Field Imager on the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory.
You can read more here.
Best Image From Within Our Galaxy
Our winner in this category is the glorious star forming region S106
S106 Credit: NASA ESA, Hubble Heritage Team (STScI/AURA)
The nebula is located within the constellation Cygnus – The Swan – at a distance of about 2000 light years from Earth.
The fantastic bubbles of material, with the intricate ripples of gas and dust within the surrounding nebula are caused by the young star S106 IR.
This stellar youngster is undergoing the final stages of its formation process – sucking up material from the surrounding area. Despite still undergoing its formation, S106 IR is already 15 times the mass of our of Sun.
Rather like someone whose eyes are too big for their belly, this young star is firing some of this material back off into space accompanied by large amounts of radiation that is shocking and exciting the nebula making it glow brightly.
The blue regions of emission in this image are the result of superheated hydrogen glowing at about 10,000 degrees. The cloud is only two light years across at its widest point making it a small stellar nursery (the much more famous Orion nebula is 24 light years across).
S106 is located in the direction of the constellation Cygnus and is around 1900 light years away from where you are sitting.
The image was produced from data collected by Hubble’s Wide Field Camera 3.
You can see a wider view of the entire nebula below -
S106 - Hubble and Subaru Composite Credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA) and NAOJ
You can read more about the images here
Best Extragalactic Image – Runner Up
Our runner up in this category is this ESO image of the Leo Triplet
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 (sometimes called the M66 group) 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 produced by the ESO using the Very Large Telescope’s Telescope for Surveys (try say that ten times quickly), mercifully abbreviated to VST.
It was snapped as part of a survey designed to find illusive small 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
We will be seeing the winner of the extragalactic section later, but now we move on to our amateur section,
Best Amateur Astrophotograph – Runner Up
Our runner up this year is by Milly Howes.
The ISS by Milly Howes Credit: Milly and Nick Howes
Milly took this image of an ISS pass during the STS-131 shuttle mission with her dad’s Canon EOS10D on the 26th of February 2011.
A lovely shot once again illustrating that you don’t need thousands of pounds worth of equipment to take beautiful astrophotographs.
The ISS is the largest inhabited space station ever produced by humanity. It has been occupied continuously for over 11 years.
It zips around the planet every 91 minutes at an altitude of about 380 km.
The International Space Station Credit: NASA
Best Amateur Astrophotograph
The best amateur astrophotograph of this year is this fantastic image of the Andromeda Galaxy by Nick Howes.
The Andromeda Galaxy Credit: Nick Howes
The Andromeda galaxy or M31, is the largest galaxy in our Local Group. Andromeda is a spiral galaxy similar to the Milky Way, it is located about 2.5 million light years from Earth in the direction of the constellation that shares its name.
Andromeda and the Milky Way are on a collision course and will collide in a few billion years producing a larger elliptical after many million years of gravitational distortions.
The Andromeda galaxy is the furtherest object that can be reliably observed with the naked eye. In dark skies, away from city lights it appears as a milky patch against the black of the sky.
Best Extragalactic Image and Overall 2011 Winner
This year’s best extragalactic image, and the overall winner of this year’s competition is this magnificent Hubble image of Arp 273 -
Arp 273 Credit: NASA, ESA and the Hubble Heritage Team (STScI/AURA)
Arp 273 is a pair of interacting spiral galaxies, the larger upper one on its own is UGC 1810 with the smaller lower member of the pair called UGC 1813. The pair lie 340 million light years away from us in the direction of the constellation Andromeda – The Princess.
The smaller UGC 1813 is believed to have passed through the larger galaxy, off to one side twisting the larger galaxy into a shape resembling the head of a flowering rose – as evidenced by the off centre ring structure in UGC 1810.
The smaller galaxy has only 20% the mass of the larger, though the interaction has caused the larger’s spiral arms to unfurl and for a stellar bridge of material to be thrown out thousands of light years into the void between the two.
Interactions like these generally cause starbursts to occur in both galaxies with the smaller experiencing a burst first and after a short delay a starburst is also set up in the larger galaxy. This is thought to be due to the different quantities of interstellar gas within high and low mass galaxies. In general, low mass galaxies have more gas and dust not bound into stars than high mass galaxies so it is easier for a low mass galaxy to form stars than a high mass galaxy.
A smaller third spiral can also be seen within the arms of UGC 1810. Astronomers have noted that the spiral arm changes from being ordered and reddish - indicating lots of middle age and old stars – on one side of the small spiral to being blue and clumpy on the other – indicating large numbers or recently formed high mass stars.
The image was taken using Hubble’s Wide Field Camera 3 on December 17th 2010 and had a total exposure time of 5.9 hours.
Hubble is a joint project between NASA and the ESA.
You can read more here.
That’s it for this year’s competition folks I hope you enjoyed the images for this year, and only one thing remains:
Merry Christmas
from all of us here at Sigma Orionis and the Young Astronomers
This article was produced by JansenP for the Young Astronomers
NASA has just launched the Mars Science Laboratory (MSL) from the Kennedy Space Center, in the United States. The new rover, a car-sized robot known as Curiosity, is designed to wander around the Gale Crater, on Mars to determine if the area has – or had – the environmental conditions required to support life.
It’s scientific payload is composed of 10 instruments, and each depends on electric power to operate. The energy solution adopted by rovers until now – like Spirit and Opportunity – was to catch the energy of sunlight through solar arrays. The MSL in contrast, doesn’t have solar panels to take advantage of this energy. Instead, it has a system that converts the natural heat from the decay of a radioactive material into the electricity needed to operate the rover’s instruments, robotic arm, wheels, computers and radio.
An Artist's conception of Curiosity on Mars Credit: NASA/JPL-Caltech
Transforming Heat into Electricity
A pellet of Plutonium-238. It glows due the energy released by its radioactive decay Credit: U.S. Department of Energy
The power system, the -Multi-Missions Radioisotope Thermoelectric Generator (MMRTG), is basically a nuclear battery that transforms the heat given off by a radioactive isotope (or radioisotope) source into electricity to power the probe. The heat source chosen was a 4.8 kilogram (10.6 pounds) pellet of plutonium-238 dioxide (238PuO2). This system is intend to generate about 110 watts of electrical power for at least 14 years – the MSL mission is expected to last two years, but this deadline may be extended.
Radioactive isotopes can be used as fuel because they have a very interesting propriety: due their instability, the nuclei of these isotopes (an isotope is a variation of an element i.e. – atoms of the same chemical element, but with different masses) can spontaneously “break”, turning the atom into a different element– this process is called radioactive decay. During the process, the atom release energy in form of heat that can be used by a thermoelectric generator to produce electric power.
To make this thermoelectric conversion, the generator uses a physical process known as Seebeck effect, discovered by the German physicist Thomas Seebeck. It consists of two plates, each made of a different metal. Joining these two plates to form a closed electrical circuit and keeping the two junctions at different temperatures produces an electric current. These pairs of junctions are called thermocouples.
To create this temperature difference, one of the plates is heated by the radioisotope’s decay, while the other one remains unheated and cooled by the environment.
The MMRTG also charges two lithium-ion batteries. They can be used when the rover’s energy demand temporarily exceeds the steady output level of the generator, this may occur depending on the activity the rover is performing.
Reliable Energy Anytime, Anywhere
The MMRTG is a new generation of radioisotope generators, very similar to others already present in several space missions, such as Galileo, Cassini, Voyager, New Horizons, Pioneer, Ulysses, Viking and even the manned Apollo missions to the moon. However, the MMRTG is designed to operate both on planetary bodies with an atmosphere – like Mars – and in the vacuum of the space. Moreover, on the MSL the temperature control system will use the waste heat from the radioactive decay to warm a fluid that will be pumped throughout the rover to keep the electronic components within their operating temperature range.
The Mars Science Laboratory's MMRTG, before being installed Credit: NASA/Kim Shiflett
Compared to the solar power alternative studied by MLS’ designers, the MMRTG proves to be lighter and smaller, providing a significantly better mobility and flexibility to the rover’s operations. Furthermore, as the system doesn’t depend on sunlight, it can deliver energy to the robot at anytime, even during the long Martain nights.
Though the implementation of radioactive material as a fuel requires special care. Hence, the MMRTG was built with several layers of protective material designed to contain the plutonium-238 in case of a wide range of potential accidents, such as impacts or problems during a launch. Fortunately, the type of plutonium present in the radioisotope power system is different from the material used in nuclear weapons and could never explode like a bomb.
The use of these nuclear batteries have expanded the frontiers of space exploration. Thanks to radioisotope generators, we were able to visit other worlds and send missions beyond the limits of the Sun’s influence, they have enabled achievements that would otherwise not be possible. Now, this revolutionary system will allow us to go even further and explore the mystery of life on Mars.
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