The Hubble Space Telescope Ceased Operations Due to Malfunction
On Wednesday, November 29th, NASA confirmed that the Hubble Space Telescope automatically entered safe mode on November 23rd. This marks the third automatic shutdown since November 19th. Scientists report that the observatory is in good condition, and efforts are underway to resolve the issue and restart the Hubble. The malfunction is attributed to issues with the observatory’s gyroscopes. Gyroscopes, generally devices containing rapidly spinning wheels or circulating beams of light, assist in determining whether an object is pointing in the desired direction. The Hubble Space Telescope’s gyroscopes are quite important given the Earth-orbiting observatory is meant to identify and image very specific regions of deep space for scientists to investigate back on the ground. More specifically, they measure the telescope’s turn rates, according to a NASA statement, to get those directional readings.
In 2009, six new gyros were installed on Hubble thanks to the fifth and final space shuttle servicing mission — in which astronauts actually flew up to Earth’s orbit and physically tended to the telescope — but only three remain operational. It’s one of those three, NASA explained, that seems to be creating some trouble. It would appear that this “faulty” gyroscope is providing fluctuating readings. Those fluctuations initially sent Hubble into the automatic “safe mode” it’s currently in on Nov. 19, but then scientists brought it back online the following day. Things went downhill again on Nov. 21, but the team, sure enough, pulled Hubble out of its woes once again. However, the telescope’s most recent entrance to safe mode, on Nov. 23, has persisted.
According to NASA’s statement, “During safe mode, science operations are suspended, and the telescope awaits new commands from the ground.”
This malfunction is not the first gyroscope issue encountered by the Hubble. For instance, in 2018, the Hubble entered safe mode for almost the same reason, and the gyroscope completely failed during that incident, possibly resulting in a worse situation than the current one. It later came back online and continued providing us with galactic images filled with scientific data.
According to NASA, the Hubble doesn’t even need to use its all remaining three gyroscopes. Scientists taps into the entire set for maximum efficiency, but theoretically, the telescope can function just fine with one.
Satellite Types and Varieties
A satellite is defined as a celestial body orbiting around a planet or another celestial object in a fixed orbit. Satellites are classified into two types: natural and artificial.
These are celestial bodies that orbit around a planet or another satellite in a specific orbit. To be classified as “natural,” these satellites must not be artificially created or influenced by human activities.
Artificial satellites are developed by humans and placed into orbit around the Earth or other planets. Equipped with sophisticated instruments and cameras, these satellites are designed to study Earth, other planets, facilitate communication, and observe deep space. Due to their wide field of view and enhanced spatial resolution, artificial satellites can collect information much faster than ground-based sensors. Additionally, unlike observations from Earth-based observatories, images from space are not affected by atmospheric conditions such as clouds and dust. Artificial satellites are launched into space to fulfill various tasks, including communication, scientific research, weather forecasting, and field observations.
What are the types of artificial satellites?
After being launched, a satellite is placed into one of several predetermined orbits around the Earth. However, in some cases, satellites can be directed on interplanetary journeys, following orbits around the Sun until reaching their final destination.
Satellites are generally classified based on their orbital altitudes, which directly affect their coverage area and travel speeds around the planet. When selecting the orbit type, developers consider the satellite’s purpose, the data it collects, the services it provides, the costs of potential orbits, coverage areas, and feasibility.
There are five main satellite types based on their orbits:
Low Earth Orbit (LEO)
Medium Earth Orbit (MEO)
Geostationary Orbit (GEO)
Sun-Synchronous Orbit (SSO)
Geostationary Transfer Orbit (GTO)
Low Earth Orbit (LEO) Satellites:
LEO satellites move at altitudes of approximately 160-1,500 kilometers above the Earth’s surface, with a short orbital period ranging from 90 to 120 minutes. Their ability to rapidly acquire and transmit data makes them suitable for remote sensing, high-resolution Earth observation, and scientific research.
Medium Earth Orbit (MEO) Satellites:
MEO satellites are positioned between low Earth and geostationary orbits, typically at altitudes ranging from 5,000 to 20,000 kilometers. MEO satellites are widely used in positioning and navigation services.
Geostationary Orbit (GEO) Satellites:
Satellites in geostationary orbit are located approximately 35,000 kilometers above the Earth’s surface. They remain stationary relative to a fixed point on Earth and are commonly used for communication purposes.
Sun-Synchronous Orbit (SSO) Satellites:
SSO satellites orbit at an altitude of around 600-800 kilometers from Earth’s surface. They are ideal for Earth observation and environmental monitoring.
Geostationary Transfer Orbit (GTO) Satellites:
This is the most common type of transfer orbit used for transitioning from a transfer orbit to a geostationary orbit.
Today, the most common satellite types based on their applications are communication satellites, Earth observation satellites, navigation satellites, and astronomical observation satellites.
Why Do We Always See the Same Side of the Moon?
Have you ever wondered why we always see the same side of the Moon that illuminates our sky? Although this is thought to be a coincidence, there is a scientific explanation. As it is known, the Moon completes its orbit around our planet every 27 days. We know that it rotates around itself in the same way, but we always see the same face during this time…
Of course, the Moon was not always like this; when it first started to form, it had a speed that was very incompatible with the Earth, so its rotation time around itself and our planet was different. Over a long time, the gravitational force exerted by the Earth caused the Moon to deform and certain changes occurred in its speed. More gravitational force began to be applied to the side of the Moon facing us than to the dark side. Over time, the time it takes for the Moon to orbit the Earth has become equal.
It seems logical to think that we should see all sides of the Moon since it rotates both around itself and around our planet, but we do not take into account the speed at which the Moon rotates around itself and around the Earth. Although the moon actually tries to change the face it shows us, the world prevents this; Since the Moon, which travels around the Earth in 27 days, takes the same time to complete its orbit around itself, it rotates equally around itself and around us at the end of a month. This is the situation that prevents us from seeing the dark side of the Moon and allows us to always see the same hemisphere. In fact, this is the case for other planets and their moons in the solar system. If you lived on Saturn, you would only see one side of Titan, that is the Solar System’s second largest moon.
Going back to this situation of the Moon, although the same side always appears to us, the size of the area we see changes from time to time. This is because the Moon’s orbit around the Earth is circular-elliptical. Orbit causes the Moon’s distance from the Earth to change at certain times. When it gets closer, the Super Moon event occurs. You may have observed that we sometimes see the polar regions of the Moon. This is because the Moon’s rotation axis is at oblique angles to its orbit around the Earth. This is the second reason why the area we see on the Moon periodically changes size.
It is a series of meetings held periodically in the field of Physics and Chemistry since 1911. It is known for the gathering of scientists who have influenced the course of history, have received and are in the process of receiving the Nobel Prize. It is widely known from the Physics Conference held in 1927. The gathering of important scientists such as Werner Heisenberg and Marie Curie made this conference even more important.
The first Solvay Conference was held in Brussels in 1911, under the chairmanship of Dutch physicist Hendrick A. Lorentz, with the support of Ernest Solvay, the owner of a chemical company. At the conference on Radiation and Quantum, the problems caused by including classical physics and quantum theory were discussed. Important scientists such as Albert Einstein, Niels Bohr, Werner Heisenberg, Max Planck and Marie Curie attended.
This conference on ‘Electrons and Photons’, which is considered the most famous of the Solvay conferences, is a historical turning point in terms of officially explaining modern quantum theory to the world physics community.
The quantum idea, which emerged in the theoretical studies at previous conferences, was obtaining results that were not based on a solid theory. This period, called “old quantum theory”, began with Heisenberg’s discovery of matrix mechanics in 1925, Schroedinger’s discovery of the wave equation named after him in 1926, and then Dirac’s “Transformation Theory”, which combined the two in a more general framework. It ended with its construction and the fifth conference.
The Solvay Conference still continues today; It was held in 2014 in the field of Physics under the title of “Astrophysics and Cosmology” under the chairmanship of Roger Blandfor, and in 2016 in the field of Chemistry under the title “Catalysis in Biology and Chemistry” under the chairmanship of Robert Grubbs and Kurt Wütrich.
This Week in Our Art Corner
The Hubble Repair Mission Documentary
Embark on an extraordinary journey through the captivating saga of the Hubble Space Telescope, from its ambitious launch to the critical repairs in space. Explore the story of a tiny flaw that led to blurred images and the heroic efforts of astronauts to rescue this iconic telescope. It’s a remarkable tale of human ingenuity, unwavering perseverance, and the relentless quest to unravel the universe’s deepest mysteries.