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NASA’s Hubble space telescope spots quasar tsunamis ripping across galaxies

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Quasars, biggest and distant bright objects in space that are similar to stars. Astronomers called them "quasi-stellar radio sources," or "quasars," because the signals came from one place, like a star. However, the name is a misnomer; according to the National Astronomical Observatory of Japan, only about 10 percent of quasars emit strong radio waves. NASA’s Hubble space telescope spots quasar tsunamis ripping across galaxies. Quasars give off more energy than 100 normal galaxies combined. Because they are so far away from us, it takes billions of years for the light they give off to reach Earth. The light stays the same, it just has to travel a long time to get to us. When we look at a quasar, it is like we are looking back in time. The light we see today is what the quasar looked like billions of years ago. NASA’s Hubble space telescope has helped astronomers spot quasar tsunamis ripping across galaxies. Quasars are extremely remote celestial objects, emi

NASA JUNOCAM UP TO DATE

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NASA JUNOCAM UP TO DATE WELCOME TO THE JUNOCAM COMMUNITY WHERE YOU CAN ACTIVELY PARTICIPATE IN THE MISSION! UPLOAD YOUR IMAGES OF JUPITER AND HELP US DECIDE WHAT POINTS OF INTEREST JUNOCAM WILL PHOTOGRAPH. INSTRUCTIONS FOR AMATEUR OBSERVERS The Juno mission science team strongly encourages mission-supporting observations from both the professional and amateur communities. To help us in our planning during the mission, we are accepting imaging contributions from the amateur community with a point of deposit on the Mission Juno website. Image files can be uploaded onto the site, including those from earlier in the year (e.g the epoch around Jupiter opposition in early February). We will assess our ability to work with the data received, organizing it and transforming it into a form most useful for the Juno science team. We will accept data in any form and using any filters that are available to each contributor. We note that images that will be most valuable for us should not be

Sosigenes of Alexandria

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Greek astronomer and mathematician, probably from Alexandria, employed by  Julius Caesar  to devise the  Julian calendar .  He is known as the main astronomer who helped Julius Caesar with his reform of the Roman lunar calendar, although his role in this reform is not very clear.    Plutarch  simply states, without mentioning any names, that Caesar consulted the best philosophers and mathematicians before making an improved calendar of his own.  The Romans had traditionally had a lunar 12-month calendar of 355 days. To bring it into phase with the solar year an intercalary (inserted) month of 27 days was supposed to be added every other year to a reduced February of 23 or 24 days. In theory, this should have produced a year of 366¼ days, which would have proved inaccurate in the long run but should have been controllable by skipping intercalation whenever the discrepancy became too uncomfortable.   Caesar’s adoption of the 365–l/4–day a solar year may have been one result of Sosigenes’