18th Sep 2014
spaceplasma:

Jupiter’s Irregular Satellites

The planet Jupiter has 67 confirmed moons. This gives it the largest retinue of moons with “reasonably secure” orbits of any planet in the Solar System. In fact, Jupiter and its moons are like a miniature solar system with the inner moons orbiting faster than the others. Eight of Jupiter’s moons are regular satellites, with prograde and nearly circular orbits that are not greatly inclined with respect to Jupiter’s equatorial plane. The remainder of Jupiter’s moons are irregular satellites, whose prograde and retrograde orbits are much farther from Jupiter and have high inclinations and eccentricities. These moons were probably captured by Jupiter from solar orbits. There are 17 recently discovered irregular satellites that have not yet been named.

Image Credit: NASA/ESA/Lowell Observatory/J. Spencer/JHU-APL

spaceplasma:

Jupiter’s Irregular Satellites

The planet Jupiter has 67 confirmed moons. This gives it the largest retinue of moons with “reasonably secure” orbits of any planet in the Solar System. In fact, Jupiter and its moons are like a miniature solar system with the inner moons orbiting faster than the others. Eight of Jupiter’s moons are regular satellites, with prograde and nearly circular orbits that are not greatly inclined with respect to Jupiter’s equatorial plane. The remainder of Jupiter’s moons are irregular satellites, whose prograde and retrograde orbits are much farther from Jupiter and have high inclinations and eccentricities. These moons were probably captured by Jupiter from solar orbits. There are 17 recently discovered irregular satellites that have not yet been named.

Image Credit: NASA/ESA/Lowell Observatory/J. Spencer/JHU-APL

Source: spaceplasma
16th Sep 2014

NameExoWorlds: Vote on Names for Exoplanets

The International Astronomical Union (IAU), in partnership with Zooniverse, is organizing a citizen science project to provide new names for exoplanets and their stars. This project, NameExoWorlds, will allow users to vote on names submitted by a variety of astronomy clubs and organizations. These new names will be used in addition to their current scientific names.

Available to view now is a list of exoplanets and their host stars.

More information is available in this IAU press release. Voting will occur at NameExoWorlds.org.

Source: iau.org
12th Sep 2014
ucresearch:

Seeing a supernovae within hours of the explosion
For the first time ever, scientists have gathered direct evidence of a rare Wolf-Rayet star being linked to a specific type of stellar explosion known as a Type IIb supernova. Peter Nugent of the Lawrence Berkeley National Laboratory says they caught this star – a whopping 360 million light years away – just a few hours after it exploded.
Hear more about this discovery →

ucresearch:

Seeing a supernovae within hours of the explosion

For the first time ever, scientists have gathered direct evidence of a rare Wolf-Rayet star being linked to a specific type of stellar explosion known as a Type IIb supernova. Peter Nugent of the Lawrence Berkeley National Laboratory says they caught this star – a whopping 360 million light years away – just a few hours after it exploded.

Hear more about this discovery →

9th Sep 2014
Tectonic Plates on Europa
Scientists have found evidence in favor of tectonic plates on Jupiter’s moon Europa. Images from the Galileo spacecraft have shown an expanding crust similar to mid-ocean ridges on Earth that are formed by seafloor spreading.
By studying and reconstructing the surface of the moon, the scientists have found that a large amount of the surface in the northern latitudes were missing. They believe that the missing surface crust has moved underneath another section of the surface since there is a lack of mountains in the area, suggesting subduction. In addition, ice volcanoes have been found above the subduction zones.
This evidence of geological activity shows that Europa is more Earth-like than originally thought, and it is important when considering Europa as a potential habitable world.
Image: Illustration of a subduction zone on Europa. (Credit: Noah Kroese, I.NK)

Tectonic Plates on Europa

Scientists have found evidence in favor of tectonic plates on Jupiter’s moon Europa. Images from the Galileo spacecraft have shown an expanding crust similar to mid-ocean ridges on Earth that are formed by seafloor spreading.

By studying and reconstructing the surface of the moon, the scientists have found that a large amount of the surface in the northern latitudes were missing. They believe that the missing surface crust has moved underneath another section of the surface since there is a lack of mountains in the area, suggesting subduction. In addition, ice volcanoes have been found above the subduction zones.

This evidence of geological activity shows that Europa is more Earth-like than originally thought, and it is important when considering Europa as a potential habitable world.

Image: Illustration of a subduction zone on Europa. (Credit: Noah Kroese, I.NK)

8th Sep 2014
A Map of Comet Churyumov-Gerasimenko
Presented at the 2014 European Planetary Science Congress (EPSC) was this map of the many terrains of comet 67P/Churyumov-Gerasimenko. The surface has been broken up into different regions based on the appearance of the comet. This is just a preliminary analysis of comet 67P and a more detailed analysis will follow to study its composition. This map, along with other images, will help mission scientists to determine a landing site for the Philae lander.
Image Credits: ESA / Rosetta / MPS for OSIRIS Team MPS / UPD / LAM / IAA / SSO / INTA / UPM / DASP / IDA

A Map of Comet Churyumov-Gerasimenko

Presented at the 2014 European Planetary Science Congress (EPSC) was this map of the many terrains of comet 67P/Churyumov-Gerasimenko. The surface has been broken up into different regions based on the appearance of the comet. This is just a preliminary analysis of comet 67P and a more detailed analysis will follow to study its composition. This map, along with other images, will help mission scientists to determine a landing site for the Philae lander.

Image Credits: ESA / Rosetta / MPS for OSIRIS Team MPS / UPD / LAM / IAA / SSO / INTA / UPM / DASP / IDA

5th Sep 2014
Jets of Comet Churyumov-Gerasimenko
The latest set of images from Rosetta’s NAVCAM shows that comet 67P has a jet! The image above is a composite of four smaller images of the comet. Each of these small images only covers about one quarter of the comet.
A blog post by the Planetary Society talks more about the comet as well as the process behind making this composite image.
Image Credit: ESA / Rosetta / NavCam / Emily Lakdawalla

Jets of Comet Churyumov-Gerasimenko

The latest set of images from Rosetta’s NAVCAM shows that comet 67P has a jet! The image above is a composite of four smaller images of the comet. Each of these small images only covers about one quarter of the comet.

A blog post by the Planetary Society talks more about the comet as well as the process behind making this composite image.

Image Credit: ESA / Rosetta / NavCam / Emily Lakdawalla

4th Sep 2014

New Galactic Supercluster Map Shows Milky Way’s ‘Heavenly’ Home

A new cosmic map is giving scientists an unprecedented look at the boundaries for the giant supercluster that is home to Earth’s own Milky Way galaxy and many others. Scientists even have a name for the colossal galactic group: Laniakea, Hawaiian for “immeasurable heaven.”

Image 1: Scientists have created the first map of a colossal supercluster of galaxies known as Laniakea, the home of Earth’s Milky Way galaxy and many other. This computer simulation, a still from a Nature journal video, depicts the giant supercluster, with the Milky Way’s location shown as a red dot. Credit: [Nature Video](https://www.youtube.com/watch?v=rENyyRwxpHo)

Image 2: This computer-generated depiction of the Laniakea Supercluster of galaxies, which includes the Milky Way galaxy containing Earth’s solar system, shows a view of the supercluster as seen from the supergalactic equatorial plane. Credit: SDvision interactive visualization software by DP at CEA/Saclay, France

The scientists responsible for the new 3D map suggest that the newfound Laniakea supercluster of galaxies may even be part of a still-larger structure they have not fully defined yet.

"We live in something called ‘the cosmic web,’ where galaxies are connected in tendrils separated by giant voids," said lead study author Brent Tully, an astronomer at the University of Hawaii at Honolulu.

Galactic structures in space

Galaxies are not spread randomly throughout the universe. Instead, they clump in groups, such as the one Earth is in, the Local Group, which contains dozens of galaxies. In turn, these groups are part of massive clusters made up of hundreds of galaxies, all interconnected in a web of filaments in which galaxies are strung like pearls. The colossal structures known as superclusters form at the intersections of filaments.

The giant structures making up the universe often have unclear boundaries. To better define these structures, astronomers examined Cosmicflows-2, the largest-ever catalog of the motions of galaxies, reasoning that each galaxy belongs to the structure whose gravity is making it flow toward.

"We have a new way of defining large-scale structures from the velocities of galaxies rather than just looking at their distribution in the sky," Tully said.

3rd Sep 2014
NASA and the OSIRIS-REx team invites the public to submit messages to the Asteroid Return Mission Time Capsule.
OSIRIS-REx, the Origins Spectral Interpretation Resource Identification Security Regolith Explorer, is an asteroid sample return mission. Launching in 2016, the plan is to travel to asteroid 101955 Bennu, take a sample of its carbonaceous surface, and return it to Earth in 2023 for further study.
The intent of the Asteroid Return Mission Time Capsule is to collect messages that will be about current and future Solar System exploration. Using Twitter and Instagram, we want to know how we will be communicating in the future and what we will be doing out in the Solar System. Use the hashtag #AsteroidMission to share your messages and images.
The spacecraft will save the messages in a time capsule and travel to Bennu. Once it returns in 2023 with samples of the asteroid, the mission team will open the time capsule to reveal what’s inside.
To learn more about the OSIRIS-REx mission, asteroid Bennu, and the Asteroid Time Capsule, visit the mission website.

NASA and the OSIRIS-REx team invites the public to submit messages to the Asteroid Return Mission Time Capsule.

OSIRIS-REx, the Origins Spectral Interpretation Resource Identification Security Regolith Explorer, is an asteroid sample return mission. Launching in 2016, the plan is to travel to asteroid 101955 Bennu, take a sample of its carbonaceous surface, and return it to Earth in 2023 for further study.

The intent of the Asteroid Return Mission Time Capsule is to collect messages that will be about current and future Solar System exploration. Using Twitter and Instagram, we want to know how we will be communicating in the future and what we will be doing out in the Solar System. Use the hashtag #AsteroidMission to share your messages and images.

The spacecraft will save the messages in a time capsule and travel to Bennu. Once it returns in 2023 with samples of the asteroid, the mission team will open the time capsule to reveal what’s inside.

To learn more about the OSIRIS-REx mission, asteroid Bennu, and the Asteroid Time Capsule, visit the mission website.

2nd Sep 2014

The Feynman Lectures on Physics  ➙

A complete online version of The Feynman Lectures on Physics is now available in a very nice looking HTML format. Separated by volume, and further by chapter, this new version includes equations and figures that are scalable so it can be read on any device.

29th Aug 2014

Interview with Maryam Mirzakhani, the brilliant Iranian mathematician who was the first woman to win the Fields Medal

  • Interviewer: What advice would you give lay persons who would like to know more about mathematics—what it is, what its role in our society has been and so on? What should they read? How should they proceed?
  • Dr. Mirzakhani: This is a difficult question. I don’t think that everyone should become a mathematician, but I do believe that many students don’t give mathematics a real chance. I did poorly in math for a couple of years in middle school; I was just not interested in thinking about it. I can see that without being excited mathematics can look pointless and cold. The beauty of mathematics only shows itself to more patient followers.
Source: allofthemath