Spiral Galaksi NGC 6744⠀
Büyük ve güzel spiral galaksi NGC 6744, neredeyse 175,000 ışık yılı boyunda, Samanyolu’ndan daha büyüktür. Aşağı yukarı 30 milyon ışık yılı mesafede, güney takımyıldızı Tavus’ta (Pavo) yer alır ve küçük teleskoplarda sönük, uzamış bir cisim olarak görülür. Bu yakın ada evrenin diskini, bizim bakış açımıza doğru eğilmiş olarak görüyoruz. Bu dikkat çekici derecede belirgin ve detaylı galaksi portresi, bir dolunayın açısal büyüklüğü kadar bir alanı kaplıyor. İçerisinde, dev galaksinin sarımsı çekirdeğini, yaşlı, soğuk yıldızların ışığı domine ediyor. Çekirdeğin ötesinde, genç mavi yıldız kümeleri ve pembemsi yıldız oluşum bölgeleriyle dolu spiral kollar, sol altta bulunan, Samanyolu’nun uydu galaksisi Büyük Macellan Bulutu’nu andıran daha küçük bir uydu galaksiyi süpürüp geçiyor.⠀
Görsel & Telif: Daniel Verschatse⠀
#nature #nasa #uzay #repost #apod #sky #science #suretialem #bugununkaresi #gununfotosu #uzaydanhaberler
Our Juno spacecraft has just released some exciting new science from its first close flyby of Jupiter!
In case you don’t know, the Juno spacecraft entered orbit around the gas giant on July 4, 2016…about a year ago. Since then, it has been collecting data and images from this unique vantage point.
Juno is in a polar orbit around Jupiter, which means that the majority of each orbit is spent well away from the gas giant. But once every 53 days its trajectory approaches Jupiter from above its north pole, where it begins a close two-hour transit flying north to south with its eight science instruments collecting data and its JunoCam camera snapping pictures.
Space Fact: The download of six megabytes of data collected during the two-hour transit can take one-and-a-half days!
Juno and her cloud-piercing science instruments are helping us get a better understanding of the processes happening on Jupiter. These new results portray the planet as a complex, gigantic, turbulent world that we still need to study and unravel its mysteries.
So what did this first science flyby tell us? Let’s break it down…
1. Tumultuous Cyclones
Juno’s imager, JunoCam, has showed us that both of Jupiter’s poles are covered in tumultuous cyclones and anticyclone storms, densely clustered and rubbing together. Some of these storms as large as Earth!
These storms are still puzzling. We’re still not exactly sure how they formed or how they interact with each other. Future close flybys will help us better understand these mysterious cyclones.
Seen above, waves of clouds (at 37.8 degrees latitude) dominate this three-dimensional Jovian cloudscape. JunoCam obtained this enhanced-color picture on May 19, 2017, at 5:50 UTC from an altitude of 5,500 miles (8,900 kilometers). Details as small as 4 miles (6 kilometers) across can be identified in this image.
An even closer view of the same image shows small bright high clouds that are about 16 miles (25 kilometers) across and in some areas appear to form “squall lines” (a narrow band of high winds and storms associated with a cold front). On Jupiter, clouds this high are almost certainly comprised of water and/or ammonia ice.
2. Jupiter’s Atmosphere
Juno’s Microwave Radiometer is an instrument that samples the thermal microwave radiation from Jupiter’s atmosphere from the tops of the ammonia clouds to deep within its atmosphere.
Data from this instrument suggest that the ammonia is quite variable and continues to increase as far down as we can see with MWR, which is a few hundred kilometers. In the cut-out image below, orange signifies high ammonia abundance and blue signifies low ammonia abundance. Jupiter appears to have a band around its equator high in ammonia abundance, with a column shown in orange.
Why does this ammonia matter? Well, ammonia is a good tracer of other relatively rare gases and fluids in the atmosphere…like water. Understanding the relative abundances of these materials helps us have a better idea of how and when Jupiter formed in the early solar system.
This instrument has also given us more information about Jupiter’s iconic belts and zones. Data suggest that the belt near Jupiter’s equator penetrates all the way down, while the belts and zones at other latitudes seem to evolve to other structures.
3. Stronger-Than-Expected Magnetic Field
Prior to Juno, it was known that Jupiter had the most intense magnetic field in the solar system…but measurements from Juno’s magnetometer investigation (MAG) indicate that the gas giant’s magnetic field is even stronger than models expected, and more irregular in shape.
At 7.766 Gauss, it is about 10 times stronger than the strongest magnetic field found on Earth! What is Gauss? Magnetic field strengths are measured in units called Gauss or Teslas. A magnetic field with a strength of 10,000 Gauss also has a strength of 1 Tesla.
Juno is giving us a unique view of the magnetic field close to Jupiter that we’ve never had before. For example, data from the spacecraft (displayed in the graphic above) suggests that the planet’s magnetic field is “lumpy”, meaning its stronger in some places and weaker in others. This uneven distribution suggests that the field might be generated by dynamo action (where the motion of electrically conducting fluid creates a self-sustaining magnetic field) closer to the surface, above the layer of metallic hydrogen. Juno’s orbital track is illustrated with the black curve.
4. Sounds of Jupiter
Juno also observed plasma wave signals from Jupiter’s ionosphere. This movie shows results from Juno’s radio wave detector that were recorded while it passed close to Jupiter. Waves in the plasma (the charged gas) in the upper atmosphere of Jupiter have different frequencies that depend on the types of ions present, and their densities.
Mapping out these ions in the jovian system helps us understand how the upper atmosphere works including the aurora. Beyond the visual representation of the data, the data have been made into sounds where the frequencies and playback speed have been shifted to be audible to human ears.
5. Jovian “Southern Lights”
The complexity and richness of Jupiter’s “southern lights” (also known as auroras) are on display in this animation of false-color maps from our Juno spacecraft. Auroras result when energetic electrons from the magnetosphere crash into the molecular hydrogen in the Jovian upper atmosphere. The data for this animation were obtained by Juno’s Ultraviolet Spectrograph.
During Juno’s next flyby on July 11, the spacecraft will fly directly over one of the most iconic features in the entire solar system – one that every school kid knows – Jupiter’s Great Red Spot! If anybody is going to get to the bottom of what is going on below those mammoth swirling crimson cloud tops, it’s Juno.
An 18-year-old created the world’s lightest functioning satellite, and it’s going to be launched on a real NASA mission next month.
Rifath Sharook, who is from Tamil Nadu, India, made the pocket-sized satellite for a competition called Cubes in Space,
which is an international design challenge that asks students aged 11
to 18 to fit their space-worthy invention inside a 13-foot cube.
pocket-sized 3-D printed satellite is much smaller than that. It weighs
just 0.14 pounds and will measure the rotation, acceleration and
magnetosphere of Earth, Sharook told Business Standard. Read more (5/17/17)
There are more stars in the universe than grains of sand on the world’s beaches.
More stars in the universe than seconds of time that have passed since Earth formed.
More stars than words and sounds ever uttered by all humans who have ever lived.
We asked prospective interns that follow us
on social media what questions they had for our current interns.
answered! Let’s take a look:
Answer: “Yes, sometimes astronauts request to run through the International Space Station simulation that we have using the hyper-reality lab.”
Answer: “Persistence is the key to getting your first NASA internship. Work hard, study hard, keep applying and persevere.”
Answer: “NASA is looking for passionate, smart and curious, full-time students, who are U.S. citizens, at least 16 years of age and have a minimum 3.0 GPA.”
Answer: “In addition to STEM majors, NASA has many opportunities for students studying business, photography, English, graphics and public relations.”
“The highlight has been the chance to learn a
lot more about embedded systems and coding for them, and just seeing how
everyone’s efforts in lab come together for our small part in the AVIRIS-NG
Answer: Yes! Here at the Kennedy Space Center is where all the action takes place. Check out the schedule on our website!”
“There are 10 NASA field centers and they all
Answer: “Yes, we do! I am currently working in tech development for an X-ray telescope that is launched into space to take pictures of our galaxy.”
Answer: “The greatest thing I’ve learned as a NASA intern is to not be afraid of failing and to get involved in any way you can. NASA is a very welcoming environment that offers a lot of opportunities for its interns to learn.”
Answer: My favorite experience from being a NASA intern is meeting people from all around the world and being exposed to the different cultures.”
Want to become a NASA intern? Visit intern.nasa.govto learn about the open opportunities and follow @NASAInterns on Twitter and Facebook for regular updates!