Yebes Technological Development Center
Services The Center for Technological Developments (CDT) is a branch of the National Geographic Institute of Spain. The new Radio Telescope is opened for the scientific community interested in Radio Astronomy. SPIDER Main Specifications Diameter Angular resolution Rx Bandwidth Rx Frequency channels
2.3m 7deg @ 1420MHz 2.4MHz 256
SPIDER
Can be used remotely The goal of SPIDER is to provide the opportunity for students and visitors to operate a real radio telescope, in the environment of the Yebes observatory, as the 40 meter dish is not accessible to them. The instrument can be operated remotely via internet. Many of the applications are still to be designed, in coordination with other EVN observatories which are part of the network of Visitor Centres (VC-Net) sponsored by the EC FP7 project “RadioNet”.
Yebes Technological Development Center Cerro de la Palera s/n 19141 - Yebes Guadalajara Spain Phone: (+34) 949290311 Fax: (+34) 949290063
Centro de Desarrollos Tecnológicos de Yebes Instituto Geográfico Nacional (Spain)
Phone: (+34) 949290311 Fax: (+34) 949290063 Email: b.vaquero@oan.es
Radio Astronomy outreach at the CDT
Hydrogen 21cm line
Control System and Software
Hydrogen (H) is the most abundant element in the Universe (it is
The Onsala software Qradio is used for controlling the radio
also abundant in our Galaxy). When a hyperfine transition occurs
telescope. This software communicates with “Kstars”.
the atomic Hydrogen falls to the ground state and it emits energy in the form of electromagnetic radiation with a frequency of 1420MHz (λ=21cm).
SPIDER (“Small Parabolic Instrument for Demonstration, Education, and Research”) is one of the outreach activities performed st Yebes Observatory in Guadalajara. Built by the Swedish company Are Elektronik following the principles of the
SALSA
instrument
developed
by
Onsala
Space
Observatory, SPIDER is a fully operational 2.3 meters radio
This spin flips probability is once every 10 million years. It should be hard to detect but huge amounts of atomic hydrogen in the Galaxy makes the 21cm line easy to detect.
telescope equipped with an L-band (21cm – 1420MHz) receiver and a spectrograph (352 channel correlator, 2.4MHz
Radio Astronomy Observations
total bandwidth). The beam width is 7 degrees. A low noise
Control Computer
l=180
Quadrant III
preamplifier is mounted at the antenna focus and a coax cable
Quadrant II
Galactic rotation
Perseus arm Cygnus arm Orion arm l=270
feeds the signal to a cabinet which contains the receiver,
Sun l=90
Sagittarius arm Centaurus arm
power supplies and a modem. In the antenna vertex a small dipole antenna is installed for calibration purposes. This radio
Quadrant IV
Spectrum
to access SPIDER remotely.
l=0
Milky Way. Radio observations are not affected by the
The main aim is to map the spiral arms of the Galaxy.
Quadrant I
By means of VNC it is possible
telescope is ideal for observing hydrogen in our galaxy, the
interstellar dust so it is possible to study the galaxy structure.
VNC remote access
C
10 kpc = 32 600 light-years
Observations in the Galactic disk. The purple line is the line of sight. Radio lines in the spectrum correspond to spiral arms. They are affected by the Doppler effect what gives us information about speed of movement and also distance.
Parabolic Dish
The Earth and the Sun are situated in one of the Spiral arms
SalsaJ
Analysis of the observations
Feeder
(Orion arm), approximately 25000 light years from the center of El motor
the Galaxy. Tetrapode
Milky Way artist’s view
To obtain the structure of the Milky Way it is necessary to Az motor
observe at different galactic longitudes and, from this observations, calculate the distance to clouds of hydrogen. Spider Subsystems
Receiver
Sample of acquired spectrum