The Lagrange Points

Lagrange points are named in after Italian-French mathematician Joseph-Louis Lagrange.

There are five special points where a small mass can orbit in a constant pattern with two larger masses. The Lagrange Points are positions where the gravitational pull of two large masses precisely equals the centripetal force required for a small object to move with them. This mathematical problem, known as the “General Three-Body Problem” was considered by Lagrange in his prize winning paper (Essai sur le Problème des Trois Corps, 1772).

Of the five Lagrange points, three are unstable and two are stable. The unstable Lagrange points – labeled L1, L2 and L3 – lie along the line connecting the two large masses. The stable Lagrange points – labeled L4 and L5 – form the apex of two equilateral triangles that have the large masses at their vertices. L4 leads the orbit of earth and L5 follows.

http://map.gsfc.nasa.gov/mission/observatory_l2.html

Gravitational Waves – greatest discovery of 21 century?

Perhaps, perhaps not but to this discovery opens up a who new set of eyes on the Universe. As every object orbits another it generates a graviational wave. Now scientists have been able to detect two black holes orbiting one another moving faster and faster as they slowly convege and ultimately mergy.

This discovery could assist in the study of other black holes, even the study of dark matter.

More on it here

https://www.newscientist.com/article/2077162-revolution-in-physics-as-gravitational-waves-seen-for-first-time/?utm_source=NSNS&utm_medium=SOC&utm_campaign=hoot&cmpid=SOC%7CNSNS%7C2016-GLOBAL-hoot

Jupiter at oppostion Announcement from BAA Circular

Jupiterwill be at opposition on March 8, and thus above the horizon all night long. Onestriking phenomenon for a day or so around opposition is that the galileanmoons can transit directly in front of their shadows on Jupiter’s disk. This year, on the night of March 7/8, therewill be a very rare opportunity to see both Europa and Io doing this at thesame time! Europa and its shadow moveonto the disk at 23:09-12 UT; Io and its shadow, at 00:28-29 UT, while Europais in the centre of the disk; Europa and shadow leave at 01:57-58, and Io andshadow at 02:43. This will be very wellplaced for observers all over Europe including the UK. Asecond dual phenomenon occurs on March 9 at 18:54-58 UT: Ganymede ends a transit just as Io and itsshadow begin a transit. Ganymede’sshadow remains on the disk till 19:10; Europa is hidden behind the planet. This event will be visible from America, butwill be very low in the sky for European observers. You cansee hi-res images of moons transiting in front of their shadows (one at a time),at the last 4 oppositions, on our web site at: http://www.britastro.org/jupiter/2014_15report04.htm http://www.britastro.org/jupiter/2013_14report05.htm http://www.britastro.org/jupiter/2012_13report08.htm http://www.britastro.org/jupiter/2011report02.htm Jupiter’smoons have coupled orbits, so dual transits of Europa and Io will continue tooccur at intervals of 3.5 days right up to mid-April, as well as dual transitsof Ganymede and Io on March 16, 23/24, and 31. Times are given in the BAA Handbook, and simulated views can be producedin WinJUPOS. Onemore notable and rare event occurs on April 12: Jupiter will occult a 7th-magnitudestar. Ingress is at approx. 14:45 UT,visible from the Far East and Australia. Egress is at ~17:45 UT, visible from western Asia and south-easternEurope. Although the star will be ratherfaint relative to the planet, observers with large telescopes may be able totake videos of the event, which can involve irregular fading and multipleflashes as the star passes behind the planet’s atmosphere. Details can be found in: A. A. Christou & E. Kardasis,‘Stellar occultation by Jupiter and Ganymede’, http://www.hellas-astro.gr/articles/astromanos-2015-12-13-1615Forresults from the last stellar occultation, on 2009 Aug.3/4, see the Journal ofthe BAA (2016 Feb), vol.126, p.37.

The Next Einstein?

Sabrina Gonzalez Pasterski was only 14 years old when she stepped foot into MIT’s campus offices seeking approval one morning for the single-engine plane she built.

Fast forward eight years and the 22-year-old is now an MIT graduate and Harvard Ph.D. candidate interested in answering some of the most complex questions in physics, according to Yahoo.

The first-generation Cuban-American woman has already received job offers from Jeff Bezos, the founder of Amazon.com, and aerospace developer and manufacturer Blue Origin. NASA has also shown interest in the young physicist. Pasterski’s study seeks to explore black holes and spacetime and she is particularly concentrated on explaining gravity through the context of quantum mechanics.

 

http://physicsgirl.com/

http://nextshark.com/sabrina-pasterski-22-mit-grad/