NASA has given us a glimpse of one of the most distant visible objects in the solar system as Japan’s space agency prepares for a close orbit of one of our nearest neighbors.
Japan’s Akatsuki probe — the name means “dawn” in Japanese — was originally launched in May 2010 but missed its window to enter orbit around Venus due to a technical malfunction, instead going spinning around the sun for five years.
Following a 20-minute blast from its thrusters, the second time lucky probe is now in orbit around the planet and in “good health,” according to the Japan Aerospace Exploration Agency (JAXA).
Sister planet
Venus offers a great deal for us to learn about the solar system and the formation of its planets, including our own, JAXA said, given that the planet is a similar size and distance from the sun as Earth and because its “birth formation is considered to be similar to that of the Earth.”
The worlds are so similar they are sometimes referred to as sister planets, with only Venus’ incredibly thick atmosphere — made up of more than 96% carbon dioxide — setting the two apart. The planet’s runaway greenhouse effect means its surface is the hottest of any planet in the solar system, at a roasting 462 degrees Celsius (863 degrees Fahrenheit), hotter even than Mercury.
Originally Akatsuki was intended to enter an elliptical orbit, 300 to 80,000 kilometers above Venus’ surface, which would enable “comprehensive observations” of the planet’s atmosphere and meteorological conditions, including the intense storms that roil its upper atmosphere.
According to the scientific journal Nature however, even on a best-case scenario, the new orbit will be far wider, reaching as far as 500,000 kilometers from the surface as it loops around the planet every 14 to 15 days.
Distant cousin
As JAXA approaches Venus, its U.S. counterpart has been examining objects at the furthest reaches of the solar system.
New Horizons, which last week beamed back the most detailed images of Pluto’s surface ever taken, has captured four photos of a Kuiper Belt object 90 miles (150 kilometers) across from a distance of 170 million miles away (280 million kilometers).
“This sets a record, by a factor of at least 15, for the closest-ever picture of a small body in the Kuiper Belt, the solar system’s ‘third zone’ beyond the inner, rocky planets and outer, icy gas giants,” the New Horizons team said in a statement.
The object — designated 1994 JR1 — was around 3.3 billion miles (5.3 billion kilometers) from the sun at the time the photos were taken, the statement said.
The Kuiper Belt describes the huge mass of just visible objects that orbit the sun beyond Neptune, including comets, frozen rocks, and three dwarf planets: Pluto, Haumea, and Makemake (of which Pluto is by far the largest and most massive).
New Horizons is planned to conduct a close flyby of another Kuiper Belt object — 2014 MU69 — in January 2019 that would give us insights into the bodies at the furthest reaches of the solar system.