In the show this time, Dr Omar Almaini tells us about the Ultra Deep Survey, Dr Eamonn Kerins discusses the VVV Survey in this month's JodBite, and your astronomical questions are answered by Dr Joe Zuntz in Ask an Astronomer.
JodBite with Dr Eamonn Kerins
Dr Eamonn Kerins, from the Jodrell Bank Centre for Astrophysics talks about the Vista Variables in The Via Lactea (VVV). This survey will perform wide field-of-view multi-epoch observations of the Galaxy's bulge and part of the disk, to produce a high resolution map of the bulge tracing the inner structure of our galaxy. The Survey uses VISTA, a 4.1 metre telescope with a near-infrared camera, located in Chile.
Interview with Dr Omar Almaini
Dr Omar Almaini is from the University of Nottingham and is leading the Ultra Deep Survey to study galaxy formation and evolution. The Ultra Deep Survey is the deepest near-infrared survey ever conducted over 1 square degree. It can detect galaxies up to redshift of 6 and 7 which is around 13 billion years ago and over two hundred and fifty galaxies have been detected so far.
Ask an Astronomer
Dr Joe Zuntz answers your astronomical questions:
- The first question is from Peter Ellinger, who says: "I listened to a podcast in which an astronomer had detected light from an ancient supernova by reflection. I wondered if this could form the base of a triangle used to measure distance to make a more accurate measurement of cosmic distance?"
- Andrew Celentano asks: "I was intrigued by your discussion on detecting dark matter and energy via the lensing phenomenon that Einstein predicted. How can this be done when there are so many masses between the observer and the most distant galaxies?"
- Randy Taylor says: "No-one ever discusses dark matter as a source for the mass to create an early supermassive black hole. Since dark matter only interacts through gravity, it could collapse and not be affected by outward radiation pressure. It seems that this is a straightforward way to create a very large object quickly in the early Universe."
- Finally, Stephen Uitti asks: "Say a photon is emitted at Last Scattering, and travels across the Universe, only to be absorbed by a detector. From the perspective of the photon it is instantly emitted, then absorbed. But photons oscillate - how do they do that?"
Odds and Ends
Lone Signal, a new METI project (Messaging to Extra Terrestrial Intelligence), is aimed at sending a constant signal, including messages from the general public to Gleise 526, a red dwarf star. People can get involved in sending 144 character text-based messages or images on their website.
China launched its fifth manned space mission this month, with three taikonauts aboard. A capsule, launched from a Long March rocket, docked with the experimental space station Tiangong-1. The crew practised docking and undocking and conducted maintenance on the station, as well as delivering live classes on microgravity to schools. Tiangong-1 has now received its last human visitors, and will be allowed to safely burn up in the atmosphere over the Pacific Ocean at an unspecified time in the future. The Chinese space programme aims to have a permanently manned space station by 2020.
A new class of variable star has been discovered in the open star cluster NGC 3766. Over a period of seven years this cluster had been monitored using the Swiss 1.2-metre Euler telescope at ESO's La Silla Observatory in Chile. Extraordinary precision was achieved measuring tiny changes in the stars magnitude over periods between about two and 20 hours.
|JodBite:||Dr Eamonn Kerins and Indy Leclercq|
|Interview:||Dr Omar Almaini and Indy Leclercq|
|Ask An Astronomer:||Dr Joe Zuntz and Christina Smith|
|Presenters:||Libby Jones, Mark Purver and Christina Smith|
|Editors:||Christina Smith and Indy Leclercq|
|Segment Voice:||Mike Peel|
|Website:||Sally Cooper and Stuart Lowe|
|Cover art:||Dry ice tracks on Mars: Several types of downhill flow features have been observed on Mars. This image from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter is an example of a type called "linear gullies". CREDIT: NASA/JPL - Caltech/Univ. of Arizona|