Telescopes
A compilation of my observing trips with fun facts, tips, and deadlines for proposals.
Space Telescopes
The Earth's atmosphere is quite noisy and sometimes hinders the data from ground-telescopes. So we go to Space! The resolution without the atmosphere is so much better that we obtain better science and wonderful images. We can therefore discover and study high-redshift sources in more detail.
The James Webb Space Telescope
JWST will revolutionize our view of the Universe. It has a special focus on high-redshift astronomy as it will be looking in the near and mid-infrared with an incredible resolution. I Co-PI a proposal with Dr. Micaela Bagley to confirm z ~ 9 galaxies and measure their ionizing power Looking forward to the data!
Running some of the last few tests on JWST before launch in December!
Credits: NASA/Chris Gunn.
Optical Ground-based Telescopes
Reflector telescopes using mirrors are cheaper to make and can be bigger than refractors using lenses. The bigger in diameter the mirror, the more distant objects can be observed. 10-meter class telescopes are ideal to study the EoR since we need to gather as much light as possible from high-redshift sources.
Mauna Kea Summit in Hawaii hosts 10-m class telescopes: Keck I and II, Subaru, and Gemini (N). Image credit: Keck Observatory
Radio Telescopes
Radio astronomy began by accident in 1932 when the engineer Karl Jansky, was investigating natural sources of inteference in telephone communications. He constructed an antenna and bumped into the central Black Hole in our galaxy. In radio, we can study the cold dust and gas from high-z galaxies.
We can observe our science targets during the day! The Sun's radio emission does not bother us, unlike it does for optical Telescopes.
Credit:(ESO/NAOJ/NRAO)/W. Garnier (ALMA)
W.M. Keck Observatory
Located in The Big Island of Hawaii, the observatory is at about 4,000 MASL
on the dormant volcano of Mauna Kea. The altitude and weather conditions make this observatory the perfect place to hosts two
10-meter class telescopes.
2022A call for proposals.
Observing with Steve and Rebecca. Bottom: Keck I mirror calibrations and spectra of potential high-z galaxies from MOSFIRE
The Texas team observing at Keck: R. Larson, C. Papovich, T. Hutchison, S. Finkelstein and me.
Keck I and Keck II 10-m Telescopes. Credit: Keck Observatory
W.M. Keck Observatory Headquarters, where we sleep in the day and observe at night.
Astronomers don't go up all the way to the telescopes to perform the observations, we observe from the headquartes with computers set up to communicate with the instruments at the Summit. The telescope operators, experts on the instruments, are at the telescope and help us observe the whole night. We could not do it without them!
W.M. Keck Visitor Center at the Headquarters. Plan your visit!
Nature is awesome around the Big Island, reminded me a lot of home!
Visited Mauna Loa in 2018, just a week before the eruption of Kilauea, the other active volcano of the island.
Met the Pacific Ocean for the first time, even though I am from Colombia...
La Silla Observatory
The European Southern Observatory (ESO) built its first home for telescopes in the Chilean Atacama Desert because of the beautiful night sky and dry conditions that are essential for optical telescope operations. Proposal calls vary depending on the telescope.
Telescopes at the La Silla: Left: The MPG/ESO 2.2 m telescope I used for 14 straight nights. Center (squared dome): The New Technology Telescope NTT. Right: The ESO 3.6m telescope, the biggest one here.
The MPG/ESO 2.2 m telescope getting maintance in the morning.
At the telescope there are three instruments to do observations. I use GROND to look at the quasar candidates in all available bands from optical to near-IR k and identify the photometric break indicative of the quasar's high redshift nature.
The astronomer's work station from where I manage the telescope. It's important to keep an eye in every screen to make sure the telescope and the observations are working fine.
One of the most important screens is the weather monitor. It warns us when clouds are coming and when humidity levels rise. Droplets of water entering the telescope dome is very bad for the mirror and instruments. You have to do an emergency close when buttons go red.
Living the astronomer's nightmare: clouds at dusk.
We have friendly visitors all day around the observatory.
The astronomer's sleeping area, with the Andes in the background. First time I saw the Andes naked, in Colombia they are very green covered with thick layers of vegetation.
Pretty much the only wild flower around the Observatory. This area of Chile is very dry, good for telescopes but not for plants.
La Silla also hosts other non-ESO owned telescopes such as the 1.2 m Swiss telescope. Cutest telescope I've seen.
Paranal Observatory
At Paranal are the four 8.2-m Very Large Telescope VLT. ESO hires astronomers who become experts on the telescopes at Paranal and observe all the science targets from accepted proposals. It is thus rare to have visiting astronomers outside of ESO, I was very lucky! Next call for proposals.
Visiting Paranal! (the VLT is at the back.)
The incredible VLT at the top of the mountain. The surroundings are extremely dry and desertic, not the tiniest wild plant. This is the closest I will ever be to Mars.
At the VLT UT 1 'Antu', which means Sun in Mapuche, the indigenous original inhabitants of this area of Chile.
The instruments at the UT 1 are KMOS, FORS2 (in the image), and soon MOONS.
From Paranal, you can see the construction of the upcoming European Extremely Large Telescope E-ELT, a 40-meter telescope!
This is the entrance to the residences where astronomers eat and sleep. It is located underground and far away from the telescopes, you need a car to go up and down the summit.
When entering the residence, there is a complete change of landscape. It offers a more friendly and humid environment to counteract for the extreme dry conditions of the desert.
The residence is very friendly and you get to interact with tens of astronomers and staff every day. Observers can stay up to 10 nights observing so they deffintely try to accomodate you with the best environment.
The night sky truly is amazing at the top of the observatory!
Green Bank Observatory
Located in the Quiet Zone of West Virginia, U.S. All radio signals that could intervene with our observations are banned. We shall not use a microwave or turn on our phones, so all my photos were taken with a Kodak disposable camera (forgive resolution.) Next call for proposals
The Green Bank Telescope (GBT), one of the biggest radio telescopes in the world with a dish of 100 meters in diameter.
I look so tiny on top of the GBT!
My friends from the NRAO-Charlottesville Summer Internship
We observed the Crab Nebula with the 40 feet antenna. First time I observed in the day, it felt weird but more resting.
The observatory's surroundings are beautiful! A lot of green and wild life. We had to use bikes to move around between telescopes, conference room and sleeping lounge.
A replica of the Karl Jansky's Telescope that observed the SMBH in the center of our galaxy. (Yes, this is an antenna).
The Green Bank Observatory Science Center. Here we can use computers with ethernet connection to work on the data from the telescopes... and communicate with the world.
The Very Large Array
What is better than a single dish? An array of 27 antennas observing the target at the same time, creating a single telescope that can vary in size from 1 km to 35 km in diameter, depending on the location of the antennas. Operated by NRAO and located in beautiful New Mexico. Next call for proposals
Each of the 25-m VLA antennas are identical. This one is ready to be climbed!
On top of the antenna dish showing the receiver bands and the subreflector on top hanging from a swivel!
Selfie with the 8 receiver bands! I have worked with all of these.
In ascending frequency: L, S, C, X, Ku, K, Ka, and Q bands covering continuous frequencies from ~1 Ghz to 50 Ghz.
Bottom of the L-band receiver, this size is equivalent to one pixel of your phone camera. It is much bigger because the radio photons are much weaker than those in visible light that your camera captures.
The antennas were on A-configuration, meaning covering the largest baselines of 35 km, so I could barely see the other 26 antennas from my position.
This is the transporter used to move each antenna on a special railway to get from A to B, C, or D-configuration.
Couldn't forget taking a picture of the wildlife around the observatory, some antelopes came to say hi!
The VLA site also has its own Radio Sundial.
Kitt Peak Observatory
The Observatory is part of the
National Optical Astronomy Observatory
NOAO. It is a city of telescopes in the
Kitt Peak mountains of Arizona as it hosts
over 20 telescopes of different sizes and for various astronomical objectives.
Telescopes info and calls for proposals.
I went to Kitt Peak for two nights to assist a grad student on his observing run.
Observing with Dr. Matthew Stevans to get some data for his PhD project!
We observed at the Mayall 4-m Telescope. with the NEWFIRM camera in the K-band to make a catalog of z ~ 4 galaxies.
A few telescopes at Kitt Peak as seen from the other side of the mountain.
This is the Mayall telescope!
It is very easy to go up and visit the observatory.
An overview of the observatory and the many telescopes it has, taken at the visitor center.
The McMath-Pierce Solar Telescope. Truly an architectural masterpiece for a telescope dedicated solely to looking at the Sun. I visited when it was still functional for research (2016).
McDonald Observatory
Owned by The University of Texas at Austin and located in West Texas, this is the first observatory I ever visited. All UT astronomy undergradutes have the opportunity of going on observing nights either for research or outreach. There are five telescopes and calls for proposals are trimestral.
The 82" Otto Struve was the first telescope at McDonald built in the 1930's. The telescope is at the top of a five story building. All other floors are a big library!
The Harlan J. Smith is a 107" telescope. It is one of my favorites to use and visit because it has the Tull Spectrograph. This coud´e spectrograph occupies a whole room that you can visit and see all the mirrors and instruments that help redirect the light from the observations to the detector.
The Hobby-Eberly HET 10-m telescope is certainly the one with most advanced technology. Unlike other telescopes, its mount is fixed at an angle and thus only observes 70% of the sky. It is used for the HETDEX project that I have been involved with in the past.
Me on top of the 82" observatory, with the 107" to the right and the HET on the back.
Observing the Orion Nebula. UT students get to use the 30" telescope extensively for classes: Observational Methods in Astronomy and Freshman Research Initiative.
The 36" telescope is also widely used by undergradutes when we visit the observatory as part of the UT Astronomy Students Association ASA.
The Fank N. Bash Visitor Center. They have other telescopes for outreach but you can also book a guided tour to the telescopes on Mt. Locke!
Me helping at the Visitor Center where we talked to the general public and show them a few planets with telescopes.
The general lanscape of West Texas as seen from the observatory.
Telescopes in Colombia
The National Astronomical Observatory (OAN) was the first observatory built in America in 1803. Actually, the independence of the Viceroyalty of New Granada from the Spanish Crown was planned in this building and took place on July 20, 1810.
Since The Independence, the observatory was abandoned or worked as a prison. In 1891, Julio Garavito became Colombia's first Professor in Mathematics, and Director of the OAN. Here, he studied the Moon's movement and discovered a crater on its Dark Side. Sadly, the observatory was inactive for much of the XX Century until it became part of the National University of Colombia - Bogotá. (UNC)
The UNC left the OAN as a historical site and built a modern observatory but on its university grounds in 1952. The UNC was the first university to begin a Master's Degree in Astronomy, and recently inagurated in 2017 the first Ph.D. Astronomy Program of the country. Colombia is indeed an emerging country in Astronomy and we are working hard to give more opportunities to the new generations!