“Look up at the stars and not down at your feet. Try to make sense of what you see, and wonder about what makes the universe exist. Be curious.” – Stephen Hawking
This famous quote reminds us of unexplored universe and to be curious to find about it.
Have you ever guessed what could have been stored for us in the universe, lots of mysteries unknown galaxies, stars and much more beyond our expectation and imagination.
Well the science and technology is getting advanced and as we humans are very curious in nature we are using these technologies and collecting data and making a most detailed map of 1.7 billion stars ever made, yes u read that right 1.7 billion stars !
Data made it possible.
On December 2020, astronomers were hit with a huge wave of data from the European Space Agency’s Gaia space observatory. This data includes positions, distance indicators and motions of more than one billion stars, along with high-precision measurements of asteroids within our Solar System and stars beyond our own Milky Way Galaxy.
The European Space Agency (ESA) is Europe’s gateway to space. Its mission is to shape the development of Europe’s space capability and ensure that investment in space continues to deliver benefits to the citizens of Europe and the world.
Gaia is an ambitious mission that relies on a huge human collaboration to make sense of a large volume of highly complex data. It demonstrates the need for long-term projects to guarantee progress in space science and technology and to implement even more daring scientific missions of the coming decades.
Gaia lifted off in late 2013, and began observing stars in July 2014 from a perch 1.5 million kilometers from Earth. The European Space Agency (ESA) probe continuously scans the sky as it slowly spins on itself, and it has now measured the positions of the same stars multiple times. This enables scientists to track stars’ nearly imperceptible motions across the Galaxy year after year. As Gaia orbits the Sun, its changing perspective also makes the stars’ apparent position change by tiny amounts — typically by an angle of millionths of a degree. These offsets can be used to calculate their distance from our Solar System
ESA’s Gaia mission has produced the richest star catalogue to date, including high-precision measurements of nearly 1.7 billion stars and revealing previously unseen details of our home Galaxy. A multitude of discoveries are on the horizon after this much awaited release, which is based on 22 months of charting the sky. Preliminary analysis of this phenomenal data reveals fine details about the make-up of the Milky Way’s stellar population and about how stars move, essential information for investigating the formation and evolution of our home Galaxy.
“The observations collected by Gaia are redefining the foundations of astronomy,” says Günther Hasinger, ESA Director of Science.
Gaia launched in December 2013 to map the galaxy in unprecedented detail. The $1 billion spacecraft orbits the Lagrange-2 or L2, point, a spot about 1 million miles (1.5 million kilometers) away from Earth, where the gravitational forces between our planet and the sun are balanced and the view of the sky is unobstructed. Gaia can measure about 100,000 stars each minute, or 850 million objects each day, and can scan the whole sky about once every two months. The latest trove of data improves upon the precision and scope of the two previous Gaia data sets, which were released in 2016 and 2018.
Gaia’s latest update consists of 1.3 terabytes — versus the 551 gigabytes of the previous one — and is based on around three years of data. The mission has expanded its catalogue of stars by 15%, to 1.8 billion, and its measurements have become more precise. Compared with 2018, Gaia’s distance measurements are 50% better, and those of stellar velocities are 100% better
Data from Gaia has already been used across a wide range of applications over the past four years. The mission has helped researchers find the corpse of a galaxy that the Milky Way cannibalized 10 billion years ago, spot 20 hypervelocity stars unexpectedly zooming toward the galactic center, and identify about 1,000 nearby stars where hypothetical extraterrestrials would be able to see signs of life on Earth.
Some of the new Gaia data has already been used to make discoveries. One group of researchers led by scientists at the Dresden University of Technology measured how our solar system is accelerating inside the Milky Way, using as reference points Gaia’s 1.6 million newly observed quasars, which are so far away they appear fixed in space, like galactic lighthouses.
Gaia data were used to derive the orbits of 75 globular clusters and 12 dwarf galaxies that revolve around the Milky Way, providing all-important information to study the past evolution of our Galaxy and its environment, the gravitational forces that are at play, and the distribution of the elusive dark matter that permeates galaxies.
The third Gaia data set was set to be released in 2022, but the mission scientists decided to release preliminary data now so astronomers could use it sooner, with at least two more data sets to be released in the coming years. The spacecraft will operate until at least 2022, but its mission may be extended until 2025.
Currently, researchers are involved with specific projects including large empirical and simulation data sets: spacecraft imaging data from solar system missions, spacecraft survey data for exoplanets, sky surveys at radio, infrared, and optical wavelengths, data sets from gravitational wave detectors, and cosmological simulations of large-scale structures in the universe. These data sets will provide attractive contexts for learning and applying modern analysis methods.